Automatic date update in version.in
[binutils-gdb.git] / gdbserver / linux-low.h
blobd34d27382389bcf3e12824061bac9054a580e744
1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
2 Copyright (C) 2002-2024 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"
24 #include <signal.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"
34 #include <list>
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 *);
41 enum regset_type {
42 GENERAL_REGS,
43 FP_REGS,
44 EXTENDED_REGS,
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
49 regset. */
50 #define NULL_REGSET \
51 { 0, 0, 0, -1, (enum regset_type) -1, NULL, NULL }
53 struct regset_info
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 *". */
58 int nt_type;
59 int size;
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
66 architecture/mode. */
68 struct regsets_info
70 /* The regsets array. */
71 struct regset_info *regsets;
73 /* The number of regsets in the REGSETS array. */
74 int num_regsets;
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;
84 #endif
86 /* Mapping between the general-purpose registers in `struct user'
87 format and GDB's register array layout. */
89 struct usrregs_info
91 /* The number of registers accessible. */
92 int num_regs;
94 /* The registers map. */
95 int *regmap;
98 /* All info needed to access an architecture/mode's registers. */
100 struct regs_info
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;
116 #endif
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. */
129 CORE_ADDR r_debug;
131 /* The /proc/pid/mem file used for reading/writing memory. */
132 int mem_fd;
135 struct lwp_info;
137 /* Target ops definitions for a Linux target. */
139 class linux_process_target : public process_stratum_target
141 public:
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,
170 int len) override;
172 int write_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
173 int len) override;
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;
252 #endif
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 bool any_resumed () override;
264 void pause_all (bool freeze) override;
266 void unpause_all (bool unfreeze) override;
268 void stabilize_threads () override;
270 bool supports_disable_randomization () override;
272 bool supports_qxfer_libraries_svr4 () override;
274 int qxfer_libraries_svr4 (const char *annex,
275 unsigned char *readbuf,
276 unsigned const char *writebuf,
277 CORE_ADDR offset, int len) override;
279 bool supports_agent () override;
281 #ifdef HAVE_LINUX_BTRACE
282 bool supports_btrace () override;
284 btrace_target_info *enable_btrace (thread_info *tp,
285 const btrace_config *conf) override;
287 int disable_btrace (btrace_target_info *tinfo) override;
289 int read_btrace (btrace_target_info *tinfo, std::string *buf,
290 enum btrace_read_type type) override;
292 int read_btrace_conf (const btrace_target_info *tinfo,
293 std::string *buf) override;
294 #endif
296 bool supports_range_stepping () override;
298 bool supports_pid_to_exec_file () override;
300 const char *pid_to_exec_file (int pid) override;
302 bool supports_multifs () override;
304 int multifs_open (int pid, const char *filename, int flags,
305 mode_t mode) override;
307 int multifs_unlink (int pid, const char *filename) override;
309 ssize_t multifs_readlink (int pid, const char *filename, char *buf,
310 size_t bufsiz) override;
312 const char *thread_name (ptid_t thread) override;
314 #if USE_THREAD_DB
315 bool thread_handle (ptid_t ptid, gdb_byte **handle,
316 int *handle_len) override;
317 #endif
319 thread_info *thread_pending_parent (thread_info *thread) override;
320 thread_info *thread_pending_child (thread_info *thread,
321 target_waitkind *kind) override;
323 bool supports_catch_syscall () override;
325 /* Return the information to access registers. This has public
326 visibility because proc-service uses it. */
327 virtual const regs_info *get_regs_info () = 0;
329 private:
331 /* Handle a GNU/Linux extended wait response. If we see a clone,
332 fork, or vfork event, we need to add the new LWP to our list
333 (and return 0 so as not to report the trap to higher layers).
