1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
2 Copyright (C) 2002-2023 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 #ifndef GDBSERVER_LINUX_LOW_H
20 #define GDBSERVER_LINUX_LOW_H
22 #include "nat/linux-nat.h"
23 #include "nat/gdb_thread_db.h"
26 #include "gdbthread.h"
27 #include "gdb_proc_service.h"
29 /* Included for ptrace type definitions. */
30 #include "nat/linux-ptrace.h"
31 #include "target/waitstatus.h"
32 #include "tracepoint.h"
36 #define PTRACE_XFER_TYPE long
38 #ifdef HAVE_LINUX_REGSETS
39 typedef void (*regset_fill_func
) (struct regcache
*, void *);
40 typedef void (*regset_store_func
) (struct regcache
*, const void *);
45 OPTIONAL_REGS
, /* Do not error if the regset cannot be accessed. */
48 /* The arch's regsets array initializer must be terminated with a NULL
51 { 0, 0, 0, -1, (enum regset_type) -1, NULL, NULL }
55 int get_request
, set_request
;
56 /* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
57 argument and the 4th argument should be "const struct iovec *". */
60 enum regset_type type
;
61 regset_fill_func fill_function
;
62 regset_store_func store_function
;
65 /* Aggregation of all the supported regsets of a given
70 /* The regsets array. */
71 struct regset_info
*regsets
;
73 /* The number of regsets in the REGSETS array. */
76 /* If we get EIO on a regset, do not try it again. Note the set of
77 supported regsets may depend on processor mode on biarch
78 machines. This is a (lazily allocated) array holding one boolean
79 byte (0/1) per regset, with each element corresponding to the
80 regset in the REGSETS array above at the same offset. */
81 char *disabled_regsets
;
86 /* Mapping between the general-purpose registers in `struct user'
87 format and GDB's register array layout. */
91 /* The number of registers accessible. */
94 /* The registers map. */
98 /* All info needed to access an architecture/mode's registers. */
102 /* Regset support bitmap: 1 for registers that are transferred as a part
103 of a regset, 0 for ones that need to be handled individually. This
104 can be NULL if all registers are transferred with regsets or regsets
105 are not supported. */
106 unsigned char *regset_bitmap
;
108 /* Info used when accessing registers with PTRACE_PEEKUSER /
109 PTRACE_POKEUSER. This can be NULL if all registers are
110 transferred with regsets .*/
111 struct usrregs_info
*usrregs
;
113 #ifdef HAVE_LINUX_REGSETS
114 /* Info used when accessing registers with regsets. */
115 struct regsets_info
*regsets_info
;
119 struct process_info_private
121 /* Arch-specific additions. */
122 struct arch_process_info
*arch_private
;
124 /* libthread_db-specific additions. Not NULL if this process has loaded
125 thread_db, and it is active. */
126 struct thread_db
*thread_db
;
128 /* &_r_debug. 0 if not yet determined. -1 if no PT_DYNAMIC in Phdrs. */
131 /* The /proc/pid/mem file used for reading/writing memory. */
137 /* Target ops definitions for a Linux target. */
139 class linux_process_target
: public process_stratum_target
143 int create_inferior (const char *program
,
144 const std::vector
<char *> &program_args
) override
;
146 void post_create_inferior () override
;
148 int attach (unsigned long pid
) override
;
150 int kill (process_info
*proc
) override
;
152 int detach (process_info
*proc
) override
;
154 void mourn (process_info
*proc
) override
;
156 void join (int pid
) override
;
158 bool thread_alive (ptid_t pid
) override
;
160 void resume (thread_resume
*resume_info
, size_t n
) override
;
162 ptid_t
wait (ptid_t ptid
, target_waitstatus
*status
,
163 target_wait_flags options
) override
;
165 void fetch_registers (regcache
*regcache
, int regno
) override
;
167 void store_registers (regcache
*regcache
, int regno
) override
;
169 int read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
,
172 int write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
,
175 void look_up_symbols () override
;
177 void request_interrupt () override
;
179 bool supports_read_auxv () override
;
181 int read_auxv (int pid
, CORE_ADDR offset
, unsigned char *myaddr
,
182 unsigned int len
) override
;
184 int insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
185 int size
