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. 5 6 7 This file is part of GDB. 8 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. 13 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. 18 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/>. */ 21 22 #ifndef GDBTHREAD_H 23 #define GDBTHREAD_H 24 25 struct symtab; 26 27 #include "breakpoint.h" 28 #include "frame.h" 29 #include "ui-out.h" 30 #include "inferior.h" 31 32 struct thread_info 33 { 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) */ 39 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. */ 46 int executing_; 47 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), 54 running ... } */ 55 /* This field is internal to thread.c. Never access it directly, 56 use is_running instead. */ 57 int state_; 58 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. */ 62 int refcount; 63 64 /* User/external stepping state. */ 65 66 /* Step-resume or longjmp-resume breakpoint. */ 67 struct breakpoint *step_resume_breakpoint; 68 69 /* Range to single step within. 70 71 If this is nonzero, respond to a single-step signal by continuing 72 to step if the pc is in this range. 73 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 78 not.). */ 79 CORE_ADDR step_range_start; /* Inclusive */ 80 CORE_ADDR step_range_end; /* Exclusive */ 81 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; 86 87 /* Similarly, the frame ID of the underlying stack frame (skipping 88 any inlined frames). */ 89 struct frame_id step_stack_frame_id; 90 91 int current_line; 92 struct symtab *current_symtab; 93 94 /* Internal stepping state. */ 95 96 /* Record the pc of the thread the last time it stopped. This is 97 maintained by proceed and keep_going, and used in 98 adjust_pc_after_break to distinguish a hardware single-step 99 SIGTRAP from a breakpoint SIGTRAP. */ 100 CORE_ADDR prev_pc; 101 102 /* Nonzero if we are presently stepping over a breakpoint. 103 104 If we hit a breakpoint or watchpoint, and then continue, we need 105 to single step the current thread with breakpoints disabled, to 106 avoid hitting the same breakpoint or watchpoint again. And we 107 should step just a single thread and keep other threads stopped, 108 so that other threads don't miss breakpoints while they are 109 removed. 110 111 So, this variable simultaneously means that we need to single 112 step the current thread, keep other threads stopped, and that 113 breakpoints should be removed while we step. 114 115 This variable is set either: 116 - in proceed, when we resume inferior on user's explicit request 117 - in keep_going, if handle_inferior_event decides we need to 118 step over breakpoint. 119 120 The variable is cleared in normal_stop. The proceed calls 121 wait_for_inferior, which calls handle_inferior_event in a loop, 122 and until wait_for_inferior exits, this variable is changed only 123 by keep_going. */ 124 int trap_expected; 125 126 /* Should we step over breakpoint next time keep_going is called? */ 127 int stepping_over_breakpoint; 128 129 /* Set to TRUE if we should finish single-stepping over a breakpoint 130 after hitting the current step-resume breakpoint. */ 131 int step_after_step_resume_breakpoint; 132 133 /* This is set TRUE when a catchpoint of a shared library event 134 triggers. Since we don't wish to leave the inferior in the 135 solib hook when we report the event, we step the inferior 136 back to user code before stopping and reporting the event. */ 137 int stepping_through_solib_after_catch; 138 139 /* When stepping_through_solib_after_catch is TRUE, this is a 140 list of the catchpoints that should be reported as triggering 141 when we finally do stop stepping. */ 142 bpstat stepping_through_solib_catchpoints; 143 144 /* Per-thread command support. */ 145 146 /* Pointer to what is left to do for an execution command after the 147 target stops. Used only in asynchronous mode, by targets that 148 support async execution. Several execution commands use it. */ 149 struct continuation *continuations; 150 151 /* Similar to the above, but used when a single execution command 152 requires several resume/stop iterations. Used by the step 153 command. */ 154 struct continuation *intermediate_continuations; 155 156 /* Nonzero if the thread is being proceeded for a "finish" command 157 or a similar situation when stop_registers should be saved. */ 158 int proceed_to_finish; 159 160 /* Nonzero if the thread is being proceeded for an inferior function 161 call. */ 162 int in_infcall; 163 164 enum step_over_calls_kind step_over_calls; 165 166 /* Nonzero if stopped due to a step command. */ 167 int stop_step; 168 169 /* If stepping, nonzero means step count is > 1 so don't print frame 170 next time inferior stops if it stops due to stepping. */ 171 int step_multi; 172 173 /* This is used to remember when a fork or vfork event was caught by 174 a catchpoint, and thus the event is to be followed at the next 175 resume of the thread, and not immediately. */ 176 struct target_waitstatus pending_follow; 177 178 /* Last signal that the inferior received (why it stopped). */ 179 enum target_signal stop_signal; 180 181 /* Chain containing status of breakpoint(s) the thread stopped 182 at. */ 183 bpstat stop_bpstat; 184 185 /* True if this thread has been explicitly requested to stop. */ 186 int stop_requested; 187 188 /* Private data used by the target vector implementation. */ 189 struct private_thread_info *private; 190 191 /* Function that is called to free PRIVATE. If this is NULL, then 192 xfree will be called on PRIVATE. */ 193 void (*private_dtor) (struct private_thread_info *); 194 }; 195 196 /* Create an empty thread list, or empty the existing one. */ 197 extern void init_thread_list (void); 198 199 /* Add a thread to the thread list, print a message 200 that a new thread is found, and return the pointer to 201 the new thread. Caller my use this pointer to 202 initialize