old-cross-binutils/gdb/doc/observer.texi
Pedro Alves 6c95b8df7f 2009-10-19 Pedro Alves <pedro@codesourcery.com>
Stan Shebs	<stan@codesourcery.com>

	Add base multi-executable/process support to GDB.

	gdb/
	* Makefile.in (SFILES): Add progspace.c.
	(COMMON_OBS): Add progspace.o.
	* progspace.h: New.
	* progspace.c: New.

	* breakpoint.h (struct bp_target_info) <placed_address_space>: New
	field.
	(struct bp_location) <pspace>: New field.
	(struct breakpoint) <pspace>: New field.
	(bpstat_stop_status, breakpoint_here_p)
	(moribund_breakpoint_here_p, breakpoint_inserted_here_p)
	(regular_breakpoint_inserted_here_p)
	(software_breakpoint_inserted_here_p, breakpoint_thread_match)
	(set_default_breakpoint): Adjust prototypes.
	(remove_breakpoints_pid, breakpoint_program_space_exit): Declare.
	(insert_single_step_breakpoint, deprecated_insert_raw_breakpoint):
	Adjust prototypes.
	* breakpoint.c (executing_startup): Delete.
	(default_breakpoint_sspace): New.
	(breakpoint_restore_shadows): Skip if the address space doesn't
	match.
	(update_watchpoint): Record the frame's program space in the
	breakpoint location.
	(insert_bp_location): Record the address space in target_info.
	Adjust to pass the symbol space to solib_name_from_address.
	(breakpoint_program_space_exit): New.
	(insert_breakpoint_locations): Switch the symbol space and thread
	when inserting breakpoints.  Don't insert breakpoints in a vfork
	parent waiting for vfork done if we're not attached to the vfork
	child.
	(remove_breakpoints_pid): New.
	(reattach_breakpoints): Switch to a thread of PID.  Ignore
	breakpoints of other symbol spaces.
	(create_internal_breakpoint): Store the symbol space in the sal.
	(create_longjmp_master_breakpoint): Iterate over all symbol
	spaces.
	(update_breakpoints_after_exec): Ignore breakpoints for other
	symbol spaces.
	(remove_breakpoint): Rename to ...
	(remove_breakpoint_1): ... this.  Pass the breakpoints symbol
	space to solib_name_from_address.
	(remove_breakpoint): New.
	(mark_breakpoints_out): Ignore breakpoints from other symbol
	spaces.
	(breakpoint_init_inferior): Ditto.
	(breakpoint_here_p): Add an address space argument and adjust to
	use breakpoint_address_match.
	(moribund_breakpoint_here_p): Ditto.
	(regular_breakpoint_inserted_here_p): Ditto.
	(breakpoint_inserted_here_p): Ditto.
	(software_breakpoint_inserted_here_p): Ditto.
	(breakpoint_thread_match): Ditto.
	(bpstat_check_location): Ditto.
	(bpstat_stop_status): Ditto.
	(print_breakpoint_location): If there's a location to print,
	switch the current symbol space.
	(print_one_breakpoint_location): Add `allflag' argument.
	(print_one_breakpoint): Ditto.	Adjust.
	(do_captured_breakpoint_query): Adjust.
	(breakpoint_1): Adjust.
	(breakpoint_has_pc): Also match the symbol space.
	(describe_other_breakpoints): Add a symbol space argument and
	adjust.
	(set_default_breakpoint): Add a symbol space argument.	Set
	default_breakpoint_sspace.
	(breakpoint_address_match): New.
	(check_duplicates_for): Add an address space argument, and adjust.
	(set_raw_breakpoint): Record the symbol space in the location and
	in the breakpoint.
	(set_longjmp_breakpoint): Skip longjmp master breakpoints from
	other symbol spaces.
	(remove_thread_event_breakpoints, remove_solib_event_breakpoints)
	(disable_breakpoints_in_shlibs): Skip breakpoints from other
	symbol spaces.
	(disable_breakpoints_in_unloaded_shlib): Match symbol spaces.
	(create_catchpoint): Set the symbol space in the sal.
	(disable_breakpoints_before_startup): Skip breakpoints from other
	symbol spaces.	Set executing_startup in the current symbol space.
	(enable_breakpoints_after_startup): Clear executing_startup in the
	current symbol space.  Skip breakpoints from other symbol spaces.
	(clone_momentary_breakpoint): Also copy the symbol space.
	(add_location_to_breakpoint): Set the location's symbol space.
	(bp_loc_is_permanent): Switch thread and symbol space.
	(create_breakpoint): Adjust.
	(expand_line_sal_maybe): Expand comment to mention symbol spaces.
	Switch thread and symbol space when reading memory.
	(parse_breakpoint_sals): Set the symbol space in the sal.
	(break_command_really): Ditto.
	(skip_prologue_sal): Switch and space.
	(resolve_sal_pc): Ditto.
	(watch_command_1): Record the symbol space in the sal.
	(create_ada_exception_breakpoint): Adjust.
	(clear_command): Adjust.  Match symbol spaces.
	(update_global_location_list): Use breakpoint_address_match.
	(breakpoint_re_set_one): Switch thread and space.
	(breakpoint_re_set): Save symbol space.
	(breakpoint_re_set_thread): Also reset the symbol space.
	(deprecated_insert_raw_breakpoint): Add an address space argument.
	Adjust.
	(insert_single_step_breakpoint): Ditto.
	(single_step_breakpoint_inserted_here_p): Ditto.
	(clear_syscall_counts): New.
	(_initialize_breakpoint): Install it as inferior_exit observer.

