old-cross-binutils/gdb/gdbserver/server.h
Yao Qi 6085d6f695 Disable Z0 packet on aarch64 on multi-arch debugging
In multi-arch debugging, if GDB sends Z0 packet, GDBserver should be
able to do several things below:

 - choose the right breakpoint instruction to insert according to the
   information available, such as 'kind' in Z0 packet and address,

 - choose the right breakpoint instruction to check memory writes and
   validate inserted memory breakpoint

 - be aware of different breakpoint instructions in $ARCH_breakpoint_at.

unfortunately GDBserver can't do them now.  Although x86 GDBserver
supports multi-arch, it doesn't need to support them above because
breakpoint instruction on i686 and x86_64 is the same.  However,
breakpoint instructions on aarch64 and arm (arm mode, thumb1, and thumb2)
are different.

I tried to teach aarch64 GDBserver backend to be really
multi-arch-capable in the following ways,

 - linux_low_target return the right breakpoint instruction according to
   the 'kind' in Z0 packet, and insert_memory_breakpoint can do the right
   thing.
 - once breakpoint is inserted, the breakpoint data and length is recorded
   in each breakpoint object, so that validate_breakpoint and
   check_mem_write can get the right breakpoint instruction from each
   breakpoint object, rather than from global variable breakpoint_data.
 - linux_low_target needs another hook function for pc increment after
   hitting a breakpoint.
 - let set_breakpoint_at, which is widely used for tracepoint, use the
   'default' breakpoint instruction.  We can always use aarch64 breakpoint
   instruction since arm doesn't support tracepoint yet.

looks it is not a small piece of work, so I decide to disable Z0 packet
on multi-arch, which means aarch64 GDBserver only supports Z0 packet
if it is started to debug only one process (extended protocol is not
used) and process target description is 64-bit.

gdb/gdbserver:

2015-08-04  Yao Qi  <yao.qi@linaro.org>

	* linux-aarch64-low.c (aarch64_supports_z_point_type): Return
	0 for Z_PACKET_SW_BP if it may be used in multi-arch debugging.
	* server.c (extended_protocol): Remove "static".
	* server.h (extended_protocol): Declare it.
2015-08-04 14:34:14 +01:00

132 lines
3.5 KiB
C

/* Common definitions for remote server for GDB.
Copyright (C) 1993-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef SERVER_H
#define SERVER_H
#include "common-defs.h"
gdb_static_assert (sizeof (CORE_ADDR) >= sizeof (void *));
#ifdef __MINGW32CE__
#include "wincecompat.h"
#endif
#include "version.h"
#if !HAVE_DECL_STRERROR
#ifndef strerror
extern char *strerror (int); /* X3.159-1989 4.11.6.2 */
#endif
#endif
#if !HAVE_DECL_PERROR
#ifndef perror
extern void perror (const char *);
#endif
#endif
#if !HAVE_DECL_VASPRINTF
extern int vasprintf(char **strp, const char *fmt, va_list ap);
#endif
#if !HAVE_DECL_VSNPRINTF
int vsnprintf(char *str, size_t size, const char *format, va_list ap);
#endif
#ifdef IN_PROCESS_AGENT
# define PROG "ipa"
#else
# define PROG "gdbserver"
#endif
#include "buffer.h"
#include "xml-utils.h"
#include "regcache.h"
#include "gdb_signals.h"
#include "target.h"
#include "mem-break.h"
#include "gdbthread.h"
#include "inferiors.h"
/* Target-specific functions */
void initialize_low ();
/* Public variables in server.c */
extern ptid_t cont_thread;
extern ptid_t general_thread;
extern int server_waiting;
extern int pass_signals[];
extern int program_signals[];
extern int program_signals_p;
extern int disable_packet_vCont;
extern int disable_packet_Tthread;
extern int disable_packet_qC;
extern int disable_packet_qfThreadInfo;
extern int run_once;
extern int multi_process;
extern int report_fork_events;
extern int report_vfork_events;
extern int non_stop;
extern int extended_protocol;
/* True if the "swbreak+" feature is active. In that case, GDB wants
us to report whether a trap is explained by a software breakpoint
and for the server to handle PC adjustment if necessary on this
target. Only enabled if the target supports it. */
extern int swbreak_feature;
/* True if the "hwbreak+" feature is active. In that case, GDB wants
us to report whether a trap is explained by a hardware breakpoint.
Only enabled if the target supports it. */
extern int hwbreak_feature;
extern int disable_randomization;
#if USE_WIN32API
#include <winsock2.h>
typedef SOCKET gdb_fildes_t;
#else
typedef int gdb_fildes_t;
#endif
#include "event-loop.h"
/* Functions from server.c. */
extern int handle_serial_event (int err, gdb_client_data client_data);
extern int handle_target_event (int err, gdb_client_data client_data);
#include "remote-utils.h"
#include "utils.h"
#include "debug.h"
/* Maximum number of bytes to read/write at once. The value here
is chosen to fill up a packet (the headers account for the 32). */
#define MAXBUFBYTES(N) (((N)-32)/2)
/* Buffer sizes for transferring memory, registers, etc. Set to a constant
value to accomodate multiple register formats. This value must be at least
as large as the largest register set supported by gdbserver. */
#define PBUFSIZ 16384
#endif /* SERVER_H */