/* Internal interfaces for the GNU/Linux specific target code for gdbserver.
- Copyright (C) 2002-2020 Free Software Foundation, Inc.
+ Copyright (C) 2002-2021 Free Software Foundation, Inc.
This file is part of GDB.
#include "target/waitstatus.h" /* For enum target_stop_reason. */
#include "tracepoint.h"
+#include <list>
+
#define PTRACE_XFER_TYPE long
#ifdef HAVE_LINUX_REGSETS
struct lwp_info;
-struct linux_target_ops
-{
- /* Architecture-specific setup. */
- void (*arch_setup) (void);
-
- const struct regs_info *(*regs_info) (void);
- int (*cannot_fetch_register) (int);
-
- /* Returns 0 if we can store the register, 1 if we can not
- store the register, and 2 if failure to store the register
- is acceptable. */
- int (*cannot_store_register) (int);
-
- /* Hook to fetch a register in some non-standard way. Used for
- example by backends that have read-only registers with hardcoded
- values (e.g., IA64's gr0/fr0/fr1). Returns true if register
- REGNO was supplied, false if not, and we should fallback to the
- standard ptrace methods. */
- int (*fetch_register) (struct regcache *regcache, int regno);
-
- CORE_ADDR (*get_pc) (struct regcache *regcache);
- void (*set_pc) (struct regcache *regcache, CORE_ADDR newpc);
-
- /* See target.h for details. */
- int (*breakpoint_kind_from_pc) (CORE_ADDR *pcptr);
-
- /* See target.h for details. */
- const gdb_byte *(*sw_breakpoint_from_kind) (int kind, int *size);
-
- /* Find the next possible PCs after the current instruction executes. */
- std::vector<CORE_ADDR> (*get_next_pcs) (struct regcache *regcache);
-
- int decr_pc_after_break;
- int (*breakpoint_at) (CORE_ADDR pc);
-
- /* Breakpoint and watchpoint related functions. See target.h for
- comments. */
- int (*supports_z_point_type) (char z_type);
- int (*insert_point) (enum raw_bkpt_type type, CORE_ADDR addr,
- int size, struct raw_breakpoint *bp);
- int (*remove_point) (enum raw_bkpt_type type, CORE_ADDR addr,
- int size, struct raw_breakpoint *bp);
-
- int (*stopped_by_watchpoint) (void);
- CORE_ADDR (*stopped_data_address) (void);
-
- /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
- for registers smaller than an xfer unit). */
- void (*collect_ptrace_register) (struct regcache *regcache,
- int regno, char *buf);
- void (*supply_ptrace_register) (struct regcache *regcache,
- int regno, const char *buf);
-
- /* Hook to convert from target format to ptrace format and back.
- Returns true if any conversion was done; false otherwise.
- If DIRECTION is 1, then copy from INF to NATIVE.
- If DIRECTION is 0, copy from NATIVE to INF. */
- int (*siginfo_fixup) (siginfo_t *native, gdb_byte *inf, int direction);
-
- /* Hook to call when a new process is created or attached to.
- If extra per-process architecture-specific data is needed,
- allocate it here. */
- struct arch_process_info * (*new_process) (void);
-
- /* Hook to call when a process is being deleted. If extra per-process
- architecture-specific data is needed, delete it here. */
- void (*delete_process) (struct arch_process_info *info);
-
- /* Hook to call when a new thread is detected.