	* exec.h: Include "progspace.h".
	(exec_bfd, exec_bfd_mtime): New defines.
	(exec_close): Declare.
	* exec.c: Include "gdbthread.h" and "progspace.h".
	(exec_bfd, exec_bfd_mtime, current_target_sections_1): Delete.
	(using_exec_ops): New.
	(exec_close_1): Rename to exec_close, and make public.
	(exec_close): Rename to exec_close_1, and adjust all callers.  Add
	description.  Remove target sections and close executables from
	all program spaces.
	(exec_file_attach): Add comment.
	(add_target_sections): Check on `using_exec_ops' to check if the
	target should be pushed.
	(remove_target_sections): Only unpush the target if there are no
	more target sections in any symbol space.
	* gdbcore.h: Include "exec.h".
	(exec_bfd, exec_bfd_mtime): Remove declarations.

	* frame.h (get_frame_program_space, get_frame_address_space)
	(frame_unwind_program_space): Declare.
	* frame.c (struct frame_info) <pspace, aspace>: New fields.
	(create_sentinel_frame): Add program space argument.  Set the
	pspace and aspace fields of the frame object.
	(get_current_frame, create_new_frame): Adjust.
	(get_frame_program_space): New.
	(frame_unwind_program_space): New.
	(get_frame_address_space): New.
	* stack.c (print_frame_info): Adjust.
	(print_frame): Use the frame's program space.

	* gdbthread.h (any_live_thread_of_process): Declare.
	* thread.c (any_live_thread_of_process): New.
	(switch_to_thread): Switch the program space as well.
	(restore_selected_frame): Don't warn if trying to restore frame
	level 0.

