| 1 | /* Target-struct-independent code to start (run) and stop an inferior |
| 2 | process. |
| 3 | |
| 4 | Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, |
| 5 | 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, |
| 6 | 2008 Free Software Foundation, Inc. |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 3 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "gdb_string.h" |
| 25 | #include <ctype.h> |
| 26 | #include "symtab.h" |
| 27 | #include "frame.h" |
| 28 | #include "inferior.h" |
| 29 | #include "exceptions.h" |
| 30 | #include "breakpoint.h" |
| 31 | #include "gdb_wait.h" |
| 32 | #include "gdbcore.h" |
| 33 | #include "gdbcmd.h" |
| 34 | #include "cli/cli-script.h" |
| 35 | #include "target.h" |
| 36 | #include "gdbthread.h" |
| 37 | #include "annotate.h" |
| 38 | #include "symfile.h" |
| 39 | #include "top.h" |
| 40 | #include <signal.h> |
| 41 | #include "inf-loop.h" |
| 42 | #include "regcache.h" |
| 43 | #include "value.h" |
| 44 | #include "observer.h" |
| 45 | #include "language.h" |
| 46 | #include "solib.h" |
| 47 | #include "main.h" |
| 48 | |
| 49 | #include "gdb_assert.h" |
| 50 | #include "mi/mi-common.h" |
| 51 | |
| 52 | /* Prototypes for local functions */ |
| 53 | |
| 54 | static void signals_info (char *, int); |
| 55 | |
| 56 | static void handle_command (char *, int); |
| 57 | |
| 58 | static void sig_print_info (enum target_signal); |
| 59 | |
| 60 | static void sig_print_header (void); |
| 61 | |
| 62 | static void resume_cleanups (void *); |
| 63 | |
| 64 | static int hook_stop_stub (void *); |
| 65 | |
| 66 | static int restore_selected_frame (void *); |
| 67 | |
| 68 | static void build_infrun (void); |
| 69 | |
| 70 | static int follow_fork (void); |
| 71 | |
| 72 | static void set_schedlock_func (char *args, int from_tty, |
| 73 | struct cmd_list_element *c); |
| 74 | |
| 75 | struct execution_control_state; |
| 76 | |
| 77 | static int currently_stepping (struct execution_control_state *ecs); |
| 78 | |
| 79 | static void xdb_handle_command (char *args, int from_tty); |
| 80 | |
| 81 | static int prepare_to_proceed (int); |
| 82 | |
| 83 | void _initialize_infrun (void); |
| 84 | |
| 85 | /* When set, stop the 'step' command if we enter a function which has |
| 86 | no line number information. The normal behavior is that we step |
| 87 | over such function. */ |
| 88 | int step_stop_if_no_debug = 0; |
| 89 | static void |
| 90 | show_step_stop_if_no_debug (struct ui_file *file, int from_tty, |
| 91 | struct cmd_list_element *c, const char *value) |
| 92 | { |
| 93 | fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value); |
| 94 | } |
| 95 | |
| 96 | /* In asynchronous mode, but simulating synchronous execution. */ |
| 97 | |
| 98 | int sync_execution = 0; |
| 99 | |
| 100 | /* wait_for_inferior and normal_stop use this to notify the user |
| 101 | when the inferior stopped in a different thread than it had been |
| 102 | running in. */ |
| 103 | |
| 104 | static ptid_t previous_inferior_ptid; |
| 105 | |
| 106 | int debug_displaced = 0; |
| 107 | static void |
| 108 | show_debug_displaced (struct ui_file *file, int from_tty, |
| 109 | struct cmd_list_element *c, const char *value) |
| 110 | { |
| 111 | fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value); |
| 112 | } |
| 113 | |
| 114 | static int debug_infrun = 0; |
| 115 | static void |
| 116 | show_debug_infrun (struct ui_file *file, int from_tty, |
| 117 | struct cmd_list_element *c, const char *value) |
| 118 | { |
| 119 | fprintf_filtered (file, _("Inferior debugging is %s.\n"), value); |
| 120 | } |
| 121 | |
| 122 | /* If the program uses ELF-style shared libraries, then calls to |
| 123 | functions in shared libraries go through stubs, which live in a |
| 124 | table called the PLT (Procedure Linkage Table). The first time the |
| 125 | function is called, the stub sends control to the dynamic linker, |
| 126 | which looks up the function's real address, patches the stub so |
| 127 | that future calls will go directly to the function, and then passes |
| 128 | control to the function. |
| 129 | |
| 130 | If we are stepping at the source level, we don't want to see any of |
| 131 | this --- we just want to skip over the stub and the dynamic linker. |
| 132 | The simple approach is to single-step until control leaves the |
| 133 | dynamic linker. |
| 134 | |
| 135 | However, on some systems (e.g., Red Hat's 5.2 distribution) the |
| 136 | dynamic linker calls functions in the shared C library, so you |
| 137 | can't tell from the PC alone whether the dynamic linker is still |
| 138 | running. In this case, we use a step-resume breakpoint to get us |
| 139 | past the dynamic linker, as if we were using "next" to step over a |
| 140 | function call. |
| 141 | |
| 142 | IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic |
| 143 | linker code or not. Normally, this means we single-step. However, |
| 144 | if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an |
| 145 | address where we can place a step-resume breakpoint to get past the |
| 146 | linker's symbol resolution function. |
| 147 | |
| 148 | IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a |
| 149 | pretty portable way, by comparing the PC against the address ranges |
| 150 | of the dynamic linker's sections. |
| 151 | |
| 152 | SKIP_SOLIB_RESOLVER is generally going to be system-specific, since |
| 153 | it depends on internal details of the dynamic linker. It's usually |
| 154 | not too hard to figure out where to put a breakpoint, but it |
| 155 | certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of |
| 156 | sanity checking. If it can't figure things out, returning zero and |
| 157 | getting the (possibly confusing) stepping behavior is better than |
| 158 | signalling an error, which will obscure the change in the |
| 159 | inferior's state. */ |
| 160 | |
| 161 | /* This function returns TRUE if pc is the address of an instruction |
| 162 | that lies within the dynamic linker (such as the event hook, or the |
| 163 | dld itself). |
| 164 | |
| 165 | This function must be used only when a dynamic linker event has |
| 166 | been caught, and the inferior is being stepped out of the hook, or |
| 167 | undefined results are guaranteed. */ |
| 168 | |
| 169 | #ifndef SOLIB_IN_DYNAMIC_LINKER |
| 170 | #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0 |
| 171 | #endif |
| 172 | |
| 173 | |
| 174 | /* Convert the #defines into values. This is temporary until wfi control |
| 175 | flow is completely sorted out. */ |
| 176 | |
| 177 | #ifndef CANNOT_STEP_HW_WATCHPOINTS |
| 178 | #define CANNOT_STEP_HW_WATCHPOINTS 0 |
| 179 | #else |
| 180 | #undef CANNOT_STEP_HW_WATCHPOINTS |
| 181 | #define CANNOT_STEP_HW_WATCHPOINTS 1 |
| 182 | #endif |
| 183 | |
| 184 | /* Tables of how to react to signals; the user sets them. */ |
| 185 | |
| 186 | static unsigned char *signal_stop; |
| 187 | static unsigned char *signal_print; |
| 188 | static unsigned char *signal_program; |
| 189 | |
| 190 | #define SET_SIGS(nsigs,sigs,flags) \ |
| 191 | do { \ |
| 192 | int signum = (nsigs); \ |
| 193 | while (signum-- > 0) \ |
| 194 | if ((sigs)[signum]) \ |
| 195 | (flags)[signum] = 1; \ |
| 196 | } while (0) |
| 197 | |
| 198 | #define UNSET_SIGS(nsigs,sigs,flags) \ |
| 199 | do { \ |
| 200 | int signum = (nsigs); \ |
| 201 | while (signum-- > 0) \ |
| 202 | if ((sigs)[signum]) \ |
| 203 | (flags)[signum] = 0; \ |
| 204 | } while (0) |
| 205 | |
| 206 | /* Value to pass to target_resume() to cause all threads to resume */ |
| 207 | |
| 208 | #define RESUME_ALL (pid_to_ptid (-1)) |
| 209 | |
| 210 | /* Command list pointer for the "stop" placeholder. */ |
| 211 | |
| 212 | static struct cmd_list_element *stop_command; |
| 213 | |
| 214 | /* Function inferior was in as of last step command. */ |
| 215 | |
| 216 | static struct symbol *step_start_function; |
| 217 | |
| 218 | /* Nonzero if we are presently stepping over a breakpoint. |
| 219 | |
| 220 | If we hit a breakpoint or watchpoint, and then continue, |
| 221 | we need to single step the current thread with breakpoints |
| 222 | disabled, to avoid hitting the same breakpoint or |
| 223 | watchpoint again. And we should step just a single |
| 224 | thread and keep other threads stopped, so that |
| 225 | other threads don't miss breakpoints while they are removed. |
| 226 | |
| 227 | So, this variable simultaneously means that we need to single |
| 228 | step the current thread, keep other threads stopped, and that |
| 229 | breakpoints should be removed while we step. |
| 230 | |
| 231 | This variable is set either: |
| 232 | - in proceed, when we resume inferior on user's explicit request |
| 233 | - in keep_going, if handle_inferior_event decides we need to |
| 234 | step over breakpoint. |
| 235 | |
| 236 | The variable is cleared in clear_proceed_status, called every |
| 237 | time before we call proceed. The proceed calls wait_for_inferior, |
| 238 | which calls handle_inferior_event in a loop, and until |
| 239 | wait_for_inferior exits, this variable is changed only by keep_going. */ |
| 240 | |
| 241 | static int stepping_over_breakpoint; |
| 242 | |
| 243 | /* Nonzero if we want to give control to the user when we're notified |
| 244 | of shared library events by the dynamic linker. */ |
| 245 | static int stop_on_solib_events; |
| 246 | static void |
| 247 | show_stop_on_solib_events (struct ui_file *file, int from_tty, |
| 248 | struct cmd_list_element *c, const char *value) |
| 249 | { |
| 250 | fprintf_filtered (file, _("Stopping for shared library events is %s.\n"), |
| 251 | value); |
| 252 | } |
| 253 | |
| 254 | /* Nonzero means expecting a trace trap |
| 255 | and should stop the inferior and return silently when it happens. */ |
| 256 | |
| 257 | int stop_after_trap; |
| 258 | |
| 259 | /* Nonzero means expecting a trap and caller will handle it themselves. |
| 260 | It is used after attach, due to attaching to a process; |
| 261 | when running in the shell before the child program has been exec'd; |
| 262 | and when running some kinds of remote stuff (FIXME?). */ |
| 263 | |
| 264 | enum stop_kind stop_soon; |
| 265 | |
| 266 | /* Nonzero if proceed is being used for a "finish" command or a similar |
| 267 | situation when stop_registers should be saved. */ |
| 268 | |
| 269 | int proceed_to_finish; |
| 270 | |
| 271 | /* Save register contents here when about to pop a stack dummy frame, |
| 272 | if-and-only-if proceed_to_finish is set. |
| 273 | Thus this contains the return value from the called function (assuming |
| 274 | values are returned in a register). */ |
| 275 | |
| 276 | struct regcache *stop_registers; |
| 277 | |
| 278 | /* Nonzero after stop if current stack frame should be printed. */ |
| 279 | |
| 280 | static int stop_print_frame; |
| 281 | |
| 282 | /* Step-resume or longjmp-resume breakpoint. */ |
| 283 | static struct breakpoint *step_resume_breakpoint = NULL; |
| 284 | |
| 285 | /* This is a cached copy of the pid/waitstatus of the last event |
| 286 | returned by target_wait()/deprecated_target_wait_hook(). This |
| 287 | information is returned by get_last_target_status(). */ |
| 288 | static ptid_t target_last_wait_ptid; |
| 289 | static struct target_waitstatus target_last_waitstatus; |
| 290 | |
| 291 | /* This is used to remember when a fork, vfork or exec event |
| 292 | was caught by a catchpoint, and thus the event is to be |
| 293 | followed at the next resume of the inferior, and not |
| 294 | immediately. */ |
| 295 | static struct |
| 296 | { |
| 297 | enum target_waitkind kind; |
| 298 | struct |
| 299 | { |
| 300 | ptid_t parent_pid; |
| 301 | ptid_t child_pid; |
| 302 | } |
| 303 | fork_event; |
| 304 | char *execd_pathname; |
| 305 | } |
| 306 | pending_follow; |
| 307 | |
| 308 | static const char follow_fork_mode_child[] = "child"; |
| 309 | static const char follow_fork_mode_parent[] = "parent"; |
| 310 | |
| 311 | static const char *follow_fork_mode_kind_names[] = { |
| 312 | follow_fork_mode_child, |
| 313 | follow_fork_mode_parent, |
| 314 | NULL |
| 315 | }; |
| 316 | |
| 317 | static const char *follow_fork_mode_string = follow_fork_mode_parent; |
| 318 | static void |
| 319 | show_follow_fork_mode_string (struct ui_file *file, int from_tty, |
| 320 | struct cmd_list_element *c, const char *value) |
| 321 | { |
| 322 | fprintf_filtered (file, _("\ |
| 323 | Debugger response to a program call of fork or vfork is \"%s\".\n"), |
| 324 | value); |
| 325 | } |
| 326 | \f |
| 327 | |
| 328 | static int |
| 329 | follow_fork (void) |
| 330 | { |
| 331 | int follow_child = (follow_fork_mode_string == follow_fork_mode_child); |
| 332 | |
| 333 | return target_follow_fork (follow_child); |
| 334 | } |
| 335 | |
| 336 | void |
| 337 | follow_inferior_reset_breakpoints (void) |
| 338 | { |
| 339 | /* Was there a step_resume breakpoint? (There was if the user |
| 340 | did a "next" at the fork() call.) If so, explicitly reset its |
| 341 | thread number. |
| 342 | |
| 343 | step_resumes are a form of bp that are made to be per-thread. |
| 344 | Since we created the step_resume bp when the parent process |
| 345 | was being debugged, and now are switching to the child process, |
| 346 | from the breakpoint package's viewpoint, that's a switch of |
| 347 | "threads". We must update the bp's notion of which thread |
| 348 | it is for, or it'll be ignored when it triggers. */ |
| 349 | |
| 350 | if (step_resume_breakpoint) |
| 351 | breakpoint_re_set_thread (step_resume_breakpoint); |
| 352 | |
| 353 | /* Reinsert all breakpoints in the child. The user may have set |
| 354 | breakpoints after catching the fork, in which case those |
| 355 | were never set in the child, but only in the parent. This makes |
| 356 | sure the inserted breakpoints match the breakpoint list. */ |
| 357 | |
| 358 | breakpoint_re_set (); |
| 359 | insert_breakpoints (); |
| 360 | } |
| 361 | |
| 362 | /* EXECD_PATHNAME is assumed to be non-NULL. */ |
| 363 | |
| 364 | static void |
| 365 | follow_exec (ptid_t pid, char *execd_pathname) |
| 366 | { |
| 367 | ptid_t saved_pid = pid; |
| 368 | struct target_ops *tgt; |
| 369 | |
| 370 | /* This is an exec event that we actually wish to pay attention to. |
| 371 | Refresh our symbol table to the newly exec'd program, remove any |
| 372 | momentary bp's, etc. |
| 373 | |
| 374 | If there are breakpoints, they aren't really inserted now, |
| 375 | since the exec() transformed our inferior into a fresh set |
| 376 | of instructions. |
| 377 | |
| 378 | We want to preserve symbolic breakpoints on the list, since |
| 379 | we have hopes that they can be reset after the new a.out's |
| 380 | symbol table is read. |
| 381 | |
| 382 | However, any "raw" breakpoints must be removed from the list |
| 383 | (e.g., the solib bp's), since their address is probably invalid |
| 384 | now. |
| 385 | |
| 386 | And, we DON'T want to call delete_breakpoints() here, since |
| 387 | that may write the bp's "shadow contents" (the instruction |
| 388 | value that was overwritten witha TRAP instruction). Since |
| 389 | we now have a new a.out, those shadow contents aren't valid. */ |
| 390 | update_breakpoints_after_exec (); |
| 391 | |
| 392 | /* If there was one, it's gone now. We cannot truly step-to-next |
| 393 | statement through an exec(). */ |
| 394 | step_resume_breakpoint = NULL; |
| 395 | step_range_start = 0; |
| 396 | step_range_end = 0; |
| 397 | |
| 398 | /* What is this a.out's name? */ |
| 399 | printf_unfiltered (_("Executing new program: %s\n"), execd_pathname); |
| 400 | |
| 401 | /* We've followed the inferior through an exec. Therefore, the |
| 402 | inferior has essentially been killed & reborn. */ |
| 403 | |
| 404 | gdb_flush (gdb_stdout); |
| 405 | generic_mourn_inferior (); |
| 406 | /* Because mourn_inferior resets inferior_ptid. */ |
| 407 | inferior_ptid = saved_pid; |
| 408 | |
| 409 | if (gdb_sysroot && *gdb_sysroot) |
| 410 | { |
| 411 | char *name = alloca (strlen (gdb_sysroot) |
| 412 | + strlen (execd_pathname) |
| 413 | + 1); |
| 414 | strcpy (name, gdb_sysroot); |
| 415 | strcat (name, execd_pathname); |
| 416 | execd_pathname = name; |
| 417 | } |
| 418 | |
| 419 | /* That a.out is now the one to use. */ |
| 420 | exec_file_attach (execd_pathname, 0); |
| 421 | |
| 422 | /* Reset the shared library package. This ensures that we get a |
| 423 | shlib event when the child reaches "_start", at which point the |
| 424 | dld will have had a chance to initialize the child. */ |
| 425 | /* Also, loading a symbol file below may trigger symbol lookups, and |
| 426 | we don't want those to be satisfied by the libraries of the |
| 427 | previous incarnation of this process. */ |
| 428 | no_shared_libraries (NULL, 0); |
| 429 | |
| 430 | /* Load the main file's symbols. */ |
| 431 | symbol_file_add_main (execd_pathname, 0); |
| 432 | |
| 433 | #ifdef SOLIB_CREATE_INFERIOR_HOOK |
| 434 | SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid)); |
| 435 | #else |
| 436 | solib_create_inferior_hook (); |
| 437 | #endif |
| 438 | |
| 439 | /* Reinsert all breakpoints. (Those which were symbolic have |
| 440 | been reset to the proper address in the new a.out, thanks |
| 441 | to symbol_file_command...) */ |
| 442 | insert_breakpoints (); |
| 443 | |
| 444 | /* The next resume of this inferior should bring it to the shlib |
| 445 | startup breakpoints. (If the user had also set bp's on |
| 446 | "main" from the old (parent) process, then they'll auto- |
| 447 | matically get reset there in the new process.) */ |
| 448 | } |
| 449 | |
| 450 | /* Non-zero if we just simulating a single-step. This is needed |
| 451 | because we cannot remove the breakpoints in the inferior process |
| 452 | until after the `wait' in `wait_for_inferior'. */ |
| 453 | static int singlestep_breakpoints_inserted_p = 0; |
| 454 | |
| 455 | /* The thread we inserted single-step breakpoints for. */ |
| 456 | static ptid_t singlestep_ptid; |
| 457 | |
| 458 | /* PC when we started this single-step. */ |
| 459 | static CORE_ADDR singlestep_pc; |
| 460 | |
| 461 | /* If another thread hit the singlestep breakpoint, we save the original |
| 462 | thread here so that we can resume single-stepping it later. */ |
| 463 | static ptid_t saved_singlestep_ptid; |
| 464 | static int stepping_past_singlestep_breakpoint; |
| 465 | |
| 466 | /* If not equal to null_ptid, this means that after stepping over breakpoint |
| 467 | is finished, we need to switch to deferred_step_ptid, and step it. |
| 468 | |
| 469 | The use case is when one thread has hit a breakpoint, and then the user |
| 470 | has switched to another thread and issued 'step'. We need to step over |
| 471 | breakpoint in the thread which hit the breakpoint, but then continue |
| 472 | stepping the thread user has selected. */ |
| 473 | static ptid_t deferred_step_ptid; |
| 474 | \f |
| 475 | /* Displaced stepping. */ |
| 476 | |
| 477 | /* In non-stop debugging mode, we must take special care to manage |
| 478 | breakpoints properly; in particular, the traditional strategy for |
| 479 | stepping a thread past a breakpoint it has hit is unsuitable. |
| 480 | 'Displaced stepping' is a tactic for stepping one thread past a |
| 481 | breakpoint it has hit while ensuring that other threads running |
| 482 | concurrently will hit the breakpoint as they should. |
| 483 | |
| 484 | The traditional way to step a thread T off a breakpoint in a |
| 485 | multi-threaded program in all-stop mode is as follows: |
| 486 | |
| 487 | a0) Initially, all threads are stopped, and breakpoints are not |
| 488 | inserted. |
| 489 | a1) We single-step T, leaving breakpoints uninserted. |
| 490 | a2) We insert breakpoints, and resume all threads. |
| 491 | |
| 492 | In non-stop debugging, however, this strategy is unsuitable: we |
| 493 | don't want to have to stop all threads in the system in order to |
| 494 | continue or step T past a breakpoint. Instead, we use displaced |
| 495 | stepping: |
| 496 | |
| 497 | n0) Initially, T is stopped, other threads are running, and |
| 498 | breakpoints are inserted. |
| 499 | n1) We copy the instruction "under" the breakpoint to a separate |
| 500 | location, outside the main code stream, making any adjustments |
| 501 | to the instruction, register, and memory state as directed by |
| 502 | T's architecture. |
| 503 | n2) We single-step T over the instruction at its new location. |
| 504 | n3) We adjust the resulting register and memory state as directed |
| 505 | by T's architecture. This includes resetting T's PC to point |
| 506 | back into the main instruction stream. |
| 507 | n4) We resume T. |
| 508 | |
| 509 | This approach depends on the following gdbarch methods: |
| 510 | |
| 511 | - gdbarch_max_insn_length and gdbarch_displaced_step_location |
| 512 | indicate where to copy the instruction, and how much space must |
| 513 | be reserved there. We use these in step n1. |
| 514 | |
| 515 | - gdbarch_displaced_step_copy_insn copies a instruction to a new |
| 516 | address, and makes any necessary adjustments to the instruction, |
| 517 | register contents, and memory. We use this in step n1. |
| 518 | |
| 519 | - gdbarch_displaced_step_fixup adjusts registers and memory after |
| 520 | we have successfuly single-stepped the instruction, to yield the |
| 521 | same effect the instruction would have had if we had executed it |
| 522 | at its original address. We use this in step n3. |
| 523 | |
| 524 | - gdbarch_displaced_step_free_closure provides cleanup. |
| 525 | |
| 526 | The gdbarch_displaced_step_copy_insn and |
| 527 | gdbarch_displaced_step_fixup functions must be written so that |
| 528 | copying an instruction with gdbarch_displaced_step_copy_insn, |
| 529 | single-stepping across the copied instruction, and then applying |
| 530 | gdbarch_displaced_insn_fixup should have the same effects on the |
| 531 | thread's memory and registers as stepping the instruction in place |
| 532 | would have. Exactly which responsibilities fall to the copy and |
| 533 | which fall to the fixup is up to the author of those functions. |
| 534 | |
| 535 | See the comments in gdbarch.sh for details. |
| 536 | |
| 537 | Note that displaced stepping and software single-step cannot |
| 538 | currently be used in combination, although with some care I think |
| 539 | they could be made to. Software single-step works by placing |
| 540 | breakpoints on all possible subsequent instructions; if the |
| 541 | displaced instruction is a PC-relative jump, those breakpoints |
| 542 | could fall in very strange places --- on pages that aren't |
| 543 | executable, or at addresses that are not proper instruction |
| 544 | boundaries. (We do generally let other threads run while we wait |
| 545 | to hit the software single-step breakpoint, and they might |
| 546 | encounter such a corrupted instruction.) One way to work around |
| 547 | this would be to have gdbarch_displaced_step_copy_insn fully |
| 548 | simulate the effect of PC-relative instructions (and return NULL) |
| 549 | on architectures that use software single-stepping. |
| 550 | |
| 551 | In non-stop mode, we can have independent and simultaneous step |
| 552 | requests, so more than one thread may need to simultaneously step |
| 553 | over a breakpoint. The current implementation assumes there is |
| 554 | only one scratch space per process. In this case, we have to |
| 555 | serialize access to the scratch space. If thread A wants to step |
| 556 | over a breakpoint, but we are currently waiting for some other |
| 557 | thread to complete a displaced step, we leave thread A stopped and |