334 If we see an exec event, we will modify ORIG_EVENT_LWP to point
335 to a new LWP representing the new program. */
336 int handle_extended_wait (lwp_info **orig_event_lwp, int wstat);
338 /* Do low-level handling of the event, and check if this is an event we want
339 to report. Is so, store it as a pending status in the lwp_info structure
340 corresponding to LWPID. */
341 void filter_event (int lwpid, int wstat);
343 /* Wait for an event from child(ren) WAIT_PTID, and return any that
344 match FILTER_PTID (leaving others pending). The PTIDs can be:
345 minus_one_ptid, to specify any child; a pid PTID, specifying all
346 lwps of a thread group; or a PTID representing a single lwp. Store
347 the stop status through the status pointer WSTAT. OPTIONS is
348 passed to the waitpid call. Return 0 if no event was found and
349 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
350 was found. Return the PID of the stopped child otherwise. */
351 int wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
352 int *wstatp, int options);
354 /* Wait for an event from child(ren) PTID. PTIDs can be:
355 minus_one_ptid, to specify any child; a pid PTID, specifying all
356 lwps of a thread group; or a PTID representing a single lwp. Store
357 the stop status through the status pointer WSTAT. OPTIONS is
358 passed to the waitpid call. Return 0 if no event was found and
359 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
360 was found. Return the PID of the stopped child otherwise. */
361 int wait_for_event (ptid_t ptid, int *wstatp, int options);
363 /* Wait for all children to stop for the SIGSTOPs we just queued. */
364 void wait_for_sigstop ();
366 /* Wait for process, returns status. */
367 ptid_t wait_1 (ptid_t ptid, target_waitstatus *ourstatus,
368 target_wait_flags target_options);
370 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
371 If SUSPEND, then also increase the suspend count of every LWP,
372 except EXCEPT. */
373 void stop_all_lwps (int suspend, lwp_info *except);
375 /* Stopped LWPs that the client wanted to be running, that don't have
376 pending statuses, are set to run again, except for EXCEPT, if not
377 NULL. This undoes a stop_all_lwps call. */
378 void unstop_all_lwps (int unsuspend, lwp_info *except);
380 /* Start a step-over operation on LWP. When LWP stopped at a
381 breakpoint, to make progress, we need to remove the breakpoint out
382 of the way. If we let other threads run while we do that, they may
383 pass by the breakpoint location and miss hitting it. To avoid
384 that, a step-over momentarily stops all threads while LWP is
385 single-stepped by either hardware or software while the breakpoint
386 is temporarily uninserted from the inferior. When the single-step
387 finishes, we reinsert the breakpoint, and let all threads that are
388 supposed to be running, run again. */
389 void start_step_over (lwp_info *lwp);
391 /* If there's a step over in progress, wait until all threads stop
392 (that is, until the stepping thread finishes its step), and
393 unsuspend all lwps. The stepping thread ends with its status
394 pending, which is processed later when we get back to processing
395 events. */
396 void complete_ongoing_step_over ();
398 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
399 start_step_over, if still there, and delete any single-step
400 breakpoints we've set, on non hardware single-step targets.
401 Return true if step over finished. */
402 bool finish_step_over (lwp_info *lwp);
404 /* When we finish a step-over, set threads running again. If there's
405 another thread that may need a step-over, now's the time to start
406 it. Eventually, we'll move all threads past their breakpoints. */
407 void proceed_all_lwps ();
409 /* The reason we resume in the caller, is because we want to be able
410 to pass lwp->status_pending as WSTAT, and we need to clear
411 status_pending_p before resuming, otherwise, resume_one_lwp
412 refuses to resume. */
413 bool maybe_move_out_of_jump_pad (lwp_info *lwp, int *wstat);
415 /* Move THREAD out of the jump pad. */
416 void move_out_of_jump_pad (thread_info *thread);
418 /* Call low_arch_setup on THREAD. */
419 void arch_setup_thread (thread_info *thread);
421 #ifdef HAVE_LINUX_USRREGS
422 /* Fetch one register. */
423 void fetch_register (const usrregs_info *usrregs, regcache *regcache,
424 int regno);
426 /* Store one register. */
427 void store_register (const usrregs_info *usrregs, regcache *regcache,
428 int regno);
429 #endif
431 /* Fetch all registers, or just one, from the child process.
432 If REGNO is -1, do this for all registers, skipping any that are
433 assumed to have been retrieved by regsets_fetch_inferior_registers,
434 unless ALL is non-zero.