, raw_breakpoint
*bp
) override
;
187 int remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
188 int size
, raw_breakpoint
*bp
) override
;
190 bool stopped_by_sw_breakpoint () override
;
192 bool supports_stopped_by_sw_breakpoint () override
;
194 bool stopped_by_hw_breakpoint () override
;
196 bool supports_stopped_by_hw_breakpoint () override
;
198 bool supports_hardware_single_step () override
;
200 bool stopped_by_watchpoint () override
;
202 CORE_ADDR
stopped_data_address () override
;
204 bool supports_read_offsets () override
;
206 int read_offsets (CORE_ADDR
*text
, CORE_ADDR
*data
) override
;
208 bool supports_get_tls_address () override
;
210 int get_tls_address (thread_info
*thread
, CORE_ADDR offset
,
211 CORE_ADDR load_module
, CORE_ADDR
*address
) override
;
213 bool supports_qxfer_osdata () override
;
215 int qxfer_osdata (const char *annex
, unsigned char *readbuf
,
216 unsigned const char *writebuf
,
217 CORE_ADDR offset
, int len
) override
;
219 bool supports_qxfer_siginfo () override
;
221 int qxfer_siginfo (const char *annex
, unsigned char *readbuf
,
222 unsigned const char *writebuf
,
223 CORE_ADDR offset
, int len
) override
;
225 bool supports_non_stop () override
;
227 bool async (bool enable
) override
;
229 int start_non_stop (bool enable
) override
;
231 bool supports_multi_process () override
;
233 bool supports_fork_events () override
;
235 bool supports_vfork_events () override
;
237 gdb_thread_options
supported_thread_options () override
;
239 bool supports_exec_events () override
;
241 void handle_new_gdb_connection () override
;
243 int handle_monitor_command (char *mon
) override
;
245 int core_of_thread (ptid_t ptid
) override
;
247 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
248 bool supports_read_loadmap () override
;
250 int read_loadmap (const char *annex
, CORE_ADDR offset
,
251 unsigned char *myaddr
, unsigned int len
) override
;
254 CORE_ADDR
read_pc (regcache
*regcache
) override
;
256 void write_pc (regcache
*regcache
, CORE_ADDR pc
) override
;
258 bool supports_thread_stopped () override
;
260 bool thread_stopped (thread_info
*thread
) override
;
262 void pause_all (bool freeze
) override
;
264 void unpause_all (bool unfreeze
) override
;
266 void stabilize_threads () override
;
268 bool supports_disable_randomization () override
;
270 bool supports_qxfer_libraries_svr4 () override
;
272 int qxfer_libraries_svr4 (const char *annex
,
273 unsigned char *readbuf
,
274 unsigned const char *writebuf
,
275 CORE_ADDR offset
, int len
) override
;
277 bool supports_agent () override
;
279 #ifdef HAVE_LINUX_BTRACE
280 bool supports_btrace () override
;
282 btrace_target_info
*enable_btrace (thread_info
*tp
,
283 const btrace_config
*conf
) override
;
285 int disable_btrace (btrace_target_info
*tinfo
) override
;
287 int read_btrace (btrace_target_info
*tinfo
, std::string
*buf
,
288 enum btrace_read_type type
) override
;
290 int read_btrace_conf (const btrace_target_info
*tinfo
,
291 std::string
*buf
) override
;
294 bool supports_range_stepping () override
;
296 bool supports_pid_to_exec_file () override
;
298 const char *pid_to_exec_file (int pid
) override
;
300 bool supports_multifs () override
;
302 int multifs_open (int pid
, const char *filename
, int flags
,
303 mode_t mode
) override
;
305 int multifs_unlink (int pid
, const char *filename
) override
;
307 ssize_t
multifs_readlink (int pid
, const char *filename
, char *buf
,
308 size_t bufsiz
) override
;
310 const char *thread_name (ptid_t thread
) override
;
313 bool thread_handle (ptid_t ptid
, gdb_byte
**handle
,
314 int *handle_len
) override
;
317 thread_info
*thread_pending_parent (thread_info
*thread
) override
;
318 thread_info
*thread_pending_child (thread_info
*thread
) override
;
320 bool supports_catch_syscall () override
;
322 /* Return the information to access registers. This has public
323 visibility because proc-service uses it. */
324 virtual const regs_info
*get_regs_info () = 0;
328 /* Handle a GNU/Linux extended wait response. If we see a clone,
329 fork, or vfork event, we need to add the new LWP to our list
330 (and return 0 so as not to report the trap to higher layers).