| 558 | place it in the displaced_step_request_queue. Whenever a displaced |
| 559 | step finishes, we pick the next thread in the queue and start a new |
| 560 | displaced step operation on it. See displaced_step_prepare and |
| 561 | displaced_step_fixup for details. */ |
| 562 | |
| 563 | /* If this is not null_ptid, this is the thread carrying out a |
| 564 | displaced single-step. This thread's state will require fixing up |
| 565 | once it has completed its step. */ |
| 566 | static ptid_t displaced_step_ptid; |
| 567 | |
| 568 | struct displaced_step_request |
| 569 | { |
| 570 | ptid_t ptid; |
| 571 | struct displaced_step_request *next; |
| 572 | }; |
| 573 | |
| 574 | /* A queue of pending displaced stepping requests. */ |
| 575 | struct displaced_step_request *displaced_step_request_queue; |
| 576 | |
| 577 | /* The architecture the thread had when we stepped it. */ |
| 578 | static struct gdbarch *displaced_step_gdbarch; |
| 579 | |
| 580 | /* The closure provided gdbarch_displaced_step_copy_insn, to be used |
| 581 | for post-step cleanup. */ |
| 582 | static struct displaced_step_closure *displaced_step_closure; |
| 583 | |
| 584 | /* The address of the original instruction, and the copy we made. */ |
| 585 | static CORE_ADDR displaced_step_original, displaced_step_copy; |
| 586 | |
| 587 | /* Saved contents of copy area. */ |
| 588 | static gdb_byte *displaced_step_saved_copy; |
| 589 | |
| 590 | /* When this is non-zero, we are allowed to use displaced stepping, if |
| 591 | the architecture supports it. When this is zero, we use |
| 592 | traditional the hold-and-step approach. */ |
| 593 | int can_use_displaced_stepping = 1; |
| 594 | static void |
| 595 | show_can_use_displaced_stepping (struct ui_file *file, int from_tty, |
| 596 | struct cmd_list_element *c, |
| 597 | const char *value) |
| 598 | { |
| 599 | fprintf_filtered (file, _("\ |
| 600 | Debugger's willingness to use displaced stepping to step over " |
| 601 | "breakpoints is %s.\n"), value); |
| 602 | } |
| 603 | |
| 604 | /* Return non-zero if displaced stepping is enabled, and can be used |
| 605 | with GDBARCH. */ |
| 606 | static int |
| 607 | use_displaced_stepping (struct gdbarch *gdbarch) |
| 608 | { |
| 609 | return (can_use_displaced_stepping |
| 610 | && gdbarch_displaced_step_copy_insn_p (gdbarch)); |
| 611 | } |
| 612 | |
| 613 | /* Clean out any stray displaced stepping state. */ |
| 614 | static void |
| 615 | displaced_step_clear (void) |
| 616 | { |
| 617 | /* Indicate that there is no cleanup pending. */ |
| 618 | displaced_step_ptid = null_ptid; |
| 619 | |
| 620 | if (displaced_step_closure) |
| 621 | { |
| 622 | gdbarch_displaced_step_free_closure (displaced_step_gdbarch, |
| 623 | displaced_step_closure); |
| 624 | displaced_step_closure = NULL; |
| 625 | } |
| 626 | } |
| 627 | |
| 628 | static void |
| 629 | cleanup_displaced_step_closure (void *ptr) |
| 630 | { |
| 631 | struct displaced_step_closure *closure = ptr; |
| 632 | |
| 633 | gdbarch_displaced_step_free_closure (current_gdbarch, closure); |
| 634 | } |
| 635 | |
| 636 | /* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */ |
| 637 | void |
| 638 | displaced_step_dump_bytes (struct ui_file *file, |
| 639 | const gdb_byte *buf, |
| 640 | size_t len) |
| 641 | { |
| 642 | int i; |
| 643 | |
| 644 | for (i = 0; i < len; i++) |
| 645 | fprintf_unfiltered (file, "%02x ", buf[i]); |
| 646 | fputs_unfiltered ("\n", file); |
| 647 | } |
| 648 | |
| 649 | /* Prepare to single-step, using displaced stepping. |
| 650 | |
| 651 | Note that we cannot use displaced stepping when we have a signal to |
| 652 | deliver. If we have a signal to deliver and an instruction to step |
| 653 | over, then after the step, there will be no indication from the |
| 654 | target whether the thread entered a signal handler or ignored the |
| 655 | signal and stepped over the instruction successfully --- both cases |
| 656 | result in a simple SIGTRAP. In the first case we mustn't do a |
| 657 | fixup, and in the second case we must --- but we can't tell which. |
| 658 | Comments in the code for 'random signals' in handle_inferior_event |
| 659 | explain how we handle this case instead. |
| 660 | |
| 661 | Returns 1 if preparing was successful -- this thread is going to be |
| 662 | stepped now; or 0 if displaced stepping this thread got queued. */ |
| 663 | static int |
| 664 | displaced_step_prepare (ptid_t ptid) |
| 665 | { |
| 666 | struct cleanup *old_cleanups; |
| 667 | struct regcache *regcache = get_thread_regcache (ptid); |
| 668 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 669 | CORE_ADDR original, copy; |
| 670 | ULONGEST len; |
| 671 | struct displaced_step_closure *closure; |
| 672 | |
| 673 | /* We should never reach this function if the architecture does not |
| 674 | support displaced stepping. */ |
| 675 | gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch)); |
| 676 | |
| 677 | /* For the first cut, we're displaced stepping one thread at a |
| 678 | time. */ |
| 679 | |
| 680 | if (!ptid_equal (displaced_step_ptid, null_ptid)) |
| 681 | { |
| 682 | /* Already waiting for a displaced step to finish. Defer this |
| 683 | request and place in queue. */ |
| 684 | struct displaced_step_request *req, *new_req; |
| 685 | |
| 686 | if (debug_displaced) |
| 687 | fprintf_unfiltered (gdb_stdlog, |
| 688 | "displaced: defering step of %s\n", |
| 689 | target_pid_to_str (ptid)); |
| 690 | |
| 691 | new_req = xmalloc (sizeof (*new_req)); |
| 692 | new_req->ptid = ptid; |
| 693 | new_req->next = NULL; |
| 694 | |
| 695 | if (displaced_step_request_queue) |
| 696 | { |
| 697 | for (req = displaced_step_request_queue; |
| 698 | req && req->next; |
| 699 | req = req->next) |
| 700 | ; |
| 701 | req->next = new_req; |
| 702 | } |
| 703 | else |
| 704 | displaced_step_request_queue = new_req; |
| 705 | |
| 706 | return 0; |
| 707 | } |
| 708 | else |
| 709 | { |
| 710 | if (debug_displaced) |
| 711 | fprintf_unfiltered (gdb_stdlog, |
| 712 | "displaced: stepping %s now\n", |
| 713 | target_pid_to_str (ptid)); |
| 714 | } |
| 715 | |
| 716 | displaced_step_clear (); |
| 717 | |
| 718 | original = regcache_read_pc (regcache); |
| 719 | |
| 720 | copy = gdbarch_displaced_step_location (gdbarch); |
| 721 | len = gdbarch_max_insn_length (gdbarch); |
| 722 | |
| 723 | /* Save the original contents of the copy area. */ |
| 724 | displaced_step_saved_copy = xmalloc (len); |
| 725 | old_cleanups = make_cleanup (free_current_contents, |
| 726 | &displaced_step_saved_copy); |
| 727 | read_memory (copy, displaced_step_saved_copy, len); |
| 728 | if (debug_displaced) |
| 729 | { |
| 730 | fprintf_unfiltered (gdb_stdlog, "displaced: saved 0x%s: ", |
| 731 | paddr_nz (copy)); |
| 732 | displaced_step_dump_bytes (gdb_stdlog, displaced_step_saved_copy, len); |
| 733 | }; |
| 734 | |
| 735 | closure = gdbarch_displaced_step_copy_insn (gdbarch, |
| 736 | original, copy, regcache); |
| 737 | |
| 738 | /* We don't support the fully-simulated case at present. */ |
| 739 | gdb_assert (closure); |
| 740 | |
| 741 | make_cleanup (cleanup_displaced_step_closure, closure); |
| 742 | |
| 743 | /* Resume execution at the copy. */ |
| 744 | regcache_write_pc (regcache, copy); |
| 745 | |
| 746 | discard_cleanups (old_cleanups); |
| 747 | |
| 748 | if (debug_displaced) |
| 749 | fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to 0x%s\n", |
| 750 | paddr_nz (copy)); |
| 751 | |
| 752 | /* Save the information we need to fix things up if the step |
| 753 | succeeds. */ |
| 754 | displaced_step_ptid = ptid; |
| 755 | displaced_step_gdbarch = gdbarch; |
| 756 | displaced_step_closure = closure; |
| 757 | displaced_step_original = original; |
| 758 | displaced_step_copy = copy; |
| 759 | return 1; |
| 760 | } |
| 761 | |
| 762 | static void |
| 763 | displaced_step_clear_cleanup (void *ignore) |
| 764 | { |
| 765 | displaced_step_clear (); |
| 766 | } |
| 767 | |
| 768 | static void |
| 769 | write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr, const gdb_byte *myaddr, int len) |
| 770 | { |
| 771 | struct cleanup *ptid_cleanup = save_inferior_ptid (); |
| 772 | inferior_ptid = ptid; |
| 773 | write_memory (memaddr, myaddr, len); |
| 774 | do_cleanups (ptid_cleanup); |
| 775 | } |
| 776 | |
| 777 | static void |
| 778 | displaced_step_fixup (ptid_t event_ptid, enum target_signal signal) |
| 779 | { |
| 780 | struct cleanup *old_cleanups; |
| 781 | |
| 782 | /* Was this event for the pid we displaced? */ |
| 783 | if (ptid_equal (displaced_step_ptid, null_ptid) |
| 784 | || ! ptid_equal (displaced_step_ptid, event_ptid)) |
| 785 | return; |
| 786 | |
| 787 | old_cleanups = make_cleanup (displaced_step_clear_cleanup, 0); |
| 788 | |
| 789 | /* Restore the contents of the copy area. */ |
| 790 | { |
| 791 | ULONGEST len = gdbarch_max_insn_length (displaced_step_gdbarch); |
| 792 | write_memory_ptid (displaced_step_ptid, displaced_step_copy, |
| 793 | displaced_step_saved_copy, len); |
| 794 | if (debug_displaced) |
| 795 | fprintf_unfiltered (gdb_stdlog, "displaced: restored 0x%s\n", |
| 796 | paddr_nz (displaced_step_copy)); |
| 797 | } |
| 798 | |
| 799 | /* Did the instruction complete successfully? */ |
| 800 | if (signal == TARGET_SIGNAL_TRAP) |
| 801 | { |
| 802 | /* Fix up the resulting state. */ |
| 803 | gdbarch_displaced_step_fixup (displaced_step_gdbarch, |
| 804 | displaced_step_closure, |
| 805 | displaced_step_original, |
| 806 | displaced_step_copy, |
| 807 | get_thread_regcache (displaced_step_ptid)); |
| 808 | } |
| 809 | else |
| 810 | { |
| 811 | /* Since the instruction didn't complete, all we can do is |
| 812 | relocate the PC. */ |
| 813 | struct regcache *regcache = get_thread_regcache (event_ptid); |
| 814 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 815 | pc = displaced_step_original + (pc - displaced_step_copy); |
| 816 | regcache_write_pc (regcache, pc); |
| 817 | } |
| 818 | |
| 819 | do_cleanups (old_cleanups); |
| 820 | |
| 821 | /* Are there any pending displaced stepping requests? If so, run |
| 822 | one now. */ |
| 823 | if (displaced_step_request_queue) |
| 824 | { |
| 825 | struct displaced_step_request *head; |
| 826 | ptid_t ptid; |
| 827 | |
| 828 | head = displaced_step_request_queue; |
| 829 | ptid = head->ptid; |
| 830 | displaced_step_request_queue = head->next; |
| 831 | xfree (head); |
| 832 | |
| 833 | if (debug_displaced) |
| 834 | fprintf_unfiltered (gdb_stdlog, |
| 835 | "displaced: stepping queued %s now\n", |
| 836 | target_pid_to_str (ptid)); |
| 837 | |
| 838 | |
| 839 | displaced_step_ptid = null_ptid; |
| 840 | displaced_step_prepare (ptid); |
| 841 | target_resume (ptid, 1, TARGET_SIGNAL_0); |
| 842 | } |
| 843 | } |
| 844 | |
| 845 | \f |
| 846 | /* Resuming. */ |
| 847 | |
| 848 | /* Things to clean up if we QUIT out of resume (). */ |
| 849 | static void |
| 850 | resume_cleanups (void *ignore) |
| 851 | { |
| 852 | normal_stop (); |
| 853 | } |
| 854 | |
| 855 | static const char schedlock_off[] = "off"; |
| 856 | static const char schedlock_on[] = "on"; |
| 857 | static const char schedlock_step[] = "step"; |
| 858 | static const char *scheduler_enums[] = { |
| 859 | schedlock_off, |
| 860 | schedlock_on, |
| 861 | schedlock_step, |
| 862 | NULL |
| 863 | }; |
| 864 | static const char *scheduler_mode = schedlock_off; |
| 865 | static void |
| 866 | show_scheduler_mode (struct ui_file *file, int from_tty, |
| 867 | struct cmd_list_element *c, const char *value) |
| 868 | { |
| 869 | fprintf_filtered (file, _("\ |
| 870 | Mode for locking scheduler during execution is \"%s\".\n"), |
| 871 | value); |
| 872 | } |
| 873 | |
| 874 | static void |
| 875 | set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c) |
| 876 | { |
| 877 | if (!target_can_lock_scheduler) |
| 878 | { |
| 879 | scheduler_mode = schedlock_off; |
| 880 | error (_("Target '%s' cannot support this command."), target_shortname); |
| 881 | } |
| 882 | } |
| 883 | |
| 884 | |
| 885 | /* Resume the inferior, but allow a QUIT. This is useful if the user |
| 886 | wants to interrupt some lengthy single-stepping operation |
| 887 | (for child processes, the SIGINT goes to the inferior, and so |
| 888 | we get a SIGINT random_signal, but for remote debugging and perhaps |
| 889 | other targets, that's not true). |
| 890 | |
| 891 | STEP nonzero if we should step (zero to continue instead). |
| 892 | SIG is the signal to give the inferior (zero for none). */ |
| 893 | void |
| 894 | resume (int step, enum target_signal sig) |
| 895 | { |
| 896 | int should_resume = 1; |
| 897 | struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0); |
| 898 | struct regcache *regcache = get_current_regcache (); |
| 899 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 900 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 901 | QUIT; |
| 902 | |
| 903 | if (debug_infrun) |
| 904 | fprintf_unfiltered (gdb_stdlog, |
| 905 | "infrun: resume (step=%d, signal=%d), " |
| 906 | "stepping_over_breakpoint=%d\n", |
| 907 | step, sig, stepping_over_breakpoint); |
| 908 | |
| 909 | /* Some targets (e.g. Solaris x86) have a kernel bug when stepping |
| 910 | over an instruction that causes a page fault without triggering |
| 911 | a hardware watchpoint. The kernel properly notices that it shouldn't |
| 912 | stop, because the hardware watchpoint is not triggered, but it forgets |
| 913 | the step request and continues the program normally. |
| 914 | Work around the problem by removing hardware watchpoints if a step is |
| 915 | requested, GDB will check for a hardware watchpoint trigger after the |
| 916 | step anyway. */ |
| 917 | if (CANNOT_STEP_HW_WATCHPOINTS && step) |
| 918 | remove_hw_watchpoints (); |
| 919 | |
| 920 | |
| 921 | /* Normally, by the time we reach `resume', the breakpoints are either |
| 922 | removed or inserted, as appropriate. The exception is if we're sitting |
| 923 | at a permanent breakpoint; we need to step over it, but permanent |
| 924 | breakpoints can't be removed. So we have to test for it here. */ |
| 925 | if (breakpoint_here_p (pc) == permanent_breakpoint_here) |
| 926 | { |
| 927 | if (gdbarch_skip_permanent_breakpoint_p (gdbarch)) |
| 928 | gdbarch_skip_permanent_breakpoint (gdbarch, regcache); |
| 929 | else |
| 930 | error (_("\ |
| 931 | The program is stopped at a permanent breakpoint, but GDB does not know\n\ |
| 932 | how to step past a permanent breakpoint on this architecture. Try using\n\ |
| 933 | a command like `return' or `jump' to continue execution.")); |
| 934 | } |
| 935 | |
| 936 | /* If enabled, step over breakpoints by executing a copy of the |
| 937 | instruction at a different address. |
| 938 | |
| 939 | We can't use displaced stepping when we have a signal to deliver; |
| 940 | the comments for displaced_step_prepare explain why. The |
| 941 | comments in the handle_inferior event for dealing with 'random |
| 942 | signals' explain what we do instead. */ |
| 943 | if (use_displaced_stepping (gdbarch) |
| 944 | && stepping_over_breakpoint |
| 945 | && sig == TARGET_SIGNAL_0) |
| 946 | { |
| 947 | if (!displaced_step_prepare (inferior_ptid)) |
| 948 | /* Got placed in displaced stepping queue. Will be resumed |
| 949 | later when all the currently queued displaced stepping |
| 950 | requests finish. */ |
| 951 | return; |
| 952 | } |
| 953 | |
| 954 | if (step && gdbarch_software_single_step_p (gdbarch)) |
| 955 | { |
| 956 | /* Do it the hard way, w/temp breakpoints */ |
| 957 | if (gdbarch_software_single_step (gdbarch, get_current_frame ())) |
| 958 | { |
| 959 | /* ...and don't ask hardware to do it. */ |
| 960 | step = 0; |
| 961 | /* and do not pull these breakpoints until after a `wait' in |
| 962 | `wait_for_inferior' */ |
| 963 | singlestep_breakpoints_inserted_p = 1; |
| 964 | singlestep_ptid = inferior_ptid; |
| 965 | singlestep_pc = pc; |
| 966 | } |
| 967 | } |
| 968 | |
| 969 | /* If there were any forks/vforks/execs that were caught and are |
| 970 | now to be followed, then do so. */ |
| 971 | switch (pending_follow.kind) |
| 972 | { |
| 973 | case TARGET_WAITKIND_FORKED: |
| 974 | case TARGET_WAITKIND_VFORKED: |
| 975 | pending_follow.kind = TARGET_WAITKIND_SPURIOUS; |
| 976 | if (follow_fork ()) |
| 977 | should_resume = 0; |
| 978 | break; |
| 979 | |
| 980 | case TARGET_WAITKIND_EXECD: |
| 981 | /* follow_exec is called as soon as the exec event is seen. */ |
| 982 | pending_follow.kind = TARGET_WAITKIND_SPURIOUS; |
| 983 | break; |
| 984 | |
| 985 | default: |
| 986 | break; |
| 987 | } |
| 988 | |
| 989 | /* Install inferior's terminal modes. */ |
| 990 | target_terminal_inferior (); |
| 991 | |
| 992 | if (should_resume) |
| 993 | { |
| 994 | ptid_t resume_ptid; |
| 995 | |
| 996 | resume_ptid = RESUME_ALL; /* Default */ |
| 997 | |
| 998 | /* If STEP is set, it's a request to use hardware stepping |
| 999 | facilities. But in that case, we should never |
| 1000 | use singlestep breakpoint. */ |
| 1001 | gdb_assert (!(singlestep_breakpoints_inserted_p && step)); |
| 1002 | |
| 1003 | if (singlestep_breakpoints_inserted_p |
| 1004 | && stepping_past_singlestep_breakpoint) |
| 1005 | { |
| 1006 | /* The situation here is as follows. In thread T1 we wanted to |
| 1007 | single-step. Lacking hardware single-stepping we've |
| 1008 | set breakpoint at the PC of the next instruction -- call it |
| 1009 | P. After resuming, we've hit that breakpoint in thread T2. |
| 1010 | Now we've removed original breakpoint, inserted breakpoint |
| 1011 | at P+1, and try to step to advance T2 past breakpoint. |
| 1012 | We need to step only T2, as if T1 is allowed to freely run, |
| 1013 | it can run past P, and if other threads are allowed to run, |
| 1014 | they can hit breakpoint at P+1, and nested hits of single-step |
| 1015 | breakpoints is not something we'd want -- that's complicated |
| 1016 | to support, and has no value. */ |
| 1017 | resume_ptid = inferior_ptid; |
| 1018 | } |
| 1019 | |
| 1020 | if ((step || singlestep_breakpoints_inserted_p) |
| 1021 | && stepping_over_breakpoint) |
| 1022 | { |
| 1023 | /* We're allowing a thread to run past a breakpoint it has |
| 1024 | hit, by single-stepping the thread with the breakpoint |
| 1025 | removed. In which case, we need to single-step only this |
| 1026 | thread, and keep others stopped, as they can miss this |
| 1027 | breakpoint if allowed to run. |
| 1028 | |
| 1029 | The current code actually removes all breakpoints when |
| 1030 | doing this, not just the one being stepped over, so if we |
| 1031 | let other threads run, we can actually miss any |
| 1032 | breakpoint, not just the one at PC. */ |
| 1033 | resume_ptid = inferior_ptid; |
| 1034 | } |
| 1035 | |
| 1036 | if ((scheduler_mode == schedlock_on) |
| 1037 | || (scheduler_mode == schedlock_step |
| 1038 | && (step || singlestep_breakpoints_inserted_p))) |
| 1039 | { |
| 1040 | /* User-settable 'scheduler' mode requires solo thread resume. */ |
| 1041 | resume_ptid = inferior_ptid; |
| 1042 | } |
| 1043 | |
| 1044 | if (gdbarch_cannot_step_breakpoint (gdbarch)) |
| 1045 | { |
| 1046 | /* Most targets can step a breakpoint instruction, thus |
| 1047 | executing it normally. But if this one cannot, just |
| 1048 | continue and we will hit it anyway. */ |
| 1049 | if (step && breakpoint_inserted_here_p (pc)) |
| 1050 | step = 0; |
| 1051 | } |
| 1052 | |
| 1053 | if (debug_displaced |
| 1054 | && use_displaced_stepping (gdbarch) |
| 1055 | && stepping_over_breakpoint) |
| 1056 | { |
| 1057 | struct regcache *resume_regcache = get_thread_regcache (resume_ptid); |
| 1058 | CORE_ADDR actual_pc = regcache_read_pc (resume_regcache); |
| 1059 | gdb_byte buf[4]; |
| 1060 | |
| 1061 | fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ", |
| 1062 | paddr_nz (actual_pc)); |
| 1063 | read_memory (actual_pc, buf, sizeof (buf)); |
| 1064 | displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf)); |
| 1065 | } |
| 1066 | |
| 1067 | target_resume (resume_ptid, step, sig); |
| 1068 | } |
| 1069 | |
| 1070 | discard_cleanups (old_cleanups); |
| 1071 | } |
| 1072 | \f |
| 1073 | /* Proceeding. */ |
| 1074 | |
| 1075 | /* Clear out all variables saying what to do when inferior is continued. |
| 1076 | First do this, then set the ones you want, then call `proceed'. */ |
| 1077 | |
| 1078 | void |
| 1079 | clear_proceed_status (void) |
| 1080 | { |
| 1081 | stepping_over_breakpoint = 0; |
| 1082 | step_range_start = 0; |
| 1083 | step_range_end = 0; |
| 1084 | step_frame_id = null_frame_id; |
| 1085 | step_over_calls = STEP_OVER_UNDEBUGGABLE; |
| 1086 | stop_after_trap = 0; |
| 1087 | stop_soon = NO_STOP_QUIETLY; |
| 1088 | proceed_to_finish = 0; |
| 1089 | breakpoint_proceeded = 1; /* We're about to proceed... */ |
| 1090 | |
| 1091 | if (stop_registers) |
| 1092 | { |
| 1093 | regcache_xfree (stop_registers); |
| 1094 | stop_registers = NULL; |
| 1095 | } |
| 1096 | |
| 1097 | /* Discard any remaining commands or status from previous stop. */ |
| 1098 | bpstat_clear (&stop_bpstat); |
| 1099 | } |
| 1100 | |
| 1101 | /* This should be suitable for any targets that support threads. */ |
| 1102 | |
| 1103 | static int |
| 1104 | prepare_to_proceed (int step) |
| 1105 | { |
| 1106 | ptid_t wait_ptid; |
| 1107 | struct target_waitstatus wait_status; |
| 1108 | |
| 1109 | /* Get the last target status returned by target_wait(). */ |
| 1110 | get_last_target_status (&wait_ptid, &wait_status); |
| 1111 | |
| 1112 | /* Make sure we were stopped at a breakpoint. */ |
| 1113 | if (wait_status.kind != TARGET_WAITKIND_STOPPED |
| 1114 | || wait_status.value.sig != TARGET_SIGNAL_TRAP) |
| 1115 | { |
| 1116 | return 0; |
| 1117 | } |
| 1118 | |
| 1119 | /* Switched over from WAIT_PID. */ |
| 1120 | if (!ptid_equal (wait_ptid, minus_one_ptid) |
| 1121 | && !ptid_equal (inferior_ptid, wait_ptid)) |
| 1122 | { |
| 1123 | struct regcache *regcache = get_thread_regcache (wait_ptid); |
| 1124 | |
| 1125 | if (breakpoint_here_p (regcache_read_pc (regcache))) |
| 1126 | { |
| 1127 | /* If stepping, remember current thread to switch back to. */ |
| 1128 | if (step) |
| 1129 | deferred_step_ptid = inferior_ptid; |
| 1130 | |
| 1131 | /* Switch back to WAIT_PID thread. */ |
| 1132 | switch_to_thread (wait_ptid); |
| 1133 | |
| 1134 | /* We return 1 to indicate that there is a breakpoint here, |
| 1135 | so we need to step over it before continuing to avoid |
| 1136 | hitting it straight away. */ |
| 1137 | return 1; |
| 1138 | } |
| 1139 | } |
| 1140 | |
| 1141 | return 0; |
| 1142 | } |
| 1143 | |
| 1144 | /* Record the pc of the program the last time it stopped. This is |
| 1145 | just used internally by wait_for_inferior, but need to be preserved |
| 1146 | over calls to it and cleared when the inferior is started. */ |
| 1147 | static CORE_ADDR prev_pc; |
| 1148 | |
| 1149 | /* Basic routine for continuing the program in various fashions. |
| 1150 | |
| 1151 | ADDR is the address to resume at, or -1 for resume where stopped. |
| 1152 | SIGGNAL is the signal to give it, or 0 for none, |
| 1153 | or -1 for act according to how it stopped. |
| 1154 | STEP is nonzero if should trap after one instruction. |
| 1155 | -1 means return after that and print nothing. |
| 1156 | You should probably set various step_... variables |
| 1157 | before calling here, if you are stepping. |
| 1158 | |
| 1159 | You should call clear_proceed_status before calling proceed. */ |
| 1160 | |
| 1161 | void |
| 1162 | proceed (CORE_ADDR addr, enum target_signal siggnal, int step) |
| 1163 | { |
| 1164 | struct regcache *regcache = get_current_regcache (); |
| 1165 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 1166 | CORE_ADDR pc = regcache_read_pc (regcache); |
| 1167 | int oneproc = 0; |