435 Otherwise, REGNO specifies which register (so we can save time). */
436 void usr_fetch_inferior_registers (const regs_info *regs_info,
437 regcache *regcache, int regno, int all);
439 /* Store our register values back into the inferior.
440 If REGNO is -1, do this for all registers, skipping any that are
441 assumed to have been saved by regsets_store_inferior_registers,
442 unless ALL is non-zero.
443 Otherwise, REGNO specifies which register (so we can save time). */
444 void usr_store_inferior_registers (const regs_info *regs_info,
445 regcache *regcache, int regno, int all);
447 /* Return the PC as read from the regcache of LWP, without any
448 adjustment. */
449 CORE_ADDR get_pc (lwp_info *lwp);
451 /* Called when the LWP stopped for a signal/trap. If it stopped for a
452 trap check what caused it (breakpoint, watchpoint, trace, etc.),
453 and save the result in the LWP's stop_reason field. If it stopped
454 for a breakpoint, decrement the PC if necessary on the lwp's
455 architecture. Returns true if we now have the LWP's stop PC. */
456 bool save_stop_reason (lwp_info *lwp);
458 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
459 SIGNAL is nonzero, give it that signal. */
460 void resume_one_lwp_throw (lwp_info *lwp, int step, int signal,
461 siginfo_t *info);
463 /* Like resume_one_lwp_throw, but no error is thrown if the LWP
464 disappears while we try to resume it. */
465 void resume_one_lwp (lwp_info *lwp, int step, int signal, siginfo_t *info);
467 /* This function is called once per thread. We check the thread's
468 last resume request, which will tell us whether to resume, step, or
469 leave the thread stopped. Any signal the client requested to be
470 delivered has already been enqueued at this point.
472 If any thread that GDB wants running is stopped at an internal
473 breakpoint that needs stepping over, we start a step-over operation
474 on that particular thread, and leave all others stopped. */
475 void proceed_one_lwp (thread_info *thread, lwp_info *except);
477 /* This function is called once per thread. We check the thread's
478 resume request, which will tell us whether to resume, step, or
479 leave the thread stopped; and what signal, if any, it should be
480 sent.
482 For threads which we aren't explicitly told otherwise, we preserve
483 the stepping flag; this is used for stepping over gdbserver-placed
484 breakpoints.
486 If pending_flags was set in any thread, we queue any needed
487 signals, since we won't actually resume. We already have a pending
488 event to report, so we don't need to preserve any step requests;
489 they should be re-issued if necessary. */
490 void resume_one_thread (thread_info *thread, bool leave_all_stopped);
492 /* Return true if this lwp has an interesting status pending. */
493 bool status_pending_p_callback (thread_info *thread, ptid_t ptid);
495 /* Resume LWPs that are currently stopped without any pending status
496 to report, but are resumed from the core's perspective. */
497 void resume_stopped_resumed_lwps (thread_info *thread);
499 /* Unsuspend THREAD, except EXCEPT, and proceed. */
500 void unsuspend_and_proceed_one_lwp (thread_info *thread, lwp_info *except);
502 /* Return true if this lwp still has an interesting status pending.
503 If not (e.g., it had stopped for a breakpoint that is gone), return
504 false. */
505 bool thread_still_has_status_pending (thread_info *thread);
507 /* Return true if this lwp is to-be-resumed and has an interesting
508 status pending. */
509 bool resume_status_pending (thread_info *thread);
511 /* Return true if this lwp that GDB wants running is stopped at an
512 internal breakpoint that we need to step over. It assumes that
513 any required STOP_PC adjustment has already been propagated to
514 the inferior's regcache. */
515 bool thread_needs_step_over (thread_info *thread);
517 /* Single step via hardware or software single step.
