1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
2 Copyright (C) 2002-2022 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" /* For enum target_stop_reason. */
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. */
134 /* Target ops definitions for a Linux target. */
136 class linux_process_target
: public process_stratum_target
140 int create_inferior (const char *program
,
141 const std::vector
<char *> &program_args
) override
;
143 void post_create_inferior () override
;
145 int attach (unsigned long pid
) override
;
147 int kill (process_info
*proc
) override
;
149 int detach (process_info
*proc
) override
;
151 void mourn (process_info
*proc
) override
;
153 void join (int pid
) override
;
155 bool thread_alive (ptid_t pid
) override
;
157 void resume (thread_resume
*resume_info
, size_t n
) override
;
159 ptid_t
wait (ptid_t ptid
, target_waitstatus
*status
,
160 target_wait_flags options
) override
;
162 void fetch_registers (regcache
*regcache
, int regno
) override
;
164 void store_registers (regcache
*regcache
, int regno
) override
;
166 int prepare_to_access_memory () override
;
168 void done_accessing_memory () override
;
170 int read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
,
173 int write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
,
176 void look_up_symbols () override
;
178 void request_interrupt () override
;
180 bool supports_read_auxv () override
;
182 int read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
183 unsigned int len
) override
;
185 int insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
186 int size
, raw_breakpoint
*bp
) override
;
188 int remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
189 int size
, raw_breakpoint
*bp
) override
;
191 bool stopped_by_sw_breakpoint () override
;
193 bool supports_stopped_by_sw_breakpoint () override
;
195 bool stopped_by_hw_breakpoint () override
;
197 bool supports_stopped_by_hw_breakpoint () override
;
199 bool supports_hardware_single_step () override
;
201 bool stopped_by_watchpoint () override
;
203 CORE_ADDR
stopped_data_address () override
;
205 bool supports_read_offsets () override
;
207 int read_offsets (CORE_ADDR
*text
, CORE_ADDR
*data
) override
;
209 bool supports_get_tls_address () override
;
211 int get_tls_address (thread_info
*thread
, CORE_ADDR offset
,
212 CORE_ADDR load_module
, CORE_ADDR
*address
) override
;
214 bool supports_qxfer_osdata () override
;
216 int qxfer_osdata (const char *annex
, unsigned char *readbuf
,
217 unsigned const char *writebuf
,
218 CORE_ADDR offset
, int len
) override
;
220 bool supports_qxfer_siginfo () override
;
222 int qxfer_siginfo (const char *annex
, unsigned char *readbuf
,
223 unsigned const char *writebuf
,
224 CORE_ADDR offset
, int len
) override
;
226 bool supports_non_stop () override
;
228 bool async (bool enable
) override
;
230 int start_non_stop (bool enable
) override
;
232 bool supports_multi_process () override
;
234 bool supports_fork_events () override
;
236 bool supports_vfork_events () override
;
238 bool supports_exec_events () override
;
240 void handle_new_gdb_connection () override
;
242 int handle_monitor_command (char *mon
) override
;
244 int core_of_thread (ptid_t ptid
) override
;
246 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
247 bool supports_read_loadmap () override
;
249 int read_loadmap (const char *annex
, CORE_ADDR offset
,
250 unsigned char *myaddr
, unsigned int len
) override
;
253 CORE_ADDR
read_pc (regcache
*regcache
) override
;
255 void write_pc (regcache
*regcache
, CORE_ADDR pc
) override
;
257 bool supports_thread_stopped () override
;
259 bool thread_stopped (thread_info
*thread
) override
;
261 void pause_all (bool freeze
) override
;
263 void unpause_all (bool unfreeze
) override
;
265 void stabilize_threads () override
;
267 bool supports_disable_randomization () override
;
269 bool supports_qxfer_libraries_svr4 () override
;
271 int qxfer_libraries_svr4 (const char *annex
,
272 unsigned char *readbuf
,
273 unsigned const char *writebuf
,
274 CORE_ADDR offset
, int len
) override
;
276 bool supports_agent () override
;
278 #ifdef HAVE_LINUX_BTRACE
279 btrace_target_info
*enable_btrace (thread_info
*tp
,
280 const btrace_config
*conf
) override
;
282 int disable_btrace (btrace_target_info
*tinfo
) override
;
284 int read_btrace (btrace_target_info
*tinfo
, buffer
*buf
,
285 enum btrace_read_type type
) override
;
287 int read_btrace_conf (const btrace_target_info
*tinfo
,
288 buffer
*buf
) override
;
