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) 1986-2018 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 continuation;
  34 struct inferior;
  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 /* For gdb_environ.  */
  46 #include "environ.h"
  47
  48 #include "progspace.h"
  49 #include "registry.h"
  50
  51 #include "symfile-add-flags.h"
  52 #include "common/refcounted-object.h"
  53
  54 #include "common-inferior.h"
  55
  56 struct infcall_suspend_state;
  57 struct infcall_control_state;
  58
  59 extern struct infcall_suspend_state *save_infcall_suspend_state (void);
  60 extern struct infcall_control_state *save_infcall_control_state (void);
  61
  62 extern void restore_infcall_suspend_state (struct infcall_suspend_state *);
  63 extern void restore_infcall_control_state (struct infcall_control_state *);
  64
  65 extern struct cleanup *make_cleanup_restore_infcall_suspend_state
  66                                             (struct infcall_suspend_state *);
  67 extern struct cleanup *make_cleanup_restore_infcall_control_state
  68                                             (struct infcall_control_state *);
  69
  70 extern void discard_infcall_suspend_state (struct infcall_suspend_state *);
  71 extern void discard_infcall_control_state (struct infcall_control_state *);
  72
  73 extern readonly_detached_regcache *
  74   get_infcall_suspend_state_regcache (struct infcall_suspend_state *);
  75
  76 extern void set_sigint_trap (void);
  77
  78 extern void clear_sigint_trap (void);
  79
  80 /* Set/get file name for default use for standard in/out in the inferior.  */
  81
  82 extern void set_inferior_io_terminal (const char *terminal_name);
  83 extern const char *get_inferior_io_terminal (void);
  84
  85 /* Collected pid, tid, etc. of the debugged inferior.  When there's
  86    no inferior, ptid_get_pid (inferior_ptid) will be 0.  */
  87
  88 extern ptid_t inferior_ptid;
  89
  90 extern void generic_mourn_inferior (void);
  91
  92 extern CORE_ADDR unsigned_pointer_to_address (struct gdbarch *gdbarch,
  93                                               struct type *type,
  94                                               const gdb_byte *buf);
  95 extern void unsigned_address_to_pointer (struct gdbarch *gdbarch,
  96                                          struct type *type, gdb_byte *buf,
  97                                          CORE_ADDR addr);
  98 extern CORE_ADDR signed_pointer_to_address (struct gdbarch *gdbarch,
  99                                             struct type *type,
 100                                             const gdb_byte *buf);
 101 extern void address_to_signed_pointer (struct gdbarch *gdbarch,
 102                                        struct type *type, gdb_byte *buf,
 103                                        CORE_ADDR addr);
 104
 105 extern void reopen_exec_file (void);
 106
 107 /* From misc files */
 108
 109 extern void default_print_registers_info (struct gdbarch *gdbarch,
 110                                           struct ui_file *file,
 111                                           struct frame_info *frame,
 112                                           int regnum, int all);
 113
 114 /* Default implementation of gdbarch_print_float_info.  Print
 115    the values of all floating point registers.  */
 116
 117 extern void default_print_float_info (struct gdbarch *gdbarch,
 118                                       struct ui_file *file,
 119                                       struct frame_info *frame,
 120                                       const char *args);
 121
 122 extern void child_terminal_info (struct target_ops *self, const char *, int);
 123
 124 extern void info_terminal_command (char *, int);
 125
 126 extern void child_terminal_ours (struct target_ops *self);
 127
 128 extern void child_terminal_ours_for_output (struct target_ops *self);
 129
 130 extern void child_terminal_inferior (struct target_ops *self);
 131
 132 extern void child_terminal_save_inferior (struct target_ops *self);
 133
 134 extern void child_terminal_init (struct target_ops *self);
 135
 136 extern void child_terminal_init_with_pgrp (int pgrp);
 137
 138 extern void child_pass_ctrlc (struct target_ops *self);
 139
 140 extern void child_interrupt (struct target_ops *self);
 141
 142 /* From fork-child.c */
 143
 144 /* Helper function to call STARTUP_INFERIOR with PID and NUM_TRAPS.