	* inferior.h: Include "progspace.h".
	(detach_fork): Declare.
	(struct inferior) <removable, aspace, pspace>
	<vfork_parent, vfork_child, pending_detach>
	<waiting_for_vfork_done>: New fields.
	<terminal_info>: Remove field.
	<data, num_data>: New fields.
	(register_inferior_data, register_inferior_data_with_cleanup)
	(clear_inferior_data, set_inferior_data, inferior_data): Declare.
	(exit_inferior, exit_inferior_silent, exit_inferior_num_silent)
	(inferior_appeared): Declare.
	(find_inferior_pid): Typo.
	(find_inferior_id, find_inferior_for_program_space): Declare.
	(set_current_inferior, save_current_inferior, prune_inferiors)
	(number_of_inferiors): Declare.
	(inferior_list): Declare.
	* inferior.c: Include "gdbcore.h" and "symfile.h".
	(inferior_list): Make public.
	(delete_inferior_1): Always delete thread silently.
	(find_inferior_id): Make public.
	(current_inferior_): New.
	(current_inferior): Use it.
	(set_current_inferior): New.
	(restore_inferior): New.
	(save_current_inferior): New.
	(free_inferior): Free the per-inferior data.
	(add_inferior_silent): Allocate per-inferior data.
	Call inferior_appeared.
	(delete_threads_of_inferior): New.
	(delete_inferior_1): Adjust interface to take an inferior pointer.
	(delete_inferior): Adjust.
	(delete_inferior_silent): Adjust.
	(exit_inferior_1): New.
	(exit_inferior): New.
	(exit_inferior_silent): New.
	(exit_inferior_num_silent): New.
	(detach_inferior): Adjust.
	(inferior_appeared): New.
	(discard_all_inferiors): Adjust.
	(find_inferior_id): Make public.  Assert pid is not zero.
	(find_inferior_for_program_space): New.
	(have_inferiors): Check if we have any inferior with pid not zero.
	(have_live_inferiors): Go over all pushed targets looking for
	process_stratum.
	(prune_inferiors): New.
	(number_of_inferiors): New.
	(print_inferior): Add executable column.  Print vfork parent/child
	relationships.
	(inferior_command): Adjust to cope with not running inferiors.
	(remove_inferior_command): New.
	(add_inferior_command): New.
	(clone_inferior_command): New.
	(struct inferior_data): New.
	(struct inferior_data_registration): New.
	(struct inferior_data_registry): New.
	(inferior_data_registry): New.
	(register_inferior_data_with_cleanup): New.
	(register_inferior_data): New.
	(inferior_alloc_data): New.
	(inferior_free_data): New.
	(clear_inferior_data): New.
	(set_inferior_data): New.
	(inferior_data): New.
	(initialize_inferiors): New.
	(_initialize_inferiors): Register "add-inferior",
	"remove-inferior" and "clone-inferior" commands.

	* objfiles.h: Include "progspace.h".
	(struct objfile) <pspace>: New field.
	(symfile_objfile, object_files): Don't declare.
	(ALL_PSPACE_OBJFILES): New.
	(ALL_PSPACE_OBJFILES_SAFE): New.
	(ALL_OBJFILES, ALL_OBJFILES_SAFE): Adjust.
	(ALL_PSPACE_SYMTABS): New.
	(ALL_PRIMARY_SYMTABS): Adjust.
	(ALL_PSPACE_PRIMARY_SYMTABS): New.
	(ALL_PSYMTABS): Adjust.
	(ALL_PSPACE_PSYMTABS): New.
	* objfiles.c (object_files, symfile_objfile): Delete.
	(struct objfile_sspace_info): New.
	(objfiles_pspace_data): New.
	(objfiles_pspace_data_cleanup): New.
	(get_objfile_pspace_data): New.
	(objfiles_changed_p): Delete.
	(allocate_objfile): Set the objfile's program space.  Adjust to
	reference objfiles_changed_p in pspace data.
	(free_objfile): Adjust to reference objfiles_changed_p in pspace
	data.
	(objfile_relocate): Ditto.
	(update_section_map): Add pspace argument.  Adjust to iterate over
	objfiles in the passed in pspace.
	(find_pc_section): Delete sections and num_sections statics.
	Adjust to refer to program space's objfiles_changed_p.	Adjust to
	refer to sections and num_sections store in the objfile's pspace
	data.
	(objfiles_changed): Adjust to reference objfiles_changed_p in
	pspace data.
	(_initialize_objfiles): New.
	* linespec.c (decode_all_digits, decode_dollar): Set the sal's
	program space.
	* source.c (current_source_pspace): New.
	(get_current_source_symtab_and_line): Set the sal's program space.
	(set_current_source_symtab_and_line): Set current_source_pspace.
	(select_source_symtab): Ditto.	Use ALL_OBJFILES.
	(forget_cached_source_info): Iterate over all program spaces.
	* symfile.c (clear_symtab_users): Adjust.
	* symmisc.c (print_symbol_bcache_statistics): Iterate over all
	program spaces.
	(print_objfile_statistics): Ditto.
	(maintenance_print_msymbols): Ditto.
	(maintenance_print_objfiles): Ditto.
	(maintenance_info_symtabs): Ditto.
	(maintenance_info_psymtabs): Ditto.
	* symtab.h (SYMTAB_PSPACE): New.
	(struct symtab_and_line) <pspace>: New field.
	* symtab.c (init_sal): Clear the sal's program space.
	(find_pc_sect_symtab): Set the sal's program space.  Switch thread
	and space.
	(append_expanded_sal): Add program space argument.  Iterate over
	all program spaces.
	(expand_line_sal): Iterate over all program spaces.  Switch
	program space.