331 If we see an exec event, we will modify ORIG_EVENT_LWP to point
332 to a new LWP representing the new program. */
333 int handle_extended_wait (lwp_info
**orig_event_lwp
, int wstat
);
335 /* Do low-level handling of the event, and check if this is an event we want
336 to report. Is so, store it as a pending status in the lwp_info structure
337 corresponding to LWPID. */
338 void filter_event (int lwpid
, int wstat
);
340 /* Wait for an event from child(ren) WAIT_PTID, and return any that
341 match FILTER_PTID (leaving others pending). The PTIDs can be:
342 minus_one_ptid, to specify any child; a pid PTID, specifying all
343 lwps of a thread group; or a PTID representing a single lwp. Store
344 the stop status through the status pointer WSTAT. OPTIONS is
345 passed to the waitpid call. Return 0 if no event was found and
346 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
347 was found. Return the PID of the stopped child otherwise. */
348 int wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
349 int *wstatp
, int options
);
351 /* Wait for an event from child(ren) PTID. PTIDs can be:
352 minus_one_ptid, to specify any child; a pid PTID, specifying all
353 lwps of a thread group; or a PTID representing a single lwp. Store
354 the stop status through the status pointer WSTAT. OPTIONS is
355 passed to the waitpid call. Return 0 if no event was found and
356 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
357 was found. Return the PID of the stopped child otherwise. */
358 int wait_for_event (ptid_t ptid
, int *wstatp
, int options
);
360 /* Wait for all children to stop for the SIGSTOPs we just queued. */
361 void wait_for_sigstop ();
363 /* Wait for process, returns status. */
364 ptid_t
wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
365 target_wait_flags target_options
);
367 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
368 If SUSPEND, then also increase the suspend count of every LWP,
370 void stop_all_lwps (int suspend
, lwp_info
*except
);
372 /* Stopped LWPs that the client wanted to be running, that don't have
373 pending statuses, are set to run again, except for EXCEPT, if not
374 NULL. This undoes a stop_all_lwps call. */
375 void unstop_all_lwps (int unsuspend
, lwp_info
*except
);
377 /* Start a step-over operation on LWP. When LWP stopped at a
378 breakpoint, to make progress, we need to remove the breakpoint out
379 of the way. If we let other threads run while we do that, they may
380 pass by the breakpoint location and miss hitting it. To avoid
381 that, a step-over momentarily stops all threads while LWP is
382 single-stepped by either hardware or software while the breakpoint
383 is temporarily uninserted from the inferior. When the single-step
384 finishes, we reinsert the breakpoint, and let all threads that are
385 supposed to be running, run again. */
386 void start_step_over (lwp_info
*lwp
);
388 /* If there's a step over in progress, wait until all threads stop
389 (that is, until the stepping thread finishes its step), and
390 unsuspend all lwps. The stepping thread ends with its status
391 pending, which is processed later when we get back to processing
393 void complete_ongoing_step_over ();
395 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
396 start_step_over, if still there, and delete any single-step
397 breakpoints we've set, on non hardware single-step targets.
