utility.c revision 849249064cae9c1bb23b0204b5d35b832567801e
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. */
27int 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 */
36void 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 *)((char *)dst+i) = ptrace(PTRACE_PEEKTEXT, pid, (char *)src+i, NULL);
42    }
43
44    if (i < size) {
45        int val;
46
47        assert((size - i) < 4);
48        val = ptrace(PTRACE_PEEKTEXT, pid, (char *)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 */
58const 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 */
70const 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