Commit | Line | Data |
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c906108c | 1 | /* Simulate breakpoints by patching locations in the target system, for GDB. |
f4f9705a | 2 | |
28e7fd62 | 3 | Copyright (C) 1990-2013 Free Software Foundation, Inc. |
f4f9705a | 4 | |
c906108c SS |
5 | Contributed by Cygnus Support. Written by John Gilmore. |
6 | ||
c5aa993b | 7 | This file is part of GDB. |
c906108c | 8 | |
c5aa993b JM |
9 | This program is free software; you can redistribute it and/or modify |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 12 | (at your option) any later version. |
c906108c | 13 | |
c5aa993b JM |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
c906108c | 18 | |
c5aa993b | 19 | You should have received a copy of the GNU General Public License |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
21 | |
22 | #include "defs.h" | |
23 | ||
aaab4dba AC |
24 | /* This file is only useful if BREAKPOINT_FROM_PC is set. If not, we |
25 | punt. */ | |
c906108c SS |
26 | |
27 | #include "symtab.h" | |
28 | #include "breakpoint.h" | |
29 | #include "inferior.h" | |
30 | #include "target.h" | |
35c63cd8 | 31 | #include "gdb_string.h" |
c906108c SS |
32 | |
33 | ||
8181d85f DJ |
34 | /* Insert a breakpoint on targets that don't have any better |
35 | breakpoint support. We read the contents of the target location | |
36 | and stash it, then overwrite it with a breakpoint instruction. | |
37 | BP_TGT->placed_address is the target location in the target | |
38 | machine. BP_TGT->shadow_contents is some memory allocated for | |
39 | saving the target contents. It is guaranteed by the caller to be | |
40 | long enough to save BREAKPOINT_LEN bytes (this is accomplished via | |
41 | BREAKPOINT_MAX). */ | |
c906108c SS |
42 | |
43 | int | |
ae4b2284 MD |
44 | default_memory_insert_breakpoint (struct gdbarch *gdbarch, |
45 | struct bp_target_info *bp_tgt) | |
c906108c SS |
46 | { |
47 | int val; | |
f4f9705a | 48 | const unsigned char *bp; |
35c63cd8 | 49 | gdb_byte *readbuf; |
c906108c SS |
50 | |
51 | /* Determine appropriate breakpoint contents and size for this address. */ | |
3b3b875c | 52 | bp = gdbarch_breakpoint_from_pc |
ae4b2284 | 53 | (gdbarch, &bp_tgt->placed_address, &bp_tgt->placed_size); |
c906108c | 54 | if (bp == NULL) |
8a3fe4f8 | 55 | error (_("Software breakpoints not implemented for this target.")); |
c906108c | 56 | |
35c63cd8 JB |
57 | /* Save the memory contents in the shadow_contents buffer and then |
58 | write the breakpoint instruction. */ | |
8181d85f | 59 | bp_tgt->shadow_len = bp_tgt->placed_size; |
35c63cd8 JB |
60 | readbuf = alloca (bp_tgt->placed_size); |
61 | val = target_read_memory (bp_tgt->placed_address, readbuf, | |
8181d85f | 62 | bp_tgt->placed_size); |
c906108c | 63 | if (val == 0) |
35c63cd8 JB |
64 | { |
65 | memcpy (bp_tgt->shadow_contents, readbuf, bp_tgt->placed_size); | |
66 | val = target_write_raw_memory (bp_tgt->placed_address, bp, | |
67 | bp_tgt->placed_size); | |
68 | } | |
c906108c SS |
69 | |
70 | return val; | |
71 | } | |
72 | ||
73 | ||
74 | int | |
ae4b2284 MD |
75 | default_memory_remove_breakpoint (struct gdbarch *gdbarch, |
76 | struct bp_target_info *bp_tgt) | |
c906108c | 77 | { |
f0ba3972 PA |
78 | return target_write_raw_memory (bp_tgt->placed_address, bp_tgt->shadow_contents, |
79 | bp_tgt->placed_size); | |
c906108c | 80 | } |
917317f4 JM |
81 | |
82 | ||
917317f4 | 83 | int |
a6d9a66e UW |
84 | memory_insert_breakpoint (struct gdbarch *gdbarch, |
85 | struct bp_target_info *bp_tgt) | |
917317f4 | 86 | { |
a6d9a66e | 87 | return gdbarch_memory_insert_breakpoint (gdbarch, bp_tgt); |
917317f4 JM |
88 | } |
89 | ||
917317f4 | 90 | int |
a6d9a66e UW |
91 | memory_remove_breakpoint (struct gdbarch *gdbarch, |
92 | struct bp_target_info *bp_tgt) | |
917317f4 | 93 | { |
a6d9a66e | 94 | return gdbarch_memory_remove_breakpoint (gdbarch, bp_tgt); |
917317f4 | 95 | } |