platform_system_core/logwrapper/logwrapper.c

99 lines
2.8 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
#include <logwrap/logwrap.h>
#include <cutils/klog.h>
#include "cutils/log.h"
void fatal(const char *msg) {
fprintf(stderr, "%s", msg);
ALOG(LOG_ERROR, "logwrapper", "%s", msg);
exit(-1);
}
void usage() {
fatal(
"Usage: logwrapper [-a] [-d] [-k] BINARY [ARGS ...]\n"
"\n"
"Forks and executes BINARY ARGS, redirecting stdout and stderr to\n"
"the Android logging system. Tag is set to BINARY, priority is\n"
"always LOG_INFO.\n"
"\n"
"-a: Causes logwrapper to do abbreviated logging.\n"
" This logs up to the first 4K and last 4K of the command\n"
" being run, and logs the output when the command exits\n"
"-d: Causes logwrapper to SIGSEGV when BINARY terminates\n"
" fault address is set to the status of wait()\n"
"-k: Causes logwrapper to log to the kernel log instead of\n"
" the Android system log\n");
}
int main(int argc, char* argv[]) {
int seg_fault_on_exit = 0;
int log_target = LOG_ALOG;
bool abbreviated = false;
int ch;
int status = 0xAAAA;
int rc;
while ((ch = getopt(argc, argv, "adk")) != -1) {
switch (ch) {
case 'a':
abbreviated = true;
break;
case 'd':
seg_fault_on_exit = 1;
break;
case 'k':
log_target = LOG_KLOG;
klog_set_level(6);
break;
case '?':
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc < 1) {
usage();
}
rc = android_fork_execvp_ext(argc, &argv[0], &status, true,
log_target, abbreviated, NULL);
if (!rc) {
if (WIFEXITED(status))
rc = WEXITSTATUS(status);
else
rc = -ECHILD;
}
if (seg_fault_on_exit) {
uintptr_t fault_address = (uintptr_t) status;
*(int *) fault_address = 0; // causes SIGSEGV with fault_address = status
}
return rc;
}