gdb/inferior.h

   1 /* Variables that describe the inferior process running under GDB:
   2    Where it is, why it stopped, and how to step it.
   3
   4    Copyright (C) 1986-2017 Free Software Foundation, Inc.
   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 #if !defined (INFERIOR_H)
  22 #define INFERIOR_H 1
  23
  24 struct target_waitstatus;
  25 struct frame_info;
  26 struct ui_file;
  27 struct type;
  28 struct gdbarch;
  29 struct regcache;
  30 struct ui_out;
  31 struct terminal_info;
  32 struct target_desc_info;
  33 struct gdb_environ;
  34 struct continuation;
  35
  36 /* For bpstat.  */
  37 #include "breakpoint.h"
  38
  39 /* For enum gdb_signal.  */
  40 #include "target.h"
  41
  42 /* For struct frame_id.  */
  43 #include "frame.h"
  44
  45 #include "progspace.h"
  46 #include "registry.h"
  47
  48 #include "symfile-add-flags.h"
  49
  50 struct infcall_suspend_state;
  51 struct infcall_control_state;
  52
  53 extern struct infcall_suspend_state *save_infcall_suspend_state (void);
  54 extern struct infcall_control_state *save_infcall_control_state (void);
  55
  56 extern void restore_infcall_suspend_state (struct infcall_suspend_state *);
  57 extern void restore_infcall_control_state (struct infcall_control_state *);
  58
  59 extern struct cleanup *make_cleanup_restore_infcall_suspend_state
  60                                             (struct infcall_suspend_state *);
  61 extern struct cleanup *make_cleanup_restore_infcall_control_state
  62                                             (struct infcall_control_state *);
  63
  64 extern void discard_infcall_suspend_state (struct infcall_suspend_state *);
  65 extern void discard_infcall_control_state (struct infcall_control_state *);
  66
  67 extern struct regcache *
  68   get_infcall_suspend_state_regcache (struct infcall_suspend_state *);
  69
  70 /* Save value of inferior_ptid so that it may be restored by
  71    a later call to do_cleanups().  Returns the struct cleanup
  72    pointer needed for later doing the cleanup.  */
  73 extern struct cleanup * save_inferior_ptid (void);
  74
  75 extern void set_sigint_trap (void);
  76
  77 extern void clear_sigint_trap (void);
  78
  79 /* Set/get file name for default use for standard in/out in the inferior.  */
  80
  81 extern void set_inferior_io_terminal (const char *terminal_name);
  82 extern const char *get_inferior_io_terminal (void);
  83
  84 /* Collected pid, tid, etc. of the debugged inferior.  When there's
  85    no inferior, ptid_get_pid (inferior_ptid) will be 0.  */
  86
  87 extern ptid_t inferior_ptid;
  88
  89 extern void generic_mourn_inferior (void);
  90
  91 extern CORE_ADDR unsigned_pointer_to_address (struct gdbarch *gdbarch,
  92                                               struct type *type,
  93                                               const gdb_byte *buf);
  94 extern void unsigned_address_to_pointer (struct gdbarch *gdbarch,
  95                                          struct type *type, gdb_byte *buf,
  96                                          CORE_ADDR addr);
  97 extern CORE_ADDR signed_pointer_to_address (struct gdbarch *gdbarch,
  98                                             struct type *type,
  99                                             const gdb_byte *buf);
 100 extern void address_to_signed_pointer (struct gdbarch *gdbarch,
 101                                        struct type *type, gdb_byte *buf,
 102                                        CORE_ADDR addr);
 103
 104 extern void reopen_exec_file (void);
 105
 106 /* From misc files */
 107
 108 extern void default_print_registers_info (struct gdbarch *gdbarch,
 109                                           struct ui_file *file,
 110                                           struct frame_info *frame,
 111                                           int regnum, int all);
 112
 113 /* Default implementation of gdbarch_print_float_info.  Print
 114    the values of all floating point registers.  */
 115
 116 extern void default_print_float_info (struct gdbarch *gdbarch,
 117                                       struct ui_file *file,
 118                                       struct frame_info *frame,
 119                                       const char *args);
 120
 121 extern void child_terminal_info (struct target_ops *self, const char *, int);
 122
 123 extern void term_info (char *, int);
 124
 125 extern void child_terminal_ours (struct target_ops *self);
 126
 127 extern void child_terminal_ours_for_output (struct target_ops *self);
 128
 129 extern void child_terminal_inferior (struct target_ops *self);
 130
 131 extern void child_terminal_init (struct target_ops *self);
 132
 133 extern void child_terminal_init_with_pgrp (int pgrp);
 134
 135 /* From fork-child.c */
 136
 137 /* Report an error that happened when starting to trace the inferior
 138    (i.e., when the "traceme_fun" callback is called on fork_inferior)
 139    and bail out.  This function does not return.  */
 140
 141 extern void trace_start_error (const char *fmt, ...)