	* target.h (enum target_waitkind) <TARGET_WAITKIND_VFORK_DONE>: New.
	(struct target_ops) <to_thread_address_space>: New field.
	(target_thread_address_space): Define.
	* target.c (target_detach): Only remove breakpoints from the
	inferior we're detaching.
	(target_thread_address_space): New.

	* defs.h (initialize_progspace): Declare.
	* top.c (gdb_init): Call it.

	* solist.h (struct so_list) <sspace>: New field.
	* solib.h (struct program_space): Forward declare.
	(solib_name_from_address): Adjust prototype.
	* solib.c (so_list_head): Replace with a macro referencing the
	program space.
	(update_solib_list): Set the so's program space.
	(solib_name_from_address): Add a program space argument and adjust.

	* solib-svr4.c (struct svr4_info) <pid>: Delete field.
	<interp_text_sect_low, interp_text_sect_high, interp_plt_sect_low>
	<interp_plt_sect_high>: New fields.
	(svr4_info_p, svr4_info): Delete.
	(solib_svr4_sspace_data): New.
	(get_svr4_info): Rewrite.
	(svr4_sspace_data_cleanup): New.
	(open_symbol_file_object): Adjust.
	(svr4_default_sos): Adjust.
	(svr4_fetch_objfile_link_map): Adjust.
	(interp_text_sect_low, interp_text_sect_high, interp_plt_sect_low)
	(interp_plt_sect_high): Delete.
	(svr4_in_dynsym_resolve_code): Adjust.
	(enable_break): Adjust.
	(svr4_clear_solib): Revert bit that removed the svr4_info here,
	and reinstate clearing debug_base, debug_loader_offset_p,
	debug_loader_offset and debug_loader_name.
	(_initialize_svr4_solib): Register solib_svr4_pspace_data.  Don't
	install an inferior_exit observer anymore.

	* printcmd.c (struct display) <pspace>: New field.
	(display_command): Set the display's sspace.
	(do_one_display): Match the display's sspace.
	(display_uses_solib_p): Ditto.

	* linux-fork.c (detach_fork): Moved to infrun.c.
	(_initialize_linux_fork): Moved "detach-on-fork" command to
	infrun.c.
	* infrun.c (detach_fork): Moved from linux-fork.c.
	(proceed_after_vfork_done): New.
	(handle_vfork_child_exec_or_exit): New.
	(follow_exec_mode_replace, follow_exec_mode_keep)
	(follow_exec_mode_names, follow_exec_mode_string)
	(show_follow_exec_mode_string): New.
	(follow_exec): New.  Reinstate the mark_breakpoints_out call.
	Remove shared libraries before attaching new executable.  If user
	wants to keep the inferior, keep it.
	(displaced_step_fixup): Adjust to pass an address space to the
	breakpoints module.
	(resume): Ditto.
	(clear_proceed_status): In all-stop mode, always clear the proceed
	status of all threads.
	(prepare_to_proceed): Adjust to pass an address space to the
	breakpoints module.
	(proceed): Ditto.
	(adjust_pc_after_break): Ditto.
	(handle_inferior_event): When handling a process exit, switch the
	program space to the inferior's that had exited.  Call
	handle_vfork_child_exec_or_exit.  Adjust to pass an address space
	to the breakpoints module.  In non-stop mode, when following a
	fork and detach-fork is off, also resume the other branch.  Handle
	TARGET_WAITKIND_VFORK_DONE.  Set the program space in sals.
	(normal_stop): Prune inferiors.
	(_initialize_infrun): Install the new "follow-exec-mode" command.
	"detach-on-fork" moved here.