| 1168 | |
| 1169 | if (step > 0) |
| 1170 | step_start_function = find_pc_function (pc); |
| 1171 | if (step < 0) |
| 1172 | stop_after_trap = 1; |
| 1173 | |
| 1174 | if (addr == (CORE_ADDR) -1) |
| 1175 | { |
| 1176 | if (pc == stop_pc && breakpoint_here_p (pc)) |
| 1177 | /* There is a breakpoint at the address we will resume at, |
| 1178 | step one instruction before inserting breakpoints so that |
| 1179 | we do not stop right away (and report a second hit at this |
| 1180 | breakpoint). */ |
| 1181 | oneproc = 1; |
| 1182 | else if (gdbarch_single_step_through_delay_p (gdbarch) |
| 1183 | && gdbarch_single_step_through_delay (gdbarch, |
| 1184 | get_current_frame ())) |
| 1185 | /* We stepped onto an instruction that needs to be stepped |
| 1186 | again before re-inserting the breakpoint, do so. */ |
| 1187 | oneproc = 1; |
| 1188 | } |
| 1189 | else |
| 1190 | { |
| 1191 | regcache_write_pc (regcache, addr); |
| 1192 | } |
| 1193 | |
| 1194 | if (debug_infrun) |
| 1195 | fprintf_unfiltered (gdb_stdlog, |
| 1196 | "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n", |
| 1197 | paddr_nz (addr), siggnal, step); |
| 1198 | |
| 1199 | /* In a multi-threaded task we may select another thread |
| 1200 | and then continue or step. |
| 1201 | |
| 1202 | But if the old thread was stopped at a breakpoint, it |
| 1203 | will immediately cause another breakpoint stop without |
| 1204 | any execution (i.e. it will report a breakpoint hit |
| 1205 | incorrectly). So we must step over it first. |
| 1206 | |
| 1207 | prepare_to_proceed checks the current thread against the thread |
| 1208 | that reported the most recent event. If a step-over is required |
| 1209 | it returns TRUE and sets the current thread to the old thread. */ |
| 1210 | if (prepare_to_proceed (step)) |
| 1211 | oneproc = 1; |
| 1212 | |
| 1213 | if (oneproc) |
| 1214 | { |
| 1215 | stepping_over_breakpoint = 1; |
| 1216 | /* If displaced stepping is enabled, we can step over the |
| 1217 | breakpoint without hitting it, so leave all breakpoints |
| 1218 | inserted. Otherwise we need to disable all breakpoints, step |
| 1219 | one instruction, and then re-add them when that step is |
| 1220 | finished. */ |
| 1221 | if (!use_displaced_stepping (gdbarch)) |
| 1222 | remove_breakpoints (); |
| 1223 | } |
| 1224 | |
| 1225 | /* We can insert breakpoints if we're not trying to step over one, |
| 1226 | or if we are stepping over one but we're using displaced stepping |
| 1227 | to do so. */ |
| 1228 | if (! stepping_over_breakpoint || use_displaced_stepping (gdbarch)) |
| 1229 | insert_breakpoints (); |
| 1230 | |
| 1231 | if (siggnal != TARGET_SIGNAL_DEFAULT) |
| 1232 | stop_signal = siggnal; |
| 1233 | /* If this signal should not be seen by program, |
| 1234 | give it zero. Used for debugging signals. */ |
| 1235 | else if (!signal_program[stop_signal]) |
| 1236 | stop_signal = TARGET_SIGNAL_0; |
| 1237 | |
| 1238 | annotate_starting (); |
| 1239 | |
| 1240 | /* Make sure that output from GDB appears before output from the |
| 1241 | inferior. */ |
| 1242 | gdb_flush (gdb_stdout); |
| 1243 | |
| 1244 | /* Refresh prev_pc value just prior to resuming. This used to be |
| 1245 | done in stop_stepping, however, setting prev_pc there did not handle |
| 1246 | scenarios such as inferior function calls or returning from |
| 1247 | a function via the return command. In those cases, the prev_pc |
| 1248 | value was not set properly for subsequent commands. The prev_pc value |
| 1249 | is used to initialize the starting line number in the ecs. With an |
| 1250 | invalid value, the gdb next command ends up stopping at the position |
| 1251 | represented by the next line table entry past our start position. |
| 1252 | On platforms that generate one line table entry per line, this |
| 1253 | is not a problem. However, on the ia64, the compiler generates |
| 1254 | extraneous line table entries that do not increase the line number. |
| 1255 | When we issue the gdb next command on the ia64 after an inferior call |
| 1256 | or a return command, we often end up a few instructions forward, still |
| 1257 | within the original line we started. |
| 1258 | |
| 1259 | An attempt was made to have init_execution_control_state () refresh |
| 1260 | the prev_pc value before calculating the line number. This approach |
| 1261 | did not work because on platforms that use ptrace, the pc register |
| 1262 | cannot be read unless the inferior is stopped. At that point, we |
| 1263 | are not guaranteed the inferior is stopped and so the regcache_read_pc () |
| 1264 | call can fail. Setting the prev_pc value here ensures the value is |
| 1265 | updated correctly when the inferior is stopped. */ |
| 1266 | prev_pc = regcache_read_pc (get_current_regcache ()); |
| 1267 | |
| 1268 | /* Resume inferior. */ |
| 1269 | resume (oneproc || step || bpstat_should_step (), stop_signal); |
| 1270 | |
| 1271 | /* Wait for it to stop (if not standalone) |
| 1272 | and in any case decode why it stopped, and act accordingly. */ |
| 1273 | /* Do this only if we are not using the event loop, or if the target |
| 1274 | does not support asynchronous execution. */ |
| 1275 | if (!target_can_async_p ()) |
| 1276 | { |
| 1277 | wait_for_inferior (0); |
| 1278 | normal_stop (); |
| 1279 | } |
| 1280 | } |
| 1281 | \f |
| 1282 | |
| 1283 | /* Start remote-debugging of a machine over a serial link. */ |
| 1284 | |
| 1285 | void |
| 1286 | start_remote (int from_tty) |
| 1287 | { |
| 1288 | init_wait_for_inferior (); |
| 1289 | stop_soon = STOP_QUIETLY_REMOTE; |
| 1290 | stepping_over_breakpoint = 0; |
| 1291 | |
| 1292 | /* Always go on waiting for the target, regardless of the mode. */ |
| 1293 | /* FIXME: cagney/1999-09-23: At present it isn't possible to |
| 1294 | indicate to wait_for_inferior that a target should timeout if |
| 1295 | nothing is returned (instead of just blocking). Because of this, |
| 1296 | targets expecting an immediate response need to, internally, set |
| 1297 | things up so that the target_wait() is forced to eventually |
| 1298 | timeout. */ |
| 1299 | /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to |
| 1300 | differentiate to its caller what the state of the target is after |
| 1301 | the initial open has been performed. Here we're assuming that |
| 1302 | the target has stopped. It should be possible to eventually have |
| 1303 | target_open() return to the caller an indication that the target |
| 1304 | is currently running and GDB state should be set to the same as |
| 1305 | for an async run. */ |
| 1306 | wait_for_inferior (0); |
| 1307 | |
| 1308 | /* Now that the inferior has stopped, do any bookkeeping like |
| 1309 | loading shared libraries. We want to do this before normal_stop, |
| 1310 | so that the displayed frame is up to date. */ |
| 1311 | post_create_inferior (¤t_target, from_tty); |
| 1312 | |
| 1313 | normal_stop (); |
| 1314 | } |
| 1315 | |
| 1316 | /* Initialize static vars when a new inferior begins. */ |
| 1317 | |
| 1318 | void |
| 1319 | init_wait_for_inferior (void) |
| 1320 | { |
| 1321 | /* These are meaningless until the first time through wait_for_inferior. */ |
| 1322 | prev_pc = 0; |
| 1323 | |
| 1324 | breakpoint_init_inferior (inf_starting); |
| 1325 | |
| 1326 | /* Don't confuse first call to proceed(). */ |
| 1327 | stop_signal = TARGET_SIGNAL_0; |
| 1328 | |
| 1329 | /* The first resume is not following a fork/vfork/exec. */ |
| 1330 | pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */ |
| 1331 | |
| 1332 | clear_proceed_status (); |
| 1333 | |
| 1334 | stepping_past_singlestep_breakpoint = 0; |
| 1335 | deferred_step_ptid = null_ptid; |
| 1336 | |
| 1337 | target_last_wait_ptid = minus_one_ptid; |
| 1338 | |
| 1339 | displaced_step_clear (); |
| 1340 | } |
| 1341 | |
| 1342 | \f |
| 1343 | /* This enum encodes possible reasons for doing a target_wait, so that |
| 1344 | wfi can call target_wait in one place. (Ultimately the call will be |
| 1345 | moved out of the infinite loop entirely.) */ |
| 1346 | |
| 1347 | enum infwait_states |
| 1348 | { |
| 1349 | infwait_normal_state, |
| 1350 | infwait_thread_hop_state, |
| 1351 | infwait_step_watch_state, |
| 1352 | infwait_nonstep_watch_state |
| 1353 | }; |
| 1354 | |
| 1355 | /* Why did the inferior stop? Used to print the appropriate messages |
| 1356 | to the interface from within handle_inferior_event(). */ |
| 1357 | enum inferior_stop_reason |
| 1358 | { |
| 1359 | /* Step, next, nexti, stepi finished. */ |
| 1360 | END_STEPPING_RANGE, |
| 1361 | /* Inferior terminated by signal. */ |
| 1362 | SIGNAL_EXITED, |
| 1363 | /* Inferior exited. */ |
| 1364 | EXITED, |
| 1365 | /* Inferior received signal, and user asked to be notified. */ |
| 1366 | SIGNAL_RECEIVED |
| 1367 | }; |
| 1368 | |
| 1369 | /* This structure contains what used to be local variables in |
| 1370 | wait_for_inferior. Probably many of them can return to being |
| 1371 | locals in handle_inferior_event. */ |
| 1372 | |
| 1373 | struct execution_control_state |
| 1374 | { |
| 1375 | struct target_waitstatus ws; |
| 1376 | struct target_waitstatus *wp; |
| 1377 | /* Should we step over breakpoint next time keep_going |
| 1378 | is called? */ |
| 1379 | int stepping_over_breakpoint; |
| 1380 | int random_signal; |
| 1381 | CORE_ADDR stop_func_start; |
| 1382 | CORE_ADDR stop_func_end; |
| 1383 | char *stop_func_name; |
| 1384 | struct symtab_and_line sal; |
| 1385 | int current_line; |
| 1386 | struct symtab *current_symtab; |
| 1387 | ptid_t ptid; |
| 1388 | ptid_t saved_inferior_ptid; |
| 1389 | int step_after_step_resume_breakpoint; |
| 1390 | int stepping_through_solib_after_catch; |
| 1391 | bpstat stepping_through_solib_catchpoints; |
| 1392 | int new_thread_event; |
| 1393 | struct target_waitstatus tmpstatus; |
| 1394 | enum infwait_states infwait_state; |
| 1395 | ptid_t waiton_ptid; |
| 1396 | int wait_some_more; |
| 1397 | }; |
| 1398 | |
| 1399 | void init_execution_control_state (struct execution_control_state *ecs); |
| 1400 | |
| 1401 | void handle_inferior_event (struct execution_control_state *ecs); |
| 1402 | |
| 1403 | static void step_into_function (struct execution_control_state *ecs); |
| 1404 | static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame); |
| 1405 | static void insert_step_resume_breakpoint_at_caller (struct frame_info *); |
| 1406 | static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal, |
| 1407 | struct frame_id sr_id); |
| 1408 | static void insert_longjmp_resume_breakpoint (CORE_ADDR); |
| 1409 | |
| 1410 | static void stop_stepping (struct execution_control_state *ecs); |
| 1411 | static void prepare_to_wait (struct execution_control_state *ecs); |
| 1412 | static void keep_going (struct execution_control_state *ecs); |
| 1413 | static void print_stop_reason (enum inferior_stop_reason stop_reason, |
| 1414 | int stop_info); |
| 1415 | |
| 1416 | /* Wait for control to return from inferior to debugger. |
| 1417 | |
| 1418 | If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals |
| 1419 | as if they were SIGTRAP signals. This can be useful during |
| 1420 | the startup sequence on some targets such as HP/UX, where |
| 1421 | we receive an EXEC event instead of the expected SIGTRAP. |
| 1422 | |
| 1423 | If inferior gets a signal, we may decide to start it up again |
| 1424 | instead of returning. That is why there is a loop in this function. |
| 1425 | When this function actually returns it means the inferior |
| 1426 | should be left stopped and GDB should read more commands. */ |
| 1427 | |
| 1428 | void |
| 1429 | wait_for_inferior (int treat_exec_as_sigtrap) |
| 1430 | { |
| 1431 | struct cleanup *old_cleanups; |
| 1432 | struct execution_control_state ecss; |
| 1433 | struct execution_control_state *ecs; |
| 1434 | |
| 1435 | if (debug_infrun) |
| 1436 | fprintf_unfiltered |
| 1437 | (gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n", |
| 1438 | treat_exec_as_sigtrap); |
| 1439 | |
| 1440 | old_cleanups = make_cleanup (delete_step_resume_breakpoint, |
| 1441 | &step_resume_breakpoint); |
| 1442 | |
| 1443 | /* wfi still stays in a loop, so it's OK just to take the address of |
| 1444 | a local to get the ecs pointer. */ |
| 1445 | ecs = &ecss; |
| 1446 | |
| 1447 | /* Fill in with reasonable starting values. */ |
| 1448 | init_execution_control_state (ecs); |
| 1449 | |
| 1450 | /* We'll update this if & when we switch to a new thread. */ |
| 1451 | previous_inferior_ptid = inferior_ptid; |
| 1452 | |
| 1453 | overlay_cache_invalid = 1; |
| 1454 | |
| 1455 | /* We have to invalidate the registers BEFORE calling target_wait |
| 1456 | because they can be loaded from the target while in target_wait. |
| 1457 | This makes remote debugging a bit more efficient for those |
| 1458 | targets that provide critical registers as part of their normal |
| 1459 | status mechanism. */ |
| 1460 | |
| 1461 | registers_changed (); |
| 1462 | |
| 1463 | while (1) |
| 1464 | { |
| 1465 | if (deprecated_target_wait_hook) |
| 1466 | ecs->ptid = deprecated_target_wait_hook (ecs->waiton_ptid, ecs->wp); |
| 1467 | else |
| 1468 | ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp); |
| 1469 | |
| 1470 | if (treat_exec_as_sigtrap && ecs->ws.kind == TARGET_WAITKIND_EXECD) |
| 1471 | { |
| 1472 | xfree (ecs->ws.value.execd_pathname); |
| 1473 | ecs->ws.kind = TARGET_WAITKIND_STOPPED; |
| 1474 | ecs->ws.value.sig = TARGET_SIGNAL_TRAP; |
| 1475 | } |
| 1476 | |
| 1477 | /* Now figure out what to do with the result of the result. */ |
| 1478 | handle_inferior_event (ecs); |
| 1479 | |
| 1480 | if (!ecs->wait_some_more) |
| 1481 | break; |
| 1482 | } |
| 1483 | do_cleanups (old_cleanups); |
| 1484 | } |
| 1485 | |
| 1486 | /* Asynchronous version of wait_for_inferior. It is called by the |
| 1487 | event loop whenever a change of state is detected on the file |
| 1488 | descriptor corresponding to the target. It can be called more than |
| 1489 | once to complete a single execution command. In such cases we need |
| 1490 | to keep the state in a global variable ASYNC_ECSS. If it is the |
| 1491 | last time that this function is called for a single execution |
| 1492 | command, then report to the user that the inferior has stopped, and |
| 1493 | do the necessary cleanups. */ |
| 1494 | |
| 1495 | struct execution_control_state async_ecss; |
| 1496 | struct execution_control_state *async_ecs; |
| 1497 | |
| 1498 | void |
| 1499 | fetch_inferior_event (void *client_data) |
| 1500 | { |
| 1501 | static struct cleanup *old_cleanups; |
| 1502 | |
| 1503 | async_ecs = &async_ecss; |
| 1504 | |
| 1505 | if (!async_ecs->wait_some_more) |
| 1506 | { |
| 1507 | /* Fill in with reasonable starting values. */ |
| 1508 | init_execution_control_state (async_ecs); |
| 1509 | |
| 1510 | /* We'll update this if & when we switch to a new thread. */ |
| 1511 | previous_inferior_ptid = inferior_ptid; |
| 1512 | |
| 1513 | overlay_cache_invalid = 1; |
| 1514 | |
| 1515 | /* We have to invalidate the registers BEFORE calling target_wait |
| 1516 | because they can be loaded from the target while in target_wait. |
| 1517 | This makes remote debugging a bit more efficient for those |
| 1518 | targets that provide critical registers as part of their normal |
| 1519 | status mechanism. */ |
| 1520 | |
| 1521 | registers_changed (); |
| 1522 | } |
| 1523 | |
| 1524 | if (deprecated_target_wait_hook) |
| 1525 | async_ecs->ptid = |
| 1526 | deprecated_target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp); |
| 1527 | else |
| 1528 | async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp); |
| 1529 | |
| 1530 | /* Now figure out what to do with the result of the result. */ |
| 1531 | handle_inferior_event (async_ecs); |
| 1532 | |
| 1533 | if (!async_ecs->wait_some_more) |
| 1534 | { |
| 1535 | delete_step_resume_breakpoint (&step_resume_breakpoint); |
| 1536 | |
| 1537 | normal_stop (); |
| 1538 | if (step_multi && stop_step) |
| 1539 | inferior_event_handler (INF_EXEC_CONTINUE, NULL); |
| 1540 | else |
| 1541 | inferior_event_handler (INF_EXEC_COMPLETE, NULL); |
| 1542 | } |
| 1543 | } |
| 1544 | |
| 1545 | /* Prepare an execution control state for looping through a |
| 1546 | wait_for_inferior-type loop. */ |
| 1547 | |
| 1548 | void |
| 1549 | init_execution_control_state (struct execution_control_state *ecs) |
| 1550 | { |
| 1551 | ecs->stepping_over_breakpoint = 0; |
| 1552 | ecs->random_signal = 0; |
| 1553 | ecs->step_after_step_resume_breakpoint = 0; |
| 1554 | ecs->stepping_through_solib_after_catch = 0; |
| 1555 | ecs->stepping_through_solib_catchpoints = NULL; |
| 1556 | ecs->sal = find_pc_line (prev_pc, 0); |
| 1557 | ecs->current_line = ecs->sal.line; |
| 1558 | ecs->current_symtab = ecs->sal.symtab; |
| 1559 | ecs->infwait_state = infwait_normal_state; |
| 1560 | ecs->waiton_ptid = pid_to_ptid (-1); |
| 1561 | ecs->wp = &(ecs->ws); |
| 1562 | } |
| 1563 | |
| 1564 | /* Return the cached copy of the last pid/waitstatus returned by |
| 1565 | target_wait()/deprecated_target_wait_hook(). The data is actually |
| 1566 | cached by handle_inferior_event(), which gets called immediately |
| 1567 | after target_wait()/deprecated_target_wait_hook(). */ |
| 1568 | |
| 1569 | void |
| 1570 | get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status) |
| 1571 | { |
| 1572 | *ptidp = target_last_wait_ptid; |
| 1573 | *status = target_last_waitstatus; |
| 1574 | } |
| 1575 | |
| 1576 | void |
| 1577 | nullify_last_target_wait_ptid (void) |
| 1578 | { |
| 1579 | target_last_wait_ptid = minus_one_ptid; |
| 1580 | } |
| 1581 | |
| 1582 | /* Switch thread contexts, maintaining "infrun state". */ |
| 1583 | |
| 1584 | static void |
| 1585 | context_switch (struct execution_control_state *ecs) |
| 1586 | { |
| 1587 | /* Caution: it may happen that the new thread (or the old one!) |
| 1588 | is not in the thread list. In this case we must not attempt |
| 1589 | to "switch context", or we run the risk that our context may |
| 1590 | be lost. This may happen as a result of the target module |
| 1591 | mishandling thread creation. */ |
| 1592 | |
| 1593 | if (debug_infrun) |
| 1594 | { |
| 1595 | fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ", |
| 1596 | target_pid_to_str (inferior_ptid)); |
| 1597 | fprintf_unfiltered (gdb_stdlog, "to %s\n", |
| 1598 | target_pid_to_str (ecs->ptid)); |
| 1599 | } |
| 1600 | |
| 1601 | if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid)) |
| 1602 | { /* Perform infrun state context switch: */ |
| 1603 | /* Save infrun state for the old thread. */ |
| 1604 | save_infrun_state (inferior_ptid, prev_pc, |
| 1605 | stepping_over_breakpoint, step_resume_breakpoint, |
| 1606 | step_range_start, |
| 1607 | step_range_end, &step_frame_id, |
| 1608 | ecs->stepping_over_breakpoint, |
| 1609 | ecs->stepping_through_solib_after_catch, |
| 1610 | ecs->stepping_through_solib_catchpoints, |
| 1611 | ecs->current_line, ecs->current_symtab); |
| 1612 | |
| 1613 | /* Load infrun state for the new thread. */ |
| 1614 | load_infrun_state (ecs->ptid, &prev_pc, |
| 1615 | &stepping_over_breakpoint, &step_resume_breakpoint, |
| 1616 | &step_range_start, |
| 1617 | &step_range_end, &step_frame_id, |
| 1618 | &ecs->stepping_over_breakpoint, |
| 1619 | &ecs->stepping_through_solib_after_catch, |
| 1620 | &ecs->stepping_through_solib_catchpoints, |
| 1621 | &ecs->current_line, &ecs->current_symtab); |
| 1622 | } |
| 1623 | |
| 1624 | switch_to_thread (ecs->ptid); |
| 1625 | } |
| 1626 | |
| 1627 | static void |
| 1628 | adjust_pc_after_break (struct execution_control_state *ecs) |
| 1629 | { |
| 1630 | struct regcache *regcache = get_thread_regcache (ecs->ptid); |
| 1631 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 1632 | CORE_ADDR breakpoint_pc; |
| 1633 | |
| 1634 | /* If this target does not decrement the PC after breakpoints, then |
| 1635 | we have nothing to do. */ |
| 1636 | if (gdbarch_decr_pc_after_break (gdbarch) == 0) |
| 1637 | return; |
| 1638 | |
| 1639 | /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If |
| 1640 | we aren't, just return. |
| 1641 | |
| 1642 | We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not |
| 1643 | affected by gdbarch_decr_pc_after_break. Other waitkinds which are |
| 1644 | implemented by software breakpoints should be handled through the normal |
| 1645 | breakpoint layer. |
| 1646 | |
| 1647 | NOTE drow/2004-01-31: On some targets, breakpoints may generate |
| 1648 | different signals (SIGILL or SIGEMT for instance), but it is less |
| 1649 | clear where the PC is pointing afterwards. It may not match |
| 1650 | gdbarch_decr_pc_after_break. I don't know any specific target that |
| 1651 | generates these signals at breakpoints (the code has been in GDB since at |
| 1652 | least 1992) so I can not guess how to handle them here. |
| 1653 | |
| 1654 | In earlier versions of GDB, a target with |
| 1655 | gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a |
| 1656 | watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any |
| 1657 | target with both of these set in GDB history, and it seems unlikely to be |
| 1658 | correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */ |
| 1659 | |
| 1660 | if (ecs->ws.kind != TARGET_WAITKIND_STOPPED) |
| 1661 | return; |
| 1662 | |
| 1663 | if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP) |
| 1664 | return; |
| 1665 | |
| 1666 | /* Find the location where (if we've hit a breakpoint) the |
| 1667 | breakpoint would be. */ |
| 1668 | breakpoint_pc = regcache_read_pc (regcache) |
| 1669 | - gdbarch_decr_pc_after_break (gdbarch); |
| 1670 | |
| 1671 | /* Check whether there actually is a software breakpoint inserted |
| 1672 | at that location. */ |
| 1673 | if (software_breakpoint_inserted_here_p (breakpoint_pc)) |
| 1674 | { |
| 1675 | /* When using hardware single-step, a SIGTRAP is reported for both |
| 1676 | a completed single-step and a software breakpoint. Need to |
| 1677 | differentiate between the two, as the latter needs adjusting |
| 1678 | but the former does not. |
| 1679 | |
| 1680 | The SIGTRAP can be due to a completed hardware single-step only if |
| 1681 | - we didn't insert software single-step breakpoints |
| 1682 | - the thread to be examined is still the current thread |
| 1683 | - this thread is currently being stepped |
| 1684 | |
| 1685 | If any of these events did not occur, we must have stopped due |
| 1686 | to hitting a software breakpoint, and have to back up to the |
| 1687 | breakpoint address. |
| 1688 | |
| 1689 | As a special case, we could have hardware single-stepped a |
| 1690 | software breakpoint. In this case (prev_pc == breakpoint_pc), |
| 1691 | we also need to back up to the breakpoint address. */ |
| 1692 | |
| 1693 | if (singlestep_breakpoints_inserted_p |
| 1694 | || !ptid_equal (ecs->ptid, inferior_ptid) |
| 1695 | || !currently_stepping (ecs) |
| 1696 | || prev_pc == breakpoint_pc) |
| 1697 | regcache_write_pc (regcache, breakpoint_pc); |
| 1698 | } |
| 1699 | } |
| 1700 | |
| 1701 | /* Given an execution control state that has been freshly filled in |
| 1702 | by an event from the inferior, figure out what it means and take |
| 1703 | appropriate action. */ |
| 1704 | |
| 1705 | void |
| 1706 | handle_inferior_event (struct execution_control_state *ecs) |
| 1707 | { |
| 1708 | int sw_single_step_trap_p = 0; |
| 1709 | int stopped_by_watchpoint; |
| 1710 | int stepped_after_stopped_by_watchpoint = 0; |
| 1711 | |
| 1712 | breakpoint_retire_moribund (); |
| 1713 | |
| 1714 | /* Cache the last pid/waitstatus. */ |
| 1715 | target_last_wait_ptid = ecs->ptid; |
| 1716 | target_last_waitstatus = *ecs->wp; |
