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 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"
34 struct thread_info *next;
35 ptid_t ptid; /* "Actual process id";
36 In fact, this may be overloaded with
37 kernel thread id, etc. */
38 int num; /* Convenient handle (GDB thread id) */
40 /* Non-zero means the thread is executing. Note: this is different
41 from saying that there is an active target and we are stopped at
42 a breakpoint, for instance. This is a real indicator whether the
43 thread is off and running. */
44 /* This field is internal to thread.c. Never access it directly,
45 use is_executing instead. */
48 /* Frontend view of the thread state. Note that the RUNNING/STOPPED
49 states are different from EXECUTING. When the thread is stopped
50 internally while handling an internal event, like a software
51 single-step breakpoint, EXECUTING will be false, but running will
52 still be true. As a possible future extension, this could turn
53 into enum { stopped, exited, stepping, finishing, until(ling),
55 /* This field is internal to thread.c. Never access it directly,
56 use is_running instead. */
59 /* If this is > 0, then it means there's code out there that relies
60 on this thread being listed. Don't delete it from the lists even
61 if we detect it exiting. */
64 /* User/external stepping state. */
66 /* Step-resume or longjmp-resume breakpoint. */
67 struct breakpoint *step_resume_breakpoint;
69 /* Range to single step within.
71 If this is nonzero, respond to a single-step signal by continuing
72 to step if the pc is in this range.
74 If step_range_start and step_range_end are both 1, it means to
75 step for a single instruction (FIXME: it might clean up
76 wait_for_inferior in a minor way if this were changed to the
77 address of the instruction and that address plus one. But maybe
79 CORE_ADDR step_range_start; /* Inclusive */
80 CORE_ADDR step_range_end; /* Exclusive */
82 /* Stack frame address as of when stepping command was issued.
83 This is how we know when we step into a subroutine call, and how
84 to set the frame for the breakpoint used to step out. */
85 struct frame_id step_frame_id;
87 struct symtab *current_symtab;
89 /* Internal stepping state. */
91 /* Record the pc of the thread the last time it stopped. This is
92 maintained by proceed and keep_going, and used in
93 adjust_pc_after_break to distinguish a hardware single-step
94 SIGTRAP from a breakpoint SIGTRAP. */
97 /* Nonzero if we are presently stepping over a breakpoint.
99 If we hit a breakpoint or watchpoint, and then continue, we need
100 to single step the current thread with breakpoints disabled, to
101 avoid hitting the same breakpoint or watchpoint again. And we
102 should step just a single thread and keep other threads stopped,
103 so that other threads don't miss breakpoints while they are
106 So, this variable simultaneously means that we need to single
107 step the current thread, keep other threads stopped, and that
108 breakpoints should be removed while we step.
110 This variable is set either:
111 - in proceed, when we resume inferior on user's explicit request
112 - in keep_going, if handle_inferior_event decides we need to
113 step over breakpoint.
115 The variable is cleared in normal_stop. The proceed calls
116 wait_for_inferior, which calls handle_inferior_event in a loop,
117 and until wait_for_inferior exits, this variable is changed only
121 /* Should we step over breakpoint next time keep_going is called? */
122 int stepping_over_breakpoint;
124 /* Set to TRUE if we should finish single-stepping over a breakpoint
125 after hitting the current step-resume breakpoint. */
126 int step_after_step_resume_breakpoint;
128 /* This is set TRUE when a catchpoint of a shared library event
129 triggers. Since we don't wish to leave the inferior in the
130 solib hook when we report the event, we step the inferior
131 back to user code before stopping and reporting the event. */
132 int stepping_through_solib_after_catch;
134 /* When stepping_through_solib_after_catch is TRUE, this is a
135 list of the catchpoints that should be reported as triggering
136 when we finally do stop stepping. */
137 bpstat stepping_through_solib_catchpoints;
139 /* Per-thread command support. */
141 /* Pointer to what is left to do for an execution command after the
142 target stops. Used only in asynchronous mode, by targets that
143 support async execution. Several execution commands use it. */
144 struct continuation *continuations;
146 /* Similar to the above, but used when a single execution command
147 requires several resume/stop iterations. Used by the step
149 struct continuation *intermediate_continuations;
151 /* Nonzero if the thread is being proceeded for a "finish" command
152 or a similar situation when stop_registers should be saved. */
153 int proceed_to_finish;
155 /* Nonzero if the thread is being proceeded for an inferior function
159 enum step_over_calls_kind step_over_calls;
161 /* Nonzero if stopped due to a step command. */
164 /* If stepping, nonzero means step count is > 1 so don't print frame
165 next time inferior stops if it stops due to stepping. */
168 /* This is used to remember when a fork or vfork event was caught by
169 a catchpoint, and thus the event is to be followed at the next
170 resume of the thread, and not immediately. */
171 struct target_waitstatus pending_follow;
173 /* Last signal that the inferior received (why it stopped). */
174 enum target_signal stop_signal;
176 /* Chain containing status of breakpoint(s) the thread stopped
180 /* True if this thread has been explicitly requested to stop. */