- If extra per-thread architecture-specific data is needed,
- allocate it here. */
- void (*new_thread) (struct lwp_info *);
-
- /* Hook to call when a thread is being deleted. If extra per-thread
- architecture-specific data is needed, delete it here. */
- void (*delete_thread) (struct arch_lwp_info *);
-
- /* Hook to call, if any, when a new fork is attached. */
- void (*new_fork) (struct process_info *parent, struct process_info *child);
-
- /* Hook to call prior to resuming a thread. */
- void (*prepare_to_resume) (struct lwp_info *);
-
- /* Hook to support target specific qSupported. */
- void (*process_qsupported) (char **, int count);
-
- /* Returns true if the low target supports tracepoints. */
- int (*supports_tracepoints) (void);
-
- /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
- success, -1 on failure. */
- int (*get_thread_area) (int lwpid, CORE_ADDR *addrp);
-
- /* Install a fast tracepoint jump pad. See target.h for
- comments. */
- int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
- CORE_ADDR collector,
- CORE_ADDR lockaddr,
- ULONGEST orig_size,
- CORE_ADDR *jump_entry,
- CORE_ADDR *trampoline,
- ULONGEST *trampoline_size,
- unsigned char *jjump_pad_insn,
- ULONGEST *jjump_pad_insn_size,
- CORE_ADDR *adjusted_insn_addr,
- CORE_ADDR *adjusted_insn_addr_end,
- char *err);
-
- /* Return the bytecode operations vector for the current inferior.
- Returns NULL if bytecode compilation is not supported. */
- struct emit_ops *(*emit_ops) (void);
-
- /* Return the minimum length of an instruction that can be safely overwritten
- for use as a fast tracepoint. */
- int (*get_min_fast_tracepoint_insn_len) (void);
-
- /* Returns true if the low target supports range stepping. */
- int (*supports_range_stepping) (void);
-
- /* See target.h. */
- int (*breakpoint_kind_from_current_state) (CORE_ADDR *pcptr);
-
- /* See target.h. */
- int (*supports_hardware_single_step) (void);
-
- /* Fill *SYSNO with the syscall nr trapped. Only to be called when
- inferior is stopped due to SYSCALL_SIGTRAP. */
- void (*get_syscall_trapinfo) (struct regcache *regcache, int *sysno);
-
- /* See target.h. */
- int (*get_ipa_tdesc_idx) (void);
-};
-
-extern struct linux_target_ops the_low_target;
-
/* Target ops definitions for a Linux target. */
-class linux_process_target : public process_target
+class linux_process_target : public process_stratum_target
{
public:
void resume (thread_resume *resume_info, size_t n) override;
ptid_t wait (ptid_t ptid, target_waitstatus *status,
- int options) override;
+ target_wait_flags options) override;
void fetch_registers (regcache *regcache, int regno) override;
int read_auxv (CORE_ADDR offset, unsigned char *myaddr,
unsigned int len) override;
- bool supports_z_point_type (char z_type) override;
-
int insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
int size, raw_breakpoint *bp) override;
int get_tls_address (thread_info *thread, CORE_ADDR offset,
CORE_ADDR load_module, CORE_ADDR *address) override;
+
+ bool supports_qxfer_osdata () override;
+
+ int qxfer_osdata (const char *annex, unsigned char *readbuf,
+ unsigned const char *writebuf,
+ CORE_ADDR offset, int len) override;
+
+ bool supports_qxfer_siginfo () override;
+
+ int qxfer_siginfo (const char *annex, unsigned char *readbuf,
+ unsigned const char *writebuf,
+ CORE_ADDR offset, int len) override;
+
+ bool supports_non_stop () override;
+
+ bool async (bool enable) override;
+
+ int start_non_stop (bool enable) override;
+
+ bool supports_multi_process () override;
+
+ bool supports_fork_events () override;
+
+ bool supports_vfork_events () override;
+
+ bool supports_exec_events () override;
+
+ void handle_new_gdb_connection () override;
+
+ int handle_monitor_command (char *mon) override;
+
+ int core_of_thread (ptid_t ptid) override;
+
+#if defined PT_GETDSBT || defined PTRACE_GETFDPIC
+ bool supports_read_loadmap () override;
+
+ int read_loadmap (const char *annex, CORE_ADDR offset,
+ unsigned char *myaddr, unsigned int len) override;
+#endif
+
+ CORE_ADDR read_pc (regcache *regcache) override;
+
+ void write_pc (regcache *regcache, CORE_ADDR pc) override;