| 1717 | |
| 1718 | /* Always clear state belonging to the previous time we stopped. */ |
| 1719 | stop_stack_dummy = 0; |
| 1720 | |
| 1721 | adjust_pc_after_break (ecs); |
| 1722 | |
| 1723 | switch (ecs->infwait_state) |
| 1724 | { |
| 1725 | case infwait_thread_hop_state: |
| 1726 | if (debug_infrun) |
| 1727 | fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n"); |
| 1728 | /* Cancel the waiton_ptid. */ |
| 1729 | ecs->waiton_ptid = pid_to_ptid (-1); |
| 1730 | break; |
| 1731 | |
| 1732 | case infwait_normal_state: |
| 1733 | if (debug_infrun) |
| 1734 | fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n"); |
| 1735 | break; |
| 1736 | |
| 1737 | case infwait_step_watch_state: |
| 1738 | if (debug_infrun) |
| 1739 | fprintf_unfiltered (gdb_stdlog, |
| 1740 | "infrun: infwait_step_watch_state\n"); |
| 1741 | |
| 1742 | stepped_after_stopped_by_watchpoint = 1; |
| 1743 | break; |
| 1744 | |
| 1745 | case infwait_nonstep_watch_state: |
| 1746 | if (debug_infrun) |
| 1747 | fprintf_unfiltered (gdb_stdlog, |
| 1748 | "infrun: infwait_nonstep_watch_state\n"); |
| 1749 | insert_breakpoints (); |
| 1750 | |
| 1751 | /* FIXME-maybe: is this cleaner than setting a flag? Does it |
| 1752 | handle things like signals arriving and other things happening |
| 1753 | in combination correctly? */ |
| 1754 | stepped_after_stopped_by_watchpoint = 1; |
| 1755 | break; |
| 1756 | |
| 1757 | default: |
| 1758 | internal_error (__FILE__, __LINE__, _("bad switch")); |
| 1759 | } |
| 1760 | ecs->infwait_state = infwait_normal_state; |
| 1761 | |
| 1762 | reinit_frame_cache (); |
| 1763 | |
| 1764 | /* If it's a new process, add it to the thread database */ |
| 1765 | |
| 1766 | ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid) |
| 1767 | && !ptid_equal (ecs->ptid, minus_one_ptid) |
| 1768 | && !in_thread_list (ecs->ptid)); |
| 1769 | |
| 1770 | if (ecs->ws.kind != TARGET_WAITKIND_EXITED |
| 1771 | && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event) |
| 1772 | add_thread (ecs->ptid); |
| 1773 | |
| 1774 | /* Mark all threads as not-executing. In non-stop, this should be |
| 1775 | adjusted to only mark ecs->ptid. */ |
| 1776 | if (ecs->ws.kind != TARGET_WAITKIND_IGNORE) |
| 1777 | set_executing (pid_to_ptid (-1), 0); |
| 1778 | |
| 1779 | switch (ecs->ws.kind) |
| 1780 | { |
| 1781 | case TARGET_WAITKIND_LOADED: |
| 1782 | if (debug_infrun) |
| 1783 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n"); |
| 1784 | /* Ignore gracefully during startup of the inferior, as it might |
| 1785 | be the shell which has just loaded some objects, otherwise |
| 1786 | add the symbols for the newly loaded objects. Also ignore at |
| 1787 | the beginning of an attach or remote session; we will query |
| 1788 | the full list of libraries once the connection is |
| 1789 | established. */ |
| 1790 | if (stop_soon == NO_STOP_QUIETLY) |
| 1791 | { |
| 1792 | /* Check for any newly added shared libraries if we're |
| 1793 | supposed to be adding them automatically. Switch |
| 1794 | terminal for any messages produced by |
| 1795 | breakpoint_re_set. */ |
| 1796 | target_terminal_ours_for_output (); |
| 1797 | /* NOTE: cagney/2003-11-25: Make certain that the target |
| 1798 | stack's section table is kept up-to-date. Architectures, |
| 1799 | (e.g., PPC64), use the section table to perform |
| 1800 | operations such as address => section name and hence |
| 1801 | require the table to contain all sections (including |
| 1802 | those found in shared libraries). */ |
| 1803 | /* NOTE: cagney/2003-11-25: Pass current_target and not |
| 1804 | exec_ops to SOLIB_ADD. This is because current GDB is |
| 1805 | only tooled to propagate section_table changes out from |
| 1806 | the "current_target" (see target_resize_to_sections), and |
| 1807 | not up from the exec stratum. This, of course, isn't |
| 1808 | right. "infrun.c" should only interact with the |
| 1809 | exec/process stratum, instead relying on the target stack |
| 1810 | to propagate relevant changes (stop, section table |
| 1811 | changed, ...) up to other layers. */ |
| 1812 | #ifdef SOLIB_ADD |
| 1813 | SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add); |
| 1814 | #else |
| 1815 | solib_add (NULL, 0, ¤t_target, auto_solib_add); |
| 1816 | #endif |
| 1817 | target_terminal_inferior (); |
| 1818 | |
| 1819 | /* If requested, stop when the dynamic linker notifies |
| 1820 | gdb of events. This allows the user to get control |
| 1821 | and place breakpoints in initializer routines for |
| 1822 | dynamically loaded objects (among other things). */ |
| 1823 | if (stop_on_solib_events) |
| 1824 | { |
| 1825 | stop_stepping (ecs); |
| 1826 | return; |
| 1827 | } |
| 1828 | |
| 1829 | /* NOTE drow/2007-05-11: This might be a good place to check |
| 1830 | for "catch load". */ |
| 1831 | } |
| 1832 | |
| 1833 | /* If we are skipping through a shell, or through shared library |
| 1834 | loading that we aren't interested in, resume the program. If |
| 1835 | we're running the program normally, also resume. But stop if |
| 1836 | we're attaching or setting up a remote connection. */ |
| 1837 | if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY) |
| 1838 | { |
| 1839 | /* Loading of shared libraries might have changed breakpoint |
| 1840 | addresses. Make sure new breakpoints are inserted. */ |
| 1841 | if (stop_soon == NO_STOP_QUIETLY |
| 1842 | && !breakpoints_always_inserted_mode ()) |
| 1843 | insert_breakpoints (); |
| 1844 | resume (0, TARGET_SIGNAL_0); |
| 1845 | prepare_to_wait (ecs); |
| 1846 | return; |
| 1847 | } |
| 1848 | |
| 1849 | break; |
| 1850 | |
| 1851 | case TARGET_WAITKIND_SPURIOUS: |
| 1852 | if (debug_infrun) |
| 1853 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n"); |
| 1854 | resume (0, TARGET_SIGNAL_0); |
| 1855 | prepare_to_wait (ecs); |
| 1856 | return; |
| 1857 | |
| 1858 | case TARGET_WAITKIND_EXITED: |
| 1859 | if (debug_infrun) |
| 1860 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n"); |
| 1861 | target_terminal_ours (); /* Must do this before mourn anyway */ |
| 1862 | print_stop_reason (EXITED, ecs->ws.value.integer); |
| 1863 | |
| 1864 | /* Record the exit code in the convenience variable $_exitcode, so |
| 1865 | that the user can inspect this again later. */ |
| 1866 | set_internalvar (lookup_internalvar ("_exitcode"), |
| 1867 | value_from_longest (builtin_type_int, |
| 1868 | (LONGEST) ecs->ws.value.integer)); |
| 1869 | gdb_flush (gdb_stdout); |
| 1870 | target_mourn_inferior (); |
| 1871 | singlestep_breakpoints_inserted_p = 0; |
| 1872 | stop_print_frame = 0; |
| 1873 | stop_stepping (ecs); |
| 1874 | return; |
| 1875 | |
| 1876 | case TARGET_WAITKIND_SIGNALLED: |
| 1877 | if (debug_infrun) |
| 1878 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n"); |
| 1879 | stop_print_frame = 0; |
| 1880 | stop_signal = ecs->ws.value.sig; |
| 1881 | target_terminal_ours (); /* Must do this before mourn anyway */ |
| 1882 | |
| 1883 | /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't |
| 1884 | reach here unless the inferior is dead. However, for years |
| 1885 | target_kill() was called here, which hints that fatal signals aren't |
| 1886 | really fatal on some systems. If that's true, then some changes |
| 1887 | may be needed. */ |
| 1888 | target_mourn_inferior (); |
| 1889 | |
| 1890 | print_stop_reason (SIGNAL_EXITED, stop_signal); |
| 1891 | singlestep_breakpoints_inserted_p = 0; |
| 1892 | stop_stepping (ecs); |
| 1893 | return; |
| 1894 | |
| 1895 | /* The following are the only cases in which we keep going; |
| 1896 | the above cases end in a continue or goto. */ |
| 1897 | case TARGET_WAITKIND_FORKED: |
| 1898 | case TARGET_WAITKIND_VFORKED: |
| 1899 | if (debug_infrun) |
| 1900 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n"); |
| 1901 | stop_signal = TARGET_SIGNAL_TRAP; |
| 1902 | pending_follow.kind = ecs->ws.kind; |
| 1903 | |
| 1904 | pending_follow.fork_event.parent_pid = ecs->ptid; |
| 1905 | pending_follow.fork_event.child_pid = ecs->ws.value.related_pid; |
| 1906 | |
| 1907 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 1908 | { |
| 1909 | context_switch (ecs); |
| 1910 | reinit_frame_cache (); |
| 1911 | } |
| 1912 | |
| 1913 | stop_pc = read_pc (); |
| 1914 | |
| 1915 | stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid); |
| 1916 | |
| 1917 | ecs->random_signal = !bpstat_explains_signal (stop_bpstat); |
| 1918 | |
| 1919 | /* If no catchpoint triggered for this, then keep going. */ |
| 1920 | if (ecs->random_signal) |
| 1921 | { |
| 1922 | stop_signal = TARGET_SIGNAL_0; |
| 1923 | keep_going (ecs); |
| 1924 | return; |
| 1925 | } |
| 1926 | goto process_event_stop_test; |
| 1927 | |
| 1928 | case TARGET_WAITKIND_EXECD: |
| 1929 | if (debug_infrun) |
| 1930 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n"); |
| 1931 | stop_signal = TARGET_SIGNAL_TRAP; |
| 1932 | |
| 1933 | pending_follow.execd_pathname = |
| 1934 | savestring (ecs->ws.value.execd_pathname, |
| 1935 | strlen (ecs->ws.value.execd_pathname)); |
| 1936 | |
| 1937 | /* This causes the eventpoints and symbol table to be reset. Must |
| 1938 | do this now, before trying to determine whether to stop. */ |
| 1939 | follow_exec (inferior_ptid, pending_follow.execd_pathname); |
| 1940 | xfree (pending_follow.execd_pathname); |
| 1941 | |
| 1942 | stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 1943 | ecs->saved_inferior_ptid = inferior_ptid; |
| 1944 | inferior_ptid = ecs->ptid; |
| 1945 | |
| 1946 | stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid); |
| 1947 | |
| 1948 | ecs->random_signal = !bpstat_explains_signal (stop_bpstat); |
| 1949 | inferior_ptid = ecs->saved_inferior_ptid; |
| 1950 | |
| 1951 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 1952 | { |
| 1953 | context_switch (ecs); |
| 1954 | reinit_frame_cache (); |
| 1955 | } |
| 1956 | |
| 1957 | /* If no catchpoint triggered for this, then keep going. */ |
| 1958 | if (ecs->random_signal) |
| 1959 | { |
| 1960 | stop_signal = TARGET_SIGNAL_0; |
| 1961 | keep_going (ecs); |
| 1962 | return; |
| 1963 | } |
| 1964 | goto process_event_stop_test; |
| 1965 | |
| 1966 | /* Be careful not to try to gather much state about a thread |
| 1967 | that's in a syscall. It's frequently a losing proposition. */ |
| 1968 | case TARGET_WAITKIND_SYSCALL_ENTRY: |
| 1969 | if (debug_infrun) |
| 1970 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n"); |
| 1971 | resume (0, TARGET_SIGNAL_0); |
| 1972 | prepare_to_wait (ecs); |
| 1973 | return; |
| 1974 | |
| 1975 | /* Before examining the threads further, step this thread to |
| 1976 | get it entirely out of the syscall. (We get notice of the |
| 1977 | event when the thread is just on the verge of exiting a |
| 1978 | syscall. Stepping one instruction seems to get it back |
| 1979 | into user code.) */ |
| 1980 | case TARGET_WAITKIND_SYSCALL_RETURN: |
| 1981 | if (debug_infrun) |
| 1982 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n"); |
| 1983 | target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); |
| 1984 | prepare_to_wait (ecs); |
| 1985 | return; |
| 1986 | |
| 1987 | case TARGET_WAITKIND_STOPPED: |
| 1988 | if (debug_infrun) |
| 1989 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n"); |
| 1990 | stop_signal = ecs->ws.value.sig; |
| 1991 | break; |
| 1992 | |
| 1993 | /* We had an event in the inferior, but we are not interested |
| 1994 | in handling it at this level. The lower layers have already |
| 1995 | done what needs to be done, if anything. |
| 1996 | |
| 1997 | One of the possible circumstances for this is when the |
| 1998 | inferior produces output for the console. The inferior has |
| 1999 | not stopped, and we are ignoring the event. Another possible |
| 2000 | circumstance is any event which the lower level knows will be |
| 2001 | reported multiple times without an intervening resume. */ |
| 2002 | case TARGET_WAITKIND_IGNORE: |
| 2003 | if (debug_infrun) |
| 2004 | fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n"); |
| 2005 | prepare_to_wait (ecs); |
| 2006 | return; |
| 2007 | } |
| 2008 | |
| 2009 | /* We may want to consider not doing a resume here in order to give |
| 2010 | the user a chance to play with the new thread. It might be good |
| 2011 | to make that a user-settable option. */ |
| 2012 | |
| 2013 | /* At this point, all threads are stopped (happens automatically in |
| 2014 | either the OS or the native code). Therefore we need to continue |
| 2015 | all threads in order to make progress. */ |
| 2016 | if (ecs->new_thread_event) |
| 2017 | { |
| 2018 | target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0); |
| 2019 | prepare_to_wait (ecs); |
| 2020 | return; |
| 2021 | } |
| 2022 | |
| 2023 | /* Do we need to clean up the state of a thread that has completed a |
| 2024 | displaced single-step? (Doing so usually affects the PC, so do |
| 2025 | it here, before we set stop_pc.) */ |
| 2026 | displaced_step_fixup (ecs->ptid, stop_signal); |
| 2027 | |
| 2028 | stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid)); |
| 2029 | |
| 2030 | if (debug_infrun) |
| 2031 | { |
| 2032 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n", |
| 2033 | paddr_nz (stop_pc)); |
| 2034 | if (STOPPED_BY_WATCHPOINT (&ecs->ws)) |
| 2035 | { |
| 2036 | CORE_ADDR addr; |
| 2037 | fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n"); |
| 2038 | |
| 2039 | if (target_stopped_data_address (¤t_target, &addr)) |
| 2040 | fprintf_unfiltered (gdb_stdlog, |
| 2041 | "infrun: stopped data address = 0x%s\n", |
| 2042 | paddr_nz (addr)); |
| 2043 | else |
| 2044 | fprintf_unfiltered (gdb_stdlog, |
| 2045 | "infrun: (no data address available)\n"); |
| 2046 | } |
| 2047 | } |
| 2048 | |
| 2049 | if (stepping_past_singlestep_breakpoint) |
| 2050 | { |
| 2051 | gdb_assert (singlestep_breakpoints_inserted_p); |
| 2052 | gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid)); |
| 2053 | gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid)); |
| 2054 | |
| 2055 | stepping_past_singlestep_breakpoint = 0; |
| 2056 | |
| 2057 | /* We've either finished single-stepping past the single-step |
| 2058 | breakpoint, or stopped for some other reason. It would be nice if |
| 2059 | we could tell, but we can't reliably. */ |
| 2060 | if (stop_signal == TARGET_SIGNAL_TRAP) |
| 2061 | { |
| 2062 | if (debug_infrun) |
| 2063 | fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n"); |
| 2064 | /* Pull the single step breakpoints out of the target. */ |
| 2065 | remove_single_step_breakpoints (); |
| 2066 | singlestep_breakpoints_inserted_p = 0; |
| 2067 | |
| 2068 | ecs->random_signal = 0; |
| 2069 | |
| 2070 | ecs->ptid = saved_singlestep_ptid; |
| 2071 | context_switch (ecs); |
| 2072 | if (deprecated_context_hook) |
| 2073 | deprecated_context_hook (pid_to_thread_id (ecs->ptid)); |
| 2074 | |
| 2075 | resume (1, TARGET_SIGNAL_0); |
| 2076 | prepare_to_wait (ecs); |
| 2077 | return; |
| 2078 | } |
| 2079 | } |
| 2080 | |
| 2081 | stepping_past_singlestep_breakpoint = 0; |
| 2082 | |
| 2083 | if (!ptid_equal (deferred_step_ptid, null_ptid)) |
| 2084 | { |
| 2085 | /* If we stopped for some other reason than single-stepping, ignore |
| 2086 | the fact that we were supposed to switch back. */ |
| 2087 | if (stop_signal == TARGET_SIGNAL_TRAP) |
| 2088 | { |
| 2089 | if (debug_infrun) |
| 2090 | fprintf_unfiltered (gdb_stdlog, |
| 2091 | "infrun: handling deferred step\n"); |
| 2092 | |
| 2093 | /* Pull the single step breakpoints out of the target. */ |
| 2094 | if (singlestep_breakpoints_inserted_p) |
| 2095 | { |
| 2096 | remove_single_step_breakpoints (); |
| 2097 | singlestep_breakpoints_inserted_p = 0; |
| 2098 | } |
| 2099 | |
| 2100 | /* Note: We do not call context_switch at this point, as the |
| 2101 | context is already set up for stepping the original thread. */ |
| 2102 | switch_to_thread (deferred_step_ptid); |
| 2103 | deferred_step_ptid = null_ptid; |
| 2104 | /* Suppress spurious "Switching to ..." message. */ |
| 2105 | previous_inferior_ptid = inferior_ptid; |
| 2106 | |
| 2107 | resume (1, TARGET_SIGNAL_0); |
| 2108 | prepare_to_wait (ecs); |
| 2109 | return; |
| 2110 | } |
| 2111 | |
| 2112 | deferred_step_ptid = null_ptid; |
| 2113 | } |
| 2114 | |
| 2115 | /* See if a thread hit a thread-specific breakpoint that was meant for |
| 2116 | another thread. If so, then step that thread past the breakpoint, |
| 2117 | and continue it. */ |
| 2118 | |
| 2119 | if (stop_signal == TARGET_SIGNAL_TRAP) |
| 2120 | { |
| 2121 | int thread_hop_needed = 0; |
| 2122 | |
| 2123 | /* Check if a regular breakpoint has been hit before checking |
| 2124 | for a potential single step breakpoint. Otherwise, GDB will |
| 2125 | not see this breakpoint hit when stepping onto breakpoints. */ |
| 2126 | if (regular_breakpoint_inserted_here_p (stop_pc)) |
| 2127 | { |
| 2128 | ecs->random_signal = 0; |
| 2129 | if (!breakpoint_thread_match (stop_pc, ecs->ptid)) |
| 2130 | thread_hop_needed = 1; |
| 2131 | } |
| 2132 | else if (singlestep_breakpoints_inserted_p) |
| 2133 | { |
| 2134 | /* We have not context switched yet, so this should be true |
| 2135 | no matter which thread hit the singlestep breakpoint. */ |
| 2136 | gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid)); |
| 2137 | if (debug_infrun) |
| 2138 | fprintf_unfiltered (gdb_stdlog, "infrun: software single step " |
| 2139 | "trap for %s\n", |
| 2140 | target_pid_to_str (ecs->ptid)); |
| 2141 | |
| 2142 | ecs->random_signal = 0; |
| 2143 | /* The call to in_thread_list is necessary because PTIDs sometimes |
| 2144 | change when we go from single-threaded to multi-threaded. If |
| 2145 | the singlestep_ptid is still in the list, assume that it is |
| 2146 | really different from ecs->ptid. */ |
| 2147 | if (!ptid_equal (singlestep_ptid, ecs->ptid) |
| 2148 | && in_thread_list (singlestep_ptid)) |
| 2149 | { |
| 2150 | /* If the PC of the thread we were trying to single-step |
| 2151 | has changed, discard this event (which we were going |
| 2152 | to ignore anyway), and pretend we saw that thread |
| 2153 | trap. This prevents us continuously moving the |
| 2154 | single-step breakpoint forward, one instruction at a |
| 2155 | time. If the PC has changed, then the thread we were |
| 2156 | trying to single-step has trapped or been signalled, |
| 2157 | but the event has not been reported to GDB yet. |
| 2158 | |
| 2159 | There might be some cases where this loses signal |
| 2160 | information, if a signal has arrived at exactly the |
| 2161 | same time that the PC changed, but this is the best |
| 2162 | we can do with the information available. Perhaps we |
| 2163 | should arrange to report all events for all threads |
| 2164 | when they stop, or to re-poll the remote looking for |
| 2165 | this particular thread (i.e. temporarily enable |
| 2166 | schedlock). */ |
| 2167 | |
| 2168 | CORE_ADDR new_singlestep_pc |
| 2169 | = regcache_read_pc (get_thread_regcache (singlestep_ptid)); |
| 2170 | |
| 2171 | if (new_singlestep_pc != singlestep_pc) |
| 2172 | { |
| 2173 | if (debug_infrun) |
| 2174 | fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread," |
| 2175 | " but expected thread advanced also\n"); |
| 2176 | |
| 2177 | /* The current context still belongs to |
| 2178 | singlestep_ptid. Don't swap here, since that's |
| 2179 | the context we want to use. Just fudge our |
| 2180 | state and continue. */ |
| 2181 | ecs->ptid = singlestep_ptid; |
| 2182 | stop_pc = new_singlestep_pc; |
| 2183 | } |
| 2184 | else |
| 2185 | { |
| 2186 | if (debug_infrun) |
| 2187 | fprintf_unfiltered (gdb_stdlog, |
| 2188 | "infrun: unexpected thread\n"); |
| 2189 | |
| 2190 | thread_hop_needed = 1; |
| 2191 | stepping_past_singlestep_breakpoint = 1; |
| 2192 | saved_singlestep_ptid = singlestep_ptid; |
| 2193 | } |
| 2194 | } |
| 2195 | } |
| 2196 | |
| 2197 | if (thread_hop_needed) |
| 2198 | { |
| 2199 | int remove_status = 0; |
| 2200 | |
| 2201 | if (debug_infrun) |
| 2202 | fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n"); |
| 2203 | |
| 2204 | /* Saw a breakpoint, but it was hit by the wrong thread. |
| 2205 | Just continue. */ |
| 2206 | |
| 2207 | if (singlestep_breakpoints_inserted_p) |
| 2208 | { |
| 2209 | /* Pull the single step breakpoints out of the target. */ |
| 2210 | remove_single_step_breakpoints (); |
| 2211 | singlestep_breakpoints_inserted_p = 0; |
| 2212 | } |
| 2213 | |
| 2214 | /* If the arch can displace step, don't remove the |
| 2215 | breakpoints. */ |
| 2216 | if (!use_displaced_stepping (current_gdbarch)) |
| 2217 | remove_status = remove_breakpoints (); |
| 2218 | |
| 2219 | /* Did we fail to remove breakpoints? If so, try |
| 2220 | to set the PC past the bp. (There's at least |
| 2221 | one situation in which we can fail to remove |
| 2222 | the bp's: On HP-UX's that use ttrace, we can't |
| 2223 | change the address space of a vforking child |
| 2224 | process until the child exits (well, okay, not |
| 2225 | then either :-) or execs. */ |
| 2226 | if (remove_status != 0) |
| 2227 | error (_("Cannot step over breakpoint hit in wrong thread")); |
| 2228 | else |
| 2229 | { /* Single step */ |
| 2230 | if (!ptid_equal (inferior_ptid, ecs->ptid)) |
| 2231 | context_switch (ecs); |
| 2232 | ecs->waiton_ptid = ecs->ptid; |
| 2233 | ecs->wp = &(ecs->ws); |
| 2234 | ecs->stepping_over_breakpoint = 1; |
| 2235 | |
| 2236 | ecs->infwait_state = infwait_thread_hop_state; |
| 2237 | keep_going (ecs); |
| 2238 | registers_changed (); |
| 2239 | return; |
| 2240 | } |
| 2241 | } |
| 2242 | else if (singlestep_breakpoints_inserted_p) |
| 2243 | { |
| 2244 | sw_single_step_trap_p = 1; |
| 2245 | ecs->random_signal = 0; |
| 2246 | } |
| 2247 | } |
| 2248 | else |
| 2249 | ecs->random_signal = 1; |
| 2250 | |
| 2251 | /* See if something interesting happened to the non-current thread. If |
| 2252 | so, then switch to that thread. */ |
| 2253 | if (!ptid_equal (ecs->ptid, inferior_ptid)) |
| 2254 | { |
| 2255 | if (debug_infrun) |
| 2256 | fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n"); |
| 2257 | |
| 2258 | context_switch (ecs); |
| 2259 | |
| 2260 | if (deprecated_context_hook) |
| 2261 | deprecated_context_hook (pid_to_thread_id (ecs->ptid)); |
| 2262 | } |
| 2263 | |
| 2264 | if (singlestep_breakpoints_inserted_p) |
| 2265 | { |
| 2266 | /* Pull the single step breakpoints out of the target. */ |
| 2267 | remove_single_step_breakpoints (); |
| 2268 | singlestep_breakpoints_inserted_p = 0; |
| 2269 | } |
| 2270 | |
| 2271 | if (stepped_after_stopped_by_watchpoint) |
| 2272 | stopped_by_watchpoint = 0; |
| 2273 | else |
| 2274 | stopped_by_watchpoint = watchpoints_triggered (&ecs->ws); |
| 2275 | |
| 2276 | /* If necessary, step over this watchpoint. We'll be back to display |
| 2277 | it in a moment. */ |
| 2278 | if (stopped_by_watchpoint |
| 2279 | && (HAVE_STEPPABLE_WATCHPOINT |
| 2280 | || gdbarch_have_nonsteppable_watchpoint (current_gdbarch))) |
| 2281 | { |
| 2282 | /* At this point, we are stopped at an instruction which has |
| 2283 | attempted to write to a piece of memory under control of |
| 2284 | a watchpoint. The instruction hasn't actually executed |
| 2285 | yet. If we were to evaluate the watchpoint expression |
| 2286 | now, we would get the old value, and therefore no change |
| 2287 | would seem to have occurred. |
| 2288 | |
| 2289 | In order to make watchpoints work `right', we really need |
| 2290 | to complete the memory write, and then evaluate the |
| 2291 | watchpoint expression. We do this by single-stepping the |
| 2292 | target. |
| 2293 | |
| 2294 | It may not be necessary to disable the watchpoint to stop over |