518 Return 1 if hardware single stepping, 0 if software single stepping
519 or can't single step. */
520 int single_step (lwp_info* lwp);
522 /* Return true if THREAD is doing hardware single step. */
523 bool maybe_hw_step (thread_info *thread);
525 /* Install breakpoints for software single stepping. */
526 void install_software_single_step_breakpoints (lwp_info *lwp);
528 /* Fetch the possibly triggered data watchpoint info and store it in
529 CHILD.
531 On some archs, like x86, that use debug registers to set
532 watchpoints, it's possible that the way to know which watched
533 address trapped, is to check the register that is used to select
534 which address to watch. Problem is, between setting the watchpoint
535 and reading back which data address trapped, the user may change
536 the set of watchpoints, and, as a consequence, GDB changes the
537 debug registers in the inferior. To avoid reading back a stale
538 stopped-data-address when that happens, we cache in LP the fact
539 that a watchpoint trapped, and the corresponding data address, as
540 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
541 registers meanwhile, we have the cached data we can rely on. */
542 bool check_stopped_by_watchpoint (lwp_info *child);
544 /* Convert a native/host siginfo object, into/from the siginfo in the
545 layout of the inferiors' architecture. */
546 void siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo,
547 int direction);
549 /* Add a process to the common process list, and set its private
550 data. */
551 process_info *add_linux_process (int pid, int attached);
553 /* Same as add_linux_process, but don't open the /proc/PID/mem file
554 yet. */
555 process_info *add_linux_process_no_mem_file (int pid, int attached);
557 /* Free resources associated to PROC and remove it. */
558 void remove_linux_process (process_info *proc);
560 /* Add a new thread. */
561 lwp_info *add_lwp (ptid_t ptid);
563 /* Delete a thread. */
564 void delete_lwp (lwp_info *lwp);
566 public: /* Make this public because it's used from outside. */
567 /* Attach to an inferior process. Returns 0 on success, ERRNO on
568 error. */
569 int attach_lwp (ptid_t ptid);
571 private: /* Back to private. */
572 /* Detach from LWP. */
573 void detach_one_lwp (lwp_info *lwp);
575 /* Detect zombie thread group leaders, and "exit" them. We can't
576 reap their exits until all other threads in the group have
577 exited. Returns true if we left any new event pending, false
578 otherwise. */
579 bool check_zombie_leaders ();
581 /* Convenience function that is called when we're about to return an
582 event to the core. If the event is an exit or signalled event,
583 then this decides whether to report it as process-wide event, as
584 a thread exit event, or to suppress it. All other event kinds
585 are passed through unmodified. */
586 ptid_t filter_exit_event (lwp_info *event_child,
587 target_waitstatus *ourstatus);
589 /* Returns true if THREAD is stopped in a jump pad, and we can't
590 move it out, because we need to report the stop event to GDB. For
591 example, if the user puts a breakpoint in the jump pad, it's
592 because she wants to debug it. */
593 bool stuck_in_jump_pad (thread_info *thread);
595 /* Convenience wrapper. Returns information about LWP's fast tracepoint
596 collection status. */
597 fast_tpoint_collect_result linux_fast_tracepoint_collecting
598 (lwp_info *lwp, fast_tpoint_collect_status *status);
600 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
601 Fill *SYSNO with the syscall nr trapped. */
602 void get_syscall_trapinfo (lwp_info *lwp, int *sysno);
604 /* Returns true if GDB is interested in the event_child syscall.
605 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
606 bool gdb_catch_this_syscall (lwp_info *event_child);
608 protected:
609 /* The architecture-specific "low" methods are listed below. */
611 /* Architecture-specific setup for the current thread. */
612 virtual void low_arch_setup () = 0;
614 /* Return false if we can fetch/store the register, true if we cannot
615 fetch/store the register. */
616 virtual bool low_cannot_fetch_register (int regno) = 0;
618 virtual bool low_cannot_store_register (int regno) = 0;
620 /* Hook to fetch a register in some non-standard way. Used for
621 example by backends that have read-only registers with hardcoded
622 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
623 REGNO was supplied, false if not, and we should fallback to the
624 standard ptrace methods. */
625 virtual bool low_fetch_register (regcache *regcache, int regno);
627 /* Return true if breakpoints are supported. Such targets must
628 implement the GET_PC and SET_PC methods. */
629 virtual bool low_supports_breakpoints ();
631 virtual CORE_ADDR low_get_pc (regcache *regcache);
633 virtual void low_set_pc (regcache *regcache, CORE_ADDR newpc);
635 /* Find the next possible PCs after the current instruction executes.