+
+ bool supports_thread_stopped () override;
+
+ bool thread_stopped (thread_info *thread) override;
+
+ void pause_all (bool freeze) override;
+
+ void unpause_all (bool unfreeze) override;
+
+ void stabilize_threads () override;
+
+ bool supports_disable_randomization () override;
+
+ bool supports_qxfer_libraries_svr4 () override;
+
+ int qxfer_libraries_svr4 (const char *annex,
+ unsigned char *readbuf,
+ unsigned const char *writebuf,
+ CORE_ADDR offset, int len) override;
+
+ bool supports_agent () override;
+
+#ifdef HAVE_LINUX_BTRACE
+ btrace_target_info *enable_btrace (ptid_t ptid,
+ const btrace_config *conf) override;
+
+ int disable_btrace (btrace_target_info *tinfo) override;
+
+ int read_btrace (btrace_target_info *tinfo, buffer *buf,
+ enum btrace_read_type type) override;
+
+ int read_btrace_conf (const btrace_target_info *tinfo,
+ buffer *buf) override;
+#endif
+
+ bool supports_range_stepping () override;
+
+ bool supports_pid_to_exec_file () override;
+
+ const char *pid_to_exec_file (int pid) override;
+
+ bool supports_multifs () override;
+
+ int multifs_open (int pid, const char *filename, int flags,
+ mode_t mode) override;
+
+ int multifs_unlink (int pid, const char *filename) override;
+
+ ssize_t multifs_readlink (int pid, const char *filename, char *buf,
+ size_t bufsiz) override;
+
+ const char *thread_name (ptid_t thread) override;
+
+#if USE_THREAD_DB
+ bool thread_handle (ptid_t ptid, gdb_byte **handle,
+ int *handle_len) override;
+#endif
+
+ bool supports_catch_syscall () override;
+
+ /* Return the information to access registers. This has public
+ visibility because proc-service uses it. */
+ virtual const regs_info *get_regs_info () = 0;
+
+private:
+
+ /* Handle a GNU/Linux extended wait response. If we see a clone,
+ fork, or vfork event, we need to add the new LWP to our list
+ (and return 0 so as not to report the trap to higher layers).
+ If we see an exec event, we will modify ORIG_EVENT_LWP to point
+ to a new LWP representing the new program. */
+ int handle_extended_wait (lwp_info **orig_event_lwp, int wstat);
+
+ /* Do low-level handling of the event, and check if this is an event we want
+ to report. Is so, store it as a pending status in the lwp_info structure
+ corresponding to LWPID. */
+ void filter_event (int lwpid, int wstat);
+
+ /* Wait for an event from child(ren) WAIT_PTID, and return any that
+ match FILTER_PTID (leaving others pending). The PTIDs can be:
+ minus_one_ptid, to specify any child; a pid PTID, specifying all
+ lwps of a thread group; or a PTID representing a single lwp. Store
+ the stop status through the status pointer WSTAT. OPTIONS is
+ passed to the waitpid call. Return 0 if no event was found and
+ OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
+ was found. Return the PID of the stopped child otherwise. */
+ int wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
+ int *wstatp, int options);
+
+ /* Wait for an event from child(ren) PTID. PTIDs can be:
+ minus_one_ptid, to specify any child; a pid PTID, specifying all
+ lwps of a thread group; or a PTID representing a single lwp. Store
+ the stop status through the status pointer WSTAT. OPTIONS is
+ passed to the waitpid call. Return 0 if no event was found and
+ OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
+ was found. Return the PID of the stopped child otherwise. */
+ int wait_for_event (ptid_t ptid, int *wstatp, int options);
+
+ /* Wait for all children to stop for the SIGSTOPs we just queued. */
+ void wait_for_sigstop ();
+
+ /* Wait for process, returns status. */
+ ptid_t wait_1 (ptid_t ptid, target_waitstatus *ourstatus,
+ target_wait_flags target_options);
+
+ /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
+ If SUSPEND, then also increase the suspend count of every LWP,
+ except EXCEPT. */
+ void stop_all_lwps (int suspend, lwp_info *except);
+
+ /* Stopped LWPs that the client wanted to be running, that don't have
+ pending statuses, are set to run again, except for EXCEPT, if not
+ NULL. This undoes a stop_all_lwps call. */
+ void unstop_all_lwps (int unsuspend, lwp_info *except);