| 2295 | it. For example, the PA can (with some kernel cooperation) |
| 2296 | single step over a watchpoint without disabling the watchpoint. |
| 2297 | |
| 2298 | It is far more common to need to disable a watchpoint to step |
| 2299 | the inferior over it. If we have non-steppable watchpoints, |
| 2300 | we must disable the current watchpoint; it's simplest to |
| 2301 | disable all watchpoints and breakpoints. */ |
| 2302 | |
| 2303 | if (!HAVE_STEPPABLE_WATCHPOINT) |
| 2304 | remove_breakpoints (); |
| 2305 | registers_changed (); |
| 2306 | target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */ |
| 2307 | ecs->waiton_ptid = ecs->ptid; |
| 2308 | if (HAVE_STEPPABLE_WATCHPOINT) |
| 2309 | ecs->infwait_state = infwait_step_watch_state; |
| 2310 | else |
| 2311 | ecs->infwait_state = infwait_nonstep_watch_state; |
| 2312 | prepare_to_wait (ecs); |
| 2313 | return; |
| 2314 | } |
| 2315 | |
| 2316 | ecs->stop_func_start = 0; |
| 2317 | ecs->stop_func_end = 0; |
| 2318 | ecs->stop_func_name = 0; |
| 2319 | /* Don't care about return value; stop_func_start and stop_func_name |
| 2320 | will both be 0 if it doesn't work. */ |
| 2321 | find_pc_partial_function (stop_pc, &ecs->stop_func_name, |
| 2322 | &ecs->stop_func_start, &ecs->stop_func_end); |
| 2323 | ecs->stop_func_start |
| 2324 | += gdbarch_deprecated_function_start_offset (current_gdbarch); |
| 2325 | ecs->stepping_over_breakpoint = 0; |
| 2326 | bpstat_clear (&stop_bpstat); |
| 2327 | stop_step = 0; |
| 2328 | stop_print_frame = 1; |
| 2329 | ecs->random_signal = 0; |
| 2330 | stopped_by_random_signal = 0; |
| 2331 | |
| 2332 | if (stop_signal == TARGET_SIGNAL_TRAP |
| 2333 | && stepping_over_breakpoint |
| 2334 | && gdbarch_single_step_through_delay_p (current_gdbarch) |
| 2335 | && currently_stepping (ecs)) |
| 2336 | { |
| 2337 | /* We're trying to step off a breakpoint. Turns out that we're |
| 2338 | also on an instruction that needs to be stepped multiple |
| 2339 | times before it's been fully executing. E.g., architectures |
| 2340 | with a delay slot. It needs to be stepped twice, once for |
| 2341 | the instruction and once for the delay slot. */ |
| 2342 | int step_through_delay |
| 2343 | = gdbarch_single_step_through_delay (current_gdbarch, |
| 2344 | get_current_frame ()); |
| 2345 | if (debug_infrun && step_through_delay) |
| 2346 | fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n"); |
| 2347 | if (step_range_end == 0 && step_through_delay) |
| 2348 | { |
| 2349 | /* The user issued a continue when stopped at a breakpoint. |
| 2350 | Set up for another trap and get out of here. */ |
| 2351 | ecs->stepping_over_breakpoint = 1; |
| 2352 | keep_going (ecs); |
| 2353 | return; |
| 2354 | } |
| 2355 | else if (step_through_delay) |
| 2356 | { |
| 2357 | /* The user issued a step when stopped at a breakpoint. |
| 2358 | Maybe we should stop, maybe we should not - the delay |
| 2359 | slot *might* correspond to a line of source. In any |
| 2360 | case, don't decide that here, just set |
| 2361 | ecs->stepping_over_breakpoint, making sure we |
| 2362 | single-step again before breakpoints are re-inserted. */ |
| 2363 | ecs->stepping_over_breakpoint = 1; |
| 2364 | } |
| 2365 | } |
| 2366 | |
| 2367 | /* Look at the cause of the stop, and decide what to do. |
| 2368 | The alternatives are: |
| 2369 | 1) break; to really stop and return to the debugger, |
| 2370 | 2) drop through to start up again |
| 2371 | (set ecs->stepping_over_breakpoint to 1 to single step once) |
| 2372 | 3) set ecs->random_signal to 1, and the decision between 1 and 2 |
| 2373 | will be made according to the signal handling tables. */ |
| 2374 | |
| 2375 | /* First, distinguish signals caused by the debugger from signals |
| 2376 | that have to do with the program's own actions. Note that |
| 2377 | breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending |
| 2378 | on the operating system version. Here we detect when a SIGILL or |
| 2379 | SIGEMT is really a breakpoint and change it to SIGTRAP. We do |
| 2380 | something similar for SIGSEGV, since a SIGSEGV will be generated |
| 2381 | when we're trying to execute a breakpoint instruction on a |
| 2382 | non-executable stack. This happens for call dummy breakpoints |
| 2383 | for architectures like SPARC that place call dummies on the |
| 2384 | stack. |
| 2385 | |
| 2386 | If we're doing a displaced step past a breakpoint, then the |
| 2387 | breakpoint is always inserted at the original instruction; |
| 2388 | non-standard signals can't be explained by the breakpoint. */ |
| 2389 | if (stop_signal == TARGET_SIGNAL_TRAP |
| 2390 | || (! stepping_over_breakpoint |
| 2391 | && breakpoint_inserted_here_p (stop_pc) |
| 2392 | && (stop_signal == TARGET_SIGNAL_ILL |
| 2393 | || stop_signal == TARGET_SIGNAL_SEGV |
| 2394 | || stop_signal == TARGET_SIGNAL_EMT)) |
| 2395 | || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 2396 | || stop_soon == STOP_QUIETLY_REMOTE) |
| 2397 | { |
| 2398 | if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap) |
| 2399 | { |
| 2400 | if (debug_infrun) |
| 2401 | fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n"); |
| 2402 | stop_print_frame = 0; |
| 2403 | stop_stepping (ecs); |
| 2404 | return; |
| 2405 | } |
| 2406 | |
| 2407 | /* This is originated from start_remote(), start_inferior() and |
| 2408 | shared libraries hook functions. */ |
| 2409 | if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE) |
| 2410 | { |
| 2411 | if (debug_infrun) |
| 2412 | fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n"); |
| 2413 | stop_stepping (ecs); |
| 2414 | return; |
| 2415 | } |
| 2416 | |
| 2417 | /* This originates from attach_command(). We need to overwrite |
| 2418 | the stop_signal here, because some kernels don't ignore a |
| 2419 | SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call. |
| 2420 | See more comments in inferior.h. On the other hand, if we |
| 2421 | get a non-SIGSTOP, report it to the user - assume the backend |
| 2422 | will handle the SIGSTOP if it should show up later. */ |
| 2423 | if (stop_soon == STOP_QUIETLY_NO_SIGSTOP |
| 2424 | && stop_signal == TARGET_SIGNAL_STOP) |
| 2425 | { |
| 2426 | stop_stepping (ecs); |
| 2427 | stop_signal = TARGET_SIGNAL_0; |
| 2428 | return; |
| 2429 | } |
| 2430 | |
| 2431 | /* See if there is a breakpoint at the current PC. */ |
| 2432 | stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid); |
| 2433 | |
| 2434 | /* Following in case break condition called a |
| 2435 | function. */ |
| 2436 | stop_print_frame = 1; |
| 2437 | |
| 2438 | /* NOTE: cagney/2003-03-29: These two checks for a random signal |
| 2439 | at one stage in the past included checks for an inferior |
| 2440 | function call's call dummy's return breakpoint. The original |
| 2441 | comment, that went with the test, read: |
| 2442 | |
| 2443 | ``End of a stack dummy. Some systems (e.g. Sony news) give |
| 2444 | another signal besides SIGTRAP, so check here as well as |
| 2445 | above.'' |
| 2446 | |
| 2447 | If someone ever tries to get get call dummys on a |
| 2448 | non-executable stack to work (where the target would stop |
| 2449 | with something like a SIGSEGV), then those tests might need |
| 2450 | to be re-instated. Given, however, that the tests were only |
| 2451 | enabled when momentary breakpoints were not being used, I |
| 2452 | suspect that it won't be the case. |
| 2453 | |
| 2454 | NOTE: kettenis/2004-02-05: Indeed such checks don't seem to |
| 2455 | be necessary for call dummies on a non-executable stack on |
| 2456 | SPARC. */ |
| 2457 | |
| 2458 | if (stop_signal == TARGET_SIGNAL_TRAP) |
| 2459 | ecs->random_signal |
| 2460 | = !(bpstat_explains_signal (stop_bpstat) |
| 2461 | || stepping_over_breakpoint |
| 2462 | || (step_range_end && step_resume_breakpoint == NULL)); |
| 2463 | else |
| 2464 | { |
| 2465 | ecs->random_signal = !bpstat_explains_signal (stop_bpstat); |
| 2466 | if (!ecs->random_signal) |
| 2467 | stop_signal = TARGET_SIGNAL_TRAP; |
| 2468 | } |
| 2469 | } |
| 2470 | |
| 2471 | /* When we reach this point, we've pretty much decided |
| 2472 | that the reason for stopping must've been a random |
| 2473 | (unexpected) signal. */ |
| 2474 | |
| 2475 | else |
| 2476 | ecs->random_signal = 1; |
| 2477 | |
| 2478 | process_event_stop_test: |
| 2479 | /* For the program's own signals, act according to |
| 2480 | the signal handling tables. */ |
| 2481 | |
| 2482 | if (ecs->random_signal) |
| 2483 | { |
| 2484 | /* Signal not for debugging purposes. */ |
| 2485 | int printed = 0; |
| 2486 | |
| 2487 | if (debug_infrun) |
| 2488 | fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n", stop_signal); |
| 2489 | |
| 2490 | stopped_by_random_signal = 1; |
| 2491 | |
| 2492 | if (signal_print[stop_signal]) |
| 2493 | { |
| 2494 | printed = 1; |
| 2495 | target_terminal_ours_for_output (); |
| 2496 | print_stop_reason (SIGNAL_RECEIVED, stop_signal); |
| 2497 | } |
| 2498 | if (signal_stop_state (stop_signal)) |
| 2499 | { |
| 2500 | stop_stepping (ecs); |
| 2501 | return; |
| 2502 | } |
| 2503 | /* If not going to stop, give terminal back |
| 2504 | if we took it away. */ |
| 2505 | else if (printed) |
| 2506 | target_terminal_inferior (); |
| 2507 | |
| 2508 | /* Clear the signal if it should not be passed. */ |
| 2509 | if (signal_program[stop_signal] == 0) |
| 2510 | stop_signal = TARGET_SIGNAL_0; |
| 2511 | |
| 2512 | if (prev_pc == read_pc () |
| 2513 | && stepping_over_breakpoint |
| 2514 | && step_resume_breakpoint == NULL) |
| 2515 | { |
| 2516 | /* We were just starting a new sequence, attempting to |
| 2517 | single-step off of a breakpoint and expecting a SIGTRAP. |
| 2518 | Instead this signal arrives. This signal will take us out |
| 2519 | of the stepping range so GDB needs to remember to, when |
| 2520 | the signal handler returns, resume stepping off that |
| 2521 | breakpoint. */ |
| 2522 | /* To simplify things, "continue" is forced to use the same |
| 2523 | code paths as single-step - set a breakpoint at the |
| 2524 | signal return address and then, once hit, step off that |
| 2525 | breakpoint. */ |
| 2526 | if (debug_infrun) |
| 2527 | fprintf_unfiltered (gdb_stdlog, |
| 2528 | "infrun: signal arrived while stepping over " |
| 2529 | "breakpoint\n"); |
| 2530 | |
| 2531 | insert_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2532 | ecs->step_after_step_resume_breakpoint = 1; |
| 2533 | keep_going (ecs); |
| 2534 | return; |
| 2535 | } |
| 2536 | |
| 2537 | if (step_range_end != 0 |
| 2538 | && stop_signal != TARGET_SIGNAL_0 |
| 2539 | && stop_pc >= step_range_start && stop_pc < step_range_end |
| 2540 | && frame_id_eq (get_frame_id (get_current_frame ()), |
| 2541 | step_frame_id) |
| 2542 | && step_resume_breakpoint == NULL) |
| 2543 | { |
| 2544 | /* The inferior is about to take a signal that will take it |
| 2545 | out of the single step range. Set a breakpoint at the |
| 2546 | current PC (which is presumably where the signal handler |
| 2547 | will eventually return) and then allow the inferior to |
| 2548 | run free. |
| 2549 | |
| 2550 | Note that this is only needed for a signal delivered |
| 2551 | while in the single-step range. Nested signals aren't a |
| 2552 | problem as they eventually all return. */ |
| 2553 | if (debug_infrun) |
| 2554 | fprintf_unfiltered (gdb_stdlog, |
| 2555 | "infrun: signal may take us out of " |
| 2556 | "single-step range\n"); |
| 2557 | |
| 2558 | insert_step_resume_breakpoint_at_frame (get_current_frame ()); |
| 2559 | keep_going (ecs); |
| 2560 | return; |
| 2561 | } |
| 2562 | |
| 2563 | /* Note: step_resume_breakpoint may be non-NULL. This occures |
| 2564 | when either there's a nested signal, or when there's a |
| 2565 | pending signal enabled just as the signal handler returns |
| 2566 | (leaving the inferior at the step-resume-breakpoint without |
| 2567 | actually executing it). Either way continue until the |
| 2568 | breakpoint is really hit. */ |
| 2569 | keep_going (ecs); |
| 2570 | return; |
| 2571 | } |
| 2572 | |
| 2573 | /* Handle cases caused by hitting a breakpoint. */ |
| 2574 | { |
| 2575 | CORE_ADDR jmp_buf_pc; |
| 2576 | struct bpstat_what what; |
| 2577 | |
| 2578 | what = bpstat_what (stop_bpstat); |
| 2579 | |
| 2580 | if (what.call_dummy) |
| 2581 | { |
| 2582 | stop_stack_dummy = 1; |
| 2583 | } |
| 2584 | |
| 2585 | switch (what.main_action) |
| 2586 | { |
| 2587 | case BPSTAT_WHAT_SET_LONGJMP_RESUME: |
| 2588 | /* If we hit the breakpoint at longjmp while stepping, we |
| 2589 | install a momentary breakpoint at the target of the |
| 2590 | jmp_buf. */ |
| 2591 | |
| 2592 | if (debug_infrun) |
| 2593 | fprintf_unfiltered (gdb_stdlog, |
| 2594 | "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n"); |
| 2595 | |
| 2596 | ecs->stepping_over_breakpoint = 1; |
| 2597 | |
| 2598 | if (!gdbarch_get_longjmp_target_p (current_gdbarch) |
| 2599 | || !gdbarch_get_longjmp_target (current_gdbarch, |
| 2600 | get_current_frame (), &jmp_buf_pc)) |
| 2601 | { |
| 2602 | if (debug_infrun) |
| 2603 | fprintf_unfiltered (gdb_stdlog, "\ |
| 2604 | infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n"); |
| 2605 | keep_going (ecs); |
| 2606 | return; |
| 2607 | } |
| 2608 | |
| 2609 | /* We're going to replace the current step-resume breakpoint |
| 2610 | with a longjmp-resume breakpoint. */ |
| 2611 | if (step_resume_breakpoint != NULL) |
| 2612 | delete_step_resume_breakpoint (&step_resume_breakpoint); |
| 2613 | |
| 2614 | /* Insert a breakpoint at resume address. */ |
| 2615 | insert_longjmp_resume_breakpoint (jmp_buf_pc); |
| 2616 | |
| 2617 | keep_going (ecs); |
| 2618 | return; |
| 2619 | |
| 2620 | case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME: |
| 2621 | if (debug_infrun) |
| 2622 | fprintf_unfiltered (gdb_stdlog, |
| 2623 | "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n"); |
| 2624 | |
| 2625 | gdb_assert (step_resume_breakpoint != NULL); |
| 2626 | delete_step_resume_breakpoint (&step_resume_breakpoint); |
| 2627 | |
| 2628 | stop_step = 1; |
| 2629 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 2630 | stop_stepping (ecs); |
| 2631 | return; |
| 2632 | |
| 2633 | case BPSTAT_WHAT_SINGLE: |
| 2634 | if (debug_infrun) |
| 2635 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n"); |
| 2636 | ecs->stepping_over_breakpoint = 1; |
| 2637 | /* Still need to check other stuff, at least the case |
| 2638 | where we are stepping and step out of the right range. */ |
| 2639 | break; |
| 2640 | |
| 2641 | case BPSTAT_WHAT_STOP_NOISY: |
| 2642 | if (debug_infrun) |
| 2643 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n"); |
| 2644 | stop_print_frame = 1; |
| 2645 | |
| 2646 | /* We are about to nuke the step_resume_breakpointt via the |
| 2647 | cleanup chain, so no need to worry about it here. */ |
| 2648 | |
| 2649 | stop_stepping (ecs); |
| 2650 | return; |
| 2651 | |
| 2652 | case BPSTAT_WHAT_STOP_SILENT: |
| 2653 | if (debug_infrun) |
| 2654 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n"); |
| 2655 | stop_print_frame = 0; |
| 2656 | |
| 2657 | /* We are about to nuke the step_resume_breakpoin via the |
| 2658 | cleanup chain, so no need to worry about it here. */ |
| 2659 | |
| 2660 | stop_stepping (ecs); |
| 2661 | return; |
| 2662 | |
| 2663 | case BPSTAT_WHAT_STEP_RESUME: |
| 2664 | /* This proably demands a more elegant solution, but, yeah |
| 2665 | right... |
| 2666 | |
| 2667 | This function's use of the simple variable |
| 2668 | step_resume_breakpoint doesn't seem to accomodate |
| 2669 | simultaneously active step-resume bp's, although the |
| 2670 | breakpoint list certainly can. |
| 2671 | |
| 2672 | If we reach here and step_resume_breakpoint is already |
| 2673 | NULL, then apparently we have multiple active |
| 2674 | step-resume bp's. We'll just delete the breakpoint we |
| 2675 | stopped at, and carry on. |
| 2676 | |
| 2677 | Correction: what the code currently does is delete a |
| 2678 | step-resume bp, but it makes no effort to ensure that |
| 2679 | the one deleted is the one currently stopped at. MVS */ |
| 2680 | |
| 2681 | if (debug_infrun) |
| 2682 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n"); |
| 2683 | |
| 2684 | if (step_resume_breakpoint == NULL) |
| 2685 | { |
| 2686 | step_resume_breakpoint = |
| 2687 | bpstat_find_step_resume_breakpoint (stop_bpstat); |
| 2688 | } |
| 2689 | delete_step_resume_breakpoint (&step_resume_breakpoint); |
| 2690 | if (ecs->step_after_step_resume_breakpoint) |
| 2691 | { |
| 2692 | /* Back when the step-resume breakpoint was inserted, we |
| 2693 | were trying to single-step off a breakpoint. Go back |
| 2694 | to doing that. */ |
| 2695 | ecs->step_after_step_resume_breakpoint = 0; |
| 2696 | ecs->stepping_over_breakpoint = 1; |
| 2697 | keep_going (ecs); |
| 2698 | return; |
| 2699 | } |
| 2700 | break; |
| 2701 | |
| 2702 | case BPSTAT_WHAT_CHECK_SHLIBS: |
| 2703 | case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK: |
| 2704 | { |
| 2705 | if (debug_infrun) |
| 2706 | fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n"); |
| 2707 | |
| 2708 | /* Check for any newly added shared libraries if we're |
| 2709 | supposed to be adding them automatically. Switch |
| 2710 | terminal for any messages produced by |
| 2711 | breakpoint_re_set. */ |
| 2712 | target_terminal_ours_for_output (); |
| 2713 | /* NOTE: cagney/2003-11-25: Make certain that the target |
| 2714 | stack's section table is kept up-to-date. Architectures, |
| 2715 | (e.g., PPC64), use the section table to perform |
| 2716 | operations such as address => section name and hence |
| 2717 | require the table to contain all sections (including |
| 2718 | those found in shared libraries). */ |
| 2719 | /* NOTE: cagney/2003-11-25: Pass current_target and not |
| 2720 | exec_ops to SOLIB_ADD. This is because current GDB is |
| 2721 | only tooled to propagate section_table changes out from |
| 2722 | the "current_target" (see target_resize_to_sections), and |
| 2723 | not up from the exec stratum. This, of course, isn't |
| 2724 | right. "infrun.c" should only interact with the |
| 2725 | exec/process stratum, instead relying on the target stack |
| 2726 | to propagate relevant changes (stop, section table |
| 2727 | changed, ...) up to other layers. */ |
| 2728 | #ifdef SOLIB_ADD |
| 2729 | SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add); |
| 2730 | #else |
| 2731 | solib_add (NULL, 0, ¤t_target, auto_solib_add); |
| 2732 | #endif |
| 2733 | target_terminal_inferior (); |
| 2734 | |
| 2735 | /* If requested, stop when the dynamic linker notifies |
| 2736 | gdb of events. This allows the user to get control |
| 2737 | and place breakpoints in initializer routines for |
| 2738 | dynamically loaded objects (among other things). */ |
| 2739 | if (stop_on_solib_events || stop_stack_dummy) |
| 2740 | { |
| 2741 | stop_stepping (ecs); |
| 2742 | return; |
| 2743 | } |
| 2744 | |
| 2745 | /* If we stopped due to an explicit catchpoint, then the |
| 2746 | (see above) call to SOLIB_ADD pulled in any symbols |
| 2747 | from a newly-loaded library, if appropriate. |
| 2748 | |
| 2749 | We do want the inferior to stop, but not where it is |
| 2750 | now, which is in the dynamic linker callback. Rather, |
| 2751 | we would like it stop in the user's program, just after |
| 2752 | the call that caused this catchpoint to trigger. That |
| 2753 | gives the user a more useful vantage from which to |
| 2754 | examine their program's state. */ |
| 2755 | else if (what.main_action |
| 2756 | == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK) |
| 2757 | { |
| 2758 | /* ??rehrauer: If I could figure out how to get the |
| 2759 | right return PC from here, we could just set a temp |
| 2760 | breakpoint and resume. I'm not sure we can without |
| 2761 | cracking open the dld's shared libraries and sniffing |
| 2762 | their unwind tables and text/data ranges, and that's |
| 2763 | not a terribly portable notion. |
| 2764 | |
| 2765 | Until that time, we must step the inferior out of the |
| 2766 | dld callback, and also out of the dld itself (and any |
| 2767 | code or stubs in libdld.sl, such as "shl_load" and |
| 2768 | friends) until we reach non-dld code. At that point, |
| 2769 | we can stop stepping. */ |
| 2770 | bpstat_get_triggered_catchpoints (stop_bpstat, |
| 2771 | &ecs-> |
| 2772 | stepping_through_solib_catchpoints); |
| 2773 | ecs->stepping_through_solib_after_catch = 1; |
| 2774 | |
| 2775 | /* Be sure to lift all breakpoints, so the inferior does |
| 2776 | actually step past this point... */ |
| 2777 | ecs->stepping_over_breakpoint = 1; |
| 2778 | break; |
| 2779 | } |
| 2780 | else |
| 2781 | { |
| 2782 | /* We want to step over this breakpoint, then keep going. */ |
| 2783 | ecs->stepping_over_breakpoint = 1; |
| 2784 | break; |
| 2785 | } |
| 2786 | } |
| 2787 | break; |
| 2788 | |
| 2789 | case BPSTAT_WHAT_LAST: |
| 2790 | /* Not a real code, but listed here to shut up gcc -Wall. */ |
| 2791 | |
| 2792 | case BPSTAT_WHAT_KEEP_CHECKING: |
| 2793 | break; |
| 2794 | } |
| 2795 | } |
| 2796 | |
| 2797 | /* We come here if we hit a breakpoint but should not |
| 2798 | stop for it. Possibly we also were stepping |
| 2799 | and should stop for that. So fall through and |
| 2800 | test for stepping. But, if not stepping, |
| 2801 | do not stop. */ |
| 2802 | |
| 2803 | /* Are we stepping to get the inferior out of the dynamic linker's |
| 2804 | hook (and possibly the dld itself) after catching a shlib |
| 2805 | event? */ |
| 2806 | if (ecs->stepping_through_solib_after_catch) |
| 2807 | { |
| 2808 | #if defined(SOLIB_ADD) |
| 2809 | /* Have we reached our destination? If not, keep going. */ |
| 2810 | if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc)) |
| 2811 | { |
| 2812 | if (debug_infrun) |
| 2813 | fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n"); |
| 2814 | ecs->stepping_over_breakpoint = 1; |
| 2815 | keep_going (ecs); |
| 2816 | return; |
| 2817 | } |
| 2818 | #endif |
| 2819 | if (debug_infrun) |
| 2820 | fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n"); |
| 2821 | /* Else, stop and report the catchpoint(s) whose triggering |
| 2822 | caused us to begin stepping. */ |
| 2823 | ecs->stepping_through_solib_after_catch = 0; |
| 2824 | bpstat_clear (&stop_bpstat); |
| 2825 | stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints); |
| 2826 | bpstat_clear (&ecs->stepping_through_solib_catchpoints); |
| 2827 | stop_print_frame = 1; |
| 2828 | stop_stepping (ecs); |
| 2829 | return; |
| 2830 | } |
| 2831 | |
| 2832 | if (step_resume_breakpoint) |
| 2833 | { |
| 2834 | if (debug_infrun) |
| 2835 | fprintf_unfiltered (gdb_stdlog, |
| 2836 | "infrun: step-resume breakpoint is inserted\n"); |
| 2837 | |
| 2838 | /* Having a step-resume breakpoint overrides anything |
| 2839 | else having to do with stepping commands until |
| 2840 | that breakpoint is reached. */ |
| 2841 | keep_going (ecs); |
| 2842 | return; |
| 2843 | } |
| 2844 | |
| 2845 | if (step_range_end == 0) |
| 2846 | { |
| 2847 | if (debug_infrun) |
| 2848 | fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n"); |
| 2849 | /* Likewise if we aren't even stepping. */ |
| 2850 | keep_going (ecs); |
| 2851 | return; |
| 2852 | } |
| 2853 | |
| 2854 | /* If stepping through a line, keep going if still within it. |
| 2855 | |
| 2856 | Note that step_range_end is the address of the first instruction |
| 2857 | beyond the step range, and NOT the address of the last instruction |
| 2858 | within it! */ |
| 2859 | if (stop_pc >= step_range_start && stop_pc < step_range_end) |
| 2860 | { |
| 2861 | if (debug_infrun) |