	* regcache.h (get_regcache_aspace): Declare.
	* regcache.c (struct regcache) <aspace>: New field.
	(regcache_xmalloc): Clear the aspace.
	(get_regcache_aspace): New.
	(regcache_cpy): Copy the aspace field.
	(regcache_cpy_no_passthrough): Ditto.
	(get_thread_regcache): Fetch the thread's address space from the
	target, and store it in the regcache.

	* infcall.c (call_function_by_hand): Set the sal's pspace.

	* arch-utils.c (default_has_shared_address_space): New.
	* arch-utils.h (default_has_shared_address_space): Declare.

	* gdbarch.sh (has_shared_address_space): New.
	* gdbarch.h, gdbarch.c: Regenerate.

	* linux-tdep.c: Include auxv.h, target.h, elf/common.h.
	(linux_has_shared_address_space): New.
	(_initialize_linux_tdep): Declare.

	* arm-tdep.c (arm_software_single_step): Pass the frame's address
	space to insert_single_step_breakpoint.
	* arm-linux-tdep.c (arm_linux_software_single_step): Pass the
	frame's pspace to breakpoint functions.
	* cris-tdep.c (crisv32_single_step_through_delay): Ditto.
	(cris_software_single_step): Ditto.
	* mips-tdep.c (deal_with_atomic_sequence): Add frame argument.
	Pass the frame's pspace to breakpoint functions.
	(mips_software_single_step): Adjust.
	(mips_single_step_through_delay): Adjust.
	* rs6000-aix-tdep.c (rs6000_software_single_step): Adjust.
	* rs6000-tdep.c (ppc_deal_with_atomic_sequence): Adjust.
	* solib-irix.c (enable_break): Adjust to pass the current frame's
	address space to breakpoint functions.
	* sparc-tdep.c (sparc_software_single_step): Ditto.
	* spu-tdep.c (spu_software_single_step): Ditto.
	* alpha-tdep.c (alpha_software_single_step): Ditto.
	* record.c (record_wait): Adjust to pass an address space to the
	breakpoints module.

	* fork-child.c (fork_inferior): Set the new inferior's program and
	address spaces.
	* inf-ptrace.c (inf_ptrace_follow_fork): Copy the parent's program
	and address spaces.
	(inf_ptrace_attach): Set the inferior's program and address spaces.
	* linux-nat.c: Include "solib.h".
	(linux_child_follow_fork): Manage parent and child's program and
	address spaces.	 Clone the parent's program space if necessary.
	Don't wait for the vfork to be done here.  Refuse to resume if
	following the vfork parent while leaving the child stopped.
	(resume_callback): Don't resume a vfork parent.
	(linux_nat_resume): Also check for pending events in the
	lp->waitstatus field.
	(linux_handle_extended_wait): Report TARGET_WAITKIND_VFORK_DONE
	events to the core.
	(stop_wait_callback): Don't wait for SIGSTOP on vfork parents.
	(cancel_breakpoint): Adjust.
	* linux-thread-db.c (thread_db_wait): Don't remove thread event
	breakpoints here.
	(thread_db_mourn_inferior): Don't mark breakpoints out here.
	Remove thread event breakpoints after mourning.
	* corelow.c: Include progspace.h.
	(core_open): Set the inferior's program and address spaces.
	* remote.c (remote_add_inferior): Set the new inferior's program
	and address spaces.
	(remote_start_remote): Update address spaces.
	(extended_remote_create_inferior_1): Don't init the thread list if
	we already debugging other inferiors.
	* darwin-nat.c (darwin_attach): Set the new inferior's program and
	address spaces.
	* gnu-nat.c (gnu_attach): Ditto.
	* go32-nat.c (go32_create_inferior): Ditto.
	* inf-ttrace.c (inf_ttrace_follow_fork, inf_ttrace_attach): Ditto.
	* monitor.c (monitor_open): Ditto.
	* nto-procfs.c (procfs_attach, procfs_create_inferior): Ditto.
	* procfs.c (do_attach): Ditto.
	* windows-nat.c (do_initial_windows_stuff): Ditto.