 145    This function already calls set_executing.  Return the ptid_t from
 146    STARTUP_INFERIOR.  */
 147 extern ptid_t gdb_startup_inferior (pid_t pid, int num_traps);
 148
 149 extern char *construct_inferior_arguments (int, char **);
 150
 151 /* From infcmd.c */
 152
 153 /* Initial inferior setup.  Determines the exec file is not yet known,
 154    takes any necessary post-attaching actions, fetches the target
 155    description and syncs the shared library list.  */
 156
 157 extern void setup_inferior (int from_tty);
 158
 159 extern void post_create_inferior (struct target_ops *, int);
 160
 161 extern void attach_command (const char *, int);
 162
 163 extern char *get_inferior_args (void);
 164
 165 extern void set_inferior_args (const char *);
 166
 167 extern void set_inferior_args_vector (int, char **);
 168
 169 extern void registers_info (const char *, int);
 170
 171 extern void continue_1 (int all_threads);
 172
 173 extern void interrupt_target_1 (int all_threads);
 174
 175 extern void delete_longjmp_breakpoint_cleanup (void *arg);
 176
 177 extern void detach_command (const char *, int);
 178
 179 extern void notice_new_inferior (ptid_t, int, int);
 180
 181 extern struct value *get_return_value (struct value *function,
 182                                        struct type *value_type);
 183
 184 /* Prepare for execution command.  TARGET is the target that will run
 185    the command.  BACKGROUND determines whether this is a foreground
 186    (synchronous) or background (asynchronous) command.  */
 187
 188 extern void prepare_execution_command (struct target_ops *target,
 189                                        int background);
 190
 191 /* Whether to start up the debuggee under a shell.
 192
 193    If startup-with-shell is set, GDB's "run" will attempt to start up
 194    the debuggee under a shell.
 195
 196    This is in order for argument-expansion to occur.  E.g.,
 197
 198    (gdb) run *
 199
 200    The "*" gets expanded by the shell into a list of files.
 201
 202    While this is a nice feature, it may be handy to bypass the shell
 203    in some cases.  To disable this feature, do "set startup-with-shell
 204    false".
 205
 206    The catch-exec traps expected during start-up will be one more if
 207    the target is started up with a shell.  */
 208 extern int startup_with_shell;
 209
 210 /* Address at which inferior stopped.  */
 211
 212 extern CORE_ADDR stop_pc;
 213
 214 /* Nonzero if stopped due to completion of a stack dummy routine.  */
 215
 216 extern enum stop_stack_kind stop_stack_dummy;
 217
 218 /* Nonzero if program stopped due to a random (unexpected) signal in
 219    inferior process.  */
 220
 221 extern int stopped_by_random_signal;
 222
 223 /* Print notices on inferior events (attach, detach, etc.), set with
 224    `set print inferior-events'.  */
 225 extern int print_inferior_events;
 226
 227 /* STEP_OVER_ALL means step over all subroutine calls.
 228    STEP_OVER_UNDEBUGGABLE means step over calls to undebuggable functions.
 229    STEP_OVER_NONE means don't step over any subroutine calls.  */
 230
 231 enum step_over_calls_kind
 232   {
 233     STEP_OVER_NONE,
 234     STEP_OVER_ALL,
 235     STEP_OVER_UNDEBUGGABLE
 236   };
 237
 238 /* Anything but NO_STOP_QUIETLY means we expect a trap and the caller
 239    will handle it themselves.  STOP_QUIETLY is used when running in
 240    the shell before the child program has been exec'd and when running
 241    through shared library loading.  STOP_QUIETLY_REMOTE is used when
 242    setting up a remote connection; it is like STOP_QUIETLY_NO_SIGSTOP
 243    except that there is no need to hide a signal.  */
 244
 245 /* STOP_QUIETLY_NO_SIGSTOP is used to handle a tricky situation with attach.
 246    When doing an attach, the kernel stops the debuggee with a SIGSTOP.
 247    On newer GNU/Linux kernels (>= 2.5.61) the handling of SIGSTOP for
 248    a ptraced process has changed.  Earlier versions of the kernel
 249    would ignore these SIGSTOPs, while now SIGSTOP is treated like any
 250    other signal, i.e. it is not muffled.
 251
 252    If the gdb user does a 'continue' after the 'attach', gdb passes
 253    the global variable stop_signal (which stores the signal from the
 254    attach, SIGSTOP) to the ptrace(PTRACE_CONT,...)  call.  This is
 255    problematic, because the kernel doesn't ignore such SIGSTOP
 256    now.  I.e. it is reported back to gdb, which in turn presents it
 257    back to the user.