| 2862 | fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n", |
| 2863 | paddr_nz (step_range_start), |
| 2864 | paddr_nz (step_range_end)); |
| 2865 | keep_going (ecs); |
| 2866 | return; |
| 2867 | } |
| 2868 | |
| 2869 | /* We stepped out of the stepping range. */ |
| 2870 | |
| 2871 | /* If we are stepping at the source level and entered the runtime |
| 2872 | loader dynamic symbol resolution code, we keep on single stepping |
| 2873 | until we exit the run time loader code and reach the callee's |
| 2874 | address. */ |
| 2875 | if (step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 2876 | #ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE |
| 2877 | && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc) |
| 2878 | #else |
| 2879 | && in_solib_dynsym_resolve_code (stop_pc) |
| 2880 | #endif |
| 2881 | ) |
| 2882 | { |
| 2883 | CORE_ADDR pc_after_resolver = |
| 2884 | gdbarch_skip_solib_resolver (current_gdbarch, stop_pc); |
| 2885 | |
| 2886 | if (debug_infrun) |
| 2887 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n"); |
| 2888 | |
| 2889 | if (pc_after_resolver) |
| 2890 | { |
| 2891 | /* Set up a step-resume breakpoint at the address |
| 2892 | indicated by SKIP_SOLIB_RESOLVER. */ |
| 2893 | struct symtab_and_line sr_sal; |
| 2894 | init_sal (&sr_sal); |
| 2895 | sr_sal.pc = pc_after_resolver; |
| 2896 | |
| 2897 | insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); |
| 2898 | } |
| 2899 | |
| 2900 | keep_going (ecs); |
| 2901 | return; |
| 2902 | } |
| 2903 | |
| 2904 | if (step_range_end != 1 |
| 2905 | && (step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 2906 | || step_over_calls == STEP_OVER_ALL) |
| 2907 | && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME) |
| 2908 | { |
| 2909 | if (debug_infrun) |
| 2910 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n"); |
| 2911 | /* The inferior, while doing a "step" or "next", has ended up in |
| 2912 | a signal trampoline (either by a signal being delivered or by |
| 2913 | the signal handler returning). Just single-step until the |
| 2914 | inferior leaves the trampoline (either by calling the handler |
| 2915 | or returning). */ |
| 2916 | keep_going (ecs); |
| 2917 | return; |
| 2918 | } |
| 2919 | |
| 2920 | /* Check for subroutine calls. The check for the current frame |
| 2921 | equalling the step ID is not necessary - the check of the |
| 2922 | previous frame's ID is sufficient - but it is a common case and |
| 2923 | cheaper than checking the previous frame's ID. |
| 2924 | |
| 2925 | NOTE: frame_id_eq will never report two invalid frame IDs as |
| 2926 | being equal, so to get into this block, both the current and |
| 2927 | previous frame must have valid frame IDs. */ |
| 2928 | if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id) |
| 2929 | && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id)) |
| 2930 | { |
| 2931 | CORE_ADDR real_stop_pc; |
| 2932 | |
| 2933 | if (debug_infrun) |
| 2934 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n"); |
| 2935 | |
| 2936 | if ((step_over_calls == STEP_OVER_NONE) |
| 2937 | || ((step_range_end == 1) |
| 2938 | && in_prologue (prev_pc, ecs->stop_func_start))) |
| 2939 | { |
| 2940 | /* I presume that step_over_calls is only 0 when we're |
| 2941 | supposed to be stepping at the assembly language level |
| 2942 | ("stepi"). Just stop. */ |
| 2943 | /* Also, maybe we just did a "nexti" inside a prolog, so we |
| 2944 | thought it was a subroutine call but it was not. Stop as |
| 2945 | well. FENN */ |
| 2946 | stop_step = 1; |
| 2947 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 2948 | stop_stepping (ecs); |
| 2949 | return; |
| 2950 | } |
| 2951 | |
| 2952 | if (step_over_calls == STEP_OVER_ALL) |
| 2953 | { |
| 2954 | /* We're doing a "next", set a breakpoint at callee's return |
| 2955 | address (the address at which the caller will |
| 2956 | resume). */ |
| 2957 | insert_step_resume_breakpoint_at_caller (get_current_frame ()); |
| 2958 | keep_going (ecs); |
| 2959 | return; |
| 2960 | } |
| 2961 | |
| 2962 | /* If we are in a function call trampoline (a stub between the |
| 2963 | calling routine and the real function), locate the real |
| 2964 | function. That's what tells us (a) whether we want to step |
| 2965 | into it at all, and (b) what prologue we want to run to the |
| 2966 | end of, if we do step into it. */ |
| 2967 | real_stop_pc = skip_language_trampoline (get_current_frame (), stop_pc); |
| 2968 | if (real_stop_pc == 0) |
| 2969 | real_stop_pc = gdbarch_skip_trampoline_code |
| 2970 | (current_gdbarch, get_current_frame (), stop_pc); |
| 2971 | if (real_stop_pc != 0) |
| 2972 | ecs->stop_func_start = real_stop_pc; |
| 2973 | |
| 2974 | if ( |
| 2975 | #ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE |
| 2976 | IN_SOLIB_DYNSYM_RESOLVE_CODE (ecs->stop_func_start) |
| 2977 | #else |
| 2978 | in_solib_dynsym_resolve_code (ecs->stop_func_start) |
| 2979 | #endif |
| 2980 | ) |
| 2981 | { |
| 2982 | struct symtab_and_line sr_sal; |
| 2983 | init_sal (&sr_sal); |
| 2984 | sr_sal.pc = ecs->stop_func_start; |
| 2985 | |
| 2986 | insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); |
| 2987 | keep_going (ecs); |
| 2988 | return; |
| 2989 | } |
| 2990 | |
| 2991 | /* If we have line number information for the function we are |
| 2992 | thinking of stepping into, step into it. |
| 2993 | |
| 2994 | If there are several symtabs at that PC (e.g. with include |
| 2995 | files), just want to know whether *any* of them have line |
| 2996 | numbers. find_pc_line handles this. */ |
| 2997 | { |
| 2998 | struct symtab_and_line tmp_sal; |
| 2999 | |
| 3000 | tmp_sal = find_pc_line (ecs->stop_func_start, 0); |
| 3001 | if (tmp_sal.line != 0) |
| 3002 | { |
| 3003 | step_into_function (ecs); |
| 3004 | return; |
| 3005 | } |
| 3006 | } |
| 3007 | |
| 3008 | /* If we have no line number and the step-stop-if-no-debug is |
| 3009 | set, we stop the step so that the user has a chance to switch |
| 3010 | in assembly mode. */ |
| 3011 | if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug) |
| 3012 | { |
| 3013 | stop_step = 1; |
| 3014 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3015 | stop_stepping (ecs); |
| 3016 | return; |
| 3017 | } |
| 3018 | |
| 3019 | /* Set a breakpoint at callee's return address (the address at |
| 3020 | which the caller will resume). */ |
| 3021 | insert_step_resume_breakpoint_at_caller (get_current_frame ()); |
| 3022 | keep_going (ecs); |
| 3023 | return; |
| 3024 | } |
| 3025 | |
| 3026 | /* If we're in the return path from a shared library trampoline, |
| 3027 | we want to proceed through the trampoline when stepping. */ |
| 3028 | if (gdbarch_in_solib_return_trampoline (current_gdbarch, |
| 3029 | stop_pc, ecs->stop_func_name)) |
| 3030 | { |
| 3031 | /* Determine where this trampoline returns. */ |
| 3032 | CORE_ADDR real_stop_pc; |
| 3033 | real_stop_pc = gdbarch_skip_trampoline_code |
| 3034 | (current_gdbarch, get_current_frame (), stop_pc); |
| 3035 | |
| 3036 | if (debug_infrun) |
| 3037 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n"); |
| 3038 | |
| 3039 | /* Only proceed through if we know where it's going. */ |
| 3040 | if (real_stop_pc) |
| 3041 | { |
| 3042 | /* And put the step-breakpoint there and go until there. */ |
| 3043 | struct symtab_and_line sr_sal; |
| 3044 | |
| 3045 | init_sal (&sr_sal); /* initialize to zeroes */ |
| 3046 | sr_sal.pc = real_stop_pc; |
| 3047 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 3048 | |
| 3049 | /* Do not specify what the fp should be when we stop since |
| 3050 | on some machines the prologue is where the new fp value |
| 3051 | is established. */ |
| 3052 | insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); |
| 3053 | |
| 3054 | /* Restart without fiddling with the step ranges or |
| 3055 | other state. */ |
| 3056 | keep_going (ecs); |
| 3057 | return; |
| 3058 | } |
| 3059 | } |
| 3060 | |
| 3061 | ecs->sal = find_pc_line (stop_pc, 0); |
| 3062 | |
| 3063 | /* NOTE: tausq/2004-05-24: This if block used to be done before all |
| 3064 | the trampoline processing logic, however, there are some trampolines |
| 3065 | that have no names, so we should do trampoline handling first. */ |
| 3066 | if (step_over_calls == STEP_OVER_UNDEBUGGABLE |
| 3067 | && ecs->stop_func_name == NULL |
| 3068 | && ecs->sal.line == 0) |
| 3069 | { |
| 3070 | if (debug_infrun) |
| 3071 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n"); |
| 3072 | |
| 3073 | /* The inferior just stepped into, or returned to, an |
| 3074 | undebuggable function (where there is no debugging information |
| 3075 | and no line number corresponding to the address where the |
| 3076 | inferior stopped). Since we want to skip this kind of code, |
| 3077 | we keep going until the inferior returns from this |
| 3078 | function - unless the user has asked us not to (via |
| 3079 | set step-mode) or we no longer know how to get back |
| 3080 | to the call site. */ |
| 3081 | if (step_stop_if_no_debug |
| 3082 | || !frame_id_p (frame_unwind_id (get_current_frame ()))) |
| 3083 | { |
| 3084 | /* If we have no line number and the step-stop-if-no-debug |
| 3085 | is set, we stop the step so that the user has a chance to |
| 3086 | switch in assembly mode. */ |
| 3087 | stop_step = 1; |
| 3088 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3089 | stop_stepping (ecs); |
| 3090 | return; |
| 3091 | } |
| 3092 | else |
| 3093 | { |
| 3094 | /* Set a breakpoint at callee's return address (the address |
| 3095 | at which the caller will resume). */ |
| 3096 | insert_step_resume_breakpoint_at_caller (get_current_frame ()); |
| 3097 | keep_going (ecs); |
| 3098 | return; |
| 3099 | } |
| 3100 | } |
| 3101 | |
| 3102 | if (step_range_end == 1) |
| 3103 | { |
| 3104 | /* It is stepi or nexti. We always want to stop stepping after |
| 3105 | one instruction. */ |
| 3106 | if (debug_infrun) |
| 3107 | fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n"); |
| 3108 | stop_step = 1; |
| 3109 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3110 | stop_stepping (ecs); |
| 3111 | return; |
| 3112 | } |
| 3113 | |
| 3114 | if (ecs->sal.line == 0) |
| 3115 | { |
| 3116 | /* We have no line number information. That means to stop |
| 3117 | stepping (does this always happen right after one instruction, |
| 3118 | when we do "s" in a function with no line numbers, |
| 3119 | or can this happen as a result of a return or longjmp?). */ |
| 3120 | if (debug_infrun) |
| 3121 | fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n"); |
| 3122 | stop_step = 1; |
| 3123 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3124 | stop_stepping (ecs); |
| 3125 | return; |
| 3126 | } |
| 3127 | |
| 3128 | if ((stop_pc == ecs->sal.pc) |
| 3129 | && (ecs->current_line != ecs->sal.line |
| 3130 | || ecs->current_symtab != ecs->sal.symtab)) |
| 3131 | { |
| 3132 | /* We are at the start of a different line. So stop. Note that |
| 3133 | we don't stop if we step into the middle of a different line. |
| 3134 | That is said to make things like for (;;) statements work |
| 3135 | better. */ |
| 3136 | if (debug_infrun) |
| 3137 | fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n"); |
| 3138 | stop_step = 1; |
| 3139 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3140 | stop_stepping (ecs); |
| 3141 | return; |
| 3142 | } |
| 3143 | |
| 3144 | /* We aren't done stepping. |
| 3145 | |
| 3146 | Optimize by setting the stepping range to the line. |
| 3147 | (We might not be in the original line, but if we entered a |
| 3148 | new line in mid-statement, we continue stepping. This makes |
| 3149 | things like for(;;) statements work better.) */ |
| 3150 | |
| 3151 | step_range_start = ecs->sal.pc; |
| 3152 | step_range_end = ecs->sal.end; |
| 3153 | step_frame_id = get_frame_id (get_current_frame ()); |
| 3154 | ecs->current_line = ecs->sal.line; |
| 3155 | ecs->current_symtab = ecs->sal.symtab; |
| 3156 | |
| 3157 | /* In the case where we just stepped out of a function into the |
| 3158 | middle of a line of the caller, continue stepping, but |
| 3159 | step_frame_id must be modified to current frame */ |
| 3160 | #if 0 |
| 3161 | /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too |
| 3162 | generous. It will trigger on things like a step into a frameless |
| 3163 | stackless leaf function. I think the logic should instead look |
| 3164 | at the unwound frame ID has that should give a more robust |
| 3165 | indication of what happened. */ |
| 3166 | if (step - ID == current - ID) |
| 3167 | still stepping in same function; |
| 3168 | else if (step - ID == unwind (current - ID)) |
| 3169 | stepped into a function; |
| 3170 | else |
| 3171 | stepped out of a function; |
| 3172 | /* Of course this assumes that the frame ID unwind code is robust |
| 3173 | and we're willing to introduce frame unwind logic into this |
| 3174 | function. Fortunately, those days are nearly upon us. */ |
| 3175 | #endif |
| 3176 | { |
| 3177 | struct frame_info *frame = get_current_frame (); |
| 3178 | struct frame_id current_frame = get_frame_id (frame); |
| 3179 | if (!(frame_id_inner (get_frame_arch (frame), current_frame, |
| 3180 | step_frame_id))) |
| 3181 | step_frame_id = current_frame; |
| 3182 | } |
| 3183 | |
| 3184 | if (debug_infrun) |
| 3185 | fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n"); |
| 3186 | keep_going (ecs); |
| 3187 | } |
| 3188 | |
| 3189 | /* Are we in the middle of stepping? */ |
| 3190 | |
| 3191 | static int |
| 3192 | currently_stepping (struct execution_control_state *ecs) |
| 3193 | { |
| 3194 | return (((step_range_end && step_resume_breakpoint == NULL) |
| 3195 | || stepping_over_breakpoint) |
| 3196 | || ecs->stepping_through_solib_after_catch |
| 3197 | || bpstat_should_step ()); |
| 3198 | } |
| 3199 | |
| 3200 | /* Subroutine call with source code we should not step over. Do step |
| 3201 | to the first line of code in it. */ |
| 3202 | |
| 3203 | static void |
| 3204 | step_into_function (struct execution_control_state *ecs) |
| 3205 | { |
| 3206 | struct symtab *s; |
| 3207 | struct symtab_and_line sr_sal; |
| 3208 | |
| 3209 | s = find_pc_symtab (stop_pc); |
| 3210 | if (s && s->language != language_asm) |
| 3211 | ecs->stop_func_start = gdbarch_skip_prologue |
| 3212 | (current_gdbarch, ecs->stop_func_start); |
| 3213 | |
| 3214 | ecs->sal = find_pc_line (ecs->stop_func_start, 0); |
| 3215 | /* Use the step_resume_break to step until the end of the prologue, |
| 3216 | even if that involves jumps (as it seems to on the vax under |
| 3217 | 4.2). */ |
| 3218 | /* If the prologue ends in the middle of a source line, continue to |
| 3219 | the end of that source line (if it is still within the function). |
| 3220 | Otherwise, just go to end of prologue. */ |
| 3221 | if (ecs->sal.end |
| 3222 | && ecs->sal.pc != ecs->stop_func_start |
| 3223 | && ecs->sal.end < ecs->stop_func_end) |
| 3224 | ecs->stop_func_start = ecs->sal.end; |
| 3225 | |
| 3226 | /* Architectures which require breakpoint adjustment might not be able |
| 3227 | to place a breakpoint at the computed address. If so, the test |
| 3228 | ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust |
| 3229 | ecs->stop_func_start to an address at which a breakpoint may be |
| 3230 | legitimately placed. |
| 3231 | |
| 3232 | Note: kevinb/2004-01-19: On FR-V, if this adjustment is not |
| 3233 | made, GDB will enter an infinite loop when stepping through |
| 3234 | optimized code consisting of VLIW instructions which contain |
| 3235 | subinstructions corresponding to different source lines. On |
| 3236 | FR-V, it's not permitted to place a breakpoint on any but the |
| 3237 | first subinstruction of a VLIW instruction. When a breakpoint is |
| 3238 | set, GDB will adjust the breakpoint address to the beginning of |
| 3239 | the VLIW instruction. Thus, we need to make the corresponding |
| 3240 | adjustment here when computing the stop address. */ |
| 3241 | |
| 3242 | if (gdbarch_adjust_breakpoint_address_p (current_gdbarch)) |
| 3243 | { |
| 3244 | ecs->stop_func_start |
| 3245 | = gdbarch_adjust_breakpoint_address (current_gdbarch, |
| 3246 | ecs->stop_func_start); |
| 3247 | } |
| 3248 | |
| 3249 | if (ecs->stop_func_start == stop_pc) |
| 3250 | { |
| 3251 | /* We are already there: stop now. */ |
| 3252 | stop_step = 1; |
| 3253 | print_stop_reason (END_STEPPING_RANGE, 0); |
| 3254 | stop_stepping (ecs); |
| 3255 | return; |
| 3256 | } |
| 3257 | else |
| 3258 | { |
| 3259 | /* Put the step-breakpoint there and go until there. */ |
| 3260 | init_sal (&sr_sal); /* initialize to zeroes */ |
| 3261 | sr_sal.pc = ecs->stop_func_start; |
| 3262 | sr_sal.section = find_pc_overlay (ecs->stop_func_start); |
| 3263 | |
| 3264 | /* Do not specify what the fp should be when we stop since on |
| 3265 | some machines the prologue is where the new fp value is |
| 3266 | established. */ |
| 3267 | insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id); |
| 3268 | |
| 3269 | /* And make sure stepping stops right away then. */ |
| 3270 | step_range_end = step_range_start; |
| 3271 | } |
| 3272 | keep_going (ecs); |
| 3273 | } |
| 3274 | |
| 3275 | /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID. |
| 3276 | This is used to both functions and to skip over code. */ |
| 3277 | |
| 3278 | static void |
| 3279 | insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal, |
| 3280 | struct frame_id sr_id) |
| 3281 | { |
| 3282 | /* There should never be more than one step-resume or longjmp-resume |
| 3283 | breakpoint per thread, so we should never be setting a new |
| 3284 | step_resume_breakpoint when one is already active. */ |
| 3285 | gdb_assert (step_resume_breakpoint == NULL); |
| 3286 | |
| 3287 | if (debug_infrun) |
| 3288 | fprintf_unfiltered (gdb_stdlog, |
| 3289 | "infrun: inserting step-resume breakpoint at 0x%s\n", |
| 3290 | paddr_nz (sr_sal.pc)); |
| 3291 | |
| 3292 | step_resume_breakpoint = set_momentary_breakpoint (sr_sal, sr_id, |
| 3293 | bp_step_resume); |
| 3294 | } |
| 3295 | |
| 3296 | /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used |
| 3297 | to skip a potential signal handler. |
| 3298 | |
| 3299 | This is called with the interrupted function's frame. The signal |
| 3300 | handler, when it returns, will resume the interrupted function at |
| 3301 | RETURN_FRAME.pc. */ |
| 3302 | |
| 3303 | static void |
| 3304 | insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame) |
| 3305 | { |
| 3306 | struct symtab_and_line sr_sal; |
| 3307 | |
| 3308 | gdb_assert (return_frame != NULL); |
| 3309 | init_sal (&sr_sal); /* initialize to zeros */ |
| 3310 | |
| 3311 | sr_sal.pc = gdbarch_addr_bits_remove |
| 3312 | (current_gdbarch, get_frame_pc (return_frame)); |
| 3313 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 3314 | |
| 3315 | insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame)); |
| 3316 | } |
| 3317 | |
| 3318 | /* Similar to insert_step_resume_breakpoint_at_frame, except |
| 3319 | but a breakpoint at the previous frame's PC. This is used to |
| 3320 | skip a function after stepping into it (for "next" or if the called |
| 3321 | function has no debugging information). |
| 3322 | |
| 3323 | The current function has almost always been reached by single |
| 3324 | stepping a call or return instruction. NEXT_FRAME belongs to the |
| 3325 | current function, and the breakpoint will be set at the caller's |
| 3326 | resume address. |
| 3327 | |
| 3328 | This is a separate function rather than reusing |
| 3329 | insert_step_resume_breakpoint_at_frame in order to avoid |
| 3330 | get_prev_frame, which may stop prematurely (see the implementation |
| 3331 | of frame_unwind_id for an example). */ |
| 3332 | |
| 3333 | static void |
| 3334 | insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame) |
| 3335 | { |
| 3336 | struct symtab_and_line sr_sal; |
| 3337 | |
| 3338 | /* We shouldn't have gotten here if we don't know where the call site |
| 3339 | is. */ |
| 3340 | gdb_assert (frame_id_p (frame_unwind_id (next_frame))); |
| 3341 | |
| 3342 | init_sal (&sr_sal); /* initialize to zeros */ |
| 3343 | |
| 3344 | sr_sal.pc = gdbarch_addr_bits_remove |
| 3345 | (current_gdbarch, frame_pc_unwind (next_frame)); |
| 3346 | sr_sal.section = find_pc_overlay (sr_sal.pc); |
| 3347 | |
| 3348 | insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame)); |
| 3349 | } |
| 3350 | |
| 3351 | /* Insert a "longjmp-resume" breakpoint at PC. This is used to set a |
| 3352 | new breakpoint at the target of a jmp_buf. The handling of |
| 3353 | longjmp-resume uses the same mechanisms used for handling |
| 3354 | "step-resume" breakpoints. */ |
| 3355 | |
| 3356 | static void |
| 3357 | insert_longjmp_resume_breakpoint (CORE_ADDR pc) |
| 3358 | { |
| 3359 | /* There should never be more than one step-resume or longjmp-resume |
| 3360 | breakpoint per thread, so we should never be setting a new |
| 3361 | longjmp_resume_breakpoint when one is already active. */ |
| 3362 | gdb_assert (step_resume_breakpoint == NULL); |
| 3363 | |
| 3364 | if (debug_infrun) |
| 3365 | fprintf_unfiltered (gdb_stdlog, |
| 3366 | "infrun: inserting longjmp-resume breakpoint at 0x%s\n", |
| 3367 | paddr_nz (pc)); |
| 3368 | |
| 3369 | step_resume_breakpoint = |
| 3370 | set_momentary_breakpoint_at_pc (pc, bp_longjmp_resume); |
| 3371 | } |
| 3372 | |
| 3373 | static void |
| 3374 | stop_stepping (struct execution_control_state *ecs) |
| 3375 | { |
| 3376 | if (debug_infrun) |
| 3377 | fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n"); |
| 3378 | |
| 3379 | /* Let callers know we don't want to wait for the inferior anymore. */ |
| 3380 | ecs->wait_some_more = 0; |
| 3381 | } |
| 3382 | |
| 3383 | /* This function handles various cases where we need to continue |
| 3384 | waiting for the inferior. */ |
| 3385 | /* (Used to be the keep_going: label in the old wait_for_inferior) */ |
| 3386 | |
| 3387 | static void |
| 3388 | keep_going (struct execution_control_state *ecs) |
| 3389 | { |
| 3390 | /* Save the pc before execution, to compare with pc after stop. */ |
| 3391 | prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */ |
| 3392 | |
| 3393 | /* If we did not do break;, it means we should keep running the |
| 3394 | inferior and not return to debugger. */ |
| 3395 | |
| 3396 | if (stepping_over_breakpoint && stop_signal != TARGET_SIGNAL_TRAP) |
| 3397 | { |
| 3398 | /* We took a signal (which we are supposed to pass through to |
| 3399 | the inferior, else we'd have done a break above) and we |
| 3400 | haven't yet gotten our trap. Simply continue. */ |
| 3401 | resume (currently_stepping (ecs), stop_signal); |
| 3402 | } |
| 3403 | else |
| 3404 | { |
| 3405 | /* Either the trap was not expected, but we are continuing |
| 3406 | anyway (the user asked that this signal be passed to the |
| 3407 | child) |
| 3408 | -- or -- |
| 3409 | The signal was SIGTRAP, e.g. it was our signal, but we |
| 3410 | decided we should resume from it. |
| 3411 | |
| 3412 | We're going to run this baby now! |
| 3413 | |
| 3414 | Note that insert_breakpoints won't try to re-insert |
| 3415 | already inserted breakpoints. Therefore, we don't |
| 3416 | care if breakpoints were already inserted, or not. */ |
| 3417 | |
| 3418 | if (ecs->stepping_over_breakpoint) |
| 3419 | { |
| 3420 | if (! use_displaced_stepping (current_gdbarch)) |
| 3421 | /* Since we can't do a displaced step, we have to remove |
| 3422 | the breakpoint while we step it. To keep things |
| 3423 | simple, we remove them all. */ |
| 3424 | remove_breakpoints (); |
| 3425 | } |
| 3426 | else |
| 3427 | { |
| 3428 | struct gdb_exception e; |