291 bool supports_range_stepping () override
;
293 bool supports_pid_to_exec_file () override
;
295 const char *pid_to_exec_file (int pid
) override
;
297 bool supports_multifs () override
;
299 int multifs_open (int pid
, const char *filename
, int flags
,
300 mode_t mode
) override
;
302 int multifs_unlink (int pid
, const char *filename
) override
;
304 ssize_t
multifs_readlink (int pid
, const char *filename
, char *buf
,
305 size_t bufsiz
) override
;
307 const char *thread_name (ptid_t thread
) override
;
310 bool thread_handle (ptid_t ptid
, gdb_byte
**handle
,
311 int *handle_len
) override
;
314 thread_info
*thread_pending_parent (thread_info
*thread
) override
;
315 thread_info
*thread_pending_child (thread_info
*thread
) override
;
317 bool supports_catch_syscall () override
;
319 /* Return the information to access registers. This has public
320 visibility because proc-service uses it. */
321 virtual const regs_info
*get_regs_info () = 0;
325 /* Handle a GNU/Linux extended wait response. If we see a clone,
326 fork, or vfork event, we need to add the new LWP to our list
327 (and return 0 so as not to report the trap to higher layers).
328 If we see an exec event, we will modify ORIG_EVENT_LWP to point
329 to a new LWP representing the new program. */
330 int handle_extended_wait (lwp_info
**orig_event_lwp
, int wstat
);
332 /* Do low-level handling of the event, and check if this is an event we want
333 to report. Is so, store it as a pending status in the lwp_info structure
334 corresponding to LWPID. */
335 void filter_event (int lwpid
, int wstat
);
337 /* Wait for an event from child(ren) WAIT_PTID, and return any that
338 match FILTER_PTID (leaving others pending). The PTIDs can be:
339 minus_one_ptid, to specify any child; a pid PTID, specifying all
340 lwps of a thread group; or a PTID representing a single lwp. Store
341 the stop status through the status pointer WSTAT. OPTIONS is
342 passed to the waitpid call. Return 0 if no event was found and
343 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
344 was found. Return the PID of the stopped child otherwise. */
345 int wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
346 int *wstatp
, int options
);
348 /* Wait for an event from child(ren) PTID. PTIDs can be:
349 minus_one_ptid, to specify any child; a pid PTID, specifying all
350 lwps of a thread group; or a PTID representing a single lwp. Store
351 the stop status through the status pointer WSTAT. OPTIONS is
352 passed to the waitpid call. Return 0 if no event was found and
353 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
354 was found. Return the PID of the stopped child otherwise. */
355 int wait_for_event (ptid_t ptid
, int *wstatp
, int options
);
357 /* Wait for all children to stop for the SIGSTOPs we just queued. */
358 void wait_for_sigstop ();
360 /* Wait for process, returns status. */
361 ptid_t
wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
362 target_wait_flags target_options
);
364 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
365 If SUSPEND, then also increase the suspend count of every LWP,
367 void stop_all_lwps (int suspend
, lwp_info
*except
);
369 /* Stopped LWPs that the client wanted to be running, that don't have
370 pending statuses, are set to run again, except for EXCEPT, if not
371 NULL. This undoes a stop_all_lwps call. */
372 void unstop_all_lwps (int unsuspend
, lwp_info
*except
);
374 /* Start a step-over operation on LWP. When LWP stopped at a
375 breakpoint, to make progress, we need to remove the breakpoint out
376 of the way. If we let other threads run while we do that, they may
377 pass by the breakpoint location and miss hitting it. To avoid
378 that, a step-over momentarily stops all threads while LWP is
379 single-stepped by either hardware or software while the breakpoint
380 is temporarily uninserted from the inferior. When the single-step
381 finishes, we reinsert the breakpoint, and let all threads that are
382 supposed to be running, run again. */
383 void start_step_over (lwp_info
*lwp
);
385 /* If there's a step over in progress, wait until all threads stop
386 (that is, until the stepping thread finishes its step), and
387 unsuspend all lwps. The stepping thread ends with its status
388 pending, which is processed later when we get back to processing
390 void complete_ongoing_step_over ();
392 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
393 start_step_over, if still there, and delete any single-step
394 breakpoints we've set, on non hardware single-step targets.
