utility.c revision 136dcc5ce628a1ba600a6818e5cb24d5f15eb016 
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 <signal.h>
21#include <assert.h>
22#include <string.h>
23#include <errno.h>
24
25#include "utility.h"
26
27/* Get a word from pid using ptrace. The result is the return value. */
28int get_remote_word(int pid, void *src)
29{
30    return ptrace(PTRACE_PEEKTEXT, pid, src, NULL);
31}
32
33
34/* Handy routine to read aggregated data from pid using ptrace. The read
35 * values are written to the dest locations directly.
36 */
37void get_remote_struct(int pid, void *src, void *dst, size_t size)
38{
39    unsigned int i;
40
41    for (i = 0; i+4 <= size; i+=4) {
42        *(int *)((char *)dst+i) = ptrace(PTRACE_PEEKTEXT, pid, (char *)src+i, NULL);
43    }
44
45    if (i < size) {
46        int val;
47
48        assert((size - i) < 4);
49        val = ptrace(PTRACE_PEEKTEXT, pid, (char *)src+i, NULL);
50        while (i < size) {
51            ((unsigned char *)dst)[i] = val & 0xff;
52            i++;
53            val >>= 8;
54        }
55    }
56}
57
58/* Map a pc address to the name of the containing ELF file */
59const char *map_to_name(mapinfo *mi, unsigned pc, const char* def)
60{
61    while(mi) {
62        if((pc >= mi->start) && (pc < mi->end)){
63            return mi->name;
64        }
65        mi = mi->next;
66    }
67    return def;
68}
69
70/* Find the containing map info for the pc */
71const mapinfo *pc_to_mapinfo(mapinfo *mi, unsigned pc, unsigned *rel_pc)
72{
73    *rel_pc = pc;
74    while(mi) {
75        if((pc >= mi->start) && (pc < mi->end)){
76            // Only calculate the relative offset for shared libraries
77            if (strstr(mi->name, ".so")) {
78                *rel_pc -= mi->start;
79            }
80            return mi;
81        }
82        mi = mi->next;
83    }
84    return NULL;
85}
86
87/*
88 * Returns true if the specified signal has an associated address (i.e. it
89 * sets siginfo_t.si_addr).
90 */
91bool signal_has_address(int sig)
92{
93    switch (sig) {
94        case SIGILL:
95        case SIGFPE:
96        case SIGSEGV:
97        case SIGBUS:
98            return true;
99        default:
100            return false;
101    }
102}
103