| 3429 | /* Stop stepping when inserting breakpoints |
| 3430 | has failed. */ |
| 3431 | TRY_CATCH (e, RETURN_MASK_ERROR) |
| 3432 | { |
| 3433 | insert_breakpoints (); |
| 3434 | } |
| 3435 | if (e.reason < 0) |
| 3436 | { |
| 3437 | stop_stepping (ecs); |
| 3438 | return; |
| 3439 | } |
| 3440 | } |
| 3441 | |
| 3442 | stepping_over_breakpoint = ecs->stepping_over_breakpoint; |
| 3443 | |
| 3444 | /* Do not deliver SIGNAL_TRAP (except when the user explicitly |
| 3445 | specifies that such a signal should be delivered to the |
| 3446 | target program). |
| 3447 | |
| 3448 | Typically, this would occure when a user is debugging a |
| 3449 | target monitor on a simulator: the target monitor sets a |
| 3450 | breakpoint; the simulator encounters this break-point and |
| 3451 | halts the simulation handing control to GDB; GDB, noteing |
| 3452 | that the break-point isn't valid, returns control back to the |
| 3453 | simulator; the simulator then delivers the hardware |
| 3454 | equivalent of a SIGNAL_TRAP to the program being debugged. */ |
| 3455 | |
| 3456 | if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal]) |
| 3457 | stop_signal = TARGET_SIGNAL_0; |
| 3458 | |
| 3459 | |
| 3460 | resume (currently_stepping (ecs), stop_signal); |
| 3461 | } |
| 3462 | |
| 3463 | prepare_to_wait (ecs); |
| 3464 | } |
| 3465 | |
| 3466 | /* This function normally comes after a resume, before |
| 3467 | handle_inferior_event exits. It takes care of any last bits of |
| 3468 | housekeeping, and sets the all-important wait_some_more flag. */ |
| 3469 | |
| 3470 | static void |
| 3471 | prepare_to_wait (struct execution_control_state *ecs) |
| 3472 | { |
| 3473 | if (debug_infrun) |
| 3474 | fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n"); |
| 3475 | if (ecs->infwait_state == infwait_normal_state) |
| 3476 | { |
| 3477 | overlay_cache_invalid = 1; |
| 3478 | |
| 3479 | /* We have to invalidate the registers BEFORE calling |
| 3480 | target_wait because they can be loaded from the target while |
| 3481 | in target_wait. This makes remote debugging a bit more |
| 3482 | efficient for those targets that provide critical registers |
| 3483 | as part of their normal status mechanism. */ |
| 3484 | |
| 3485 | registers_changed (); |
| 3486 | ecs->waiton_ptid = pid_to_ptid (-1); |
| 3487 | ecs->wp = &(ecs->ws); |
| 3488 | } |
| 3489 | /* This is the old end of the while loop. Let everybody know we |
| 3490 | want to wait for the inferior some more and get called again |
| 3491 | soon. */ |
| 3492 | ecs->wait_some_more = 1; |
| 3493 | } |
| 3494 | |
| 3495 | /* Print why the inferior has stopped. We always print something when |
| 3496 | the inferior exits, or receives a signal. The rest of the cases are |
| 3497 | dealt with later on in normal_stop() and print_it_typical(). Ideally |
| 3498 | there should be a call to this function from handle_inferior_event() |
| 3499 | each time stop_stepping() is called.*/ |
| 3500 | static void |
| 3501 | print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info) |
| 3502 | { |
| 3503 | switch (stop_reason) |
| 3504 | { |
| 3505 | case END_STEPPING_RANGE: |
| 3506 | /* We are done with a step/next/si/ni command. */ |
| 3507 | /* For now print nothing. */ |
| 3508 | /* Print a message only if not in the middle of doing a "step n" |
| 3509 | operation for n > 1 */ |
| 3510 | if (!step_multi || !stop_step) |
| 3511 | if (ui_out_is_mi_like_p (uiout)) |
| 3512 | ui_out_field_string |
| 3513 | (uiout, "reason", |
| 3514 | async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE)); |
| 3515 | break; |
| 3516 | case SIGNAL_EXITED: |
| 3517 | /* The inferior was terminated by a signal. */ |
| 3518 | annotate_signalled (); |
| 3519 | if (ui_out_is_mi_like_p (uiout)) |
| 3520 | ui_out_field_string |
| 3521 | (uiout, "reason", |
| 3522 | async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED)); |
| 3523 | ui_out_text (uiout, "\nProgram terminated with signal "); |
| 3524 | annotate_signal_name (); |
| 3525 | ui_out_field_string (uiout, "signal-name", |
| 3526 | target_signal_to_name (stop_info)); |
| 3527 | annotate_signal_name_end (); |
| 3528 | ui_out_text (uiout, ", "); |
| 3529 | annotate_signal_string (); |
| 3530 | ui_out_field_string (uiout, "signal-meaning", |
| 3531 | target_signal_to_string (stop_info)); |
| 3532 | annotate_signal_string_end (); |
| 3533 | ui_out_text (uiout, ".\n"); |
| 3534 | ui_out_text (uiout, "The program no longer exists.\n"); |
| 3535 | break; |
| 3536 | case EXITED: |
| 3537 | /* The inferior program is finished. */ |
| 3538 | annotate_exited (stop_info); |
| 3539 | if (stop_info) |
| 3540 | { |
| 3541 | if (ui_out_is_mi_like_p (uiout)) |
| 3542 | ui_out_field_string (uiout, "reason", |
| 3543 | async_reason_lookup (EXEC_ASYNC_EXITED)); |
| 3544 | ui_out_text (uiout, "\nProgram exited with code "); |
| 3545 | ui_out_field_fmt (uiout, "exit-code", "0%o", |
| 3546 | (unsigned int) stop_info); |
| 3547 | ui_out_text (uiout, ".\n"); |
| 3548 | } |
| 3549 | else |
| 3550 | { |
| 3551 | if (ui_out_is_mi_like_p (uiout)) |
| 3552 | ui_out_field_string |
| 3553 | (uiout, "reason", |
| 3554 | async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY)); |
| 3555 | ui_out_text (uiout, "\nProgram exited normally.\n"); |
| 3556 | } |
| 3557 | /* Support the --return-child-result option. */ |
| 3558 | return_child_result_value = stop_info; |
| 3559 | break; |
| 3560 | case SIGNAL_RECEIVED: |
| 3561 | /* Signal received. The signal table tells us to print about |
| 3562 | it. */ |
| 3563 | annotate_signal (); |
| 3564 | ui_out_text (uiout, "\nProgram received signal "); |
| 3565 | annotate_signal_name (); |
| 3566 | if (ui_out_is_mi_like_p (uiout)) |
| 3567 | ui_out_field_string |
| 3568 | (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED)); |
| 3569 | ui_out_field_string (uiout, "signal-name", |
| 3570 | target_signal_to_name (stop_info)); |
| 3571 | annotate_signal_name_end (); |
| 3572 | ui_out_text (uiout, ", "); |
| 3573 | annotate_signal_string (); |
| 3574 | ui_out_field_string (uiout, "signal-meaning", |
| 3575 | target_signal_to_string (stop_info)); |
| 3576 | annotate_signal_string_end (); |
| 3577 | ui_out_text (uiout, ".\n"); |
| 3578 | break; |
| 3579 | default: |
| 3580 | internal_error (__FILE__, __LINE__, |
| 3581 | _("print_stop_reason: unrecognized enum value")); |
| 3582 | break; |
| 3583 | } |
| 3584 | } |
| 3585 | \f |
| 3586 | |
| 3587 | /* Here to return control to GDB when the inferior stops for real. |
| 3588 | Print appropriate messages, remove breakpoints, give terminal our modes. |
| 3589 | |
| 3590 | STOP_PRINT_FRAME nonzero means print the executing frame |
| 3591 | (pc, function, args, file, line number and line text). |
| 3592 | BREAKPOINTS_FAILED nonzero means stop was due to error |
| 3593 | attempting to insert breakpoints. */ |
| 3594 | |
| 3595 | void |
| 3596 | normal_stop (void) |
| 3597 | { |
| 3598 | struct target_waitstatus last; |
| 3599 | ptid_t last_ptid; |
| 3600 | |
| 3601 | get_last_target_status (&last_ptid, &last); |
| 3602 | |
| 3603 | /* As with the notification of thread events, we want to delay |
| 3604 | notifying the user that we've switched thread context until |
| 3605 | the inferior actually stops. |
| 3606 | |
| 3607 | There's no point in saying anything if the inferior has exited. |
| 3608 | Note that SIGNALLED here means "exited with a signal", not |
| 3609 | "received a signal". */ |
| 3610 | if (!ptid_equal (previous_inferior_ptid, inferior_ptid) |
| 3611 | && target_has_execution |
| 3612 | && last.kind != TARGET_WAITKIND_SIGNALLED |
| 3613 | && last.kind != TARGET_WAITKIND_EXITED) |
| 3614 | { |
| 3615 | target_terminal_ours_for_output (); |
| 3616 | printf_filtered (_("[Switching to %s]\n"), |
| 3617 | target_pid_to_str (inferior_ptid)); |
| 3618 | annotate_thread_changed (); |
| 3619 | previous_inferior_ptid = inferior_ptid; |
| 3620 | } |
| 3621 | |
| 3622 | /* NOTE drow/2004-01-17: Is this still necessary? */ |
| 3623 | /* Make sure that the current_frame's pc is correct. This |
| 3624 | is a correction for setting up the frame info before doing |
| 3625 | gdbarch_decr_pc_after_break */ |
| 3626 | if (target_has_execution) |
| 3627 | /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to |
| 3628 | gdbarch_decr_pc_after_break, the program counter can change. Ask the |
| 3629 | frame code to check for this and sort out any resultant mess. |
| 3630 | gdbarch_decr_pc_after_break needs to just go away. */ |
| 3631 | deprecated_update_frame_pc_hack (get_current_frame (), read_pc ()); |
| 3632 | |
| 3633 | if (!breakpoints_always_inserted_mode () && target_has_execution) |
| 3634 | { |
| 3635 | if (remove_breakpoints ()) |
| 3636 | { |
| 3637 | target_terminal_ours_for_output (); |
| 3638 | printf_filtered (_("\ |
| 3639 | Cannot remove breakpoints because program is no longer writable.\n\ |
| 3640 | It might be running in another process.\n\ |
| 3641 | Further execution is probably impossible.\n")); |
| 3642 | } |
| 3643 | } |
| 3644 | |
| 3645 | /* If an auto-display called a function and that got a signal, |
| 3646 | delete that auto-display to avoid an infinite recursion. */ |
| 3647 | |
| 3648 | if (stopped_by_random_signal) |
| 3649 | disable_current_display (); |
| 3650 | |
| 3651 | /* Don't print a message if in the middle of doing a "step n" |
| 3652 | operation for n > 1 */ |
| 3653 | if (step_multi && stop_step) |
| 3654 | goto done; |
| 3655 | |
| 3656 | target_terminal_ours (); |
| 3657 | |
| 3658 | /* Set the current source location. This will also happen if we |
| 3659 | display the frame below, but the current SAL will be incorrect |
| 3660 | during a user hook-stop function. */ |
| 3661 | if (target_has_stack && !stop_stack_dummy) |
| 3662 | set_current_sal_from_frame (get_current_frame (), 1); |
| 3663 | |
| 3664 | /* Look up the hook_stop and run it (CLI internally handles problem |
| 3665 | of stop_command's pre-hook not existing). */ |
| 3666 | if (stop_command) |
| 3667 | catch_errors (hook_stop_stub, stop_command, |
| 3668 | "Error while running hook_stop:\n", RETURN_MASK_ALL); |
| 3669 | |
| 3670 | if (!target_has_stack) |
| 3671 | { |
| 3672 | |
| 3673 | goto done; |
| 3674 | } |
| 3675 | |
| 3676 | /* Select innermost stack frame - i.e., current frame is frame 0, |
| 3677 | and current location is based on that. |
| 3678 | Don't do this on return from a stack dummy routine, |
| 3679 | or if the program has exited. */ |
| 3680 | |
| 3681 | if (!stop_stack_dummy) |
| 3682 | { |
| 3683 | select_frame (get_current_frame ()); |
| 3684 | |
| 3685 | /* Print current location without a level number, if |
| 3686 | we have changed functions or hit a breakpoint. |
| 3687 | Print source line if we have one. |
| 3688 | bpstat_print() contains the logic deciding in detail |
| 3689 | what to print, based on the event(s) that just occurred. */ |
| 3690 | |
| 3691 | /* If --batch-silent is enabled then there's no need to print the current |
| 3692 | source location, and to try risks causing an error message about |
| 3693 | missing source files. */ |
| 3694 | if (stop_print_frame && !batch_silent) |
| 3695 | { |
| 3696 | int bpstat_ret; |
| 3697 | int source_flag; |
| 3698 | int do_frame_printing = 1; |
| 3699 | |
| 3700 | bpstat_ret = bpstat_print (stop_bpstat); |
| 3701 | switch (bpstat_ret) |
| 3702 | { |
| 3703 | case PRINT_UNKNOWN: |
| 3704 | /* If we had hit a shared library event breakpoint, |
| 3705 | bpstat_print would print out this message. If we hit |
| 3706 | an OS-level shared library event, do the same |
| 3707 | thing. */ |
| 3708 | if (last.kind == TARGET_WAITKIND_LOADED) |
| 3709 | { |
| 3710 | printf_filtered (_("Stopped due to shared library event\n")); |
| 3711 | source_flag = SRC_LINE; /* something bogus */ |
| 3712 | do_frame_printing = 0; |
| 3713 | break; |
| 3714 | } |
| 3715 | |
| 3716 | /* FIXME: cagney/2002-12-01: Given that a frame ID does |
| 3717 | (or should) carry around the function and does (or |
| 3718 | should) use that when doing a frame comparison. */ |
| 3719 | if (stop_step |
| 3720 | && frame_id_eq (step_frame_id, |
| 3721 | get_frame_id (get_current_frame ())) |
| 3722 | && step_start_function == find_pc_function (stop_pc)) |
| 3723 | source_flag = SRC_LINE; /* finished step, just print source line */ |
| 3724 | else |
| 3725 | source_flag = SRC_AND_LOC; /* print location and source line */ |
| 3726 | break; |
| 3727 | case PRINT_SRC_AND_LOC: |
| 3728 | source_flag = SRC_AND_LOC; /* print location and source line */ |
| 3729 | break; |
| 3730 | case PRINT_SRC_ONLY: |
| 3731 | source_flag = SRC_LINE; |
| 3732 | break; |
| 3733 | case PRINT_NOTHING: |
| 3734 | source_flag = SRC_LINE; /* something bogus */ |
| 3735 | do_frame_printing = 0; |
| 3736 | break; |
| 3737 | default: |
| 3738 | internal_error (__FILE__, __LINE__, _("Unknown value.")); |
| 3739 | } |
| 3740 | |
| 3741 | if (ui_out_is_mi_like_p (uiout)) |
| 3742 | ui_out_field_int (uiout, "thread-id", |
| 3743 | pid_to_thread_id (inferior_ptid)); |
| 3744 | /* The behavior of this routine with respect to the source |
| 3745 | flag is: |
| 3746 | SRC_LINE: Print only source line |
| 3747 | LOCATION: Print only location |
| 3748 | SRC_AND_LOC: Print location and source line */ |
| 3749 | if (do_frame_printing) |
| 3750 | print_stack_frame (get_selected_frame (NULL), 0, source_flag); |
| 3751 | |
| 3752 | /* Display the auto-display expressions. */ |
| 3753 | do_displays (); |
| 3754 | } |
| 3755 | } |
| 3756 | |
| 3757 | /* Save the function value return registers, if we care. |
| 3758 | We might be about to restore their previous contents. */ |
| 3759 | if (proceed_to_finish) |
| 3760 | { |
| 3761 | /* This should not be necessary. */ |
| 3762 | if (stop_registers) |
| 3763 | regcache_xfree (stop_registers); |
| 3764 | |
| 3765 | /* NB: The copy goes through to the target picking up the value of |
| 3766 | all the registers. */ |
| 3767 | stop_registers = regcache_dup (get_current_regcache ()); |
| 3768 | } |
| 3769 | |
| 3770 | if (stop_stack_dummy) |
| 3771 | { |
| 3772 | /* Pop the empty frame that contains the stack dummy. POP_FRAME |
| 3773 | ends with a setting of the current frame, so we can use that |
| 3774 | next. */ |
| 3775 | frame_pop (get_current_frame ()); |
| 3776 | /* Set stop_pc to what it was before we called the function. |
| 3777 | Can't rely on restore_inferior_status because that only gets |
| 3778 | called if we don't stop in the called function. */ |
| 3779 | stop_pc = read_pc (); |
| 3780 | select_frame (get_current_frame ()); |
| 3781 | } |
| 3782 | |
| 3783 | done: |
| 3784 | annotate_stopped (); |
| 3785 | if (!suppress_stop_observer && !step_multi) |
| 3786 | observer_notify_normal_stop (stop_bpstat); |
| 3787 | /* Delete the breakpoint we stopped at, if it wants to be deleted. |
| 3788 | Delete any breakpoint that is to be deleted at the next stop. */ |
| 3789 | breakpoint_auto_delete (stop_bpstat); |
| 3790 | set_running (pid_to_ptid (-1), 0); |
| 3791 | } |
| 3792 | |
| 3793 | static int |
| 3794 | hook_stop_stub (void *cmd) |
| 3795 | { |
| 3796 | execute_cmd_pre_hook ((struct cmd_list_element *) cmd); |
| 3797 | return (0); |
| 3798 | } |
| 3799 | \f |
| 3800 | int |
| 3801 | signal_stop_state (int signo) |
| 3802 | { |
| 3803 | /* Always stop on signals if we're just gaining control of the |
| 3804 | program. */ |
| 3805 | return signal_stop[signo] || stop_soon != NO_STOP_QUIETLY; |
| 3806 | } |
| 3807 | |
| 3808 | int |
| 3809 | signal_print_state (int signo) |
| 3810 | { |
| 3811 | return signal_print[signo]; |
| 3812 | } |
| 3813 | |
| 3814 | int |
| 3815 | signal_pass_state (int signo) |
| 3816 | { |
| 3817 | return signal_program[signo]; |
| 3818 | } |
| 3819 | |
| 3820 | int |
| 3821 | signal_stop_update (int signo, int state) |
| 3822 | { |
| 3823 | int ret = signal_stop[signo]; |
| 3824 | signal_stop[signo] = state; |
| 3825 | return ret; |
| 3826 | } |
| 3827 | |
| 3828 | int |
| 3829 | signal_print_update (int signo, int state) |
| 3830 | { |
| 3831 | int ret = signal_print[signo]; |
| 3832 | signal_print[signo] = state; |
| 3833 | return ret; |
| 3834 | } |
| 3835 | |
| 3836 | int |
| 3837 | signal_pass_update (int signo, int state) |
| 3838 | { |
| 3839 | int ret = signal_program[signo]; |
| 3840 | signal_program[signo] = state; |
| 3841 | return ret; |
| 3842 | } |
| 3843 | |
| 3844 | static void |
| 3845 | sig_print_header (void) |
| 3846 | { |
| 3847 | printf_filtered (_("\ |
| 3848 | Signal Stop\tPrint\tPass to program\tDescription\n")); |
| 3849 | } |
| 3850 | |
| 3851 | static void |
| 3852 | sig_print_info (enum target_signal oursig) |
| 3853 | { |
| 3854 | char *name = target_signal_to_name (oursig); |
| 3855 | int name_padding = 13 - strlen (name); |
| 3856 | |
| 3857 | if (name_padding <= 0) |
| 3858 | name_padding = 0; |
| 3859 | |
| 3860 | printf_filtered ("%s", name); |
| 3861 | printf_filtered ("%*.*s ", name_padding, name_padding, " "); |
| 3862 | printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No"); |
| 3863 | printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No"); |
| 3864 | printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No"); |
| 3865 | printf_filtered ("%s\n", target_signal_to_string (oursig)); |
| 3866 | } |
| 3867 | |
| 3868 | /* Specify how various signals in the inferior should be handled. */ |
| 3869 | |
| 3870 | static void |
| 3871 | handle_command (char *args, int from_tty) |
| 3872 | { |
| 3873 | char **argv; |
| 3874 | int digits, wordlen; |
| 3875 | int sigfirst, signum, siglast; |
| 3876 | enum target_signal oursig; |
| 3877 | int allsigs; |
| 3878 | int nsigs; |
| 3879 | unsigned char *sigs; |
| 3880 | struct cleanup *old_chain; |
| 3881 | |
| 3882 | if (args == NULL) |
| 3883 | { |
| 3884 | error_no_arg (_("signal to handle")); |
| 3885 | } |
| 3886 | |
| 3887 | /* Allocate and zero an array of flags for which signals to handle. */ |
| 3888 | |
| 3889 | nsigs = (int) TARGET_SIGNAL_LAST; |
| 3890 | sigs = (unsigned char *) alloca (nsigs); |
| 3891 | memset (sigs, 0, nsigs); |
| 3892 | |
| 3893 | /* Break the command line up into args. */ |
| 3894 | |
| 3895 | argv = buildargv (args); |
| 3896 | if (argv == NULL) |
| 3897 | { |
| 3898 | nomem (0); |
| 3899 | } |
| 3900 | old_chain = make_cleanup_freeargv (argv); |
| 3901 | |
| 3902 | /* Walk through the args, looking for signal oursigs, signal names, and |
| 3903 | actions. Signal numbers and signal names may be interspersed with |
| 3904 | actions, with the actions being performed for all signals cumulatively |
| 3905 | specified. Signal ranges can be specified as <LOW>-<HIGH>. */ |
| 3906 | |
| 3907 | while (*argv != NULL) |
| 3908 | { |
| 3909 | wordlen = strlen (*argv); |
| 3910 | for (digits = 0; isdigit ((*argv)[digits]); digits++) |
| 3911 | {; |
| 3912 | } |
| 3913 | allsigs = 0; |
| 3914 | sigfirst = siglast = -1; |
| 3915 | |
| 3916 | if (wordlen >= 1 && !strncmp (*argv, "all", wordlen)) |
| 3917 | { |
| 3918 | /* Apply action to all signals except those used by the |
| 3919 | debugger. Silently skip those. */ |
| 3920 | allsigs = 1; |
| 3921 | sigfirst = 0; |
| 3922 | siglast = nsigs - 1; |
| 3923 | } |
| 3924 | else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen)) |
| 3925 | { |
| 3926 | SET_SIGS (nsigs, sigs, signal_stop); |
| 3927 | SET_SIGS (nsigs, sigs, signal_print); |
| 3928 | } |
| 3929 | else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen)) |
| 3930 | { |
| 3931 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 3932 | } |
| 3933 | else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen)) |
| 3934 | { |
| 3935 | SET_SIGS (nsigs, sigs, signal_print); |
| 3936 | } |
| 3937 | else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen)) |
| 3938 | { |
| 3939 | SET_SIGS (nsigs, sigs, signal_program); |
| 3940 | } |
| 3941 | else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen)) |
| 3942 | { |
| 3943 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 3944 | } |
| 3945 | else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen)) |
| 3946 | { |
| 3947 | SET_SIGS (nsigs, sigs, signal_program); |
| 3948 | } |
| 3949 | else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen)) |
| 3950 | { |
| 3951 | UNSET_SIGS (nsigs, sigs, signal_print); |
| 3952 | UNSET_SIGS (nsigs, sigs, signal_stop); |
| 3953 | } |
| 3954 | else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen)) |
| 3955 | { |
| 3956 | UNSET_SIGS (nsigs, sigs, signal_program); |
| 3957 | } |
| 3958 | else if (digits > 0) |
| 3959 | { |
| 3960 | /* It is numeric. The numeric signal refers to our own |
| 3961 | internal signal numbering from target.h, not to host/target |
| 3962 | signal number. This is a feature; users really should be |
| 3963 | using symbolic names anyway, and the common ones like |
| 3964 | SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */ |
| 3965 | |
| 3966 | sigfirst = siglast = (int) |
| 3967 | target_signal_from_command (atoi (*argv)); |
| 3968 | if ((*argv)[digits] == '-') |
| 3969 | { |
| 3970 | siglast = (int) |
| 3971 | target_signal_from_command (atoi ((*argv) + digits + 1)); |
| 3972 | } |
| 3973 | if (sigfirst > siglast) |
| 3974 | { |
| 3975 | /* Bet he didn't figure we'd think of this case... */ |
| 3976 | signum = sigfirst; |
| 3977 | sigfirst = siglast; |
| 3978 | siglast = signum; |
| 3979 | } |
| 3980 | } |
| 3981 | else |
| 3982 | { |
| 3983 | oursig = target_signal_from_name (*argv); |
| 3984 | if (oursig != TARGET_SIGNAL_UNKNOWN) |
| 3985 | { |
| 3986 | sigfirst = siglast = (int) oursig; |
| 3987 | } |
| 3988 | else |
| 3989 | { |
| 3990 | /* Not a number and not a recognized flag word => complain. */ |
| 3991 | error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv); |
| 3992 | } |
| 3993 | } |
| 3994 | |
| 3995 | /* If any signal numbers or symbol names were found, set flags for |
| 3996 | which signals to apply actions to. */ |
| 3997 | |
| 3998 | for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++) |
| 3999 | { |
| 4000 | switch ((enum target_signal) signum) |
| 4001 | { |
| 4002 | case TARGET_SIGNAL_TRAP: |
| 4003 | case TARGET_SIGNAL_INT: |
| 4004 | if (!allsigs && !sigs[signum]) |
| 4005 | { |
| 4006 | if (query ("%s is used by the debugger.\n\ |
| 4007 | Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum))) |
| 4008 | { |
| 4009 | sigs[signum] = 1; |
| 4010 | } |
| 4011 | else |
| 4012 | { |
| 4013 | printf_unfiltered (_("Not confirmed, unchanged.\n")); |
| 4014 | gdb_flush (gdb_stdout); |
| 4015 | } |
| 4016 | } |
| 4017 | break; |
| 4018 | case TARGET_SIGNAL_0: |
| 4019 | case TARGET_SIGNAL_DEFAULT: |
| 4020 | case TARGET_SIGNAL_UNKNOWN: |
| 4021 | /* Make sure that "all" doesn't print these. */ |
| 4022 | break; |
| 4023 | default: |
| 4024 | sigs[signum] = 1; |
| 4025 | break; |
| 4026 | } |
| 4027 | } |
| 4028 | |
| 4029 | argv++; |
| 4030 | } |
| 4031 | |
| 4032 | target_notice_signals (inferior_ptid); |
| 4033 | |
| 4034 | if (from_tty) |
| 4035 | { |
| 4036 | /* Show the results. */ |
| 4037 | sig_print_header (); |
| 4038 | for (signum = 0; signum < nsigs; signum++) |
| 4039 | { |
| 4040 | if (sigs[signum]) |
| 4041 | { |
| 4042 | sig_print_info (signum); |
| 4043 | } |
| 4044 | } |
| 4045 | } |
| 4046 | |
| 4047 | do_cleanups (old_chain); |
| 4048 | } |
| 4049 | |
| 4050 | static void |
| 4051 | xdb_handle_command (char *args, int from_tty) |
| 4052 | { |
| 4053 | char **argv; |
| 4054 | struct cleanup *old_chain; |
| 4055 | |
| 4056 | /* Break the command line up into args. */ |
| 4057 | |
| 4058 | argv = buildargv (args); |
| 4059 | if (argv == NULL) |
| 4060 | { |
| 4061 | nomem (0); |
| 4062 | } |
| 4063 | old_chain = make_cleanup_freeargv (argv); |
