check_prereq.c revision 66339ad5cebeae8f4cbf7e335c67368abbb91223 
1/*
2 * Copyright (C) 2009 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/system_properties.h>
20#include <cutils/properties.h>
21
22// Compare the timestamp of the new build (passed on the command line)
23// against the current value of ro.build.date.utc.  Exit successfully
24// if the new build is newer than the current build (or if the
25// timestamps are the same).
26int main(int argc, char** argv) {
27  if (argc != 2) {
28 usage:
29    fprintf(stderr, "usage: %s <timestamp>\n", argv[0]);
30    return 2;
31  }
32
33  char value[PROPERTY_VALUE_MAX];
34  char* default_value = "0";
35
36  property_get("ro.build.date.utc", value, default_value);
37
38  long current = strtol(value, NULL, 10);
39  char* end;
40  long install = strtol(argv[1], &end, 10);
41
42  printf("current build time: [%ld]  new build time: [%ld]\n",
43         current, install);
44
45  return (*end == 0 && current > 0 && install >= current) ? 0 : 1;
46}
47