	* inflow.c (inferior_process_group)
	(terminal_init_inferior_with_pgrp, terminal_inferior,
	(terminal_ours_1, inflow_inferior_exit, copy_terminal_info)
	(child_terminal_info, new_tty_postfork, set_sigint_trap): Adjust
	to use per-inferior data instead of inferior->terminal_info.
	(inflow_inferior_data): New.
	(inflow_new_inferior): Delete.
	(inflow_inferior_data_cleanup): New.
	(get_inflow_inferior_data): New.

	* mi/mi-interp.c (mi_new_inferior): Rename to...
	(mi_inferior_appeared): ... this.
	(mi_interpreter_init): Adjust.

	* tui/tui-disasm.c: Include "progspace.h".
	(tui_set_disassem_content): Pass an address space to
	breakpoint_here_p.

	* NEWS: Mention multi-program debugging support.  Mention new
	commands "add-inferior", "clone-inferior", "remove-inferior",
	"maint info program-spaces", and new option "set
	follow-exec-mode".

2009-10-19  Pedro Alves	 <pedro@codesourcery.com>
	    Stan Shebs	<stan@codesourcery.com>

	gdb/doc/
	* observer.texi (new_inferior): Rename to...
	(inferior_appeared): ... this.

2009-10-19  Pedro Alves	 <pedro@codesourcery.com>
	    Stan Shebs	<stan@codesourcery.com>

	gdb/testsuite/
	* gdb.base/foll-vfork.exp: Adjust to spell out "follow-fork".
	* gdb.base/foll-exec.exp: Adjust to expect a process id before
	"Executing new program".
	* gdb.base/foll-fork.exp: Adjust to spell out "follow-fork".
	* gdb.base/multi-forks.exp: Ditto.  Adjust to the inferior being
	left listed after having been killed.
	* gdb.base/attach.exp: Adjust to spell out "symbol-file".
	* gdb.base/maint.exp: Adjust test.

	* Makefile.in (ALL_SUBDIRS): Add gdb.multi.
	* gdb.multi/Makefile.in: New.
	* gdb.multi/base.exp: New.
	* gdb.multi/goodbye.c: New.
	* gdb.multi/hangout.c: New.
	* gdb.multi/hello.c: New.
	* gdb.multi/bkpt-multi-exec.c: New.
	* gdb.multi/bkpt-multi-exec.exp: New.
	* gdb.multi/crashme.c: New.

2009-10-19  Pedro Alves	 <pedro@codesourcery.com>
	    Stan Shebs	<stan@codesourcery.com>

	gdb/doc/
	* gdb.texinfo (Inferiors): Rename node to ...
	(Inferiors and Programs): ... this.  Mention running multiple
	programs in the same debug session.
	<info inferiors>: Mention the new 'Executable' column if "info
	inferiors".  Update examples.  Document the "add-inferior",
	"clone-inferior", "remove-inferior" and "maint info
	program-spaces" commands.
	(Process): Rename node to...
	(Forks): ... this.  Document "set|show follow-exec-mode".
2009-10-19 09:51:43 +00:00

