1 /* Multi-process/thread control defs for GDB, the GNU debugger.
2 Copyright (C) 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1997, 1998, 1999,
3 2000, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
4 Contributed by Lynx Real-Time Systems, Inc. Los Gatos, CA.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #include "breakpoint.h"
32 /* Inferior thread specific part of `struct infcall_control_state'.
34 Inferior process counterpart is `struct inferior_control_state'. */
36 struct thread_control_state
38 /* User/external stepping state. */
40 /* Range to single step within.
42 If this is nonzero, respond to a single-step signal by continuing
43 to step if the pc is in this range.
45 If step_range_start and step_range_end are both 1, it means to
46 step for a single instruction (FIXME: it might clean up
47 wait_for_inferior in a minor way if this were changed to the
48 address of the instruction and that address plus one. But maybe
50 CORE_ADDR step_range_start; /* Inclusive */
51 CORE_ADDR step_range_end; /* Exclusive */
53 /* Stack frame address as of when stepping command was issued.
54 This is how we know when we step into a subroutine call, and how
55 to set the frame for the breakpoint used to step out. */
56 struct frame_id step_frame_id;
58 /* Similarly, the frame ID of the underlying stack frame (skipping
59 any inlined frames). */
60 struct frame_id step_stack_frame_id;
62 /* Nonzero if we are presently stepping over a breakpoint.
64 If we hit a breakpoint or watchpoint, and then continue, we need
65 to single step the current thread with breakpoints disabled, to
66 avoid hitting the same breakpoint or watchpoint again. And we
67 should step just a single thread and keep other threads stopped,
68 so that other threads don't miss breakpoints while they are
71 So, this variable simultaneously means that we need to single
72 step the current thread, keep other threads stopped, and that
73 breakpoints should be removed while we step.
75 This variable is set either:
76 - in proceed, when we resume inferior on user's explicit request
77 - in keep_going, if handle_inferior_event decides we need to
80 The variable is cleared in normal_stop. The proceed calls
81 wait_for_inferior, which calls handle_inferior_event in a loop,
82 and until wait_for_inferior exits, this variable is changed only
86 /* Nonzero if the thread is being proceeded for a "finish" command
87 or a similar situation when stop_registers should be saved. */
88 int proceed_to_finish;
90 /* Nonzero if the thread is being proceeded for an inferior function
94 enum step_over_calls_kind step_over_calls;
96 /* Nonzero if stopped due to a step command. */
99 /* Chain containing status of breakpoint(s) the thread stopped
104 /* Inferior thread specific part of `struct infcall_suspend_state'.
106 Inferior process counterpart is `struct inferior_suspend_state'. */
108 struct thread_suspend_state
110 /* Last signal that the inferior received (why it stopped). */
111 enum target_signal stop_signal;
116 struct thread_info *next;
117 ptid_t ptid; /* "Actual process id";
118 In fact, this may be overloaded with
119 kernel thread id, etc. */
120 int num; /* Convenient handle (GDB thread id) */
122 /* Non-zero means the thread is executing. Note: this is different
123 from saying that there is an active target and we are stopped at
124 a breakpoint, for instance. This is a real indicator whether the
125 thread is off and running. */
126 /* This field is internal to thread.c. Never access it directly,
127 use is_executing instead. */
130 /* Frontend view of the thread state. Note that the RUNNING/STOPPED
131 states are different from EXECUTING. When the thread is stopped
132 internally while handling an internal event, like a software
133 single-step breakpoint, EXECUTING will be false, but running will
134 still be true. As a possible future extension, this could turn
135 into enum { stopped, exited, stepping, finishing, until(ling),
137 /* This field is internal to thread.c. Never access it directly,
138 use is_running instead. */
141 /* If this is > 0, then it means there's code out there that relies
142 on this thread being listed. Don't delete it from the lists even
143 if we detect it exiting. */
146 /* State of GDB control of inferior thread execution.
