Introduce show_debug_regs

This commit adds a new global flag show_debug_regs to common-debug.h
to replace the flag debug_hw_points used by gdbserver and by the
Linux x86 and AArch64 ports, and to replace the flag maint_show_dr
used by the Linux MIPS port.

gdb/ChangeLog:

	* common/common-debug.h (show_debug_regs): Declare.
	* common/common-debug.c (show_debug_regs): Define.
	* aarch64-linux-nat.c (debug_hw_points): Don't define.  Replace
	all uses with show_debug_regs.  Replace all uses that considered
	debug_hw_points as a multi-value integer with straight boolean
	uses.
	* x86-nat.c (debug_hw_points): Don't define.  Replace all uses
	with show_debug_regs.
	* nat/x86-dregs.c (debug_hw_points): Don't declare.  Replace
	all uses with show_debug_regs.
	* mips-linux-nat.c (maint_show_dr): Don't define.  Replace all
	uses with show_debug_regs.

gdb/gdbserver/ChangeLog:

	* server.h (debug_hw_points): Don't declare.
	* server.c (debug_hw_points): Don't define.  Replace all uses
	with show_debug_regs.
	* linux-aarch64-low.c (debug_hw_points): Don't define.  Replace
	all uses with show_debug_regs.
Introduce target/target.h

This introduces target/target.h.  This file declares some functions
that the shared code can use and that clients must implement.  It also
changes some shared code to use these functions.

gdb/ChangeLog:

	* target/target.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add target/target.h.
	* target.h: Include target/target.h.
	(target_read_memory, target_write_memory): Don't declare.
	* target.c (target_read_uint32): New function.
	* common/agent.c: Include target/target.h.
	[!GDBSERVER]: Don't include target.h.
	(helper_thread_id): Type changed to uint32_t.
	(agent_get_helper_thread_id): Use target_read_uint32.
	(agent_run_command): Always use target_read_memory and
	target_write_memory.
	(agent_capability): Type changed to uint32_t.
	(agent_capability_check): Use target_read_uint32.

gdb/gdbserver/ChangeLog:

	* target.h: Include target/target.h.
	* target.c (target_read_memory, target_read_uint32)
	(target_write_memory): New functions.
Introduce target_{stop,continue}_ptid

This commit introduces two new functions to stop and restart target
processes that shared code can use and that clients must implement.
It also changes some shared code to use these functions.

gdb/ChangeLog:

	* target/target.h (target_stop_ptid, target_continue_ptid):
	Declare.
	* target.c (target_stop_ptid, target_continue_ptid): New
	functions.
	* common/agent.c [!GDBSERVER]: Don't include infrun.h.
	(agent_run_command): Always use target_stop_ptid and
	target_continue_ptid.

gdb/gdbserver/ChangeLog:

	* target.c (target_stop_ptid, target_continue_ptid): New
	functions.
Introduce target/symbol.h

This introduces target/symbol.h.  This file declares a function that
the shared code can use and that the clients must implement.  It also
changes some shared code to use these functions.

gdb/ChangeLog:

	* target/symbol.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add target/symbol.h.
	* target.h: Include target/symbol.h.
	* minsyms.c (find_minimal_symbol_address): New function.
	* common/agent.c: Include target/symbol.h.
	[!GDBSERVER]: Don't include objfiles.h.
	(agent_look_up_symbols): Use find_minimal_symbol_address.

gdb/gdbserver/ChangeLog:

	* symbol.c: New file.
	* Makefile.in (SFILES): Add symbol.c.
	(OBS): Add symbol.o.
Introduce common-regcache.h

This introduces common-regcache.h.  This contains two functions that
allow nat/linux-btrace.c to be simplified.  A better long term
solution would be unify the regcache code, but this is sufficient for
now.

gdb/ChangeLog:

	* common/common-regcache.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add common/common-regcache.h.
	* regcache.h: Include common-regcache.h.
	(regcache_read_pc): Don't declare.
	* regcache.c (get_thread_regcache_for_ptid): New function.
	* nat/linux-btrace.c: Don't include regcache.h.
	Include common-regcache.h.
	(perf_event_read_bts): Use get_thread_regcache_for_ptid.

gdb/gdbserver/ChangeLog:

	* regcache.h: Include common-regcache.h.
	(regcache_read_pc): Don't declare.
	* regcache.c (get_thread_regcache_for_ptid): New function.
Include common-defs.h instead of defs.h/server.h in shared code