215 lines
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Text

@c -*-texinfo-*-
@c This file is part of the GDB manual.
@c
@c Copyright (C) 2003, 2004, 2005, 2006, 2008
@c Free Software Foundation, Inc.
@c
@c See the file gdbint.texinfo for copying conditions.
@c
@c Also, the @deftypefun lines from this file are processed into a
@c header file during the GDB build process. Permission is granted
@c to redistribute and/or modify those lines under the terms of the
@c GNU General Public License as published by the Free Software
@c Foundation; either version 2 of the License, or (at your option)
@c any later version.
@node GDB Observers
@appendix @value{GDBN} Currently available observers
@section Implementation rationale
@cindex observers implementation rationale
An @dfn{observer} is an entity which is interested in being notified
when GDB reaches certain states, or certain events occur in GDB.
The entity being observed is called the @dfn{subject}. To receive
notifications, the observer attaches a callback to the subject.
One subject can have several observers.
@file{observer.c} implements an internal generic low-level event
notification mechanism. This generic event notification mechanism is
then re-used to implement the exported high-level notification
management routines for all possible notifications.
The current implementation of the generic observer provides support
for contextual data. This contextual data is given to the subject
when attaching the callback. In return, the subject will provide
this contextual data back to the observer as a parameter of the
callback.
Note that the current support for the contextual data is only partial,
as it lacks a mechanism that would deallocate this data when the
callback is detached. This is not a problem so far, as this contextual
data is only used internally to hold a function pointer. Later on, if
a certain observer needs to provide support for user-level contextual
data, then the generic notification mechanism will need to be
enhanced to allow the observer to provide a routine to deallocate the
data when attaching the callback.
The observer implementation is also currently not reentrant.
In particular, it is therefore not possible to call the attach
or detach routines during a notification.
@section Debugging
Observer notifications can be traced using the command @samp{set debug
observer 1} (@pxref{Debugging Output, , Optional messages about
internal happenings, gdb, Debugging with @var{GDBN}}).
@section @code{normal_stop} Notifications
@cindex @code{normal_stop} observer
@cindex notification about inferior execution stop
@value{GDBN} notifies all @code{normal_stop} observers when the
inferior execution has just stopped, the associated messages and
annotations have been printed, and the control is about to be returned
to the user.
Note that the @code{normal_stop} notification is not emitted when
the execution stops due to a breakpoint, and this breakpoint has
a condition that is not met. If the breakpoint has any associated
commands list, the commands are executed after the notification
is emitted.
The following interfaces are available to manage observers:
@deftypefun extern struct observer *observer_attach_@var{event} (observer_@var{event}_ftype *@var{f})
Using the function @var{f}, create an observer that is notified when
ever @var{event} occurs, return the observer.
@end deftypefun
@deftypefun extern void observer_detach_@var{event} (struct observer *@var{observer});
Remove @var{observer} from the list of observers to be notified when
@var{event} occurs.
@end deftypefun
@deftypefun extern void observer_notify_@var{event} (void);
Send a notification to all @var{event} observers.
@end deftypefun
The following observable events are defined:
@deftypefun void normal_stop (struct bpstats *@var{bs}, int @var{print_frame})
The inferior has stopped for real. The @var{bs} argument describes
the breakpoints were are stopped at, if any. Second argument
@var{print_frame} non-zero means display the location where the
inferior has stopped.
@end deftypefun
@deftypefun void target_changed (struct target_ops *@var{target})
The target's register contents have changed.
@end deftypefun
@deftypefun void executable_changed (void)
The executable being debugged by GDB has changed: The user decided
to debug a different program, or the program he was debugging has