 142   ATTRIBUTE_NORETURN;
 143
 144 /* Like "trace_start_error", but the error message is constructed by
 145    combining STRING with the system error message for errno.  This
 146    function does not return.  */
 147
 148 extern void trace_start_error_with_name (const char *string)
 149   ATTRIBUTE_NORETURN;
 150
 151 extern int fork_inferior (const char *, const std::string &, char **,
 152                           void (*)(void),
 153                           void (*)(int), void (*)(void), char *,
 154                           void (*)(const char *,
 155                                    char * const *, char * const *));
 156
 157
 158 extern void startup_inferior (int);
 159
 160 extern char *construct_inferior_arguments (int, char **);
 161
 162 /* From infcmd.c */
 163
 164 /* Initial inferior setup.  Determines the exec file is not yet known,
 165    takes any necessary post-attaching actions, fetches the target
 166    description and syncs the shared library list.  */
 167
 168 extern void setup_inferior (int from_tty);
 169
 170 extern void post_create_inferior (struct target_ops *, int);
 171
 172 extern void attach_command (char *, int);
 173
 174 extern char *get_inferior_args (void);
 175
 176 extern void set_inferior_args (char *);
 177
 178 extern void set_inferior_args_vector (int, char **);
 179
 180 extern void registers_info (char *, int);
 181
 182 extern void continue_1 (int all_threads);
 183
 184 extern void interrupt_target_1 (int all_threads);
 185
 186 extern void delete_longjmp_breakpoint_cleanup (void *arg);
 187
 188 extern void detach_command (char *, int);
 189
 190 extern void notice_new_inferior (ptid_t, int, int);
 191
 192 extern struct value *get_return_value (struct value *function,
 193                                        struct type *value_type);
 194
 195 /* Prepare for execution command.  TARGET is the target that will run
 196    the command.  BACKGROUND determines whether this is a foreground
 197    (synchronous) or background (asynchronous) command.  */
 198
 199 extern void prepare_execution_command (struct target_ops *target,
 200                                        int background);
 201
 202 /* Whether to start up the debuggee under a shell.
 203
 204    If startup-with-shell is set, GDB's "run" will attempt to start up
 205    the debuggee under a shell.
 206
 207    This is in order for argument-expansion to occur.  E.g.,
 208
 209    (gdb) run *
 210
 211    The "*" gets expanded by the shell into a list of files.
 212
 213    While this is a nice feature, it may be handy to bypass the shell
 214    in some cases.  To disable this feature, do "set startup-with-shell
 215    false".
 216
 217    The catch-exec traps expected during start-up will be one more if
 218    the target is started up with a shell.  */
 219 extern int startup_with_shell;
 220
 221 /* Address at which inferior stopped.  */
 222
 223 extern CORE_ADDR stop_pc;
 224
 225 /* Nonzero if stopped due to completion of a stack dummy routine.  */
 226
 227 extern enum stop_stack_kind stop_stack_dummy;
 228
 229 /* Nonzero if program stopped due to a random (unexpected) signal in
 230    inferior process.  */
 231
 232 extern int stopped_by_random_signal;
 233
 234 /* STEP_OVER_ALL means step over all subroutine calls.