+
+ /* Start a step-over operation on LWP. When LWP stopped at a
+ breakpoint, to make progress, we need to remove the breakpoint out
+ of the way. If we let other threads run while we do that, they may
+ pass by the breakpoint location and miss hitting it. To avoid
+ that, a step-over momentarily stops all threads while LWP is
+ single-stepped by either hardware or software while the breakpoint
+ is temporarily uninserted from the inferior. When the single-step
+ finishes, we reinsert the breakpoint, and let all threads that are
+ supposed to be running, run again. */
+ void start_step_over (lwp_info *lwp);
+
+ /* If there's a step over in progress, wait until all threads stop
+ (that is, until the stepping thread finishes its step), and
+ unsuspend all lwps. The stepping thread ends with its status
+ pending, which is processed later when we get back to processing
+ events. */
+ void complete_ongoing_step_over ();
+
+ /* Finish a step-over. Reinsert the breakpoint we had uninserted in
+ start_step_over, if still there, and delete any single-step
+ breakpoints we've set, on non hardware single-step targets.
+ Return true if step over finished. */
+ bool finish_step_over (lwp_info *lwp);
+
+ /* When we finish a step-over, set threads running again. If there's
+ another thread that may need a step-over, now's the time to start
+ it. Eventually, we'll move all threads past their breakpoints. */
+ void proceed_all_lwps ();
+
+ /* The reason we resume in the caller, is because we want to be able
+ to pass lwp->status_pending as WSTAT, and we need to clear
+ status_pending_p before resuming, otherwise, resume_one_lwp
+ refuses to resume. */
+ bool maybe_move_out_of_jump_pad (lwp_info *lwp, int *wstat);
+
+ /* Move THREAD out of the jump pad. */
+ void move_out_of_jump_pad (thread_info *thread);
+
+ /* Call low_arch_setup on THREAD. */
+ void arch_setup_thread (thread_info *thread);
+
+#ifdef HAVE_LINUX_USRREGS
+ /* Fetch one register. */
+ void fetch_register (const usrregs_info *usrregs, regcache *regcache,
+ int regno);
+
+ /* Store one register. */
+ void store_register (const usrregs_info *usrregs, regcache *regcache,
+ int regno);
+#endif
+
+ /* Fetch all registers, or just one, from the child process.
+ If REGNO is -1, do this for all registers, skipping any that are
+ assumed to have been retrieved by regsets_fetch_inferior_registers,
+ unless ALL is non-zero.
+ Otherwise, REGNO specifies which register (so we can save time). */
+ void usr_fetch_inferior_registers (const regs_info *regs_info,
+ regcache *regcache, int regno, int all);
+
+ /* Store our register values back into the inferior.
+ If REGNO is -1, do this for all registers, skipping any that are
+ assumed to have been saved by regsets_store_inferior_registers,
+ unless ALL is non-zero.
+ Otherwise, REGNO specifies which register (so we can save time). */
+ void usr_store_inferior_registers (const regs_info *regs_info,
+ regcache *regcache, int regno, int all);
+
+ /* Return the PC as read from the regcache of LWP, without any
+ adjustment. */
+ CORE_ADDR get_pc (lwp_info *lwp);
+
+ /* Called when the LWP stopped for a signal/trap. If it stopped for a
+ trap check what caused it (breakpoint, watchpoint, trace, etc.),
+ and save the result in the LWP's stop_reason field. If it stopped
+ for a breakpoint, decrement the PC if necessary on the lwp's
+ architecture. Returns true if we now have the LWP's stop PC. */
+ bool save_stop_reason (lwp_info *lwp);
+
+ /* Resume execution of LWP. If STEP is nonzero, single-step it. If
+ SIGNAL is nonzero, give it that signal. */
+ void resume_one_lwp_throw (lwp_info *lwp, int step, int signal,
+ siginfo_t *info);
+
+ /* Like resume_one_lwp_throw, but no error is thrown if the LWP
+ disappears while we try to resume it. */
+ void resume_one_lwp (lwp_info *lwp, int step, int signal, siginfo_t *info);
+
+ /* This function is called once per thread. We check the thread's
+ last resume request, which will tell us whether to resume, step, or
+ leave the thread stopped. Any signal the client requested to be
+ delivered has already been enqueued at this point.
