logwrapper.c revision 75c289aab9b81dc2235680cf141a4b183ee49391 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <sys/wait.h>
20
21#include <logwrap/logwrap.h>
22
23#include "cutils/log.h"
24
25void fatal(const char *msg) {
26    fprintf(stderr, "%s", msg);
27    ALOG(LOG_ERROR, "logwrapper", "%s", msg);
28    exit(-1);
29}
30
31void usage() {
32    fatal(
33        "Usage: logwrapper [-d] BINARY [ARGS ...]\n"
34        "\n"
35        "Forks and executes BINARY ARGS, redirecting stdout and stderr to\n"
36        "the Android logging system. Tag is set to BINARY, priority is\n"
37        "always LOG_INFO.\n"
38        "\n"
39        "-d: Causes logwrapper to SIGSEGV when BINARY terminates\n"
40        "    fault address is set to the status of wait()\n");
41}
42
43int main(int argc, char* argv[]) {
44    int seg_fault_on_exit = 0;
45    int status = 0xAAAA;
46    int rc;
47
48    if (argc < 2) {
49        usage();
50    }
51
52    if (strncmp(argv[1], "-d", 2) == 0) {
53        seg_fault_on_exit = 1;
54        argc--;
55        argv++;
56    }
57
58    if (argc < 2) {
59        usage();
60    }
61
62    rc = logwrap(argc - 1, &argv[1], &status, true);
63    if (!rc) {
64        if (WIFEXITED(status))
65            rc = WEXITSTATUS(status);
66        else
67            rc = -ECHILD;
68    }
69
70    if (seg_fault_on_exit) {
71        *(int *)status = 0;  // causes SIGSEGV with fault_address = status
72    }
73
74    return rc;
75}
76