X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fmem-break.c;h=e35d0a50716491a288eb7183e64636153330b45a;hb=1a457753cfad05989574c671a221ffce2d5df703;hp=74fd8dba8e1f00d7544019c6161d1e361c027943;hpb=be7d37a2c35f12d7fdcc9ad65333c0a81460cd89;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/mem-break.c b/gdb/mem-break.c index 74fd8dba8e..e35d0a5071 100644 --- a/gdb/mem-break.c +++ b/gdb/mem-break.c @@ -1,6 +1,6 @@ /* Simulate breakpoints by patching locations in the target system, for GDB. - Copyright (C) 1990-2013 Free Software Foundation, Inc. + Copyright (C) 1990-2017 Free Software Foundation, Inc. Contributed by Cygnus Support. Written by John Gilmore. @@ -24,9 +24,6 @@ #include "breakpoint.h" #include "inferior.h" #include "target.h" -#include "gdb_string.h" - - /* Insert a breakpoint on targets 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. @@ -40,27 +37,33 @@ int 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 = gdbarch_breakpoint_from_pc - (gdbarch, &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 in the shadow_contents buffer and then write the breakpoint instruction. */ - bp_tgt->shadow_len = bp_tgt->placed_size; - readbuf = alloca (bp_tgt->placed_size); - val = target_read_memory (bp_tgt->placed_address, readbuf, - bp_tgt->placed_size); + readbuf = (gdb_byte *) alloca (bplen); + val = target_read_memory (addr, readbuf, bplen); if (val == 0) { - memcpy (bp_tgt->shadow_contents, readbuf, bp_tgt->placed_size); - val = target_write_raw_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; @@ -71,21 +74,58 @@ int default_memory_remove_breakpoint (struct gdbarch *gdbarch, struct bp_target_info *bp_tgt) { + 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, - bp_tgt->placed_size); + bplen); } int -memory_insert_breakpoint (struct gdbarch *gdbarch, +memory_insert_breakpoint (struct target_ops *ops, struct gdbarch *gdbarch, struct bp_target_info *bp_tgt) { return gdbarch_memory_insert_breakpoint (gdbarch, bp_tgt); } int -memory_remove_breakpoint (struct gdbarch *gdbarch, - 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 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]; + struct cleanup *cleanup; + int ret; + + /* 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. */ + cleanup = make_show_memory_breakpoints_cleanup (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. */ + ret = (val == 0 && memcmp (bp, cur_contents, bplen) == 0); + + do_cleanups (cleanup); + return ret; +}