395 Return true if step over finished. */
396 bool finish_step_over (lwp_info
*lwp
);
398 /* When we finish a step-over, set threads running again. If there's
399 another thread that may need a step-over, now's the time to start
400 it. Eventually, we'll move all threads past their breakpoints. */
401 void proceed_all_lwps ();
403 /* The reason we resume in the caller, is because we want to be able
404 to pass lwp->status_pending as WSTAT, and we need to clear
405 status_pending_p before resuming, otherwise, resume_one_lwp
406 refuses to resume. */
407 bool maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
);
409 /* Move THREAD out of the jump pad. */
410 void move_out_of_jump_pad (thread_info
*thread
);
412 /* Call low_arch_setup on THREAD. */
413 void arch_setup_thread (thread_info
*thread
);
415 #ifdef HAVE_LINUX_USRREGS
416 /* Fetch one register. */
417 void fetch_register (const usrregs_info
*usrregs
, regcache
*regcache
,
420 /* Store one register. */
421 void store_register (const usrregs_info
*usrregs
, regcache
*regcache
,
425 /* Fetch all registers, or just one, from the child process.
426 If REGNO is -1, do this for all registers, skipping any that are
427 assumed to have been retrieved by regsets_fetch_inferior_registers,
428 unless ALL is non-zero.
429 Otherwise, REGNO specifies which register (so we can save time). */
430 void usr_fetch_inferior_registers (const regs_info
*regs_info
,
431 regcache
*regcache
, int regno
, int all
);
433 /* Store our register values back into the inferior.
434 If REGNO is -1, do this for all registers, skipping any that are
435 assumed to have been saved by regsets_store_inferior_registers,
436 unless ALL is non-zero.
437 Otherwise, REGNO specifies which register (so we can save time). */
438 void usr_store_inferior_registers (const regs_info
*regs_info
,
439 regcache
*regcache
, int regno
, int all
);
441 /* Return the PC as read from the regcache of LWP, without any
443 CORE_ADDR
get_pc (lwp_info
*lwp
);
445 /* Called when the LWP stopped for a signal/trap. If it stopped for a
446 trap check what caused it (breakpoint, watchpoint, trace, etc.),
447 and save the result in the LWP's stop_reason field. If it stopped
448 for a breakpoint, decrement the PC if necessary on the lwp's
449 architecture. Returns true if we now have the LWP's stop PC. */
450 bool save_stop_reason (lwp_info
*lwp
);
452 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
453 SIGNAL is nonzero, give it that signal. */
454 void resume_one_lwp_throw (lwp_info
*lwp
, int step
, int signal
,
457 /* Like resume_one_lwp_throw, but no error is thrown if the LWP
458 disappears while we try to resume it. */
459 void resume_one_lwp (lwp_info
*lwp
, int step
, int signal
, siginfo_t
*info
);
461 /* This function is called once per thread. We check the thread's
462 last resume request, which will tell us whether to resume, step, or
463 leave the thread stopped. Any signal the client requested to be
464 delivered has already been enqueued at this point.
466 If any thread that GDB wants running is stopped at an internal
467 breakpoint that needs stepping over, we start a step-over operation
468 on that particular thread, and leave all others stopped. */
469 void proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
471 /* This function is called once per thread. We check the thread's
472 resume request, which will tell us whether to resume, step, or
473 leave the thread stopped; and what signal, if any, it should be
476 For threads which we aren't explicitly told otherwise, we preserve
477 the stepping flag; this is used for stepping over gdbserver-placed
480 If pending_flags was set in any thread, we queue any needed
481 signals, since we won't actually resume. We already have a pending
482 event to report, so we don't need to preserve any step requests;
483 they should be re-issued if necessary. */
484 void resume_one_thread (thread_info
*thread
, bool leave_all_stopped
);
486 /* Return true if this lwp has an interesting status pending. */
487 bool status_pending_p_callback (thread_info
*thread
, ptid_t ptid
);
489 /* Resume LWPs that are currently stopped without any pending status
490 to report, but are resumed from the core's perspective. */
491 void resume_stopped_resumed_lwps (thread_info
*thread
);
493 /* Unsuspend THREAD, except EXCEPT, and proceed. */
494 void unsuspend_and_proceed_one_lwp (thread_info
*thread
, lwp_info
*except
);
496 /* Return true if this lwp still has an interesting status pending.