 258
 259    To avoid the problem, we use STOP_QUIETLY_NO_SIGSTOP, which allows
 260    gdb to clear the value of stop_signal after the attach, so that it
 261    is not passed back down to the kernel.  */
 262
 263 enum stop_kind
 264   {
 265     NO_STOP_QUIETLY = 0,
 266     STOP_QUIETLY,
 267     STOP_QUIETLY_REMOTE,
 268     STOP_QUIETLY_NO_SIGSTOP
 269   };
 270
 271 \f
 272 /* Possible values for gdbarch_call_dummy_location.  */
 273 #define ON_STACK 1
 274 #define AT_ENTRY_POINT 4
 275
 276 /* Base class for target-specific inferior data.  */
 277
 278 struct private_inferior
 279 {
 280   virtual ~private_inferior () = 0;
 281 };
 282
 283 /* Inferior process specific part of `struct infcall_control_state'.
 284
 285    Inferior thread counterpart is `struct thread_control_state'.  */
 286
 287 struct inferior_control_state
 288 {
 289   /* See the definition of stop_kind above.  */
 290   enum stop_kind stop_soon;
 291 };
 292
 293 /* Return a pointer to the current inferior.  */
 294 extern inferior *current_inferior ();
 295
 296 extern void set_current_inferior (inferior *);
 297
 298 /* GDB represents the state of each program execution with an object
 299    called an inferior.  An inferior typically corresponds to a process
 300    but is more general and applies also to targets that do not have a
 301    notion of processes.  Each run of an executable creates a new
 302    inferior, as does each attachment to an existing process.
 303    Inferiors have unique internal identifiers that are different from
 304    target process ids.  Each inferior may in turn have multiple
 305    threads running in it.
 306
 307    Inferiors are intrusively refcounted objects.  Unlike thread
 308    objects, being the user-selected inferior is considered a strong
 309    reference and is thus accounted for in the inferior object's
 310    refcount (see set_current_inferior).  When GDB needs to remember
 311    the selected inferior to later restore it, GDB temporarily bumps
 312    the inferior object's refcount, to prevent something deleting the
 313    inferior object before reverting back (e.g., due to a
 314    "remove-inferiors" command (see
 315    make_cleanup_restore_current_thread).  All other inferior
 316    references are considered weak references.  Inferiors are always
 317    listed exactly once in the inferior list, so placing an inferior in
 318    the inferior list is an implicit, not counted strong reference.  */
 319
 320 class inferior : public refcounted_object
 321 {
 322 public:
 323   explicit inferior (int pid);
 324   ~inferior ();
 325
 326   /* Returns true if we can delete this inferior.  */
 327   bool deletable () const { return refcount () == 0; }
 328
 329   /* Pointer to next inferior in singly-linked list of inferiors.  */
 330   struct inferior *next = NULL;
 331
 332   /* Convenient handle (GDB inferior id).  Unique across all
 333      inferiors.  */
 334   int num = 0;
 335
 336   /* Actual target inferior id, usually, a process id.  This matches
 337      the ptid_t.pid member of threads of this inferior.  */
 338   int pid = 0;
 339   /* True if the PID was actually faked by GDB.  */
 340   bool fake_pid_p = false;
 341
 342   /* The highest thread number this inferior ever had.  */
 343   int highest_thread_num = 0;
 344
 345   /* State of GDB control of inferior process execution.
 346      See `struct inferior_control_state'.  */
 347   inferior_control_state control {NO_STOP_QUIETLY};
 348
 349   /* True if this was an auto-created inferior, e.g. created from
 350      following a fork; false, if this inferior was manually added by
 351      the user, and we should not attempt to prune it
 352      automatically.  */
 353   bool removable = false;
 354
 355   /* The address space bound to this inferior.  */
 356   struct address_space *aspace = NULL;
 357
 358   /* The program space bound to this inferior.  */
 359   struct program_space *pspace = NULL;
 360
 361   /* The arguments string to use when running.  */
 362   char *args = NULL;
 363
 364   /* The size of elements in argv.  */
 365   int argc = 0;
 366
 367   /* The vector version of arguments.  If ARGC is nonzero,
 368      then we must compute ARGS from this (via the target).