398 Return true if step over finished. */
399 bool finish_step_over (lwp_info
*lwp
);
401 /* When we finish a step-over, set threads running again. If there's
402 another thread that may need a step-over, now's the time to start
403 it. Eventually, we'll move all threads past their breakpoints. */
404 void proceed_all_lwps ();
406 /* The reason we resume in the caller, is because we want to be able
407 to pass lwp->status_pending as WSTAT, and we need to clear
408 status_pending_p before resuming, otherwise, resume_one_lwp
409 refuses to resume. */
410 bool maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
);
412 /* Move THREAD out of the jump pad. */
413 void move_out_of_jump_pad (thread_info
*thread
);
415 /* Call low_arch_setup on THREAD. */
416 void arch_setup_thread (thread_info
*thread
);
418 #ifdef HAVE_LINUX_USRREGS
419 /* Fetch one register. */
420 void fetch_register (const usrregs_info
*usrregs
, regcache
*regcache
,
423 /* Store one register. */
424 void store_register (const usrregs_info
*usrregs
, regcache
*regcache
,
428 /* Fetch all registers, or just one, from the child process.
429 If REGNO is -1, do this for all registers, skipping any that are
430 assumed to have been retrieved by regsets_fetch_inferior_registers,
431 unless ALL is non-zero.
432 Otherwise, REGNO specifies which register (so we can save time). */
433 void usr_fetch_inferior_registers (const regs_info
*regs_info
,
434 regcache
*regcache
, int regno
, int all
);
436 /* Store our register values back into the inferior.
437 If REGNO is -1, do this for all registers, skipping any that are
438 assumed to have been saved by regsets_store_inferior_registers,
439 unless ALL is non-zero.
440 Otherwise, REGNO specifies which register (so we can save time). */
441 void usr_store_inferior_registers (const regs_info
*regs_info
,
442 regcache
*regcache
, int regno
, int all
);
444 /* Return the PC as read from the regcache of LWP, without any
446 CORE_ADDR
get_pc (lwp_info
*lwp
);
448 /* Called when the LWP stopped for a signal/trap. If it stopped for a
449 trap check what caused it (breakpoint, watchpoint, trace, etc.),
450 and save the result in the LWP's stop_reason field. If it stopped
451 for a breakpoint, decrement the PC if necessary on the lwp's
452 architecture. Returns true if we now have the LWP's stop PC. */
453 bool save_stop_reason (lwp_info
*lwp
);
455 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
456 SIGNAL is nonzero, give it that signal. */
457 void resume_one_lwp_throw (lwp_info
*lwp
, int step
, int signal
,
460 /* Like resume_one_lwp_throw, but no error is thrown if the LWP
461 disappears while we try to resume it. */
462 void resume_one_lwp (lwp_info
*lwp
, int step
, int signal
, siginfo_t
*info
);
464 /* This function is called once per thread. We check the thread's
465 last resume request, which will tell us whether to resume, step, or
466 leave the thread stopped. Any signal the client requested to be
467 delivered has already been enqueued at this point.
469 If any thread that GDB wants running is stopped at an internal
470 breakpoint that needs stepping over, we start a step-over operation
471 on that particular thread, and leave all others stopped. */
472 void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
474 /* This function is called once per thread. We check the thread's
475 resume request, which will tell us whether to resume, step, or
476 leave the thread stopped; and what signal, if any, it should be
479 For threads which we aren't explicitly told otherwise, we preserve
480 the stepping flag; this is used for stepping over gdbserver-placed
483 If pending_flags was set in any thread, we queue any needed
484 signals, since we won't actually resume. We already have a pending
485 event to report, so we don't need to preserve any step requests;
486 they should be re-issued if necessary. */
487 void resume_one_thread (thread_info
*thread
, bool leave_all_stopped
);
489 /* Return true if this lwp has an interesting status pending. */
490 bool status_pending_p_callback (thread_info
*thread
, ptid_t ptid
);
492 /* Resume LWPs that are currently stopped without any pending status
493 to report, but are resumed from the core's perspective. */
494 void resume_stopped_resumed_lwps (thread_info
*thread
);
496 /* Unsuspend THREAD, except EXCEPT, and proceed. */
497 void unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
499 /* Return true if this lwp still has an interesting status pending.