been modified since being loaded by the debugger (by being recompiled,
for instance).
@end deftypefun
@deftypefun void inferior_created (struct target_ops *@var{objfile}, int @var{from_tty})
@value{GDBN} has just connected to an inferior. For @samp{run},
@value{GDBN} calls this observer while the inferior is still stopped
at the entry-point instruction. For @samp{attach} and @samp{core},
@value{GDBN} calls this observer immediately after connecting to the
inferior, and before any information on the inferior has been printed.
@end deftypefun
@deftypefun void solib_loaded (struct so_list *@var{solib})
The shared library specified by @var{solib} has been loaded. Note that
when @value{GDBN} calls this observer, the library's symbols probably
haven't been loaded yet.
@end deftypefun
@deftypefun void solib_unloaded (struct so_list *@var{solib})
The shared library specified by @var{solib} has been unloaded.
Note that when @value{GDBN} calls this observer, the library's
symbols have not been unloaded yet, and thus are still available.
@end deftypefun
@deftypefun void new_objfile (struct objfile *@var{objfile})
The symbol file specified by @var{objfile} has been loaded.
Called with @var{objfile} equal to @code{NULL} to indicate
previously loaded symbol table data has now been invalidated.
@end deftypefun
@deftypefun void new_thread (struct thread_info *@var{t})
The thread specified by @var{t} has been created.
@end deftypefun
@deftypefun void thread_exit (struct thread_info *@var{t}, int @var{silent})
The thread specified by @var{t} has exited. The @var{silent} argument
indicates that @value{GDBN} is removing the thread from its tables
without wanting to notify the user about it.
@end deftypefun
@deftypefun void thread_stop_requested (ptid_t @var{ptid})
An explicit stop request was issued to @var{ptid}. If @var{ptid}
equals @var{minus_one_ptid}, the request applied to all threads. If
@code{ptid_is_pid(ptid)} returns true, the request applied to all
threads of the process pointed at by @var{ptid}. Otherwise, the
request applied to the single thread pointed at by @var{ptid}.
@end deftypefun
@deftypefun void target_resumed (ptid_t @var{ptid})
The target was resumed. The @var{ptid} parameter specifies which
thread was resume, and may be RESUME_ALL if all threads are resumed.
@end deftypefun
@deftypefun void about_to_proceed (void)
The target is about to be proceeded.
@end deftypefun
@deftypefun void breakpoint_created (int @var{bpnum})
A new breakpoint has been created. The argument @var{bpnum} is the
number of the newly-created breakpoint.
@end deftypefun
@deftypefun void breakpoint_deleted (int @var{bpnum})
A breakpoint has been destroyed. The argument @var{bpnum} is the
number of the newly-destroyed breakpoint.
@end deftypefun
@deftypefun void breakpoint_modified (int @var{bpnum})
A breakpoint has been modified in some way. The argument @var{bpnum}
is the number of the modified breakpoint.
@end deftypefun
@deftypefun void tracepoint_created (int @var{tpnum})
A new tracepoint has been created. The argument @var{tpnum} is the
number of the newly-created tracepoint.
@end deftypefun
@deftypefun void tracepoint_deleted (int @var{tpnum})
A tracepoint has been destroyed. The argument @var{tpnum} is the
number of the newly-destroyed tracepoint.
@end deftypefun
@deftypefun void tracepoint_modified (int @var{tpnum})
A tracepoint has been modified in some way. The argument @var{tpnum}
is the number of the modified tracepoint.
@end deftypefun
@deftypefun void architecture_changed (struct gdbarch *@var{newarch})
The current architecture has changed. The argument @var{newarch} is
a pointer to the new architecture.
@end deftypefun
@deftypefun void thread_ptid_changed (ptid_t @var{old_ptid}, ptid_t @var{new_ptid})
The thread's ptid has changed. The @var{old_ptid} parameter specifies
the old value, and @var{new_ptid} specifies the new value.
@end deftypefun
@deftypefun void inferior_appeared (int @var{pid})
@value{GDBN} has attached to a new inferior identified by @var{pid}.
@end deftypefun
@deftypefun void inferior_exit (int @var{pid})
Either @value{GDBN} detached from the inferior, or the inferior
exited. The argument @var{pid} identifies the inferior.
@end deftypefun
@deftypefun void test_notification (int @var{somearg})
This observer is used for internal testing. Do not use.
See testsuite/gdb.gdb/observer.exp.
@end deftypefun