497 If not (e.g., it had stopped for a breakpoint that is gone), return
499 bool thread_still_has_status_pending (thread_info
*thread
);
501 /* Return true if this lwp is to-be-resumed and has an interesting
503 bool resume_status_pending (thread_info
*thread
);
505 /* Return true if this lwp that GDB wants running is stopped at an
506 internal breakpoint that we need to step over. It assumes that
507 any required STOP_PC adjustment has already been propagated to
508 the inferior's regcache. */
509 bool thread_needs_step_over (thread_info
*thread
);
511 /* Single step via hardware or software single step.
512 Return 1 if hardware single stepping, 0 if software single stepping
513 or can't single step. */
514 int single_step (lwp_info
* lwp
);
516 /* Return true if THREAD is doing hardware single step. */
517 bool maybe_hw_step (thread_info
*thread
);
519 /* Install breakpoints for software single stepping. */
520 void install_software_single_step_breakpoints (lwp_info
*lwp
);
522 /* Fetch the possibly triggered data watchpoint info and store it in
525 On some archs, like x86, that use debug registers to set
526 watchpoints, it's possible that the way to know which watched
527 address trapped, is to check the register that is used to select
528 which address to watch. Problem is, between setting the watchpoint
529 and reading back which data address trapped, the user may change
530 the set of watchpoints, and, as a consequence, GDB changes the
531 debug registers in the inferior. To avoid reading back a stale
532 stopped-data-address when that happens, we cache in LP the fact
533 that a watchpoint trapped, and the corresponding data address, as
534 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
535 registers meanwhile, we have the cached data we can rely on. */
536 bool check_stopped_by_watchpoint (lwp_info
*child
);
538 /* Convert a native/host siginfo object, into/from the siginfo in the
539 layout of the inferiors' architecture. */
540 void siginfo_fixup (siginfo_t
*siginfo
, gdb_byte
*inf_siginfo
,
543 /* Add a process to the common process list, and set its private
545 process_info
*add_linux_process (int pid
, int attached
);
547 /* Add a new thread. */
548 lwp_info
*add_lwp (ptid_t ptid
);
550 /* Delete a thread. */
551 void delete_lwp (lwp_info
*lwp
);
553 public: /* Make this public because it's used from outside. */
554 /* Attach to an inferior process. Returns 0 on success, ERRNO on
556 int attach_lwp (ptid_t ptid
);
558 private: /* Back to private. */
559 /* Detach from LWP. */
560 void detach_one_lwp (lwp_info
*lwp
);
562 /* Detect zombie thread group leaders, and "exit" them. We can't
563 reap their exits until all other threads in the group have
565 void check_zombie_leaders ();
567 /* Convenience function that is called when the kernel reports an exit
568 event. This decides whether to report the event to GDB as a
569 process exit event, a thread exit event, or to suppress the
571 ptid_t
filter_exit_event (lwp_info
*event_child
,
572 target_waitstatus
*ourstatus
);
574 /* Returns true if THREAD is stopped in a jump pad, and we can't
575 move it out, because we need to report the stop event to GDB. For
576 example, if the user puts a breakpoint in the jump pad, it's
577 because she wants to debug it. */
578 bool stuck_in_jump_pad (thread_info
*thread
);
580 /* Convenience wrapper. Returns information about LWP's fast tracepoint
581 collection status. */
582 fast_tpoint_collect_result linux_fast_tracepoint_collecting
583 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
);
585 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
586 Fill *SYSNO with the syscall nr trapped. */
587 void get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
);
589 /* Returns true if GDB is interested in the event_child syscall.