500 If not (e.g., it had stopped for a breakpoint that is gone), return
502 bool thread_still_has_status_pending (thread_info
*thread
);
504 /* Return true if this lwp is to-be-resumed and has an interesting
506 bool resume_status_pending (thread_info
*thread
);
508 /* Return true if this lwp that GDB wants running is stopped at an
509 internal breakpoint that we need to step over. It assumes that
510 any required STOP_PC adjustment has already been propagated to
511 the inferior's regcache. */
512 bool thread_needs_step_over (thread_info
*thread
);
514 /* Single step via hardware or software single step.
515 Return 1 if hardware single stepping, 0 if software single stepping
516 or can't single step. */
517 int single_step (lwp_info
* lwp
);
519 /* Return true if THREAD is doing hardware single step. */
520 bool maybe_hw_step (thread_info
*thread
);
522 /* Install breakpoints for software single stepping. */
523 void install_software_single_step_breakpoints (lwp_info
*lwp
);
525 /* Fetch the possibly triggered data watchpoint info and store it in
528 On some archs, like x86, that use debug registers to set
529 watchpoints, it's possible that the way to know which watched
530 address trapped, is to check the register that is used to select
531 which address to watch. Problem is, between setting the watchpoint
532 and reading back which data address trapped, the user may change
533 the set of watchpoints, and, as a consequence, GDB changes the
534 debug registers in the inferior. To avoid reading back a stale
535 stopped-data-address when that happens, we cache in LP the fact
536 that a watchpoint trapped, and the corresponding data address, as
537 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
538 registers meanwhile, we have the cached data we can rely on. */
539 bool check_stopped_by_watchpoint (lwp_info
*child
);
541 /* Convert a native/host siginfo object, into/from the siginfo in the
542 layout of the inferiors' architecture. */
543 void siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
,
546 /* Add a process to the common process list, and set its private
548 process_info
*add_linux_process (int pid
, int attached
);
550 /* Same as add_linux_process, but don't open the /proc/PID/mem file
552 process_info
*add_linux_process_no_mem_file (int pid
, int attached
);
554 /* Free resources associated to PROC and remove it. */
555 void remove_linux_process (process_info
*proc
);
557 /* Add a new thread. */
558 lwp_info
*add_lwp (ptid_t ptid
);
560 /* Delete a thread. */
561 void delete_lwp (lwp_info
*lwp
);
563 public: /* Make this public because it's used from outside. */
564 /* Attach to an inferior process. Returns 0 on success, ERRNO on
566 int attach_lwp (ptid_t ptid
);
568 private: /* Back to private. */
569 /* Detach from LWP. */
570 void detach_one_lwp (lwp_info
*lwp
);
572 /* Detect zombie thread group leaders, and "exit" them. We can't
573 reap their exits until all other threads in the group have
575 void check_zombie_leaders ();
577 /* Convenience function that is called when the kernel reports an exit
578 event. This decides whether to report the event to GDB as a
579 process exit event, a thread exit event, or to suppress the
581 ptid_t
filter_exit_event (lwp_info
*event_child
,
582 target_waitstatus
*ourstatus
);
584 /* Returns true if THREAD is stopped in a jump pad, and we can't
585 move it out, because we need to report the stop event to GDB. For
586 example, if the user puts a breakpoint in the jump pad, it's
587 because she wants to debug it. */
588 bool stuck_in_jump_pad (thread_info
*thread
);
590 /* Convenience wrapper. Returns information about LWP's fast tracepoint
591 collection status. */
592 fast_tpoint_collect_result linux_fast_tracepoint_collecting
593 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
);
595 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
596 Fill *SYSNO with the syscall nr trapped. */
597 void get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
);
599 /* Returns true if GDB is interested in the event_child syscall.
