1 /* system/debuggerd/utility.c
2 **
3 ** Copyright 2008, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17
18 #include <sys/ptrace.h>
19 #include <sys/exec_elf.h>
20 #include <assert.h>
21 #include <string.h>
22 #include <errno.h>
23
24 #include "utility.h"
25
26 /* Get a word from pid using ptrace. The result is the return value. */
get_remote_word(int pid,void * src)27 int get_remote_word(int pid, void *src)
28 {
29 return ptrace(PTRACE_PEEKTEXT, pid, src, NULL);
30 }
31
32
33 /* Handy routine to read aggregated data from pid using ptrace. The read
34 * values are written to the dest locations directly.
35 */
get_remote_struct(int pid,void * src,void * dst,size_t size)36 void get_remote_struct(int pid, void *src, void *dst, size_t size)
37 {
38 unsigned int i;
39
40 for (i = 0; i+4 <= size; i+=4) {
41 *(int *)(dst+i) = ptrace(PTRACE_PEEKTEXT, pid, src+i, NULL);
42 }
43
44 if (i < size) {
45 int val;
46
47 assert((size - i) < 4);
48 val = ptrace(PTRACE_PEEKTEXT, pid, src+i, NULL);
49 while (i < size) {
50 ((unsigned char *)dst)[i] = val & 0xff;
51 i++;
52 val >>= 8;
53 }
54 }
55 }
56
57 /* Map a pc address to the name of the containing ELF file */
map_to_name(mapinfo * mi,unsigned pc,const char * def)58 const char *map_to_name(mapinfo *mi, unsigned pc, const char* def)
59 {
60 while(mi) {
61 if((pc >= mi->start) && (pc < mi->end)){
62 return mi->name;
63 }
64 mi = mi->next;
65 }
66 return def;
67 }
68
69 /* Find the containing map info for the pc */
pc_to_mapinfo(mapinfo * mi,unsigned pc,unsigned * rel_pc)70 const mapinfo *pc_to_mapinfo(mapinfo *mi, unsigned pc, unsigned *rel_pc)
71 {
72 while(mi) {
73 if((pc >= mi->start) && (pc < mi->end)){
74 // Only calculate the relative offset for shared libraries
75 if (strstr(mi->name, ".so")) {
76 *rel_pc = pc - mi->start;
77 }
78 return mi;
79 }
80 mi = mi->next;
81 }
82 return NULL;
83 }
84