the private thread data. */ 203 extern struct thread_info *add_thread (ptid_t ptid); 204 205 /* Same as add_thread, but does not print a message 206 about new thread. */ 207 extern struct thread_info *add_thread_silent (ptid_t ptid); 208 209 /* Same as add_thread, and sets the private info. */ 210 extern struct thread_info *add_thread_with_info (ptid_t ptid, 211 struct private_thread_info *); 212 213 /* Delete an existing thread list entry. */ 214 extern void delete_thread (ptid_t); 215 216 /* Delete an existing thread list entry, and be quiet about it. Used 217 after the process this thread having belonged to having already 218 exited, for example. */ 219 extern void delete_thread_silent (ptid_t); 220 221 /* Delete a step_resume_breakpoint from the thread database. */ 222 extern void delete_step_resume_breakpoint (struct thread_info *); 223 224 /* Translate the integer thread id (GDB's homegrown id, not the system's) 225 into a "pid" (which may be overloaded with extra thread information). */ 226 extern ptid_t thread_id_to_pid (int); 227 228 /* Translate a 'pid' (which may be overloaded with extra thread information) 229 into the integer thread id (GDB's homegrown id, not the system's). */ 230 extern int pid_to_thread_id (ptid_t ptid); 231 232 /* Boolean test for an already-known pid (which may be overloaded with 233 extra thread information). */ 234 extern int in_thread_list (ptid_t ptid); 235 236 /* Boolean test for an already-known thread id (GDB's homegrown id, 237 not the system's). */ 238 extern int valid_thread_id (int thread); 239 240 /* Search function to lookup a thread by 'pid'. */ 241 extern struct thread_info *find_thread_ptid (ptid_t ptid); 242 243 /* Find thread by GDB user-visible thread number. */ 244 struct thread_info *find_thread_id (int num); 245 246 /* Finds the first thread of the inferior given by PID. If PID is -1, 247 returns the first thread in the list. */ 248 struct thread_info *first_thread_of_process (int pid); 249 250 /* Returns any thread of process PID. */ 251 extern struct thread_info *any_thread_of_process (int pid); 252 253 /* Returns any non-exited thread of process PID, giving preference for 254 already stopped threads. */ 255 extern struct thread_info *any_live_thread_of_process (int pid); 256 257 /* Change the ptid of thread OLD_PTID to NEW_PTID. */ 258 void thread_change_ptid (ptid_t old_ptid, ptid_t new_ptid); 259 260 /* Iterator function to call a user-provided callback function 261 once for each known thread. */ 262 typedef int (*thread_callback_func) (struct thread_info *, void *); 263 extern struct thread_info *iterate_over_threads (thread_callback_func, void *); 264 265 extern int thread_count (void); 266 267 /* Switch from one thread to another. */ 268 extern void switch_to_thread (ptid_t ptid); 269 270 /* Marks thread PTID is running, or stopped. 271 If PIDGET (PTID) is -1, marks all threads. */ 272 extern void set_running (ptid_t ptid, int running); 273 274 /* Marks or clears thread(s) PTID as having been requested to stop. 275 If PTID is MINUS_ONE_PTID, applies to all threads. If 276 ptid_is_pid(PTID) is true, applies to all threads of the process 277 pointed at by PTID. If STOP, then the THREAD_STOP_REQUESTED 278 observer is called with PTID as argument. */ 279 extern void set_stop_requested (ptid_t ptid, int stop); 280 281 /* NOTE: Since the thread state is not a boolean, most times, you do 282 not want to check it with negation. If you really want to check if 283 the thread is stopped, 284 285 use (good): 286 287 if (is_stopped (ptid)) 288 289 instead of (bad): 290 291 if (!is_running (ptid)) 292 293 The latter also returns true on exited threads, most likelly not 294 what you want. */ 295 296 /* Reports if in the frontend's perpective, thread PTID is running. */ 297 extern int is_running (ptid_t ptid); 298 299 /* Is this thread listed, but known to have exited? We keep it listed 300 (but not visible) until it's safe to delete. */ 301 extern int is_exited (ptid_t ptid); 302 303 /* In the frontend's perpective, is this thread stopped? */ 304 extern int is_stopped (ptid_t ptid); 305 306 /* In the frontend's perpective is there any thread running? */ 307 extern int any_running (void); 308 309 /* Marks thread PTID as executing, or not. If PIDGET (PTID) is -1, 310 marks all threads. 311 312 Note that this is different from the running state. See the 313 description of state_ and executing_ fields of struct 314 thread_info. */ 315 extern void set_executing (ptid_t ptid, int executing); 316 317 /* Reports if thread PTID is executing. */ 318 extern int is_executing (ptid_t ptid); 319 320 /* Merge the executing property of thread PTID over to its thread 321 state property (frontend running/stopped view). 322 323 "not executing" -> "stopped" 324 "executing" -> "running" 325 "exited" -> "exited" 326 327 If PIDGET (PTID) is -1, go over all threads. 328 329 Notifications are only emitted if the thread state did change. */ 330 extern void finish_thread_state (ptid_t ptid); 331 332 /* Same as FINISH_THREAD_STATE, but with an interface suitable to be 333 registered as a cleanup. PTID_P points to the ptid_t that is 334 passed to FINISH_THREAD_STATE. */ 335 extern void finish_thread_state_cleanup (void *ptid_p); 336 337 /* Commands with a prefix of `thread'. */ 338 extern struct cmd_list_element *thread_cmd_list; 339 340 /* Print notices on thread events (attach, detach, etc.), set with 341 `set print thread-events'. */ 342 extern int print_thread_events; 343 344 extern void print_thread_info (struct ui_out *uiout, int thread, 345 int pid); 346 347 extern struct cleanup *make_cleanup_restore_current_thread (void); 348 349 /* Returns a pointer into the thread_info corresponding to 350 INFERIOR_PTID. INFERIOR_PTID *must* be in the thread list. */ 351 extern struct thread_info* inferior_thread (void); 352 353 extern void update_thread_list (void); 354 355 #endif /* GDBTHREAD_H */ 356