| 1 | /* Target operations for the remote server for GDB. |
| 2 | Copyright (C) 2002-2018 Free Software Foundation, Inc. |
| 3 | |
| 4 | Contributed by MontaVista Software. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "server.h" |
| 22 | #include "tracepoint.h" |
| 23 | |
| 24 | struct target_ops *the_target; |
| 25 | |
| 26 | int |
| 27 | set_desired_thread () |
| 28 | { |
| 29 | client_state &cs = get_client_state (); |
| 30 | thread_info *found = find_thread_ptid (cs.general_thread); |
| 31 | |
| 32 | current_thread = found; |
| 33 | return (current_thread != NULL); |
| 34 | } |
| 35 | |
| 36 | /* The thread that was current before prepare_to_access_memory was |
| 37 | called. done_accessing_memory uses this to restore the previous |
| 38 | selected thread. */ |
| 39 | static ptid_t prev_general_thread; |
| 40 | |
| 41 | /* See target.h. */ |
| 42 | |
| 43 | int |
| 44 | prepare_to_access_memory (void) |
| 45 | { |
| 46 | client_state &cs = get_client_state (); |
| 47 | |
| 48 | /* The first thread found. */ |
| 49 | struct thread_info *first = NULL; |
| 50 | /* The first stopped thread found. */ |
| 51 | struct thread_info *stopped = NULL; |
| 52 | /* The current general thread, if found. */ |
| 53 | struct thread_info *current = NULL; |
| 54 | |
| 55 | /* Save the general thread value, since prepare_to_access_memory could change |
| 56 | it. */ |
| 57 | prev_general_thread = cs.general_thread; |
| 58 | |
| 59 | if (the_target->prepare_to_access_memory != NULL) |
| 60 | { |
| 61 | int res; |
| 62 | |
| 63 | res = the_target->prepare_to_access_memory (); |
| 64 | if (res != 0) |
| 65 | return res; |
| 66 | } |
| 67 | |
| 68 | for_each_thread (prev_general_thread.pid (), [&] (thread_info *thread) |
| 69 | { |
| 70 | if (mythread_alive (thread->id)) |
| 71 | { |
| 72 | if (stopped == NULL && the_target->thread_stopped != NULL |
| 73 | && thread_stopped (thread)) |
| 74 | stopped = thread; |
| 75 | |
| 76 | if (first == NULL) |
| 77 | first = thread; |
| 78 | |
| 79 | if (current == NULL && prev_general_thread == thread->id) |
| 80 | current = thread; |
| 81 | } |
| 82 | }); |
| 83 | |
| 84 | /* The thread we end up choosing. */ |
| 85 | struct thread_info *thread; |
| 86 | |
| 87 | /* Prefer a stopped thread. If none is found, try the current |
| 88 | thread. Otherwise, take the first thread in the process. If |
| 89 | none is found, undo the effects of |
| 90 | target->prepare_to_access_memory() and return error. */ |
| 91 | if (stopped != NULL) |
| 92 | thread = stopped; |
| 93 | else if (current != NULL) |
| 94 | thread = current; |
| 95 | else if (first != NULL) |
| 96 | thread = first; |
| 97 | else |
| 98 | { |
| 99 | done_accessing_memory (); |
| 100 | return 1; |
| 101 | } |
| 102 | |
| 103 | current_thread = thread; |
| 104 | cs.general_thread = ptid_of (thread); |
| 105 | |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | /* See target.h. */ |
| 110 | |
| 111 | void |
| 112 | done_accessing_memory (void) |
| 113 | { |
| 114 | client_state &cs = get_client_state (); |
| 115 | |
| 116 | if (the_target->done_accessing_memory != NULL) |
| 117 | the_target->done_accessing_memory (); |
| 118 | |
| 119 | /* Restore the previous selected thread. */ |
| 120 | cs.general_thread = prev_general_thread; |
| 121 | switch_to_thread (cs.general_thread); |
| 122 | } |
| 123 | |
| 124 | int |
| 125 | read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len) |
| 126 | { |
| 127 | int res; |
| 128 | res = (*the_target->read_memory) (memaddr, myaddr, len); |
| 129 | check_mem_read (memaddr, myaddr, len); |
| 130 | return res; |
| 131 | } |
| 132 | |
| 133 | /* See target/target.h. */ |
| 134 | |
| 135 | int |
| 136 | target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 137 | { |
| 138 | return read_inferior_memory (memaddr, myaddr, len); |
| 139 | } |
| 140 | |
| 141 | /* See target/target.h. */ |
| 142 | |
| 143 | int |
| 144 | target_read_uint32 (CORE_ADDR memaddr, uint32_t *result) |
| 145 | { |
| 146 | return read_inferior_memory (memaddr, (gdb_byte *) result, sizeof (*result)); |