147 See `struct thread_control_state'. */
148 struct thread_control_state control;
150 /* State of inferior thread to restore after GDB is done with an inferior
151 call. See `struct thread_suspend_state'. */
152 struct thread_suspend_state suspend;
154 /* User/external stepping state. */
156 /* Step-resume or longjmp-resume breakpoint. */
157 struct breakpoint *step_resume_breakpoint;
160 struct symtab *current_symtab;
162 /* Internal stepping state. */
164 /* Record the pc of the thread the last time it stopped. This is
165 maintained by proceed and keep_going, and used in
166 adjust_pc_after_break to distinguish a hardware single-step
167 SIGTRAP from a breakpoint SIGTRAP. */
170 /* Should we step over breakpoint next time keep_going is called? */
171 int stepping_over_breakpoint;
173 /* Set to TRUE if we should finish single-stepping over a breakpoint
174 after hitting the current step-resume breakpoint. */
175 int step_after_step_resume_breakpoint;
177 /* This is set TRUE when a catchpoint of a shared library event
178 triggers. Since we don't wish to leave the inferior in the
179 solib hook when we report the event, we step the inferior
180 back to user code before stopping and reporting the event. */
181 int stepping_through_solib_after_catch;
183 /* When stepping_through_solib_after_catch is TRUE, this is a
184 list of the catchpoints that should be reported as triggering
185 when we finally do stop stepping. */
186 bpstat stepping_through_solib_catchpoints;
188 /* Per-thread command support. */
190 /* Pointer to what is left to do for an execution command after the
191 target stops. Used only in asynchronous mode, by targets that
192 support async execution. Several execution commands use it. */
193 struct continuation *continuations;
195 /* Similar to the above, but used when a single execution command
196 requires several resume/stop iterations. Used by the step
198 struct continuation *intermediate_continuations;
200 /* If stepping, nonzero means step count is > 1 so don't print frame
201 next time inferior stops if it stops due to stepping. */
204 /* This is used to remember when a fork or vfork event was caught by
205 a catchpoint, and thus the event is to be followed at the next
206 resume of the thread, and not immediately. */
207 struct target_waitstatus pending_follow;
209 /* True if this thread has been explicitly requested to stop. */
212 /* Private data used by the target vector implementation. */
213 struct private_thread_info *private;
215 /* Function that is called to free PRIVATE. If this is NULL, then
216 xfree will be called on PRIVATE. */
217 void (*private_dtor) (struct private_thread_info *);
220 /* Create an empty thread list, or empty the existing one. */
221 extern void init_thread_list (void);
223 /* Add a thread to the thread list, print a message
224 that a new thread is found, and return the pointer to
225 the new thread. Caller my use this pointer to
226 initialize the private thread data. */
227 extern struct thread_info *add_thread (ptid_t ptid);
229 /* Same as add_thread, but does not print a message
231 extern struct thread_info *add_thread_silent (ptid_t ptid);
233 /* Same as add_thread, and sets the private info. */
234 extern struct thread_info *add_thread_with_info (ptid_t ptid,
235 struct private_thread_info *);
237 /* Delete an existing thread list entry. */
238 extern void delete_thread (ptid_t);
240 /* Delete an existing thread list entry, and be quiet about it. Used
241 after the process this thread having belonged to having already
242 exited, for example. */
243 extern void delete_thread_silent (ptid_t);
245 /* Delete a step_resume_breakpoint from the thread database. */
246 extern void delete_step_resume_breakpoint (struct thread_info *);
248 /* Translate the integer thread id (GDB's homegrown id, not the system's)
249 into a "pid" (which may be overloaded with extra thread information). */
250 extern ptid_t thread_id_to_pid (int);
252 /* Translate a 'pid' (which may be overloaded with extra thread information)
253 into the integer thread id (GDB's homegrown id, not the system's). */
254 extern int pid_to_thread_id (ptid_t ptid);
256 /* Boolean test for an already-known pid (which may be overloaded with
257 extra thread information). */
258 extern int in_thread_list (ptid_t ptid);
260 /* Boolean test for an already-known thread id (GDB's homegrown id,
261 not the system's). */
262 extern int valid_thread_id (int thread);
264 /* Search function to lookup a thread by 'pid'. */
265 extern struct thread_info *find_thread_ptid (ptid_t ptid);
267 /* Find thread by GDB user-visible thread number. */
268 struct thread_info *find_thread_id (int num);
270 /* Finds the first thread of the inferior given by PID. If PID is -1,
271 returns the first thread in the list. */
272 struct thread_info *first_thread_of_process (int pid);
274 /* Returns any thread of process PID. */
275 extern struct thread_info *any_thread_of_process (int pid);
277 /* Returns any non-exited thread of process PID, giving preference for
278 already stopped threads. */
279 extern struct thread_info *any_live_thread_of_process (int pid);
281 /* Change the ptid of thread OLD_PTID to NEW_PTID. */
282 void thread_change_ptid (ptid_t old_ptid, ptid_t new_ptid);
284 /* Iterator function to call a user-provided callback function
285 once for each known thread. */
286 typedef int (*thread_callback_func) (struct thread_info *, void *);
287 extern struct thread_info *iterate_over_threads (thread_callback_func, void *);
289 extern int thread_count (void);
291 /* Switch from one thread to another. */
292 extern void switch_to_thread (ptid_t ptid);
294 /* Marks thread PTID is running, or stopped.