 235    STEP_OVER_UNDEBUGGABLE means step over calls to undebuggable functions.
 236    STEP_OVER_NONE means don't step over any subroutine calls.  */
 237
 238 enum step_over_calls_kind
 239   {
 240     STEP_OVER_NONE,
 241     STEP_OVER_ALL,
 242     STEP_OVER_UNDEBUGGABLE
 243   };
 244
 245 /* Anything but NO_STOP_QUIETLY means we expect a trap and the caller
 246    will handle it themselves.  STOP_QUIETLY is used when running in
 247    the shell before the child program has been exec'd and when running
 248    through shared library loading.  STOP_QUIETLY_REMOTE is used when
 249    setting up a remote connection; it is like STOP_QUIETLY_NO_SIGSTOP
 250    except that there is no need to hide a signal.  */
 251
 252 /* STOP_QUIETLY_NO_SIGSTOP is used to handle a tricky situation with attach.
 253    When doing an attach, the kernel stops the debuggee with a SIGSTOP.
 254    On newer GNU/Linux kernels (>= 2.5.61) the handling of SIGSTOP for
 255    a ptraced process has changed.  Earlier versions of the kernel
 256    would ignore these SIGSTOPs, while now SIGSTOP is treated like any
 257    other signal, i.e. it is not muffled.
 258
 259    If the gdb user does a 'continue' after the 'attach', gdb passes
 260    the global variable stop_signal (which stores the signal from the
 261    attach, SIGSTOP) to the ptrace(PTRACE_CONT,...)  call.  This is
 262    problematic, because the kernel doesn't ignore such SIGSTOP
 263    now.  I.e. it is reported back to gdb, which in turn presents it
 264    back to the user.
 265
 266    To avoid the problem, we use STOP_QUIETLY_NO_SIGSTOP, which allows
 267    gdb to clear the value of stop_signal after the attach, so that it
 268    is not passed back down to the kernel.  */
 269
 270 enum stop_kind
 271   {
 272     NO_STOP_QUIETLY = 0,
 273     STOP_QUIETLY,
 274     STOP_QUIETLY_REMOTE,
 275     STOP_QUIETLY_NO_SIGSTOP
 276   };
 277
 278 \f
 279 /* Possible values for gdbarch_call_dummy_location.  */
 280 #define ON_STACK 1
 281 #define AT_ENTRY_POINT 4
 282
 283 /* Number of traps that happen between exec'ing the shell to run an
 284    inferior and when we finally get to the inferior code, not counting
 285    the exec for the shell.  This is 1 on all supported
 286    implementations.  */
 287 #define START_INFERIOR_TRAPS_EXPECTED   1
 288
 289 struct private_inferior;
 290
 291 /* Inferior process specific part of `struct infcall_control_state'.
 292
 293    Inferior thread counterpart is `struct thread_control_state'.  */
 294
 295 struct inferior_control_state
 296 {
 297   /* See the definition of stop_kind above.  */
 298   enum stop_kind stop_soon;
 299 };
 300
 301 /* GDB represents the state of each program execution with an object
 302    called an inferior.  An inferior typically corresponds to a process
 303    but is more general and applies also to targets that do not have a
 304    notion of processes.  Each run of an executable creates a new
 305    inferior, as does each attachment to an existing process.
 306    Inferiors have unique internal identifiers that are different from
 307    target process ids.  Each inferior may in turn have multiple
 308    threads running in it.  */
 309
 310 class inferior
 311 {
 312 public:
 313   explicit inferior (int pid);
 314   ~inferior ();
 315
 316   /* Pointer to next inferior in singly-linked list of inferiors.  */
 317   struct inferior *next = NULL;
 318
 319   /* Convenient handle (GDB inferior id).  Unique across all
 320      inferiors.  */
 321   int num = 0;
 322
 323   /* Actual target inferior id, usually, a process id.  This matches
 324      the ptid_t.pid member of threads of this inferior.  */
 325   int pid = 0;
 326   /* True if the PID was actually faked by GDB.  */
 327   bool fake_pid_p = false;
 328
 329   /* The highest thread number this inferior ever had.  */
 330   int highest_thread_num = 0;
 331
 332   /* State of GDB control of inferior process execution.