+
+ If any thread that GDB wants running is stopped at an internal
+ breakpoint that needs stepping over, we start a step-over operation
+ on that particular thread, and leave all others stopped. */
+ void proceed_one_lwp (thread_info *thread, lwp_info *except);
+
+ /* This function is called once per thread. We check the thread's
+ resume request, which will tell us whether to resume, step, or
+ leave the thread stopped; and what signal, if any, it should be
+ sent.
+
+ For threads which we aren't explicitly told otherwise, we preserve
+ the stepping flag; this is used for stepping over gdbserver-placed
+ breakpoints.
+
+ If pending_flags was set in any thread, we queue any needed
+ signals, since we won't actually resume. We already have a pending
+ event to report, so we don't need to preserve any step requests;
+ they should be re-issued if necessary. */
+ void resume_one_thread (thread_info *thread, bool leave_all_stopped);
+
+ /* Return true if this lwp has an interesting status pending. */
+ bool status_pending_p_callback (thread_info *thread, ptid_t ptid);
+
+ /* Resume LWPs that are currently stopped without any pending status
+ to report, but are resumed from the core's perspective. */
+ void resume_stopped_resumed_lwps (thread_info *thread);
+
+ /* Unsuspend THREAD, except EXCEPT, and proceed. */
+ void unsuspend_and_proceed_one_lwp (thread_info *thread, lwp_info *except);
+
+ /* Return true if this lwp still has an interesting status pending.
+ If not (e.g., it had stopped for a breakpoint that is gone), return
+ false. */
+ bool thread_still_has_status_pending (thread_info *thread);
+
+ /* Return true if this lwp is to-be-resumed and has an interesting
+ status pending. */
+ bool resume_status_pending (thread_info *thread);
+
+ /* Return true if this lwp that GDB wants running is stopped at an
+ internal breakpoint that we need to step over. It assumes that
+ any required STOP_PC adjustment has already been propagated to
+ the inferior's regcache. */
+ bool thread_needs_step_over (thread_info *thread);
+
+ /* Single step via hardware or software single step.
+ Return 1 if hardware single stepping, 0 if software single stepping
+ or can't single step. */
+ int single_step (lwp_info* lwp);
+
+ /* Return true if THREAD is doing hardware single step. */
+ bool maybe_hw_step (thread_info *thread);
+
+ /* Install breakpoints for software single stepping. */
+ void install_software_single_step_breakpoints (lwp_info *lwp);
+
+ /* Fetch the possibly triggered data watchpoint info and store it in
+ CHILD.