| 147 | } |
| 148 | |
| 149 | int |
| 150 | write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr, |
| 151 | int len) |
| 152 | { |
| 153 | /* Lacking cleanups, there is some potential for a memory leak if the |
| 154 | write fails and we go through error(). Make sure that no more than |
| 155 | one buffer is ever pending by making BUFFER static. */ |
| 156 | static unsigned char *buffer = 0; |
| 157 | int res; |
| 158 | |
| 159 | if (buffer != NULL) |
| 160 | free (buffer); |
| 161 | |
| 162 | buffer = (unsigned char *) xmalloc (len); |
| 163 | memcpy (buffer, myaddr, len); |
| 164 | check_mem_write (memaddr, buffer, myaddr, len); |
| 165 | res = (*the_target->write_memory) (memaddr, buffer, len); |
| 166 | free (buffer); |
| 167 | buffer = NULL; |
| 168 | |
| 169 | return res; |
| 170 | } |
| 171 | |
| 172 | /* See target/target.h. */ |
| 173 | |
| 174 | int |
| 175 | target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr, ssize_t len) |
| 176 | { |
| 177 | return write_inferior_memory (memaddr, myaddr, len); |
| 178 | } |
| 179 | |
| 180 | ptid_t |
| 181 | mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options, |
| 182 | int connected_wait) |
| 183 | { |
| 184 | ptid_t ret; |
| 185 | |
| 186 | if (connected_wait) |
| 187 | server_waiting = 1; |
| 188 | |
| 189 | ret = target_wait (ptid, ourstatus, options); |
| 190 | |
| 191 | /* We don't expose _LOADED events to gdbserver core. See the |
| 192 | `dlls_changed' global. */ |
| 193 | if (ourstatus->kind == TARGET_WAITKIND_LOADED) |
| 194 | ourstatus->kind = TARGET_WAITKIND_STOPPED; |
| 195 | |
| 196 | /* If GDB is connected through TCP/serial, then GDBserver will most |
| 197 | probably be running on its own terminal/console, so it's nice to |
| 198 | print there why is GDBserver exiting. If however, GDB is |
| 199 | connected through stdio, then there's no need to spam the GDB |
| 200 | console with this -- the user will already see the exit through |
| 201 | regular GDB output, in that same terminal. */ |
| 202 | if (!remote_connection_is_stdio ()) |
| 203 | { |
| 204 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
| 205 | fprintf (stderr, |
| 206 | "\nChild exited with status %d\n", ourstatus->value.integer); |
| 207 | else if (ourstatus->kind == TARGET_WAITKIND_SIGNALLED) |
| 208 | fprintf (stderr, "\nChild terminated with signal = 0x%x (%s)\n", |
| 209 | gdb_signal_to_host (ourstatus->value.sig), |
| 210 | gdb_signal_to_name (ourstatus->value.sig)); |
| 211 | } |
| 212 | |
| 213 | if (connected_wait) |
| 214 | server_waiting = 0; |
| 215 | |
| 216 | return ret; |
| 217 | } |
| 218 | |
| 219 | /* See target/target.h. */ |
| 220 | |
| 221 | void |
| 222 | target_stop_and_wait (ptid_t ptid) |
| 223 | { |
| 224 | struct target_waitstatus status; |
| 225 | int was_non_stop = non_stop; |
| 226 | struct thread_resume resume_info; |
| 227 | |
| 228 | resume_info.thread = ptid; |
| 229 | resume_info.kind = resume_stop; |
| 230 | resume_info.sig = GDB_SIGNAL_0; |
| 231 | (*the_target->resume) (&resume_info, 1); |
| 232 | |
| 233 | non_stop = 1; |
| 234 | mywait (ptid, &status, 0, 0); |
| 235 | non_stop = was_non_stop; |
| 236 | } |
| 237 | |
| 238 | /* See target/target.h. */ |
| 239 | |
| 240 | ptid_t |
| 241 | target_wait (ptid_t ptid, struct target_waitstatus *status, int options) |
| 242 | { |
| 243 | return (*the_target->wait) (ptid, status, options); |
| 244 | } |
| 245 | |
| 246 | /* See target/target.h. */ |
| 247 | |
| 248 | void |
| 249 | target_mourn_inferior (ptid_t ptid) |
| 250 | { |
| 251 | (*the_target->mourn) (find_process_pid (ptid.pid ())); |
| 252 | } |
| 253 | |
| 254 | /* See target/target.h. */ |
| 255 | |
| 256 | void |
| 257 | target_continue_no_signal (ptid_t ptid) |
| 258 | { |
| 259 | struct thread_resume resume_info; |
| 260 | |
| 261 | resume_info.thread = ptid; |
| 262 | resume_info.kind = resume_continue; |
| 263 | resume_info.sig = GDB_SIGNAL_0; |
| 264 | (*the_target->resume) (&resume_info, 1); |
| 265 | } |
| 266 | |
| 267 | /* See target/target.h. */ |