590 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
591 bool gdb_catch_this_syscall (lwp_info
*event_child
);
594 /* The architecture-specific "low" methods are listed below. */
596 /* Architecture-specific setup for the current thread. */
597 virtual void low_arch_setup () = 0;
599 /* Return false if we can fetch/store the register, true if we cannot
600 fetch/store the register. */
601 virtual bool low_cannot_fetch_register (int regno
) = 0;
603 virtual bool low_cannot_store_register (int regno
) = 0;
605 /* Hook to fetch a register in some non-standard way. Used for
606 example by backends that have read-only registers with hardcoded
607 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
608 REGNO was supplied, false if not, and we should fallback to the
609 standard ptrace methods. */
610 virtual bool low_fetch_register (regcache
*regcache
, int regno
);
612 /* Return true if breakpoints are supported. Such targets must
613 implement the GET_PC and SET_PC methods. */
614 virtual bool low_supports_breakpoints ();
616 virtual CORE_ADDR
low_get_pc (regcache
*regcache
);
618 virtual void low_set_pc (regcache
*regcache
, CORE_ADDR newpc
);
620 /* Find the next possible PCs after the current instruction executes.
621 Targets that override this method should also override
622 'supports_software_single_step' to return true. */
623 virtual std::vector
<CORE_ADDR
> low_get_next_pcs (regcache
*regcache
);
625 /* Return true if there is a breakpoint at PC. */
626 virtual bool low_breakpoint_at (CORE_ADDR pc
) = 0;
628 /* Breakpoint and watchpoint related functions. See target.h for
630 virtual int low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
631 int size
, raw_breakpoint
*bp
);
633 virtual int low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
634 int size
, raw_breakpoint
*bp
);
636 virtual bool low_stopped_by_watchpoint ();
638 virtual CORE_ADDR
low_stopped_data_address ();
640 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
641 for registers smaller than an xfer unit). */
642 virtual void low_collect_ptrace_register (regcache
*regcache
, int regno
,
645 virtual void low_supply_ptrace_register (regcache
*regcache
, int regno
,
648 /* Hook to convert from target format to ptrace format and back.
649 Returns true if any conversion was done; false otherwise.
650 If DIRECTION is 1, then copy from INF to NATIVE.
651 If DIRECTION is 0, copy from NATIVE to INF. */
652 virtual bool low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
655 /* Hook to call when a new process is created or attached to.
656 If extra per-process architecture-specific data is needed,
658 virtual arch_process_info
*low_new_process ();
660 /* Hook to call when a process is being deleted. If extra per-process
661 architecture-specific data is needed, delete it here. */
662 virtual void low_delete_process (arch_process_info
*info
);
664 /* Hook to call when a new thread is detected.
665 If extra per-thread architecture-specific data is needed,
667 virtual void low_new_thread (lwp_info
*);
669 /* Hook to call when a thread is being deleted. If extra per-thread
670 architecture-specific data is needed, delete it here. */
671 virtual void low_delete_thread (arch_lwp_info
*);
673 /* Hook to call, if any, when a new fork is attached. */
674 virtual void low_new_fork (process_info
*parent
, process_info
*child
);
676 /* Hook to call prior to resuming a thread. */
677 virtual void low_prepare_to_resume (lwp_info
*lwp
);
679 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
680 success, -1 on failure. */
681 virtual int low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
);
683 /* Returns true if the low target supports range stepping. */
684 virtual bool low_supports_range_stepping ();
686 /* Return true if the target supports catch syscall. Such targets
687 override the low_get_syscall_trapinfo method below. */
688 virtual bool low_supports_catch_syscall ();
690 /* Fill *SYSNO with the syscall nr trapped. Only to be called when
691 inferior is stopped due to SYSCALL_SIGTRAP. */
692 virtual void low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
);
694 /* How many bytes the PC should be decremented after a break. */
695 virtual int low_decr_pc_after_break ();
698 extern linux_process_target
*the_linux_target
;
700 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
701 #define get_lwp_thread(lwp) ((lwp)->thread)
703 /* Information about a signal that is to be delivered to a thread. */
705 struct pending_signal
707 pending_signal (int signal
)
715 /* This struct is recorded in the target_data field of struct thread_info.
