/* Simulate breakpoints by patching locations in the target system, for GDB. Copyright 1990, 1991 Free Software Foundation, Inc. Contributed by Cygnus Support. Written by John Gilmore. 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 2 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, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "defs.h" #ifdef BREAKPOINT /* This file is only useful if BREAKPOINT is set. If not, we punt. */ #include <stdio.h> #include "breakpoint.h" #include "inferior.h" #include "target.h" /* This is the sequence of bytes we insert for a breakpoint. On some machines, breakpoints are handled by the target environment and we don't have to worry about them here. */ static char break_insn[] = BREAKPOINT; /* This is only to check that BREAKPOINT fits in BREAKPOINT_MAX bytes. */ static char check_break_insn_size[BREAKPOINT_MAX] = BREAKPOINT; /* Insert a breakpoint on machines that don't have any better breakpoint support. We read the contents of the target location and stash it, then overwrite it with a breakpoint instruction. ADDR is the target location in the target machine. CONTENTS_CACHE is a pointer to memory allocated for saving the target contents. It is guaranteed by the caller to be long enough to save sizeof BREAKPOINT bytes. FIXME: This size is target_arch dependent and should be available in the target_arch transfer vector, if we ever have one... */ int memory_insert_breakpoint (addr, contents_cache) CORE_ADDR addr; char *contents_cache; { int val; val = target_read_memory (addr, contents_cache, sizeof break_insn); if (val == 0) val = target_write_memory (addr, break_insn, sizeof break_insn); return val; } int memory_remove_breakpoint (addr, contents_cache) CORE_ADDR addr; char *contents_cache; { return target_write_memory (addr, contents_cache, sizeof break_insn); } int memory_breakpoint_size = sizeof (break_insn); #else /* BREAKPOINT */ char nogo[] = "Breakpoints not implemented for this target."; int memory_insert_breakpoint (addr, contents_cache) CORE_ADDR addr; char *contents_cache; { error (nogo); return 0; /* lint */ } int memory_remove_breakpoint (addr, contents_cache) CORE_ADDR addr; char *contents_cache; { error (nogo); return 0; /* lint */ } int memory_breakpoint_size = -1; #endif /* BREAKPOINT */