 333      See `struct inferior_control_state'.  */
 334   inferior_control_state control {NO_STOP_QUIETLY};
 335
 336   /* True if this was an auto-created inferior, e.g. created from
 337      following a fork; false, if this inferior was manually added by
 338      the user, and we should not attempt to prune it
 339      automatically.  */
 340   bool removable = false;
 341
 342   /* The address space bound to this inferior.  */
 343   struct address_space *aspace = NULL;
 344
 345   /* The program space bound to this inferior.  */
 346   struct program_space *pspace = NULL;
 347
 348   /* The arguments string to use when running.  */
 349   char *args = NULL;
 350
 351   /* The size of elements in argv.  */
 352   int argc = 0;
 353
 354   /* The vector version of arguments.  If ARGC is nonzero,
 355      then we must compute ARGS from this (via the target).
 356      This is always coming from main's argv and therefore
 357      should never be freed.  */
 358   char **argv = NULL;
 359
 360   /* The name of terminal device to use for I/O.  */
 361   char *terminal = NULL;
 362
 363   /* Environment to use for running inferior,
 364      in format described in environ.h.  */
 365   gdb_environ *environment = NULL;
 366
 367   /* True if this child process was attached rather than forked.  */
 368   bool attach_flag = false;
 369
 370   /* If this inferior is a vfork child, then this is the pointer to
 371      its vfork parent, if GDB is still attached to it.  */
 372   inferior *vfork_parent = NULL;
 373
 374   /* If this process is a vfork parent, this is the pointer to the
 375      child.  Since a vfork parent is left frozen by the kernel until
 376      the child execs or exits, a process can only have one vfork child
 377      at a given time.  */
 378   inferior *vfork_child = NULL;
 379
 380   /* True if this inferior should be detached when it's vfork sibling
 381      exits or execs.  */
 382   bool pending_detach = false;
 383
 384   /* True if this inferior is a vfork parent waiting for a vfork child
 385      not under our control to be done with the shared memory region,
 386      either by exiting or execing.  */
 387   bool waiting_for_vfork_done = false;
 388
 389   /* True if we're in the process of detaching from this inferior.  */
 390   bool detaching = false;
 391
 392   /* What is left to do for an execution command after any thread of
 393      this inferior stops.  For continuations associated with a
 394      specific thread, see `struct thread_info'.  */
 395   continuation *continuations = NULL;
 396
 397   /* True if setup_inferior wasn't called for this inferior yet.
 398      Until that is done, we must not access inferior memory or
 399      registers, as we haven't determined the target
 400      architecture/description.  */
 401   bool needs_setup = false;
 402
 403   /* Private data used by the target vector implementation.  */
 404   private_inferior *priv = NULL;
 405
 406   /* HAS_EXIT_CODE is true if the inferior exited with an exit code.
 407      In this case, the EXIT_CODE field is also valid.  */
 408   bool has_exit_code = false;
 409   LONGEST exit_code = 0;
 410
 411   /* Default flags to pass to the symbol reading functions.  These are
 412      used whenever a new objfile is created.  */
 413   symfile_add_flags symfile_flags = 0;
 414
 415   /* Info about an inferior's target description (if it's fetched; the
 416      user supplied description's filename, if any; etc.).  */
 417   target_desc_info *tdesc_info = NULL;
 418
 419   /* The architecture associated with the inferior through the
 420      connection to the target.
 421
 422      The architecture vector provides some information that is really
 423      a property of the inferior, accessed through a particular target:
 424      ptrace operations; the layout of certain RSP packets; the
 425      solib_ops vector; etc.  To differentiate architecture accesses to
 426      per-inferior/target properties from
 427      per-thread/per-frame/per-objfile properties, accesses to
 428      per-inferior/target properties should be made through
 429      this gdbarch.  */
 430   struct gdbarch *gdbarch = NULL;
 431
 432   /* Per inferior data-pointers required by other GDB modules.  */
 433   REGISTRY_FIELDS;
 434 };
 435
 436 /* Keep a registry of per-inferior data-pointers required by other GDB
 437    modules.  */
 438
 439 DECLARE_REGISTRY (inferior);
 440
 441 /* Add an inferior to the inferior list, print a message that a new
 442    inferior is found, and return the pointer to the new inferior.