| 4064 | if (argv[1] != (char *) NULL) |
| 4065 | { |
| 4066 | char *argBuf; |
| 4067 | int bufLen; |
| 4068 | |
| 4069 | bufLen = strlen (argv[0]) + 20; |
| 4070 | argBuf = (char *) xmalloc (bufLen); |
| 4071 | if (argBuf) |
| 4072 | { |
| 4073 | int validFlag = 1; |
| 4074 | enum target_signal oursig; |
| 4075 | |
| 4076 | oursig = target_signal_from_name (argv[0]); |
| 4077 | memset (argBuf, 0, bufLen); |
| 4078 | if (strcmp (argv[1], "Q") == 0) |
| 4079 | sprintf (argBuf, "%s %s", argv[0], "noprint"); |
| 4080 | else |
| 4081 | { |
| 4082 | if (strcmp (argv[1], "s") == 0) |
| 4083 | { |
| 4084 | if (!signal_stop[oursig]) |
| 4085 | sprintf (argBuf, "%s %s", argv[0], "stop"); |
| 4086 | else |
| 4087 | sprintf (argBuf, "%s %s", argv[0], "nostop"); |
| 4088 | } |
| 4089 | else if (strcmp (argv[1], "i") == 0) |
| 4090 | { |
| 4091 | if (!signal_program[oursig]) |
| 4092 | sprintf (argBuf, "%s %s", argv[0], "pass"); |
| 4093 | else |
| 4094 | sprintf (argBuf, "%s %s", argv[0], "nopass"); |
| 4095 | } |
| 4096 | else if (strcmp (argv[1], "r") == 0) |
| 4097 | { |
| 4098 | if (!signal_print[oursig]) |
| 4099 | sprintf (argBuf, "%s %s", argv[0], "print"); |
| 4100 | else |
| 4101 | sprintf (argBuf, "%s %s", argv[0], "noprint"); |
| 4102 | } |
| 4103 | else |
| 4104 | validFlag = 0; |
| 4105 | } |
| 4106 | if (validFlag) |
| 4107 | handle_command (argBuf, from_tty); |
| 4108 | else |
| 4109 | printf_filtered (_("Invalid signal handling flag.\n")); |
| 4110 | if (argBuf) |
| 4111 | xfree (argBuf); |
| 4112 | } |
| 4113 | } |
| 4114 | do_cleanups (old_chain); |
| 4115 | } |
| 4116 | |
| 4117 | /* Print current contents of the tables set by the handle command. |
| 4118 | It is possible we should just be printing signals actually used |
| 4119 | by the current target (but for things to work right when switching |
| 4120 | targets, all signals should be in the signal tables). */ |
| 4121 | |
| 4122 | static void |
| 4123 | signals_info (char *signum_exp, int from_tty) |
| 4124 | { |
| 4125 | enum target_signal oursig; |
| 4126 | sig_print_header (); |
| 4127 | |
| 4128 | if (signum_exp) |
| 4129 | { |
| 4130 | /* First see if this is a symbol name. */ |
| 4131 | oursig = target_signal_from_name (signum_exp); |
| 4132 | if (oursig == TARGET_SIGNAL_UNKNOWN) |
| 4133 | { |
| 4134 | /* No, try numeric. */ |
| 4135 | oursig = |
| 4136 | target_signal_from_command (parse_and_eval_long (signum_exp)); |
| 4137 | } |
| 4138 | sig_print_info (oursig); |
| 4139 | return; |
| 4140 | } |
| 4141 | |
| 4142 | printf_filtered ("\n"); |
| 4143 | /* These ugly casts brought to you by the native VAX compiler. */ |
| 4144 | for (oursig = TARGET_SIGNAL_FIRST; |
| 4145 | (int) oursig < (int) TARGET_SIGNAL_LAST; |
| 4146 | oursig = (enum target_signal) ((int) oursig + 1)) |
| 4147 | { |
| 4148 | QUIT; |
| 4149 | |
| 4150 | if (oursig != TARGET_SIGNAL_UNKNOWN |
| 4151 | && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0) |
| 4152 | sig_print_info (oursig); |
| 4153 | } |
| 4154 | |
| 4155 | printf_filtered (_("\nUse the \"handle\" command to change these tables.\n")); |
| 4156 | } |
| 4157 | \f |
| 4158 | struct inferior_status |
| 4159 | { |
| 4160 | enum target_signal stop_signal; |
| 4161 | CORE_ADDR stop_pc; |
| 4162 | bpstat stop_bpstat; |
| 4163 | int stop_step; |
| 4164 | int stop_stack_dummy; |
| 4165 | int stopped_by_random_signal; |
| 4166 | int stepping_over_breakpoint; |
| 4167 | CORE_ADDR step_range_start; |
| 4168 | CORE_ADDR step_range_end; |
| 4169 | struct frame_id step_frame_id; |
| 4170 | enum step_over_calls_kind step_over_calls; |
| 4171 | CORE_ADDR step_resume_break_address; |
| 4172 | int stop_after_trap; |
| 4173 | int stop_soon; |
| 4174 | |
| 4175 | /* These are here because if call_function_by_hand has written some |
| 4176 | registers and then decides to call error(), we better not have changed |
| 4177 | any registers. */ |
| 4178 | struct regcache *registers; |
| 4179 | |
| 4180 | /* A frame unique identifier. */ |
| 4181 | struct frame_id selected_frame_id; |
| 4182 | |
| 4183 | int breakpoint_proceeded; |
| 4184 | int restore_stack_info; |
| 4185 | int proceed_to_finish; |
| 4186 | }; |
| 4187 | |
| 4188 | void |
| 4189 | write_inferior_status_register (struct inferior_status *inf_status, int regno, |
| 4190 | LONGEST val) |
| 4191 | { |
| 4192 | int size = register_size (current_gdbarch, regno); |
| 4193 | void *buf = alloca (size); |
| 4194 | store_signed_integer (buf, size, val); |
| 4195 | regcache_raw_write (inf_status->registers, regno, buf); |
| 4196 | } |
| 4197 | |
| 4198 | /* Save all of the information associated with the inferior<==>gdb |
| 4199 | connection. INF_STATUS is a pointer to a "struct inferior_status" |
| 4200 | (defined in inferior.h). */ |
| 4201 | |
| 4202 | struct inferior_status * |
| 4203 | save_inferior_status (int restore_stack_info) |
| 4204 | { |
| 4205 | struct inferior_status *inf_status = XMALLOC (struct inferior_status); |
| 4206 | |
| 4207 | inf_status->stop_signal = stop_signal; |
| 4208 | inf_status->stop_pc = stop_pc; |
| 4209 | inf_status->stop_step = stop_step; |
| 4210 | inf_status->stop_stack_dummy = stop_stack_dummy; |
| 4211 | inf_status->stopped_by_random_signal = stopped_by_random_signal; |
| 4212 | inf_status->stepping_over_breakpoint = stepping_over_breakpoint; |
| 4213 | inf_status->step_range_start = step_range_start; |
| 4214 | inf_status->step_range_end = step_range_end; |
| 4215 | inf_status->step_frame_id = step_frame_id; |
| 4216 | inf_status->step_over_calls = step_over_calls; |
| 4217 | inf_status->stop_after_trap = stop_after_trap; |
| 4218 | inf_status->stop_soon = stop_soon; |
| 4219 | /* Save original bpstat chain here; replace it with copy of chain. |
| 4220 | If caller's caller is walking the chain, they'll be happier if we |
| 4221 | hand them back the original chain when restore_inferior_status is |
| 4222 | called. */ |
| 4223 | inf_status->stop_bpstat = stop_bpstat; |
| 4224 | stop_bpstat = bpstat_copy (stop_bpstat); |
| 4225 | inf_status->breakpoint_proceeded = breakpoint_proceeded; |
| 4226 | inf_status->restore_stack_info = restore_stack_info; |
| 4227 | inf_status->proceed_to_finish = proceed_to_finish; |
| 4228 | |
| 4229 | inf_status->registers = regcache_dup (get_current_regcache ()); |
| 4230 | |
| 4231 | inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL)); |
| 4232 | return inf_status; |
| 4233 | } |
| 4234 | |
| 4235 | static int |
| 4236 | restore_selected_frame (void *args) |
| 4237 | { |
| 4238 | struct frame_id *fid = (struct frame_id *) args; |
| 4239 | struct frame_info *frame; |
| 4240 | |
| 4241 | frame = frame_find_by_id (*fid); |
| 4242 | |
| 4243 | /* If inf_status->selected_frame_id is NULL, there was no previously |
| 4244 | selected frame. */ |
| 4245 | if (frame == NULL) |
| 4246 | { |
| 4247 | warning (_("Unable to restore previously selected frame.")); |
| 4248 | return 0; |
| 4249 | } |
| 4250 | |
| 4251 | select_frame (frame); |
| 4252 | |
| 4253 | return (1); |
| 4254 | } |
| 4255 | |
| 4256 | void |
| 4257 | restore_inferior_status (struct inferior_status *inf_status) |
| 4258 | { |
| 4259 | stop_signal = inf_status->stop_signal; |
| 4260 | stop_pc = inf_status->stop_pc; |
| 4261 | stop_step = inf_status->stop_step; |
| 4262 | stop_stack_dummy = inf_status->stop_stack_dummy; |
| 4263 | stopped_by_random_signal = inf_status->stopped_by_random_signal; |
| 4264 | stepping_over_breakpoint = inf_status->stepping_over_breakpoint; |
| 4265 | step_range_start = inf_status->step_range_start; |
| 4266 | step_range_end = inf_status->step_range_end; |
| 4267 | step_frame_id = inf_status->step_frame_id; |
| 4268 | step_over_calls = inf_status->step_over_calls; |
| 4269 | stop_after_trap = inf_status->stop_after_trap; |
| 4270 | stop_soon = inf_status->stop_soon; |
| 4271 | bpstat_clear (&stop_bpstat); |
| 4272 | stop_bpstat = inf_status->stop_bpstat; |
| 4273 | breakpoint_proceeded = inf_status->breakpoint_proceeded; |
| 4274 | proceed_to_finish = inf_status->proceed_to_finish; |
| 4275 | |
| 4276 | /* The inferior can be gone if the user types "print exit(0)" |
| 4277 | (and perhaps other times). */ |
| 4278 | if (target_has_execution) |
| 4279 | /* NB: The register write goes through to the target. */ |
| 4280 | regcache_cpy (get_current_regcache (), inf_status->registers); |
| 4281 | regcache_xfree (inf_status->registers); |
| 4282 | |
| 4283 | /* FIXME: If we are being called after stopping in a function which |
| 4284 | is called from gdb, we should not be trying to restore the |
| 4285 | selected frame; it just prints a spurious error message (The |
| 4286 | message is useful, however, in detecting bugs in gdb (like if gdb |
| 4287 | clobbers the stack)). In fact, should we be restoring the |
| 4288 | inferior status at all in that case? . */ |
| 4289 | |
| 4290 | if (target_has_stack && inf_status->restore_stack_info) |
| 4291 | { |
| 4292 | /* The point of catch_errors is that if the stack is clobbered, |
| 4293 | walking the stack might encounter a garbage pointer and |
| 4294 | error() trying to dereference it. */ |
| 4295 | if (catch_errors |
| 4296 | (restore_selected_frame, &inf_status->selected_frame_id, |
| 4297 | "Unable to restore previously selected frame:\n", |
| 4298 | RETURN_MASK_ERROR) == 0) |
| 4299 | /* Error in restoring the selected frame. Select the innermost |
| 4300 | frame. */ |
| 4301 | select_frame (get_current_frame ()); |
| 4302 | |
| 4303 | } |
| 4304 | |
| 4305 | xfree (inf_status); |
| 4306 | } |
| 4307 | |
| 4308 | static void |
| 4309 | do_restore_inferior_status_cleanup (void *sts) |
| 4310 | { |
| 4311 | restore_inferior_status (sts); |
| 4312 | } |
| 4313 | |
| 4314 | struct cleanup * |
| 4315 | make_cleanup_restore_inferior_status (struct inferior_status *inf_status) |
| 4316 | { |
| 4317 | return make_cleanup (do_restore_inferior_status_cleanup, inf_status); |
| 4318 | } |
| 4319 | |
| 4320 | void |
| 4321 | discard_inferior_status (struct inferior_status *inf_status) |
| 4322 | { |
| 4323 | /* See save_inferior_status for info on stop_bpstat. */ |
| 4324 | bpstat_clear (&inf_status->stop_bpstat); |
| 4325 | regcache_xfree (inf_status->registers); |
| 4326 | xfree (inf_status); |
| 4327 | } |
| 4328 | |
| 4329 | int |
| 4330 | inferior_has_forked (ptid_t pid, ptid_t *child_pid) |
| 4331 | { |
| 4332 | struct target_waitstatus last; |
| 4333 | ptid_t last_ptid; |
| 4334 | |
| 4335 | get_last_target_status (&last_ptid, &last); |
| 4336 | |
| 4337 | if (last.kind != TARGET_WAITKIND_FORKED) |
| 4338 | return 0; |
| 4339 | |
| 4340 | if (!ptid_equal (last_ptid, pid)) |
| 4341 | return 0; |
| 4342 | |
| 4343 | *child_pid = last.value.related_pid; |
| 4344 | return 1; |
| 4345 | } |
| 4346 | |
| 4347 | int |
| 4348 | inferior_has_vforked (ptid_t pid, ptid_t *child_pid) |
| 4349 | { |
| 4350 | struct target_waitstatus last; |
| 4351 | ptid_t last_ptid; |
| 4352 | |
| 4353 | get_last_target_status (&last_ptid, &last); |
| 4354 | |
| 4355 | if (last.kind != TARGET_WAITKIND_VFORKED) |
| 4356 | return 0; |
| 4357 | |
| 4358 | if (!ptid_equal (last_ptid, pid)) |
| 4359 | return 0; |
| 4360 | |
| 4361 | *child_pid = last.value.related_pid; |
| 4362 | return 1; |
| 4363 | } |
| 4364 | |
| 4365 | int |
| 4366 | inferior_has_execd (ptid_t pid, char **execd_pathname) |
| 4367 | { |
| 4368 | struct target_waitstatus last; |
| 4369 | ptid_t last_ptid; |
| 4370 | |
| 4371 | get_last_target_status (&last_ptid, &last); |
| 4372 | |
| 4373 | if (last.kind != TARGET_WAITKIND_EXECD) |
| 4374 | return 0; |
| 4375 | |
| 4376 | if (!ptid_equal (last_ptid, pid)) |
| 4377 | return 0; |
| 4378 | |
| 4379 | *execd_pathname = xstrdup (last.value.execd_pathname); |
| 4380 | return 1; |
| 4381 | } |
| 4382 | |
| 4383 | /* Oft used ptids */ |
| 4384 | ptid_t null_ptid; |
| 4385 | ptid_t minus_one_ptid; |
| 4386 | |
| 4387 | /* Create a ptid given the necessary PID, LWP, and TID components. */ |
| 4388 | |
| 4389 | ptid_t |
| 4390 | ptid_build (int pid, long lwp, long tid) |
| 4391 | { |
| 4392 | ptid_t ptid; |
| 4393 | |
| 4394 | ptid.pid = pid; |
| 4395 | ptid.lwp = lwp; |
| 4396 | ptid.tid = tid; |
| 4397 | return ptid; |
| 4398 | } |
| 4399 | |
| 4400 | /* Create a ptid from just a pid. */ |
| 4401 | |
| 4402 | ptid_t |
| 4403 | pid_to_ptid (int pid) |
| 4404 | { |
| 4405 | return ptid_build (pid, 0, 0); |
| 4406 | } |
| 4407 | |
| 4408 | /* Fetch the pid (process id) component from a ptid. */ |
| 4409 | |
| 4410 | int |
| 4411 | ptid_get_pid (ptid_t ptid) |
| 4412 | { |
| 4413 | return ptid.pid; |
| 4414 | } |
| 4415 | |
| 4416 | /* Fetch the lwp (lightweight process) component from a ptid. */ |
| 4417 | |
| 4418 | long |
| 4419 | ptid_get_lwp (ptid_t ptid) |
| 4420 | { |
| 4421 | return ptid.lwp; |
| 4422 | } |
| 4423 | |
| 4424 | /* Fetch the tid (thread id) component from a ptid. */ |
| 4425 | |
| 4426 | long |
| 4427 | ptid_get_tid (ptid_t ptid) |
| 4428 | { |
| 4429 | return ptid.tid; |
| 4430 | } |
| 4431 | |
| 4432 | /* ptid_equal() is used to test equality of two ptids. */ |
| 4433 | |
| 4434 | int |
| 4435 | ptid_equal (ptid_t ptid1, ptid_t ptid2) |
| 4436 | { |
| 4437 | return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp |
| 4438 | && ptid1.tid == ptid2.tid); |
| 4439 | } |
| 4440 | |
| 4441 | /* restore_inferior_ptid() will be used by the cleanup machinery |
| 4442 | to restore the inferior_ptid value saved in a call to |
| 4443 | save_inferior_ptid(). */ |
| 4444 | |
| 4445 | static void |
| 4446 | restore_inferior_ptid (void *arg) |
| 4447 | { |
| 4448 | ptid_t *saved_ptid_ptr = arg; |
| 4449 | inferior_ptid = *saved_ptid_ptr; |
| 4450 | xfree (arg); |
| 4451 | } |
| 4452 | |
| 4453 | /* Save the value of inferior_ptid so that it may be restored by a |
| 4454 | later call to do_cleanups(). Returns the struct cleanup pointer |
| 4455 | needed for later doing the cleanup. */ |
| 4456 | |
| 4457 | struct cleanup * |
| 4458 | save_inferior_ptid (void) |
| 4459 | { |
| 4460 | ptid_t *saved_ptid_ptr; |
| 4461 | |
| 4462 | saved_ptid_ptr = xmalloc (sizeof (ptid_t)); |
| 4463 | *saved_ptid_ptr = inferior_ptid; |
| 4464 | return make_cleanup (restore_inferior_ptid, saved_ptid_ptr); |
| 4465 | } |
| 4466 | \f |
| 4467 | |
| 4468 | void |
| 4469 | _initialize_infrun (void) |
| 4470 | { |
| 4471 | int i; |
| 4472 | int numsigs; |
| 4473 | struct cmd_list_element *c; |
| 4474 | |
| 4475 | add_info ("signals", signals_info, _("\ |
| 4476 | What debugger does when program gets various signals.\n\ |
| 4477 | Specify a signal as argument to print info on that signal only.")); |
| 4478 | add_info_alias ("handle", "signals", 0); |
| 4479 | |
| 4480 | add_com ("handle", class_run, handle_command, _("\ |
| 4481 | Specify how to handle a signal.\n\ |
| 4482 | Args are signals and actions to apply to those signals.\n\ |
| 4483 | Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ |
| 4484 | from 1-15 are allowed for compatibility with old versions of GDB.\n\ |
| 4485 | Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ |
| 4486 | The special arg \"all\" is recognized to mean all signals except those\n\ |
| 4487 | used by the debugger, typically SIGTRAP and SIGINT.\n\ |
| 4488 | Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\ |
| 4489 | \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\ |
| 4490 | Stop means reenter debugger if this signal happens (implies print).\n\ |
| 4491 | Print means print a message if this signal happens.\n\ |
| 4492 | Pass means let program see this signal; otherwise program doesn't know.\n\ |
| 4493 | Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ |
| 4494 | Pass and Stop may be combined.")); |
| 4495 | if (xdb_commands) |
| 4496 | { |
| 4497 | add_com ("lz", class_info, signals_info, _("\ |
| 4498 | What debugger does when program gets various signals.\n\ |
| 4499 | Specify a signal as argument to print info on that signal only.")); |
| 4500 | add_com ("z", class_run, xdb_handle_command, _("\ |
| 4501 | Specify how to handle a signal.\n\ |
| 4502 | Args are signals and actions to apply to those signals.\n\ |
| 4503 | Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\ |
| 4504 | from 1-15 are allowed for compatibility with old versions of GDB.\n\ |
| 4505 | Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\ |
| 4506 | The special arg \"all\" is recognized to mean all signals except those\n\ |
| 4507 | used by the debugger, typically SIGTRAP and SIGINT.\n\ |
| 4508 | Recognized actions include \"s\" (toggles between stop and nostop), \n\ |
| 4509 | \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \ |
| 4510 | nopass), \"Q\" (noprint)\n\ |
| 4511 | Stop means reenter debugger if this signal happens (implies print).\n\ |
| 4512 | Print means print a message if this signal happens.\n\ |
| 4513 | Pass means let program see this signal; otherwise program doesn't know.\n\ |
| 4514 | Ignore is a synonym for nopass and noignore is a synonym for pass.\n\ |
| 4515 | Pass and Stop may be combined.")); |
| 4516 | } |
| 4517 | |
| 4518 | if (!dbx_commands) |
| 4519 | stop_command = add_cmd ("stop", class_obscure, |
| 4520 | not_just_help_class_command, _("\ |
| 4521 | There is no `stop' command, but you can set a hook on `stop'.\n\ |
| 4522 | This allows you to set a list of commands to be run each time execution\n\ |
| 4523 | of the program stops."), &cmdlist); |
| 4524 | |
| 4525 | add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\ |
| 4526 | Set inferior debugging."), _("\ |
| 4527 | Show inferior debugging."), _("\ |
| 4528 | When non-zero, inferior specific debugging is enabled."), |
| 4529 | NULL, |
| 4530 | show_debug_infrun, |
| 4531 | &setdebuglist, &showdebuglist); |
| 4532 | |
| 4533 | add_setshow_boolean_cmd ("displaced", class_maintenance, &debug_displaced, _("\ |
| 4534 | Set displaced stepping debugging."), _("\ |
| 4535 | Show displaced stepping debugging."), _("\ |
| 4536 | When non-zero, displaced stepping specific debugging is enabled."), |
| 4537 | NULL, |
| 4538 | show_debug_displaced, |
| 4539 | &setdebuglist, &showdebuglist); |
| 4540 | |
| 4541 | numsigs = (int) TARGET_SIGNAL_LAST; |
| 4542 | signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs); |
| 4543 | signal_print = (unsigned char *) |
| 4544 | xmalloc (sizeof (signal_print[0]) * numsigs); |
| 4545 | signal_program = (unsigned char *) |
| 4546 | xmalloc (sizeof (signal_program[0]) * numsigs); |
| 4547 | for (i = 0; i < numsigs; i++) |
| 4548 | { |
| 4549 | signal_stop[i] = 1; |
| 4550 | signal_print[i] = 1; |
| 4551 | signal_program[i] = 1; |
| 4552 | } |
| 4553 | |
| 4554 | /* Signals caused by debugger's own actions |
| 4555 | should not be given to the program afterwards. */ |
| 4556 | signal_program[TARGET_SIGNAL_TRAP] = 0; |
| 4557 | signal_program[TARGET_SIGNAL_INT] = 0; |
| 4558 | |
| 4559 | /* Signals that are not errors should not normally enter the debugger. */ |
| 4560 | signal_stop[TARGET_SIGNAL_ALRM] = 0; |
| 4561 | signal_print[TARGET_SIGNAL_ALRM] = 0; |
| 4562 | signal_stop[TARGET_SIGNAL_VTALRM] = 0; |
| 4563 | signal_print[TARGET_SIGNAL_VTALRM] = 0; |
| 4564 | signal_stop[TARGET_SIGNAL_PROF] = 0; |
| 4565 | signal_print[TARGET_SIGNAL_PROF] = 0; |
| 4566 | signal_stop[TARGET_SIGNAL_CHLD] = 0; |
| 4567 | signal_print[TARGET_SIGNAL_CHLD] = 0; |
| 4568 | signal_stop[TARGET_SIGNAL_IO] = 0; |
| 4569 | signal_print[TARGET_SIGNAL_IO] = 0; |
| 4570 | signal_stop[TARGET_SIGNAL_POLL] = 0; |
| 4571 | signal_print[TARGET_SIGNAL_POLL] = 0; |
| 4572 | signal_stop[TARGET_SIGNAL_URG] = 0; |
| 4573 | signal_print[TARGET_SIGNAL_URG] = 0; |
| 4574 | signal_stop[TARGET_SIGNAL_WINCH] = 0; |
| 4575 | signal_print[TARGET_SIGNAL_WINCH] = 0; |
| 4576 | |
| 4577 | /* These signals are used internally by user-level thread |
| 4578 | implementations. (See signal(5) on Solaris.) Like the above |
| 4579 | signals, a healthy program receives and handles them as part of |
| 4580 | its normal operation. */ |
| 4581 | signal_stop[TARGET_SIGNAL_LWP] = 0; |
| 4582 | signal_print[TARGET_SIGNAL_LWP] = 0; |
| 4583 | signal_stop[TARGET_SIGNAL_WAITING] = 0; |
| 4584 | signal_print[TARGET_SIGNAL_WAITING] = 0; |
| 4585 | signal_stop[TARGET_SIGNAL_CANCEL] = 0; |
| 4586 | signal_print[TARGET_SIGNAL_CANCEL] = 0; |
| 4587 | |
| 4588 | add_setshow_zinteger_cmd ("stop-on-solib-events", class_support, |
| 4589 | &stop_on_solib_events, _("\ |
| 4590 | Set stopping for shared library events."), _("\ |
| 4591 | Show stopping for shared library events."), _("\ |
| 4592 | If nonzero, gdb will give control to the user when the dynamic linker\n\ |
| 4593 | notifies gdb of shared library events. The most common event of interest\n\ |
| 4594 | to the user would be loading/unloading of a new library."), |
| 4595 | NULL, |
| 4596 | show_stop_on_solib_events, |
| 4597 | &setlist, &showlist); |
| 4598 | |
| 4599 | add_setshow_enum_cmd ("follow-fork-mode", class_run, |
| 4600 | follow_fork_mode_kind_names, |
| 4601 | &follow_fork_mode_string, _("\ |
| 4602 | Set debugger response to a program call of fork or vfork."), _("\ |
| 4603 | Show debugger response to a program call of fork or vfork."), _("\ |
| 4604 | A fork or vfork creates a new process. follow-fork-mode can be:\n\ |
| 4605 | parent - the original process is debugged after a fork\n\ |
| 4606 | child - the new process is debugged after a fork\n\ |
| 4607 | The unfollowed process will continue to run.\n\ |
| 4608 | By default, the debugger will follow the parent process."), |
| 4609 | NULL, |
| 4610 | show_follow_fork_mode_string, |
| 4611 | &setlist, &showlist); |
| 4612 | |
| 4613 | add_setshow_enum_cmd ("scheduler-locking", class_run, |
| 4614 | scheduler_enums, &scheduler_mode, _("\ |
| 4615 | Set mode for locking scheduler during execution."), _("\ |
| 4616 | Show mode for locking scheduler during execution."), _("\ |
| 4617 | off == no locking (threads may preempt at any time)\n\ |
| 4618 | on == full locking (no thread except the current thread may run)\n\ |
| 4619 | step == scheduler locked during every single-step operation.\n\ |
| 4620 | In this mode, no other thread may run during a step command.\n\ |
| 4621 | Other threads may run while stepping over a function call ('next')."), |
| 4622 | set_schedlock_func, /* traps on target vector */ |
| 4623 | show_scheduler_mode, |
| 4624 | &setlist, &showlist); |
| 4625 | |
| 4626 | add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\ |
| 4627 | Set mode of the step operation."), _("\ |
| 4628 | Show mode of the step operation."), _("\ |
| 4629 | When set, doing a step over a function without debug line information\n\ |
| 4630 | will stop at the first instruction of that function. Otherwise, the\n\ |
| 4631 | function is skipped and the step command stops at a different source line."), |
| 4632 | NULL, |
| 4633 | show_step_stop_if_no_debug, |
| 4634 | &setlist, &showlist); |
| 4635 | |
| 4636 | add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance, |
| 4637 | &can_use_displaced_stepping, _("\ |
| 4638 | Set debugger's willingness to use displaced stepping."), _("\ |
| 4639 | Show debugger's willingness to use displaced stepping."), _("\ |
| 4640 | If zero, gdb will not use displaced stepping to step over\n\ |
| 4641 | breakpoints, even if such is supported by the target."), |
| 4642 | NULL, |
| 4643 | show_can_use_displaced_stepping, |
| 4644 | &maintenance_set_cmdlist, |
| 4645 | &maintenance_show_cmdlist); |
| 4646 | |
| 4647 | /* ptid initializations */ |
| 4648 | null_ptid = ptid_build (0, 0, 0); |
| 4649 | minus_one_ptid = ptid_build (-1, 0, 0); |
| 4650 | inferior_ptid = null_ptid; |
| 4651 | target_last_wait_ptid = minus_one_ptid; |
| 4652 | displaced_step_ptid = null_ptid; |
| 4653 | } |