 369      This is always coming from main's argv and therefore
 370      should never be freed.  */
 371   char **argv = NULL;
 372
 373   /* The current working directory that will be used when starting
 374      this inferior.  */
 375   gdb::unique_xmalloc_ptr<char> cwd;
 376
 377   /* The name of terminal device to use for I/O.  */
 378   char *terminal = NULL;
 379
 380   /* The terminal state as set by the last target_terminal::terminal_*
 381      call.  */
 382   target_terminal_state terminal_state = target_terminal_state::is_ours;
 383
 384   /* Environment to use for running inferior,
 385      in format described in environ.h.  */
 386   gdb_environ environment;
 387
 388   /* True if this child process was attached rather than forked.  */
 389   bool attach_flag = false;
 390
 391   /* If this inferior is a vfork child, then this is the pointer to
 392      its vfork parent, if GDB is still attached to it.  */
 393   inferior *vfork_parent = NULL;
 394
 395   /* If this process is a vfork parent, this is the pointer to the
 396      child.  Since a vfork parent is left frozen by the kernel until
 397      the child execs or exits, a process can only have one vfork child
 398      at a given time.  */
 399   inferior *vfork_child = NULL;
 400
 401   /* True if this inferior should be detached when it's vfork sibling
 402      exits or execs.  */
 403   bool pending_detach = false;
 404
 405   /* True if this inferior is a vfork parent waiting for a vfork child
 406      not under our control to be done with the shared memory region,
 407      either by exiting or execing.  */
 408   bool waiting_for_vfork_done = false;
 409
 410   /* True if we're in the process of detaching from this inferior.  */
 411   bool detaching = false;
 412
 413   /* What is left to do for an execution command after any thread of
 414      this inferior stops.  For continuations associated with a
 415      specific thread, see `struct thread_info'.  */
 416   continuation *continuations = NULL;
 417
 418   /* True if setup_inferior wasn't called for this inferior yet.
 419      Until that is done, we must not access inferior memory or
 420      registers, as we haven't determined the target
 421      architecture/description.  */
 422   bool needs_setup = false;
 423
 424   /* Private data used by the target vector implementation.  */
 425   std::unique_ptr<private_inferior> priv;
 426
 427   /* HAS_EXIT_CODE is true if the inferior exited with an exit code.
 428      In this case, the EXIT_CODE field is also valid.  */
 429   bool has_exit_code = false;
 430   LONGEST exit_code = 0;
 431
 432   /* Default flags to pass to the symbol reading functions.  These are
 433      used whenever a new objfile is created.  */
 434   symfile_add_flags symfile_flags = 0;
 435
 436   /* Info about an inferior's target description (if it's fetched; the
 437      user supplied description's filename, if any; etc.).  */
 438   target_desc_info *tdesc_info = NULL;
 439
 440   /* The architecture associated with the inferior through the
 441      connection to the target.
 442
 443      The architecture vector provides some information that is really
 444      a property of the inferior, accessed through a particular target:
 445      ptrace operations; the layout of certain RSP packets; the
 446      solib_ops vector; etc.  To differentiate architecture accesses to
 447      per-inferior/target properties from
 448      per-thread/per-frame/per-objfile properties, accesses to
 449      per-inferior/target properties should be made through
 450      this gdbarch.  */
 451   struct gdbarch *gdbarch = NULL;
 452
 453   /* Per inferior data-pointers required by other GDB modules.  */
 454   REGISTRY_FIELDS;
 455 };
 456
 457 /* Keep a registry of per-inferior data-pointers required by other GDB
 458    modules.  */
 459
 460 DECLARE_REGISTRY (inferior);
 461
 462 /* Add an inferior to the inferior list, print a message that a new
 463    inferior is found, and return the pointer to the new inferior.