 443    Caller may use this pointer to initialize the private inferior
 444    data.  */
 445 extern struct inferior *add_inferior (int pid);
 446
 447 /* Same as add_inferior, but don't print new inferior notifications to
 448    the CLI.  */
 449 extern struct inferior *add_inferior_silent (int pid);
 450
 451 extern void delete_inferior (struct inferior *todel);
 452
 453 /* Delete an existing inferior list entry, due to inferior detaching.  */
 454 extern void detach_inferior (int pid);
 455
 456 extern void exit_inferior (int pid);
 457
 458 extern void exit_inferior_silent (int pid);
 459
 460 extern void exit_inferior_num_silent (int num);
 461
 462 extern void inferior_appeared (struct inferior *inf, int pid);
 463
 464 /* Get rid of all inferiors.  */
 465 extern void discard_all_inferiors (void);
 466
 467 /* Translate the integer inferior id (GDB's homegrown id, not the system's)
 468    into a "pid" (which may be overloaded with extra inferior information).  */
 469 extern int gdb_inferior_id_to_pid (int);
 470
 471 /* Translate a target 'pid' into the integer inferior id (GDB's
 472    homegrown id, not the system's).  */
 473 extern int pid_to_gdb_inferior_id (int pid);
 474
 475 /* Boolean test for an already-known pid.  */
 476 extern int in_inferior_list (int pid);
 477
 478 /* Boolean test for an already-known inferior id (GDB's homegrown id,
 479    not the system's).  */
 480 extern int valid_gdb_inferior_id (int num);
 481
 482 /* Search function to lookup an inferior by target 'pid'.  */
 483 extern struct inferior *find_inferior_pid (int pid);
 484
 485 /* Search function to lookup an inferior whose pid is equal to 'ptid.pid'. */
 486 extern struct inferior *find_inferior_ptid (ptid_t ptid);
 487
 488 /* Search function to lookup an inferior by GDB 'num'.  */
 489 extern struct inferior *find_inferior_id (int num);
 490
 491 /* Find an inferior bound to PSPACE, giving preference to the current
 492    inferior.  */
 493 extern struct inferior *
 494   find_inferior_for_program_space (struct program_space *pspace);
 495
 496 /* Inferior iterator function.
 497
 498    Calls a callback function once for each inferior, so long as the
 499    callback function returns false.  If the callback function returns
 500    true, the iteration will end and the current inferior will be
 501    returned.  This can be useful for implementing a search for a
 502    inferior with arbitrary attributes, or for applying some operation
 503    to every inferior.
 504
 505    It is safe to delete the iterated inferior from the callback.  */
 506 extern struct inferior *iterate_over_inferiors (int (*) (struct inferior *,
 507                                                          void *),
 508                                                 void *);
 509
 510 /* Returns true if the inferior list is not empty.  */
 511 extern int have_inferiors (void);
 512
 513 /* Returns the number of live inferiors (real live processes).  */
 514 extern int number_of_live_inferiors (void);
 515
 516 /* Returns true if there are any live inferiors in the inferior list
 517    (not cores, not executables, real live processes).  */
 518 extern int have_live_inferiors (void);
 519
 520 /* Return a pointer to the current inferior.  It is an error to call
 521    this if there is no current inferior.  */
 522 extern struct inferior *current_inferior (void);
 523
 524 extern void set_current_inferior (struct inferior *);
 525
 526 extern struct cleanup *save_current_inferior (void);
 527
 528 /* Traverse all inferiors.  */
 529
 530 #define ALL_INFERIORS(I) \
 531   for ((I) = inferior_list; (I); (I) = (I)->next)
 532
 533 /* Traverse all non-exited inferiors.  */
 534
 535 #define ALL_NON_EXITED_INFERIORS(I) \
 536   ALL_INFERIORS (I)                 \
 537     if ((I)->pid != 0)
 538
 539 extern struct inferior *inferior_list;
 540
 541 /* Prune away automatically added inferiors that aren't required
 542    anymore.  */
 543 extern void prune_inferiors (void);
 544
 545 extern int number_of_inferiors (void);
 546
 547 extern struct inferior *add_inferior_with_spaces (void);
 548
 549 /* Print the current selected inferior.  */
 550 extern void print_selected_inferior (struct ui_out *uiout);
 551
 552 #endif /* !defined (INFERIOR_H) */