+
+ On some archs, like x86, that use debug registers to set
+ watchpoints, it's possible that the way to know which watched
+ address trapped, is to check the register that is used to select
+ which address to watch. Problem is, between setting the watchpoint
+ and reading back which data address trapped, the user may change
+ the set of watchpoints, and, as a consequence, GDB changes the
+ debug registers in the inferior. To avoid reading back a stale
+ stopped-data-address when that happens, we cache in LP the fact
+ that a watchpoint trapped, and the corresponding data address, as
+ soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
+ registers meanwhile, we have the cached data we can rely on. */
+ bool check_stopped_by_watchpoint (lwp_info *child);
+
+ /* Convert a native/host siginfo object, into/from the siginfo in the
+ layout of the inferiors' architecture. */
+ void siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo,
+ int direction);
+
+ /* Add a process to the common process list, and set its private
+ data. */
+ process_info *add_linux_process (int pid, int attached);
+
+ /* Add a new thread. */
+ lwp_info *add_lwp (ptid_t ptid);
+
+ /* Delete a thread. */
+ void delete_lwp (lwp_info *lwp);
+
+public: /* Make this public because it's used from outside. */
+ /* Attach to an inferior process. Returns 0 on success, ERRNO on
+ error. */
+ int attach_lwp (ptid_t ptid);
+
+private: /* Back to private. */
+ /* Detach from LWP. */
+ void detach_one_lwp (lwp_info *lwp);
+
+ /* Detect zombie thread group leaders, and "exit" them. We can't
+ reap their exits until all other threads in the group have
+ exited. */
+ void check_zombie_leaders ();
+
+ /* Convenience function that is called when the kernel reports an exit
+ event. This decides whether to report the event to GDB as a
+ process exit event, a thread exit event, or to suppress the
+ event. */
+ ptid_t filter_exit_event (lwp_info *event_child,
+ target_waitstatus *ourstatus);
+
+ /* Returns true if THREAD is stopped in a jump pad, and we can't
+ move it out, because we need to report the stop event to GDB. For
+ example, if the user puts a breakpoint in the jump pad, it's
+ because she wants to debug it. */
+ bool stuck_in_jump_pad (thread_info *thread);
+
+ /* Convenience wrapper. Returns information about LWP's fast tracepoint
+ collection status. */
+ fast_tpoint_collect_result linux_fast_tracepoint_collecting
+ (lwp_info *lwp, fast_tpoint_collect_status *status);
+
+ /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
+ Fill *SYSNO with the syscall nr trapped. */
+ void get_syscall_trapinfo (lwp_info *lwp, int *sysno);
+
+ /* Returns true if GDB is interested in the event_child syscall.
+ Only to be called when stopped reason is SYSCALL_SIGTRAP. */
+ bool gdb_catch_this_syscall (lwp_info *event_child);
+
+protected:
+ /* The architecture-specific "low" methods are listed below. */
+
+ /* Architecture-specific setup for the current thread. */
+ virtual void low_arch_setup () = 0;
+
+ /* Return false if we can fetch/store the register, true if we cannot
+ fetch/store the register. */
+ virtual bool low_cannot_fetch_register (int regno) = 0;
+
+ virtual bool low_cannot_store_register (int regno) = 0;
+
+ /* Hook to fetch a register in some non-standard way. Used for
+ example by backends that have read-only registers with hardcoded
+ values (e.g., IA64's gr0/fr0/fr1). Returns true if register
+ REGNO was supplied, false if not, and we should fallback to the
+ standard ptrace methods. */
+ virtual bool low_fetch_register (regcache *regcache, int regno);
+
+ /* Return true if breakpoints are supported. Such targets must
+ implement the GET_PC and SET_PC methods. */
+ virtual bool low_supports_breakpoints ();
+
+ virtual CORE_ADDR low_get_pc (regcache *regcache);
+
+ virtual void low_set_pc (regcache *regcache, CORE_ADDR newpc);
+
+ /* Find the next possible PCs after the current instruction executes.
+ Targets that override this method should also override
+ 'supports_software_single_step' to return true. */
+ virtual std::vector<CORE_ADDR> low_get_next_pcs (regcache *regcache);
+
+ /* Return true if there is a breakpoint at PC. */
+ virtual bool low_breakpoint_at (CORE_ADDR pc) = 0;
+
+ /* Breakpoint and watchpoint related functions. See target.h for
+ comments. */
+ virtual int low_insert_point (raw_bkpt_type type, CORE_ADDR addr,
+ int size, raw_breakpoint *bp);
+
+ virtual int low_remove_point (raw_bkpt_type type, CORE_ADDR addr,
+ int size, raw_breakpoint *bp);
+
+ virtual bool low_stopped_by_watchpoint ();
+
+ virtual CORE_ADDR low_stopped_data_address ();
+
+ /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
+ for registers smaller than an xfer unit). */
+ virtual void low_collect_ptrace_register (regcache *regcache, int regno,
+ char *buf);
+
+ virtual void low_supply_ptrace_register (regcache *regcache, int regno,
+ const char *buf);
+
+ /* Hook to convert from target format to ptrace format and back.