636 Targets that override this method should also override
637 'supports_software_single_step' to return true. */
638 virtual std::vector<CORE_ADDR> low_get_next_pcs (regcache *regcache);
640 /* Return true if there is a breakpoint at PC. */
641 virtual bool low_breakpoint_at (CORE_ADDR pc) = 0;
643 /* Breakpoint and watchpoint related functions. See target.h for
644 comments. */
645 virtual int low_insert_point (raw_bkpt_type type, CORE_ADDR addr,
646 int size, raw_breakpoint *bp);
648 virtual int low_remove_point (raw_bkpt_type type, CORE_ADDR addr,
649 int size, raw_breakpoint *bp);
651 virtual bool low_stopped_by_watchpoint ();
653 virtual CORE_ADDR low_stopped_data_address ();
655 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
656 for registers smaller than an xfer unit). */
657 virtual void low_collect_ptrace_register (regcache *regcache, int regno,
658 char *buf);
660 virtual void low_supply_ptrace_register (regcache *regcache, int regno,
661 const char *buf);
663 /* Hook to convert from target format to ptrace format and back.
664 Returns true if any conversion was done; false otherwise.
665 If DIRECTION is 1, then copy from INF to NATIVE.
666 If DIRECTION is 0, copy from NATIVE to INF. */
667 virtual bool low_siginfo_fixup (siginfo_t *native, gdb_byte *inf,
668 int direction);
670 /* Hook to call when a new process is created or attached to.
671 If extra per-process architecture-specific data is needed,
672 allocate it here. */
673 virtual arch_process_info *low_new_process ();
675 /* Hook to call when a process is being deleted. If extra per-process
676 architecture-specific data is needed, delete it here. */
677 virtual void low_delete_process (arch_process_info *info);
679 /* Hook to call when a new thread is detected.
680 If extra per-thread architecture-specific data is needed,
681 allocate it here. */
682 virtual void low_new_thread (lwp_info *);
684 /* Hook to call when a thread is being deleted. If extra per-thread
685 architecture-specific data is needed, delete it here. */
686 virtual void low_delete_thread (arch_lwp_info *);
688 /* Hook to call, if any, when a new fork is attached. */
689 virtual void low_new_fork (process_info *parent, process_info *child);
691 /* Hook to call prior to resuming a thread. */
692 virtual void low_prepare_to_resume (lwp_info *lwp);
694 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
695 success, -1 on failure. */
696 virtual int low_get_thread_area (int lwpid, CORE_ADDR *addrp);
698 /* Returns true if the low target supports range stepping. */
699 virtual bool low_supports_range_stepping ();
701 /* Return true if the target supports catch syscall. Such targets
702 override the low_get_syscall_trapinfo method below. */
703 virtual bool low_supports_catch_syscall ();
705 /* Fill *SYSNO with the syscall nr trapped. Only to be called when
706 inferior is stopped due to SYSCALL_SIGTRAP. */
707 virtual void low_get_syscall_trapinfo (regcache *regcache, int *sysno);
709 /* How many bytes the PC should be decremented after a break. */
710 virtual int low_decr_pc_after_break ();
713 extern linux_process_target *the_linux_target;
715 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
716 #define get_lwp_thread(lwp) ((lwp)->thread)
718 /* Information about a signal that is to be delivered to a thread. */
720 struct pending_signal
722 pending_signal (int signal)
723 : signal {signal}
726 int signal;
727 siginfo_t info;
730 /* This struct is recorded in the target_data field of struct thread_info.