This commit makes 19 of the 22 shared .c files in common, nat and
target include common-defs.h instead of defs.h/server.h.  The
remaining three files need slight extra work and are dealt with
in separate commits.

gdb/ChangeLog:

	* common/agent.c: Include common-defs.h.
	Don't include defs.h or server.h.
	* common/buffer.c: Likewise.
	* common/common-debug.c: Likewise.
	* common/common-utils.c: Likewise.
	* common/errors.c: Likewise.
	* common/filestuff.c: Likewise.
	* common/format.c: Likewise.
	* common/gdb_vecs.c: Likewise.
	* common/print-utils.c: Likewise.
	* common/ptid.c: Likewise.
	* common/rsp-low.c: Likewise.
	* common/signals.c: Likewise.
	* common/vec.c: Likewise.
	* common/xml-utils.c: Likewise.
	* nat/linux-osdata.c: Likewise.
	* nat/linux-procfs.c: Likewise.
	* nat/linux-ptrace.c: Likewise.
	* nat/mips-linux-watch.c: Likewise.
	* target/waitstatus.c: Likewise.
Remove GDBSERVER uses from linux-btrace.c

This commit makes nat/linux-btrace.c include common-defs.h rather
than defs.h or server.h.  A couple of minor changes were required
to support this change.

gdb/ChangeLog:

	* nat/linux-btrace.c: Include common-defs.h.
	Don't include defs.h, server.h or gdbthread.h.
	* nat/linux-btrace.h (struct target_ops): New forward declaration.
Remove GDBSERVER uses from x86-dregs.c

This commit makes nat/x86-dregs.c include common-defs.h rather than
defs.h or server.h.  An extra header required including in order to
support this change.

gdb/ChangeLog:

	* nat/x86-dregs.c: Include common-defs.h and break-common.h.
	Don't include defs.h or server.h.
Remove one GDBSERVER use from linux-waitpid.c

This commit makes nat/linux-waitpid.c include common-defs.h rather
than defs.h or server.h.  Some debug code previously only built for
gdbserver is now also built for GDB, and a use of GDBSERVER has had
to remain in order to select the variable used to determine whether
debug printing should be enabled.

gdb/ChangeLog:

	* linux-nat.c (debug_linux_nat): Make nonstatic.
	* nat/linux-waitpid.c: Include common-defs.h.
	Don't include defs.h, server.h or signal.h.
	(debug_linux_waitpid): New macro and extern.
	(linux_debug): Use debug_linux_waitpid and debug_vprintf.
Introduce current_inferior_ptid

This commit introduces a new function, current_inferior_ptid, that
allows shared code to obtain the ptid of the current inferior.

gdb/ChangeLog:

	* common/common-inferior.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add common/common-inferior.h.
	* inferior.h: Include common-inferior.h.
	* inferior.c (current_inferior_ptid): New function.
	* x86-linux-nat.c (x86_linux_dr_get_addr): Use the above.
	(x86_linux_dr_get_control): Likewise.
	(x86_linux_dr_get_status): Likewise.

gdb/gdbserver/ChangeLog:

	* inferiors.h: Include common-inferior.h.
	* inferiors.c (current_inferior_ptid): New function.
	* linux-x86-low.c (x86_dr_low_get_addr): Use the above.
	(x86_dr_low_get_control): Likewise.
	(x86_dr_low_get_status): Likewise.
Add x86_debug_reg_state to gdbserver

This commit introduces a new function, x86_debug_reg_state, that
allows shared x86 code to access the local mirror of a process's
debug registers.  This function already existed in GDB and was
in use by GDB's x86_linux_prepare_to_resume.  An equivalent was
written for gdbserver and gdbserver's x86_linux_prepare_to_resume
was modified to use it.

gdb/ChangeLog:

	* x86-nat.h (x86_debug_reg_state): Move declaration to...
	* nat/x86-dregs.h (x86_debug_reg_state): New declaration.

gdb/gdbserver/ChangeLog:

	* linux-x86-low.c (x86_debug_reg_state): New function.
	(x86_linux_prepare_to_resume): Use the above.
Introduce current_inferior_pid

This commit introduces a new function, current_inferior_pid, that
shared code can use to obtain the PID of the current inferior.

gdb/ChangeLog:

	* common/common-inferior.c: New file.
	* Makefile.in (SFILES): Add common/common-inferior.c.
	(COMMON_OBS): Add common/common-inferior.o.
	(common-inferior.o): New rule.
	* common/common-inferior.h (current_inferior_pid): New function.
	* x86-linux-nat.c (x86_linux_dr_set_control): Use the above.
	(x86_linux_dr_set_addr): Likewise.

gdb/gdbserver/ChangeLog:

	* Makefile.in (SFILES): Add common-inferior.c.
	(OBS): Add common-inferior.o.
	(common-inferior.o): New rule.
Add iterate_over_lwps to gdbserver

This commit introduces a new function, iterate_over_lwps, that
shared Linux code can use to call a function for each LWP that
matches certain criteria.  This function already existed in GDB
and was in use by GDB's various low-level Linux x86 debug register
setters.  An equivalent was written for gdbserver and gdbserver's
low-level Linux x86 debug register setters were modified to use
it.

gdb/ChangeLog:

	* linux-nat.h: Include nat/linux-nat.h.
	(iterate_over_lwps): Move declaration to nat/linux-nat.h.
	* nat/linux-nat.h (struct lwp_info): New forward declaration.
	(iterate_over_lwps_ftype): New typedef.
	(iterate_over_lwps): New declaration.
	* linux-nat.h (iterate_over_lwps): Update comment.  Use
	iterate_over_lwps_ftype.  Update callback return value check.

gdb/gdbserver/ChangeLog:

	* linux-low.h: Include nat/linux-nat.h.
	* linux-low.c (iterate_over_lwps_args): New structure.
	(iterate_over_lwps_filter): New function.
	(iterate_over_lwps): Likewise.
	* linux-x86-low.c (update_debug_registers_callback):
	Updated signature to what iterate_over_lwps expects.
	Remove PID check that iterate_over_lwps now performs.
	(x86_dr_low_set_addr): Use iterate_over_lwps.
	(x86_dr_low_set_control): Likewise.
Make linux_stop_lwp be a shared function

Both GDB and gdbserver had identical linux_stop_lwp functions.
This commit moves its declaration to nat/linux-nat.h to allow
shared code to use it.

gdb/ChangeLog:

	* linux-nat.h (linux_stop_lwp): Move declaration to...
	* nat/linux-nat.h (linux_stop_lwp): New declaration.

gdb/gdbserver/ChangeLog:

	* linux-low.h (linux_stop_lwp): Remove declaration.
Introduce basic LWP accessors

This commit introduces three accessors that shared Linux code can
use to access fields of struct lwp_info.  The GDB and gdbserver
Linux x86 code is modified to use them.

gdb/ChangeLog:

	* nat/linux-nat.h (ptid_of_lwp): New declaration.
	(lwp_is_stopped): Likewise.
	(lwp_is_stopped_by_watchpoint): Likewise.
	* linux-nat.c (ptid_of_lwp): New function.
	(lwp_is_stopped): Likewise.
	(lwp_is_stopped_by_watchpoint): Likewise.
	* x86-linux-nat.c (update_debug_registers_callback):
	Use lwp_is_stopped.
	(x86_linux_prepare_to_resume): Use ptid_of_lwp and
	lwp_is_stopped_by_watchpoint.

gdb/gdbserver/ChangeLog:

	* linux-low.c (ptid_of_lwp): New function.
	(lwp_is_stopped): Likewise.
	(lwp_is_stopped_by_watchpoint): Likewise.
	* linux-x86-low.c (update_debug_registers_callback):
	Use lwp_is_stopped.
	(x86_linux_prepare_to_resume): Use ptid_of_lwp and
	lwp_is_stopped_by_watchpoint.
Change signature of linux_target_ops.new_thread

This commit changes the signature of linux_target_ops.new_thread in
gdbserver to match that used in GDB's equivalent.

gdb/gdbserver/ChangeLog:

	* linux-low.h (linux_target_ops) <new_thread>: Changed signature.
	* linux-arm-low.c (arm_new_thread): Likewise.
	* linux-aarch64-low.c (aarch64_linux_new_thread): Likewise.
	* linux-mips-low.c (mips_linux_new_thread): Likewise.
	* linux-x86-low.c (x86_linux_new_thread): Likewise.
	* linux-low.c (add_lwp): Update the_low_target.new_thread call.
Make lwp_info.arch_private handling shared

This commit moves the code to handle lwp_info.arch_private for
Linux x86 into a new shared file, nat/x86-linux.c.