+ Returns true if any conversion was done; false otherwise.
+ If DIRECTION is 1, then copy from INF to NATIVE.
+ If DIRECTION is 0, copy from NATIVE to INF. */
+ virtual bool low_siginfo_fixup (siginfo_t *native, gdb_byte *inf,
+ int direction);
+
+ /* Hook to call when a new process is created or attached to.
+ If extra per-process architecture-specific data is needed,
+ allocate it here. */
+ virtual arch_process_info *low_new_process ();
+
+ /* Hook to call when a process is being deleted. If extra per-process
+ architecture-specific data is needed, delete it here. */
+ virtual void low_delete_process (arch_process_info *info);
+
+ /* Hook to call when a new thread is detected.
+ If extra per-thread architecture-specific data is needed,
+ allocate it here. */
+ virtual void low_new_thread (lwp_info *);
+
+ /* Hook to call when a thread is being deleted. If extra per-thread
+ architecture-specific data is needed, delete it here. */
+ virtual void low_delete_thread (arch_lwp_info *);
+
+ /* Hook to call, if any, when a new fork is attached. */
+ virtual void low_new_fork (process_info *parent, process_info *child);
+
+ /* Hook to call prior to resuming a thread. */
+ virtual void low_prepare_to_resume (lwp_info *lwp);
+
+ /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
+ success, -1 on failure. */
+ virtual int low_get_thread_area (int lwpid, CORE_ADDR *addrp);
+
+ /* Returns true if the low target supports range stepping. */
+ virtual bool low_supports_range_stepping ();
+
+ /* Return true if the target supports catch syscall. Such targets
+ override the low_get_syscall_trapinfo method below. */
+ virtual bool low_supports_catch_syscall ();
+
+ /* Fill *SYSNO with the syscall nr trapped. Only to be called when
+ inferior is stopped due to SYSCALL_SIGTRAP. */
+ virtual void low_get_syscall_trapinfo (regcache *regcache, int *sysno);
+
+ /* How many bytes the PC should be decremented after a break. */
+ virtual int low_decr_pc_after_break ();
};
+extern linux_process_target *the_linux_target;
+
#define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
#define get_lwp_thread(lwp) ((lwp)->thread)
+/* Information about a signal that is to be delivered to a thread. */
+
+struct pending_signal
+{
+ pending_signal (int signal)
+ : signal {signal}
+ {};
+
+ int signal;
+ siginfo_t info;
+};
+
/* This struct is recorded in the target_data field of struct thread_info.
On linux ``all_threads'' is keyed by the LWP ID, which we use as the
struct lwp_info
{
/* Backlink to the parent object. */
- struct thread_info *thread;
+ struct thread_info *thread = nullptr;
/* If this flag is set, the next SIGSTOP will be ignored (the
process will be immediately resumed). This means that either we
(so the SIGSTOP is still pending), or that we stopped the
inferior implicitly via PTRACE_ATTACH and have not waited for it
yet. */
- int stop_expected;
+ int stop_expected = 0;
/* When this is true, we shall not try to resume this thread, even
if last_resume_kind isn't resume_stop. */
- int suspended;
+ int suspended = 0;
/* If this flag is set, the lwp is known to be stopped right now (stop
event already received in a wait()). */
- int stopped;
+ int stopped = 0;
/* Signal whether we are in a SYSCALL_ENTRY or
in a SYSCALL_RETURN event.