732 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
733 GDB protocol representation of the thread ID. Threads also have
734 a "process ID" (poorly named) which is (presently) the same as the
735 LWP ID.
737 There is also ``all_processes'' is keyed by the "overall process ID",
738 which GNU/Linux calls tgid, "thread group ID". */
740 struct lwp_info
742 /* If this LWP is a fork/vfork/clone child that wasn't reported to
743 GDB yet, return its parent, else nullptr. */
744 lwp_info *pending_parent () const
746 if (this->relative == nullptr)
747 return nullptr;
749 gdb_assert (this->relative->relative == this);
751 /* In a parent/child relationship, the parent has a status pending and
752 the child does not, and a thread can only be in one such relationship
753 at most. So we can recognize who is the parent based on which one has
754 a pending status. */
755 gdb_assert (!!this->status_pending_p
756 != !!this->relative->status_pending_p);
758 if (!this->relative->status_pending_p)
759 return nullptr;
761 const target_waitstatus &ws
762 = this->relative->waitstatus;
763 gdb_assert (ws.kind () == TARGET_WAITKIND_FORKED
764 || ws.kind () == TARGET_WAITKIND_VFORKED
765 || ws.kind () == TARGET_WAITKIND_THREAD_CLONED);
767 return this->relative; }
769 /* If this LWP is the parent of a fork/vfork/clone child we haven't
770 reported to GDB yet, return that child and fill in KIND with the
771 matching waitkind, otherwise nullptr. */
772 lwp_info *pending_child (target_waitkind *kind) const
774 if (this->relative == nullptr)
775 return nullptr;
777 gdb_assert (this->relative->relative == this);
779 /* In a parent/child relationship, the parent has a status pending and
780 the child does not, and a thread can only be in one such relationship
781 at most. So we can recognize who is the parent based on which one has
782 a pending status. */
783 gdb_assert (!!this->status_pending_p
784 != !!this->relative->status_pending_p);
786 if (!this->status_pending_p)
787 return nullptr;
789 const target_waitstatus &ws = this->waitstatus;
790 gdb_assert (ws.kind () == TARGET_WAITKIND_FORKED
791 || ws.kind () == TARGET_WAITKIND_VFORKED
792 || ws.kind () == TARGET_WAITKIND_THREAD_CLONED);
794 *kind = ws.kind ();
795 return this->relative;
798 /* Backlink to the parent object. */
799 struct thread_info *thread = nullptr;
801 /* If this flag is set, the next SIGSTOP will be ignored (the
802 process will be immediately resumed). This means that either we
803 sent the SIGSTOP to it ourselves and got some other pending event
804 (so the SIGSTOP is still pending), or that we stopped the
805 inferior implicitly via PTRACE_ATTACH and have not waited for it
806 yet. */
807 int stop_expected = 0;
809 /* When this is true, we shall not try to resume this thread, even
810 if last_resume_kind isn't resume_stop. */
811 int suspended = 0;
813 /* If this flag is set, the lwp is known to be stopped right now (stop
814 event already received in a wait()). */
815 int stopped = 0;
817 /* Signal whether we are in a SYSCALL_ENTRY or
818 in a SYSCALL_RETURN event.
819 Values:
820 - TARGET_WAITKIND_SYSCALL_ENTRY
821 - TARGET_WAITKIND_SYSCALL_RETURN */
822 enum target_waitkind syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
824 /* When stopped is set, the last wait status recorded for this lwp. */
825 int last_status = 0;
827 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
828 this LWP's last event, to pass to GDB without any further
829 processing. This is used to store extended ptrace event
830 information or exit status until it can be reported to GDB. */
831 struct target_waitstatus waitstatus;
833 /* A pointer to the fork/vfork/clone child/parent relative (like
834 people, LWPs have relatives). Valid only while the parent
835 fork/vfork/clone event is not reported to higher layers. Used to
836 avoid wildcard vCont actions resuming a fork/vfork/clone child
837 before GDB is notified about the parent's fork/vfork/clone
838 event. */
839 struct lwp_info *relative = nullptr;
841 /* When stopped is set, this is where the lwp last stopped, with
842 decr_pc_after_break already accounted for. If the LWP is
843 running, this is the address at which the lwp was resumed. */
844 CORE_ADDR stop_pc = 0;
846 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
847 been reported. */
848 int status_pending_p = 0;
849 int status_pending = 0;
851 /* The reason the LWP last stopped, if we need to track it
852 (breakpoint, watchpoint, etc.) */
853 enum target_stop_reason stop_reason = TARGET_STOPPED_BY_NO_REASON;