gdb/ChangeLog:

	* nat/x86-linux.h: New file.
	* nat/x86-linux.c: Likewise.
	* Makefile.in (HFILES_NO_SRCDIR): Add nat/x86-linux.h.
	(x86-linux.o): New rule.
	* config/i386/linux.mh (NATDEPFILES): Add x86-linux.o.
	* config/i386/linux64.mh (NATDEPFILES): Likewise.
	* nat/linux-nat.h (struct arch_lwp_info): New forward declaration.
	(lwp_set_arch_private_info): New declaration.
	(lwp_arch_private_info): Likewise.
	* linux-nat.c (lwp_set_arch_private_info): New function.
	(lwp_arch_private_info): Likewise.
	* x86-linux-nat.c: Include nat/x86-linux.h.
	(arch_lwp_info): Removed structure.
	(update_debug_registers_callback):
	Use lwp_set_debug_registers_changed.
	(x86_linux_prepare_to_resume): Use lwp_debug_registers_changed
	and lwp_set_debug_registers_changed.
	(x86_linux_new_thread): Use lwp_set_debug_registers_changed.

gdb/gdbserver/ChangeLog:

	* Makefile.in (x86-linux.o): New rule.
	* configure.srv: Add x86-linux.o to relevant targets.
	* linux-low.c (lwp_set_arch_private_info): New function.
	(lwp_arch_private_info): Likewise.
	* linux-x86-low.c: Include nat/x86-linux.h.
	(arch_lwp_info): Removed structure.
	(update_debug_registers_callback):
	Use lwp_set_debug_registers_changed.
	(x86_linux_prepare_to_resume): Use lwp_debug_registers_changed
	and lwp_set_debug_registers_changed.
	(x86_linux_new_thread): Use lwp_set_debug_registers_changed.
Rename gdbserver's low-level Linux x86 debug register accessors

This commit renames gdbserver's low-level Linux x86 debug register
accessors to the same names used by GDB.

gdb/gdbserver/ChangeLog:

	* linux-x86-low.c (x86_dr_low_set_addr): Renamed as...
	(x86_linux_dr_set_addr): New function.
	(x86_dr_low_get_addr): Renamed as...
	(x86_linux_dr_get_addr): New function.
	(x86_dr_low_set_control): Renamed as...
	(x86_linux_dr_set_control): New function.
	(x86_dr_low_get_control): Renamed as...
	(x86_linux_dr_get_control): New function.
	(x86_dr_low_get_status): Renamed as...
	(x86_linux_dr_get_status): New function.
	(x86_dr_low): Updated with new function names.
Linux x86 low-level debug register code synchronization

This commit makes several small changes to the low-level debug
register code for Linux x86, making the code in the GDB and
gdbserver implementations identical.

gdb/ChangeLog:

	* x86-linux-nat.c (x86_linux_dr_set_addr): Updated assertion.
	(x86_linux_new_thread): Renamed argument.

gdb/gdbserver/ChangeLog:

	* linux-x86-low.c (x86_linux_dr_get): Add assertion.
	Use perror_with_name.
	(x86_linux_dr_set): Likewise.
Linux x86 low-level debug register comment synchronization

This commit updates comments in the low-level debug register code for
Linux x86, making GDB's and gdbserver's implementations identical.

gdb/ChangeLog:

	* x86-linux-nat.c (x86_linux_dr_get): Updated comments.
	(x86_linux_dr_set): Likewise.
	(x86_linux_dr_get_addr): Likewise.
	(x86_linux_dr_get_control): Likewise.
	(x86_linux_dr_get_status): Likewise.
	(update_debug_registers_callback): Likewise.
	(x86_linux_dr_set_control): Likewise.
	(x86_linux_dr_set_addr): Likewise.
	(x86_linux_prepare_to_resume): Likewise.
	(x86_linux_new_thread): Likewise.

gdb/gdbserver/ChangeLog:

	* linux-x86-low.c (x86_linux_dr_get): Updated comments.
	(x86_linux_dr_set): Likewise.
	(update_debug_registers_callback): Likewise.
	(x86_linux_dr_set_addr): Likewise.
	(x86_linux_dr_get_addr): Likewise.
	(x86_linux_dr_set_control): Likewise.
	(x86_linux_dr_get_control): Likewise.
	(x86_linux_dr_get_status): Likewise.
	(x86_linux_prepare_to_resume): Likewise.