Values:
- TARGET_WAITKIND_SYSCALL_ENTRY
- TARGET_WAITKIND_SYSCALL_RETURN */
- enum target_waitkind syscall_state;
+ enum target_waitkind syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
/* When stopped is set, the last wait status recorded for this lwp. */
- int last_status;
+ int last_status = 0;
/* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
this LWP's last event, to pass to GDB without any further
the parent fork event is not reported to higher layers. Used to
avoid wildcard vCont actions resuming a fork child before GDB is
notified about the parent's fork event. */
- struct lwp_info *fork_relative;
+ struct lwp_info *fork_relative = nullptr;
/* When stopped is set, this is where the lwp last stopped, with
decr_pc_after_break already accounted for. If the LWP is
running, this is the address at which the lwp was resumed. */
- CORE_ADDR stop_pc;
+ CORE_ADDR stop_pc = 0;
/* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
been reported. */
- int status_pending_p;
- int status_pending;
+ int status_pending_p = 0;
+ int status_pending = 0;
/* The reason the LWP last stopped, if we need to track it
(breakpoint, watchpoint, etc.) */
- enum target_stop_reason stop_reason;
+ enum target_stop_reason stop_reason = TARGET_STOPPED_BY_NO_REASON;
/* On architectures where it is possible to know the data address of
a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
contains such data address. Only valid if STOPPED_BY_WATCHPOINT
is true. */
- CORE_ADDR stopped_data_address;
+ CORE_ADDR stopped_data_address = 0;
/* If this is non-zero, it is a breakpoint to be reinserted at our next
stop (SIGTRAP stops only). */
- CORE_ADDR bp_reinsert;
+ CORE_ADDR bp_reinsert = 0;
/* If this flag is set, the last continue operation at the ptrace
level on this process was a single-step. */
- int stepping;
+ int stepping = 0;
/* Range to single step within. This is a copy of the step range
passed along the last resume request. See 'struct
thread_resume'. */
- CORE_ADDR step_range_start; /* Inclusive */
- CORE_ADDR step_range_end; /* Exclusive */
+ CORE_ADDR step_range_start = 0; /* Inclusive */
+ CORE_ADDR step_range_end = 0; /* Exclusive */
/* If this flag is set, we need to set the event request flags the
next time we see this LWP stop. */
- int must_set_ptrace_flags;
+ int must_set_ptrace_flags = 0;
- /* If this is non-zero, it points to a chain of signals which need to
- be delivered to this process. */
- struct pending_signals *pending_signals;
+ /* A chain of signals that need to be delivered to this process. */
+ std::list<pending_signal> pending_signals;
/* A link used when resuming. It is initialized from the resume request,
and then processed and cleared in linux_resume_one_lwp. */
- struct thread_resume *resume;
+ struct thread_resume *resume = nullptr;
/* Information bout this lwp's fast tracepoint collection status (is it
currently stopped in the jump pad, and if so, before or at/after the
relocated instruction). Normally, we won't care about this, but we will
if a signal arrives to this lwp while it is collecting. */
- fast_tpoint_collect_result collecting_fast_tracepoint;
+ fast_tpoint_collect_result collecting_fast_tracepoint
+ = fast_tpoint_collect_result::not_collecting;
- /* If this is non-zero, it points to a chain of signals which need
- to be reported to GDB. These were deferred because the thread
- was doing a fast tracepoint collect when they arrived. */
- struct pending_signals *pending_signals_to_report;
+ /* A chain of signals that need to be reported to GDB. These were
+ deferred because the thread was doing a fast tracepoint collect
+ when they arrived. */
+ std::list<pending_signal> pending_signals_to_report;
/* When collecting_fast_tracepoint is first found to be 1, we insert
a exit-jump-pad-quickly breakpoint. This is it. */
- struct breakpoint *exit_jump_pad_bkpt;
+ struct breakpoint *exit_jump_pad_bkpt = nullptr;
#ifdef USE_THREAD_DB
- int thread_known;
+ int thread_known = 0;
/* The thread handle, used for e.g. TLS access. Only valid if
THREAD_KNOWN is set. */
- td_thrhandle_t th;
+ td_thrhandle_t th {};
/* The pthread_t handle. */
- thread_t thread_handle;
+ thread_t thread_handle {};
#endif
/* Arch-specific additions. */
- struct arch_lwp_info *arch_private;
+ struct arch_lwp_info *arch_private = nullptr;
};
int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);