717 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
718 GDB protocol representation of the thread ID. Threads also have
719 a "process ID" (poorly named) which is (presently) the same as the
722 There is also ``all_processes'' is keyed by the "overall process ID",
723 which GNU/Linux calls tgid, "thread group ID". */
727 /* If this LWP is a fork child that wasn't reported to GDB yet, return
728 its parent, else nullptr. */
729 lwp_info
*pending_parent () const
731 if (this->fork_relative
== nullptr)
734 gdb_assert (this->fork_relative
->fork_relative
== this);
736 /* In a fork parent/child relationship, the parent has a status pending and
737 the child does not, and a thread can only be in one such relationship
738 at most. So we can recognize who is the parent based on which one has
740 gdb_assert (!!this->status_pending_p
741 != !!this->fork_relative
->status_pending_p
);
743 if (!this->fork_relative
->status_pending_p
)
746 const target_waitstatus
&ws
747 = this->fork_relative
->waitstatus
;
748 gdb_assert (ws
.kind () == TARGET_WAITKIND_FORKED
749 || ws
.kind () == TARGET_WAITKIND_VFORKED
);
751 return this->fork_relative
;
754 /* If this LWP is the parent of a fork child we haven't reported to GDB yet,
755 return that child, else nullptr. */
756 lwp_info
*pending_child () const
758 if (this->fork_relative
== nullptr)
761 gdb_assert (this->fork_relative
->fork_relative
== this);
763 /* In a fork parent/child relationship, the parent has a status pending and
764 the child does not, and a thread can only be in one such relationship
765 at most. So we can recognize who is the parent based on which one has
767 gdb_assert (!!this->status_pending_p
768 != !!this->fork_relative
->status_pending_p
);
770 if (!this->status_pending_p
)
773 const target_waitstatus
&ws
= this->waitstatus
;
774 gdb_assert (ws
.kind () == TARGET_WAITKIND_FORKED
775 || ws
.kind () == TARGET_WAITKIND_VFORKED
);
777 return this->fork_relative
;
780 /* Backlink to the parent object. */
781 struct thread_info
*thread
= nullptr;
783 /* If this flag is set, the next SIGSTOP will be ignored (the
784 process will be immediately resumed). This means that either we
785 sent the SIGSTOP to it ourselves and got some other pending event
786 (so the SIGSTOP is still pending), or that we stopped the
787 inferior implicitly via PTRACE_ATTACH and have not waited for it
789 int stop_expected
= 0;
791 /* When this is true, we shall not try to resume this thread, even
792 if last_resume_kind isn't resume_stop. */
795 /* If this flag is set, the lwp is known to be stopped right now (stop
796 event already received in a wait()). */
799 /* Signal whether we are in a SYSCALL_ENTRY or
800 in a SYSCALL_RETURN event.
802 - TARGET_WAITKIND_SYSCALL_ENTRY
803 - TARGET_WAITKIND_SYSCALL_RETURN */
804 enum target_waitkind syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
806 /* When stopped is set, the last wait status recorded for this lwp. */
809 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
810 this LWP's last event, to pass to GDB without any further
811 processing. This is used to store extended ptrace event
812 information or exit status until it can be reported to GDB. */
813 struct target_waitstatus waitstatus
;
815 /* A pointer to the fork child/parent relative. Valid only while
816 the parent fork event is not reported to higher layers. Used to
817 avoid wildcard vCont actions resuming a fork child before GDB is
818 notified about the parent's fork event. */
819 struct lwp_info
*fork_relative
= nullptr;
821 /* When stopped is set, this is where the lwp last stopped, with
822 decr_pc_after_break already accounted for. If the LWP is
823 running, this is the address at which the lwp was resumed. */
824 CORE_ADDR stop_pc
= 0;
826 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
828 int status_pending_p
= 0;
829 int status_pending
= 0;
831 /* The reason the LWP last stopped, if we need to track it
832 (breakpoint, watchpoint, etc.) */
833 enum target_stop_reason stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
835 /* On architectures where it is possible to know the data address of
836 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
837 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