 464    Caller may use this pointer to initialize the private inferior
 465    data.  */
 466 extern struct inferior *add_inferior (int pid);
 467
 468 /* Same as add_inferior, but don't print new inferior notifications to
 469    the CLI.  */
 470 extern struct inferior *add_inferior_silent (int pid);
 471
 472 extern void delete_inferior (struct inferior *todel);
 473
 474 /* Delete an existing inferior list entry, due to inferior detaching.  */
 475 extern void detach_inferior (inferior *inf);
 476
 477 /* Same as the above, but with the inferior specified by PID.  */
 478 extern void detach_inferior (int pid);
 479
 480 extern void exit_inferior (int pid);
 481
 482 extern void exit_inferior_silent (int pid);
 483
 484 extern void exit_inferior_num_silent (int num);
 485
 486 extern void inferior_appeared (struct inferior *inf, int pid);
 487
 488 /* Get rid of all inferiors.  */
 489 extern void discard_all_inferiors (void);
 490
 491 /* Translate the integer inferior id (GDB's homegrown id, not the system's)
 492    into a "pid" (which may be overloaded with extra inferior information).  */
 493 extern int gdb_inferior_id_to_pid (int);
 494
 495 /* Translate a target 'pid' into the integer inferior id (GDB's
 496    homegrown id, not the system's).  */
 497 extern int pid_to_gdb_inferior_id (int pid);
 498
 499 /* Boolean test for an already-known pid.  */
 500 extern int in_inferior_list (int pid);
 501
 502 /* Boolean test for an already-known inferior id (GDB's homegrown id,
 503    not the system's).  */
 504 extern int valid_gdb_inferior_id (int num);
 505
 506 /* Search function to lookup an inferior by target 'pid'.  */
 507 extern struct inferior *find_inferior_pid (int pid);
 508
 509 /* Search function to lookup an inferior whose pid is equal to 'ptid.pid'. */
 510 extern struct inferior *find_inferior_ptid (ptid_t ptid);
 511
 512 /* Search function to lookup an inferior by GDB 'num'.  */
 513 extern struct inferior *find_inferior_id (int num);
 514
 515 /* Find an inferior bound to PSPACE, giving preference to the current
 516    inferior.  */
 517 extern struct inferior *
 518   find_inferior_for_program_space (struct program_space *pspace);
 519
 520 /* Inferior iterator function.
 521
 522    Calls a callback function once for each inferior, so long as the
 523    callback function returns false.  If the callback function returns
 524    true, the iteration will end and the current inferior will be
 525    returned.  This can be useful for implementing a search for a
 526    inferior with arbitrary attributes, or for applying some operation
 527    to every inferior.
 528
 529    It is safe to delete the iterated inferior from the callback.  */
 530 extern struct inferior *iterate_over_inferiors (int (*) (struct inferior *,
 531                                                          void *),
 532                                                 void *);
 533
 534 /* Returns true if the inferior list is not empty.  */
 535 extern int have_inferiors (void);
 536
 537 /* Returns the number of live inferiors (real live processes).  */
 538 extern int number_of_live_inferiors (void);
 539
 540 /* Returns true if there are any live inferiors in the inferior list
 541    (not cores, not executables, real live processes).  */
 542 extern int have_live_inferiors (void);
 543
 544 /* Save/restore the current inferior.  */
 545
 546 class scoped_restore_current_inferior
 547 {
 548 public:
 549   scoped_restore_current_inferior ()
 550     : m_saved_inf (current_inferior ())
 551   {}
 552
 553   ~scoped_restore_current_inferior ()
 554   { set_current_inferior (m_saved_inf); }
 555
 556   DISABLE_COPY_AND_ASSIGN (scoped_restore_current_inferior);
 557
 558 private:
 559   inferior *m_saved_inf;
 560 };
 561
 562
 563 /* Traverse all inferiors.  */
 564
 565 #define ALL_INFERIORS(I) \
 566   for ((I) = inferior_list; (I); (I) = (I)->next)
 567
 568 /* Traverse all non-exited inferiors.  */
 569
 570 #define ALL_NON_EXITED_INFERIORS(I) \
 571   ALL_INFERIORS (I)                 \
 572     if ((I)->pid != 0)
 573
 574 extern struct inferior *inferior_list;
 575
 576 /* Prune away automatically added inferiors that aren't required
 577    anymore.  */
 578 extern void prune_inferiors (void);
 579
 580 extern int number_of_inferiors (void);
 581
 582 extern struct inferior *add_inferior_with_spaces (void);
 583
 584 /* Print the current selected inferior.  */
 585 extern void print_selected_inferior (struct ui_out *uiout);
 586
 587 #endif /* !defined (INFERIOR_H) */