600 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
601 bool gdb_catch_this_syscall (lwp_info
*event_child
);
604 /* The architecture-specific "low" methods are listed below. */
606 /* Architecture-specific setup for the current thread. */
607 virtual void low_arch_setup () = 0;
609 /* Return false if we can fetch/store the register, true if we cannot
610 fetch/store the register. */
611 virtual bool low_cannot_fetch_register (int regno
) = 0;
613 virtual bool low_cannot_store_register (int regno
) = 0;
615 /* Hook to fetch a register in some non-standard way. Used for
616 example by backends that have read-only registers with hardcoded
617 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
618 REGNO was supplied, false if not, and we should fallback to the
619 standard ptrace methods. */
620 virtual bool low_fetch_register (regcache
*regcache
, int regno
);
622 /* Return true if breakpoints are supported. Such targets must
623 implement the GET_PC and SET_PC methods. */
624 virtual bool low_supports_breakpoints ();
626 virtual CORE_ADDR
low_get_pc (regcache
*regcache
);
628 virtual void low_set_pc (regcache
*regcache
, CORE_ADDR newpc
);
630 /* Find the next possible PCs after the current instruction executes.
631 Targets that override this method should also override
632 'supports_software_single_step' to return true. */
633 virtual std::vector
<CORE_ADDR
> low_get_next_pcs (regcache
*regcache
);
635 /* Return true if there is a breakpoint at PC. */
636 virtual bool low_breakpoint_at (CORE_ADDR pc
) = 0;
638 /* Breakpoint and watchpoint related functions. See target.h for
640 virtual int low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
641 int size
, raw_breakpoint
*bp
);
643 virtual int low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
644 int size
, raw_breakpoint
*bp
);
646 virtual bool low_stopped_by_watchpoint ();
648 virtual CORE_ADDR
low_stopped_data_address ();
650 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
651 for registers smaller than an xfer unit). */
652 virtual void low_collect_ptrace_register (regcache
*regcache
, int regno
,
655 virtual void low_supply_ptrace_register (regcache
*regcache
, int regno
,
658 /* Hook to convert from target format to ptrace format and back.
659 Returns true if any conversion was done; false otherwise.
660 If DIRECTION is 1, then copy from INF to NATIVE.
661 If DIRECTION is 0, copy from NATIVE to INF. */
662 virtual bool low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
665 /* Hook to call when a new process is created or attached to.
666 If extra per-process architecture-specific data is needed,
668 virtual arch_process_info
*low_new_process ();
670 /* Hook to call when a process is being deleted. If extra per-process
671 architecture-specific data is needed, delete it here. */
672 virtual void low_delete_process (arch_process_info
*info
);
674 /* Hook to call when a new thread is detected.
675 If extra per-thread architecture-specific data is needed,
677 virtual void low_new_thread (lwp_info
*);
679 /* Hook to call when a thread is being deleted. If extra per-thread
680 architecture-specific data is needed, delete it here. */
681 virtual void low_delete_thread (arch_lwp_info
*);
683 /* Hook to call, if any, when a new fork is attached. */
684 virtual void low_new_fork (process_info
*parent
, process_info
*child
);
686 /* Hook to call prior to resuming a thread. */
687 virtual void low_prepare_to_resume (lwp_info
*lwp
);
689 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
690 success, -1 on failure. */
691 virtual int low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
);
693 /* Returns true if the low target supports range stepping. */
694 virtual bool low_supports_range_stepping ();
696 /* Return true if the target supports catch syscall. Such targets
697 override the low_get_syscall_trapinfo method below. */
698 virtual bool low_supports_catch_syscall ();
700 /* Fill *SYSNO with the syscall nr trapped. Only to be called when
701 inferior is stopped due to SYSCALL_SIGTRAP. */
702 virtual void low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
);
704 /* How many bytes the PC should be decremented after a break. */
705 virtual int low_decr_pc_after_break ();
708 extern linux_process_target
*the_linux_target
;
710 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
711 #define get_lwp_thread(lwp) ((lwp)->thread)
713 /* Information about a signal that is to be delivered to a thread. */
715 struct pending_signal
717 pending_signal (int signal
)
725 /* This struct is recorded in the target_data field of struct thread_info.