| 268 | |
| 269 | void |
| 270 | target_continue (ptid_t ptid, enum gdb_signal signal) |
| 271 | { |
| 272 | struct thread_resume resume_info; |
| 273 | |
| 274 | resume_info.thread = ptid; |
| 275 | resume_info.kind = resume_continue; |
| 276 | resume_info.sig = gdb_signal_to_host (signal); |
| 277 | (*the_target->resume) (&resume_info, 1); |
| 278 | } |
| 279 | |
| 280 | /* See target/target.h. */ |
| 281 | |
| 282 | int |
| 283 | target_supports_multi_process (void) |
| 284 | { |
| 285 | return (the_target->supports_multi_process != NULL ? |
| 286 | (*the_target->supports_multi_process) () : 0); |
| 287 | } |
| 288 | |
| 289 | int |
| 290 | start_non_stop (int nonstop) |
| 291 | { |
| 292 | if (the_target->start_non_stop == NULL) |
| 293 | { |
| 294 | if (nonstop) |
| 295 | return -1; |
| 296 | else |
| 297 | return 0; |
| 298 | } |
| 299 | |
| 300 | return (*the_target->start_non_stop) (nonstop); |
| 301 | } |
| 302 | |
| 303 | void |
| 304 | set_target_ops (struct target_ops *target) |
| 305 | { |
| 306 | the_target = XNEW (struct target_ops); |
| 307 | memcpy (the_target, target, sizeof (*the_target)); |
| 308 | } |
| 309 | |
| 310 | /* Convert pid to printable format. */ |
| 311 | |
| 312 | const char * |
| 313 | target_pid_to_str (ptid_t ptid) |
| 314 | { |
| 315 | static char buf[80]; |
| 316 | |
| 317 | if (ptid_equal (ptid, minus_one_ptid)) |
| 318 | xsnprintf (buf, sizeof (buf), "<all threads>"); |
| 319 | else if (ptid_equal (ptid, null_ptid)) |
| 320 | xsnprintf (buf, sizeof (buf), "<null thread>"); |
| 321 | else if (ptid.tid () != 0) |
| 322 | xsnprintf (buf, sizeof (buf), "Thread %d.0x%lx", |
| 323 | ptid.pid (), ptid.tid ()); |
| 324 | else if (ptid.lwp () != 0) |
| 325 | xsnprintf (buf, sizeof (buf), "LWP %d.%ld", |
| 326 | ptid.pid (), ptid.lwp ()); |
| 327 | else |
| 328 | xsnprintf (buf, sizeof (buf), "Process %d", |
| 329 | ptid.pid ()); |
| 330 | |
| 331 | return buf; |
| 332 | } |
| 333 | |
| 334 | int |
| 335 | kill_inferior (int pid) |
| 336 | { |
| 337 | gdb_agent_about_to_close (pid); |
| 338 | |
| 339 | return (*the_target->kill) (pid); |
| 340 | } |
| 341 | |
| 342 | /* Target can do hardware single step. */ |
| 343 | |
| 344 | int |
| 345 | target_can_do_hardware_single_step (void) |
| 346 | { |
| 347 | return 1; |
| 348 | } |
| 349 | |
| 350 | /* Default implementation for breakpoint_kind_for_pc. |
| 351 | |
| 352 | The default behavior for targets that don't implement breakpoint_kind_for_pc |
| 353 | is to use the size of a breakpoint as the kind. */ |
| 354 | |
| 355 | int |
| 356 | default_breakpoint_kind_from_pc (CORE_ADDR *pcptr) |
| 357 | { |
| 358 | int size = 0; |
| 359 | |
| 360 | gdb_assert (the_target->sw_breakpoint_from_kind != NULL); |
| 361 | |
| 362 | (*the_target->sw_breakpoint_from_kind) (0, &size); |
| 363 | return size; |
| 364 | } |
| 365 | |
| 366 | /* Define it. */ |
| 367 | |
| 368 | target_terminal_state target_terminal::m_terminal_state |
| 369 | = target_terminal_state::is_ours; |
| 370 | |
| 371 | /* See target/target.h. */ |
| 372 | |
| 373 | void |
| 374 | target_terminal::init () |
| 375 | { |
| 376 | /* Placeholder needed because of fork_inferior. Not necessary on |
| 377 | GDBserver. */ |
| 378 | } |
| 379 | |
| 380 | /* See target/target.h. */ |
| 381 | |
| 382 | void |
| 383 | target_terminal::inferior () |
| 384 | { |
| 385 | /* Placeholder needed because of fork_inferior. Not necessary on |
| 386 | GDBserver. */ |
| 387 | } |
| 388 | |
| 389 | /* See target/target.h. */ |
| 390 | |
| 391 | void |
| 392 | target_terminal::ours () |
| 393 | { |
| 394 | /* Placeholder needed because of fork_inferior. Not necessary on |
| 395 | GDBserver. */ |
| 396 | } |
| 397 | |
| 398 | /* See target/target.h. */ |
| 399 | |
| 400 | void |
| 401 | target_terminal::ours_for_output (void) |
| 402 | { |
| 403 | /* Placeholder. */ |
| 404 | } |
| 405 | |
| 406 | /* See target/target.h. */ |
| 407 | |
| 408 | void |
| 409 | target_terminal::info (const char *arg, int from_tty) |
| 410 | { |
| 411 | /* Placeholder. */ |
| 412 | } |