183 /* Private data used by the target vector implementation. */
184 struct private_thread_info *private;
187 /* Create an empty thread list, or empty the existing one. */
188 extern void init_thread_list (void);
190 /* Add a thread to the thread list, print a message
191 that a new thread is found, and return the pointer to
192 the new thread. Caller my use this pointer to
193 initialize the private thread data. */
194 extern struct thread_info *add_thread (ptid_t ptid);
196 /* Same as add_thread, but does not print a message
198 extern struct thread_info *add_thread_silent (ptid_t ptid);
200 /* Same as add_thread, and sets the private info. */
201 extern struct thread_info *add_thread_with_info (ptid_t ptid,
202 struct private_thread_info *);
204 /* Delete an existing thread list entry. */
205 extern void delete_thread (ptid_t);
207 /* Delete an existing thread list entry, and be quiet about it. Used
208 after the process this thread having belonged to having already
209 exited, for example. */
210 extern void delete_thread_silent (ptid_t);
212 /* Delete a step_resume_breakpoint from the thread database. */
213 extern void delete_step_resume_breakpoint (struct thread_info *);
215 /* Translate the integer thread id (GDB's homegrown id, not the system's)
216 into a "pid" (which may be overloaded with extra thread information). */
217 extern ptid_t thread_id_to_pid (int);
219 /* Translate a 'pid' (which may be overloaded with extra thread information)
220 into the integer thread id (GDB's homegrown id, not the system's). */
221 extern int pid_to_thread_id (ptid_t ptid);
223 /* Boolean test for an already-known pid (which may be overloaded with
224 extra thread information). */
225 extern int in_thread_list (ptid_t ptid);
227 /* Boolean test for an already-known thread id (GDB's homegrown id,
228 not the system's). */
229 extern int valid_thread_id (int thread);
231 /* Search function to lookup a thread by 'pid'. */
232 extern struct thread_info *find_thread_pid (ptid_t ptid);
234 /* Find thread by GDB user-visible thread number. */
235 struct thread_info *find_thread_id (int num);
237 /* Finds the first thread of the inferior given by PID. If PID is -1,
238 returns the first thread in the list. */
239 struct thread_info *first_thread_of_process (int pid);
241 /* Change the ptid of thread OLD_PTID to NEW_PTID. */
242 void thread_change_ptid (ptid_t old_ptid, ptid_t new_ptid);
244 /* Iterator function to call a user-provided callback function
245 once for each known thread. */
246 typedef int (*thread_callback_func) (struct thread_info *, void *);
247 extern struct thread_info *iterate_over_threads (thread_callback_func, void *);
249 extern int thread_count (void);
251 /* Switch from one thread to another. */
252 extern void switch_to_thread (ptid_t ptid);
254 /* Marks thread PTID is running, or stopped.
255 If PIDGET (PTID) is -1, marks all threads. */
256 extern void set_running (ptid_t ptid, int running);
258 /* Marks or clears thread(s) PTID as having been requested to stop.
259 If PTID is MINUS_ONE_PTID, applies to all threads. If
260 ptid_is_pid(PTID) is true, applies to all threads of the process
261 pointed at by PTID. If STOP, then the THREAD_STOP_REQUESTED
262 observer is called with PTID as argument. */
263 extern void set_stop_requested (ptid_t ptid, int stop);
265 /* NOTE: Since the thread state is not a boolean, most times, you do
266 not want to check it with negation. If you really want to check if
267 the thread is stopped,
271 if (is_stopped (ptid))
275 if (!is_running (ptid))
277 The latter also returns true on exited threads, most likelly not
280 /* Reports if in the frontend's perpective, thread PTID is running. */
281 extern int is_running (ptid_t ptid);
283 /* Is this thread listed, but known to have exited? We keep it listed
284 (but not visible) until it's safe to delete. */
285 extern int is_exited (ptid_t ptid);
287 /* In the frontend's perpective, is this thread stopped? */
288 extern int is_stopped (ptid_t ptid);
290 /* In the frontend's perpective is there any thread running? */
291 extern int any_running (void);
293 /* Marks thread PTID as executing, or not. If PIDGET (PTID) is -1,
296 Note that this is different from the running state. See the
297 description of state_ and executing_ fields of struct
299 extern void set_executing (ptid_t ptid, int executing);
301 /* Reports if thread PTID is executing. */
302 extern int is_executing (ptid_t ptid);
304 /* Merge the executing property of thread PTID over to its thread
305 state property (frontend running/stopped view).
307 "not executing" -> "stopped"
308 "executing" -> "running"
311 If PIDGET (PTID) is -1, go over all threads.
313 Notifications are only emitted if the thread state did change. */
314 extern void finish_thread_state (ptid_t ptid);
316 /* Same as FINISH_THREAD_STATE, but with an interface suitable to be
317 registered as a cleanup. PTID_P points to the ptid_t that is
318 passed to FINISH_THREAD_STATE. */
319 extern void finish_thread_state_cleanup (void *ptid_p);
321 /* Commands with a prefix of `thread'. */
322 extern struct cmd_list_element *thread_cmd_list;
324 /* Print notices on thread events (attach, detach, etc.), set with
325 `set print thread-events'. */
326 extern int print_thread_events;
328 extern void print_thread_info (struct ui_out *uiout, int thread,
331 extern struct cleanup *make_cleanup_restore_current_thread (void);
333 /* Returns a pointer into the thread_info corresponding to
334 INFERIOR_PTID. INFERIOR_PTID *must* be in the thread list. */
335 extern struct thread_info* inferior_thread (void);
337 #endif /* GDBTHREAD_H */