855 /* On architectures where it is possible to know the data address of
856 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
857 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
858 is true. */
859 CORE_ADDR stopped_data_address = 0;
861 /* If this is non-zero, it is a breakpoint to be reinserted at our next
862 stop (SIGTRAP stops only). */
863 CORE_ADDR bp_reinsert = 0;
865 /* If this flag is set, the last continue operation at the ptrace
866 level on this process was a single-step. */
867 int stepping = 0;
869 /* Range to single step within. This is a copy of the step range
870 passed along the last resume request. See 'struct
871 thread_resume'. */
872 CORE_ADDR step_range_start = 0; /* Inclusive */
873 CORE_ADDR step_range_end = 0; /* Exclusive */
875 /* If this flag is set, we need to set the event request flags the
876 next time we see this LWP stop. */
877 int must_set_ptrace_flags = 0;
879 /* A chain of signals that need to be delivered to this process. */
880 std::list<pending_signal> pending_signals;
882 /* A link used when resuming. It is initialized from the resume request,
883 and then processed and cleared in linux_resume_one_lwp. */
884 struct thread_resume *resume = nullptr;
886 /* Information bout this lwp's fast tracepoint collection status (is it
887 currently stopped in the jump pad, and if so, before or at/after the
888 relocated instruction). Normally, we won't care about this, but we will
889 if a signal arrives to this lwp while it is collecting. */
890 fast_tpoint_collect_result collecting_fast_tracepoint
891 = fast_tpoint_collect_result::not_collecting;
893 /* A chain of signals that need to be reported to GDB. These were
894 deferred because the thread was doing a fast tracepoint collect
895 when they arrived. */
896 std::list<pending_signal> pending_signals_to_report;
898 /* When collecting_fast_tracepoint is first found to be 1, we insert
899 a exit-jump-pad-quickly breakpoint. This is it. */
900 struct breakpoint *exit_jump_pad_bkpt = nullptr;
902 #ifdef USE_THREAD_DB
903 int thread_known = 0;
904 /* The thread handle, used for e.g. TLS access. Only valid if
905 THREAD_KNOWN is set. */
906 td_thrhandle_t th {};
908 /* The pthread_t handle. */
909 thread_t thread_handle {};
910 #endif
912 /* Arch-specific additions. */
913 struct arch_lwp_info *arch_private = nullptr;
916 int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);
918 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
919 errno). */
920 int linux_attach_lwp (ptid_t ptid);
922 struct lwp_info *find_lwp_pid (ptid_t ptid);
923 /* For linux_stop_lwp see nat/linux-nat.h. */
925 #ifdef HAVE_LINUX_REGSETS
926 void initialize_regsets_info (struct regsets_info *regsets_info);
927 #endif
929 void initialize_low_arch (void);
931 void linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc);
932 CORE_ADDR linux_get_pc_32bit (struct regcache *regcache);
934 void linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc);
935 CORE_ADDR linux_get_pc_64bit (struct regcache *regcache);
937 /* From thread-db.c */
938 int thread_db_init (void);
939 void thread_db_detach (struct process_info *);
940 void thread_db_mourn (struct process_info *);
941 int thread_db_handle_monitor_command (char *);
942 int thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
943 CORE_ADDR load_module, CORE_ADDR *address);
944 int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp);
946 /* Called from linux-low.c when a clone event is detected. Upon entry,
947 both the clone and the parent should be stopped. This function does
948 whatever is required have the clone under thread_db's control. */
950 void thread_db_notice_clone (struct thread_info *parent_thr, ptid_t child_ptid);
952 bool thread_db_thread_handle (ptid_t ptid, gdb_byte **handle, int *handle_len);
954 extern int have_ptrace_getregset;
956 /* Search for the value with type MATCH in the auxv vector, with entries of
957 length WORDSIZE bytes, of process with pid PID. If found, store the
958 value in *VALP and return 1. If not found or if there is an error,
959 return 0. */
961 int linux_get_auxv (int pid, int wordsize, CORE_ADDR match, CORE_ADDR *valp);
963 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
964 WORDSIZE, of process with pid PID. If no entry was found, return 0. */
966 CORE_ADDR linux_get_hwcap (int pid, int wordsize);
968 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
969 WORDSIZE, of process with pid PID. If no entry was found, return 0. */
971 CORE_ADDR linux_get_hwcap2 (int pid, int wordsize);
973 #endif /* GDBSERVER_LINUX_LOW_H */