295 If PIDGET (PTID) is -1, marks all threads. */
296 extern void set_running (ptid_t ptid, int running);
298 /* Marks or clears thread(s) PTID as having been requested to stop.
299 If PTID is MINUS_ONE_PTID, applies to all threads. If
300 ptid_is_pid(PTID) is true, applies to all threads of the process
301 pointed at by PTID. If STOP, then the THREAD_STOP_REQUESTED
302 observer is called with PTID as argument. */
303 extern void set_stop_requested (ptid_t ptid, int stop);
305 /* NOTE: Since the thread state is not a boolean, most times, you do
306 not want to check it with negation. If you really want to check if
307 the thread is stopped,
311 if (is_stopped (ptid))
315 if (!is_running (ptid))
317 The latter also returns true on exited threads, most likelly not
320 /* Reports if in the frontend's perpective, thread PTID is running. */
321 extern int is_running (ptid_t ptid);
323 /* Is this thread listed, but known to have exited? We keep it listed
324 (but not visible) until it's safe to delete. */
325 extern int is_exited (ptid_t ptid);
327 /* In the frontend's perpective, is this thread stopped? */
328 extern int is_stopped (ptid_t ptid);
330 /* In the frontend's perpective is there any thread running? */
331 extern int any_running (void);
333 /* Marks thread PTID as executing, or not. If PIDGET (PTID) is -1,
336 Note that this is different from the running state. See the
337 description of state_ and executing_ fields of struct
339 extern void set_executing (ptid_t ptid, int executing);
341 /* Reports if thread PTID is executing. */
342 extern int is_executing (ptid_t ptid);
344 /* Merge the executing property of thread PTID over to its thread
345 state property (frontend running/stopped view).
347 "not executing" -> "stopped"
348 "executing" -> "running"
351 If PIDGET (PTID) is -1, go over all threads.
353 Notifications are only emitted if the thread state did change. */
354 extern void finish_thread_state (ptid_t ptid);
356 /* Same as FINISH_THREAD_STATE, but with an interface suitable to be
357 registered as a cleanup. PTID_P points to the ptid_t that is
358 passed to FINISH_THREAD_STATE. */
359 extern void finish_thread_state_cleanup (void *ptid_p);
361 /* Commands with a prefix of `thread'. */
362 extern struct cmd_list_element *thread_cmd_list;
364 /* Print notices on thread events (attach, detach, etc.), set with
365 `set print thread-events'. */
366 extern int print_thread_events;
368 extern void print_thread_info (struct ui_out *uiout, int thread,
371 extern struct cleanup *make_cleanup_restore_current_thread (void);
373 /* Returns a pointer into the thread_info corresponding to
374 INFERIOR_PTID. INFERIOR_PTID *must* be in the thread list. */
375 extern struct thread_info* inferior_thread (void);
377 extern void update_thread_list (void);
379 #endif /* GDBTHREAD_H */