727 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
728 GDB protocol representation of the thread ID. Threads also have
729 a "process ID" (poorly named) which is (presently) the same as the
732 There is also ``all_processes'' is keyed by the "overall process ID",
733 which GNU/Linux calls tgid, "thread group ID". */
737 /* If this LWP is a fork/vfork/clone child that wasn't reported to
738 GDB yet, return its parent, else nullptr. */
739 lwp_info
*pending_parent () const
741 if (this->relative
== nullptr)
744 gdb_assert (this->relative
->relative
== this);
746 /* In a parent/child relationship, the parent has a status pending and
747 the child does not, and a thread can only be in one such relationship
748 at most. So we can recognize who is the parent based on which one has
750 gdb_assert (!!this->status_pending_p
751 != !!this->relative
->status_pending_p
);
753 if (!this->relative
->status_pending_p
)
756 const target_waitstatus
&ws
757 = this->relative
->waitstatus
;
758 gdb_assert (ws
.kind () == TARGET_WAITKIND_FORKED
759 || ws
.kind () == TARGET_WAITKIND_VFORKED
);
761 return this->relative
; }
763 /* If this LWP is the parent of a fork/vfork/clone child we haven't
764 reported to GDB yet, return that child, else nullptr. */
765 lwp_info
*pending_child () const
767 if (this->relative
== nullptr)
770 gdb_assert (this->relative
->relative
== this);
772 /* In a parent/child relationship, the parent has a status pending and
773 the child does not, and a thread can only be in one such relationship
774 at most. So we can recognize who is the parent based on which one has
776 gdb_assert (!!this->status_pending_p
777 != !!this->relative
->status_pending_p
);
779 if (!this->status_pending_p
)
782 const target_waitstatus
&ws
= this->waitstatus
;
783 gdb_assert (ws
.kind () == TARGET_WAITKIND_FORKED
784 || ws
.kind () == TARGET_WAITKIND_VFORKED
);
786 return this->relative
;
789 /* Backlink to the parent object. */
790 struct thread_info
*thread
= nullptr;
792 /* If this flag is set, the next SIGSTOP will be ignored (the
793 process will be immediately resumed). This means that either we
794 sent the SIGSTOP to it ourselves and got some other pending event
795 (so the SIGSTOP is still pending), or that we stopped the
796 inferior implicitly via PTRACE_ATTACH and have not waited for it
798 int stop_expected
= 0;
800 /* When this is true, we shall not try to resume this thread, even
801 if last_resume_kind isn't resume_stop. */
804 /* If this flag is set, the lwp is known to be stopped right now (stop
805 event already received in a wait()). */
808 /* Signal whether we are in a SYSCALL_ENTRY or
809 in a SYSCALL_RETURN event.
811 - TARGET_WAITKIND_SYSCALL_ENTRY
812 - TARGET_WAITKIND_SYSCALL_RETURN */
813 enum target_waitkind syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
815 /* When stopped is set, the last wait status recorded for this lwp. */
818 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
819 this LWP's last event, to pass to GDB without any further
820 processing. This is used to store extended ptrace event
821 information or exit status until it can be reported to GDB. */
822 struct target_waitstatus waitstatus
;
824 /* A pointer to the fork/vfork/clone child/parent relative (like
825 people, LWPs have relatives). Valid only while the parent
826 fork/vfork/clone event is not reported to higher layers. Used to
827 avoid wildcard vCont actions resuming a fork/vfork/clone child
828 before GDB is notified about the parent's fork/vfork/clone
830 struct lwp_info
*relative
= nullptr;
832 /* When stopped is set, this is where the lwp last stopped, with
833 decr_pc_after_break already accounted for. If the LWP is
834 running, this is the address at which the lwp was resumed. */
835 CORE_ADDR stop_pc
= 0;
837 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
839 int status_pending_p
= 0;
840 int status_pending
= 0;
842 /* The reason the LWP last stopped, if we need to track it
843 (breakpoint, watchpoint, etc.) */
844 enum target_stop_reason stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
846 /* On architectures where it is possible to know the data address of
847 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
848 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
850 CORE_ADDR stopped_data_address