839 CORE_ADDR stopped_data_address
= 0;
841 /* If this is non-zero, it is a breakpoint to be reinserted at our next
842 stop (SIGTRAP stops only). */
843 CORE_ADDR bp_reinsert
= 0;
845 /* If this flag is set, the last continue operation at the ptrace
846 level on this process was a single-step. */
849 /* Range to single step within. This is a copy of the step range
850 passed along the last resume request. See 'struct
852 CORE_ADDR step_range_start
= 0; /* Inclusive */
853 CORE_ADDR step_range_end
= 0; /* Exclusive */
855 /* If this flag is set, we need to set the event request flags the
856 next time we see this LWP stop. */
857 int must_set_ptrace_flags
= 0;
859 /* A chain of signals that need to be delivered to this process. */
860 std::list
<pending_signal
> pending_signals
;
862 /* A link used when resuming. It is initialized from the resume request,
863 and then processed and cleared in linux_resume_one_lwp. */
864 struct thread_resume
*resume
= nullptr;
866 /* Information bout this lwp's fast tracepoint collection status (is it
867 currently stopped in the jump pad, and if so, before or at/after the
868 relocated instruction). Normally, we won't care about this, but we will
869 if a signal arrives to this lwp while it is collecting. */
870 fast_tpoint_collect_result collecting_fast_tracepoint
871 = fast_tpoint_collect_result::not_collecting
;
873 /* A chain of signals that need to be reported to GDB. These were
874 deferred because the thread was doing a fast tracepoint collect
875 when they arrived. */
876 std::list
<pending_signal
> pending_signals_to_report
;
878 /* When collecting_fast_tracepoint is first found to be 1, we insert
879 a exit-jump-pad-quickly breakpoint. This is it. */
880 struct breakpoint
*exit_jump_pad_bkpt
= nullptr;
883 int thread_known
= 0;
884 /* The thread handle, used for e.g. TLS access. Only valid if
885 THREAD_KNOWN is set. */
886 td_thrhandle_t th
{};
888 /* The pthread_t handle. */
889 thread_t thread_handle
{};
892 /* Arch-specific additions. */
893 struct arch_lwp_info
*arch_private
= nullptr;
896 int linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
);
898 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
900 int linux_attach_lwp (ptid_t ptid
);
902 struct lwp_info
*find_lwp_pid (ptid_t ptid
);
903 /* For linux_stop_lwp see nat/linux-nat.h. */
905 #ifdef HAVE_LINUX_REGSETS
906 void initialize_regsets_info (struct regsets_info
*regsets_info
);
909 void initialize_low_arch (void);
911 void linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
);
912 CORE_ADDR
linux_get_pc_32bit (struct regcache
*regcache
);
914 void linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
);
915 CORE_ADDR
linux_get_pc_64bit (struct regcache
*regcache
);
917 /* From thread-db.c */
918 int thread_db_init (void);
919 void thread_db_detach (struct process_info
*);
920 void thread_db_mourn (struct process_info
*);
921 int thread_db_handle_monitor_command (char *);
922 int thread_db_get_tls_address (struct thread_info
*thread
, CORE_ADDR offset
,
923 CORE_ADDR load_module
, CORE_ADDR
*address
);
924 int thread_db_look_up_one_symbol (const char *name
, CORE_ADDR
*addrp
);
926 /* Called from linux-low.c when a clone event is detected. Upon entry,
927 both the clone and the parent should be stopped. This function does
928 whatever is required have the clone under thread_db's control. */
930 void thread_db_notice_clone (struct thread_info
*parent_thr
, ptid_t child_ptid
);
932 bool thread_db_thread_handle (ptid_t ptid
, gdb_byte
**handle
, int *handle_len
);
934 extern int have_ptrace_getregset
;
936 /* Search for the value with type MATCH in the auxv vector with
937 entries of length WORDSIZE bytes. If found, store the value in
938 *VALP and return 1. If not found or if there is an error, return
941 int linux_get_auxv (int wordsize
, CORE_ADDR match
,
944 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
945 WORDSIZE. If no entry was found, return zero. */
947 CORE_ADDR
linux_get_hwcap (int wordsize
);
949 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
950 WORDSIZE. If no entry was found, return zero. */
952 CORE_ADDR
linux_get_hwcap2 (int wordsize
);
954 #endif /* GDBSERVER_LINUX_LOW_H */