/* Simulate breakpoints by patching locations in the target system, for GDB.
- Copyright (C) 1990, 1991, 1992, 1993, 1995, 1997, 1998, 1999, 2000,
- 2002 Free Software Foundation, Inc.
+ Copyright (C) 1990-2020 Free Software Foundation, Inc.
Contributed by Cygnus Support. Written by John Gilmore.
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 2 of the License, or
+ 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,
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, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
-
-/* This file is only useful if BREAKPOINT_FROM_PC is set. If not, we
- punt. */
-
#include "symtab.h"
#include "breakpoint.h"
#include "inferior.h"
#include "target.h"
-
+#include "gdbarch.h"
/* Insert a breakpoint on targets that don't have any better
breakpoint support. We read the contents of the target location
BREAKPOINT_MAX). */
int
-default_memory_insert_breakpoint (struct bp_target_info *bp_tgt)
+default_memory_insert_breakpoint (struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt)
{
- int val;
+ CORE_ADDR addr = bp_tgt->placed_address;
const unsigned char *bp;
+ gdb_byte *readbuf;
int bplen;
+ int val;
/* Determine appropriate breakpoint contents and size for this address. */
- bp = BREAKPOINT_FROM_PC (&bp_tgt->placed_address, &bp_tgt->placed_size);
- if (bp == NULL)
- error (_("Software breakpoints not implemented for this target."));
+ bp = gdbarch_sw_breakpoint_from_kind (gdbarch, bp_tgt->kind, &bplen);
- /* Save the memory contents. */
- bp_tgt->shadow_len = bp_tgt->placed_size;
- val = target_read_memory (bp_tgt->placed_address, bp_tgt->shadow_contents,
- bp_tgt->placed_size);
-
- /* Write the breakpoint. */
+ /* Save the memory contents in the shadow_contents buffer and then
+ write the breakpoint instruction. */
+ readbuf = (gdb_byte *) alloca (bplen);
+ val = target_read_memory (addr, readbuf, bplen);
if (val == 0)
- val = target_write_memory (bp_tgt->placed_address, bp,
- bp_tgt->placed_size);
+ {
+ /* These must be set together, either before or after the shadow
+ read, so that if we're "reinserting" a breakpoint that
+ doesn't have a shadow yet, the breakpoint masking code inside
+ target_read_memory doesn't mask out this breakpoint using an
+ unfilled shadow buffer. The core may be trying to reinsert a
+ permanent breakpoint, for targets that support breakpoint
+ conditions/commands on the target side for some types of
+ breakpoints, such as target remote. */
+ bp_tgt->shadow_len = bplen;
+ memcpy (bp_tgt->shadow_contents, readbuf, bplen);
+
+ val = target_write_raw_memory (addr, bp, bplen);
+ }
return val;
}
int
-default_memory_remove_breakpoint (struct bp_target_info *bp_tgt)
+default_memory_remove_breakpoint (struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt)
{
- return target_write_memory (bp_tgt->placed_address, bp_tgt->shadow_contents,
- bp_tgt->placed_size);
+ int bplen;
+
+ gdbarch_sw_breakpoint_from_kind (gdbarch, bp_tgt->kind, &bplen);
+
+ return target_write_raw_memory (bp_tgt->placed_address, bp_tgt->shadow_contents,
+ bplen);
}
int
-memory_insert_breakpoint (struct bp_target_info *bp_tgt)
+memory_insert_breakpoint (struct target_ops *ops, struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt)
{
- return MEMORY_INSERT_BREAKPOINT (bp_tgt);
+ return gdbarch_memory_insert_breakpoint (gdbarch, bp_tgt);
}
int
-memory_remove_breakpoint (struct bp_target_info *bp_tgt)
+memory_remove_breakpoint (struct target_ops *ops, struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt,
+ enum remove_bp_reason reason)
{
- return MEMORY_REMOVE_BREAKPOINT (bp_tgt);
+ return gdbarch_memory_remove_breakpoint (gdbarch, bp_tgt);
+}
+
+int
+memory_validate_breakpoint (struct gdbarch *gdbarch,
+ struct bp_target_info *bp_tgt)
+{
+ CORE_ADDR addr = bp_tgt->placed_address;
+ const gdb_byte *bp;
+ int val;
+ int bplen;
+ gdb_byte cur_contents[BREAKPOINT_MAX];
+
+ /* Determine appropriate breakpoint contents and size for this
+ address. */
+ bp = gdbarch_breakpoint_from_pc (gdbarch, &addr, &bplen);
+
+ if (bp == NULL)
+ return 0;
+
+ /* Make sure we see the memory breakpoints. */
+ scoped_restore restore_memory
+ = make_scoped_restore_show_memory_breakpoints (1);
+ val = target_read_memory (addr, cur_contents, bplen);
+
+ /* If our breakpoint is no longer at the address, this means that
+ the program modified the code on us, so it is wrong to put back
+ the old value. */
+ return (val == 0 && memcmp (bp, cur_contents, bplen) == 0);
}
projects / deliverable / binutils-gdb.git / blobdiff