= 0;
852 /* If this is non-zero, it is a breakpoint to be reinserted at our next
853 stop (SIGTRAP stops only). */
854 CORE_ADDR bp_reinsert
= 0;
856 /* If this flag is set, the last continue operation at the ptrace
857 level on this process was a single-step. */
860 /* Range to single step within. This is a copy of the step range
861 passed along the last resume request. See 'struct
863 CORE_ADDR step_range_start
= 0; /* Inclusive */
864 CORE_ADDR step_range_end
= 0; /* Exclusive */
866 /* If this flag is set, we need to set the event request flags the
867 next time we see this LWP stop. */
868 int must_set_ptrace_flags
= 0;
870 /* A chain of signals that need to be delivered to this process. */
871 std::list
<pending_signal
> pending_signals
;
873 /* A link used when resuming. It is initialized from the resume request,
874 and then processed and cleared in linux_resume_one_lwp. */
875 struct thread_resume
*resume
= nullptr;
877 /* Information bout this lwp's fast tracepoint collection status (is it
878 currently stopped in the jump pad, and if so, before or at/after the
879 relocated instruction). Normally, we won't care about this, but we will
880 if a signal arrives to this lwp while it is collecting. */
881 fast_tpoint_collect_result collecting_fast_tracepoint
882 = fast_tpoint_collect_result::not_collecting
;
884 /* A chain of signals that need to be reported to GDB. These were
885 deferred because the thread was doing a fast tracepoint collect
886 when they arrived. */
887 std::list
<pending_signal
> pending_signals_to_report
;
889 /* When collecting_fast_tracepoint is first found to be 1, we insert
890 a exit-jump-pad-quickly breakpoint. This is it. */
891 struct breakpoint
*exit_jump_pad_bkpt
= nullptr;
894 int thread_known
= 0;
895 /* The thread handle, used for e.g. TLS access. Only valid if
896 THREAD_KNOWN is set. */
897 td_thrhandle_t th
{};
899 /* The pthread_t handle. */
900 thread_t thread_handle
{};
903 /* Arch-specific additions. */
904 struct arch_lwp_info
*arch_private
= nullptr;
907 int linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
);
909 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
911 int linux_attach_lwp (ptid_t ptid
);
913 struct lwp_info
*find_lwp_pid (ptid_t ptid
);
914 /* For linux_stop_lwp see nat/linux-nat.h. */
916 #ifdef HAVE_LINUX_REGSETS
917 void initialize_regsets_info (struct regsets_info
*regsets_info
);
920 void initialize_low_arch (void);
922 void linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
);
923 CORE_ADDR
linux_get_pc_32bit (struct regcache
*regcache
);
925 void linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
);
926 CORE_ADDR
linux_get_pc_64bit (struct regcache
*regcache
);
928 /* From thread-db.c */
929 int thread_db_init (void);
930 void thread_db_detach (struct process_info
*);
931 void thread_db_mourn (struct process_info
*);
932 int thread_db_handle_monitor_command (char *);
933 int thread_db_get_tls_address (struct thread_info
*thread
, CORE_ADDR offset
,
934 CORE_ADDR load_module
, CORE_ADDR
*address
);
935 int thread_db_look_up_one_symbol (const char *name
, CORE_ADDR
*addrp
);
937 /* Called from linux-low.c when a clone event is detected. Upon entry,
938 both the clone and the parent should be stopped. This function does
939 whatever is required have the clone under thread_db's control. */
941 void thread_db_notice_clone (struct thread_info
*parent_thr
, ptid_t child_ptid
);
943 bool thread_db_thread_handle (ptid_t ptid
, gdb_byte
**handle
, int *handle_len
);
945 extern int have_ptrace_getregset
;
947 /* Search for the value with type MATCH in the auxv vector, with entries of
948 length WORDSIZE bytes, of process with pid PID. If found, store the
949 value in *VALP and return 1. If not found or if there is an error,
952 int linux_get_auxv (int pid
, int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
);
954 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
955 WORDSIZE, of process with pid PID. If no entry was found, return 0. */
957 CORE_ADDR
linux_get_hwcap (int pid
, int wordsize
);
959 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
960 WORDSIZE, of process with pid PID. If no entry was found, return 0. */
962 CORE_ADDR
linux_get_hwcap2 (int pid
, int wordsize
);
964 #endif /* GDBSERVER_LINUX_LOW_H */