fs_config_generate.c revision 06b91b9bcf4410d7b8c8c5e10a717671dd327c35 
1/*
2 * Copyright (C) 2015 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 <stdbool.h>
18#include <stdio.h>
19#include <stdlib.h>
20#include <unistd.h>
21
22#include <private/android_filesystem_config.h>
23
24/*
25 * This program expects android_device_dirs and android_device_files
26 * to be defined in the supplied android_filesystem_config.h file in
27 * the device/<vendor>/<product> $(TARGET_DEVICE_DIR). Then generates
28 * the binary format used in the /system/etc/fs_config_dirs and
29 * the /system/etc/fs_config_files to be used by the runtimes.
30 */
31#include "android_filesystem_config.h"
32
33#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_DIRS
34  static const struct fs_path_config android_device_dirs[] = {
35};
36#endif
37
38#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_FILES
39static const struct fs_path_config android_device_files[] = {
40#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_DIRS
41    { 0, AID_ROOT, AID_ROOT, 0, "system/etc/fs_config_dirs" },
42#endif
43    { 0, AID_ROOT, AID_ROOT, 0, "system/etc/fs_config_files" },
44};
45#endif
46
47static void usage() {
48  fprintf(stderr,
49    "Generate binary content for fs_config_dirs (-D) and fs_config_files (-F)\n"
50    "from device-specific android_filesystem_config.h override\n\n"
51    "Usage: fs_config_generate -D|-F [-o output-file]\n");
52}
53
54int main(int argc, char** argv) {
55  const struct fs_path_config *pc;
56  const struct fs_path_config *end;
57  bool dir = false, file = false;
58  FILE *fp = stdout;
59  int opt;
60
61  while((opt = getopt(argc, argv, "DFho:")) != -1) {
62    switch(opt) {
63    case 'D':
64      if (file) {
65        fprintf(stderr, "Must specify only -D or -F\n");
66        usage();
67        exit(EXIT_FAILURE);
68      }
69      dir = true;
70      break;
71    case 'F':
72      if (dir) {
73        fprintf(stderr, "Must specify only -F or -D\n");
74        usage();
75        exit(EXIT_FAILURE);
76      }
77      file = true;
78      break;
79    case 'o':
80      if (fp != stdout) {
81        fprintf(stderr, "Specify only one output file\n");
82        usage();
83        exit(EXIT_FAILURE);
84      }
85      fp = fopen(optarg, "w");
86      if (fp == NULL) {
87        fprintf(stderr, "Can not open \"%s\"\n", optarg);
88        exit(EXIT_FAILURE);
89      }
90      break;
91    case 'h':
92      usage();
93      exit(EXIT_SUCCESS);
94    default:
95      usage();
96      exit(EXIT_FAILURE);
97    }
98  }
99
100  if (!file && !dir) {
101    fprintf(stderr, "Must specify either -F or -D\n");
102    usage();
103    exit(EXIT_FAILURE);
104  }
105
106  if (dir) {
107    pc = android_device_dirs;
108    end = &android_device_dirs[sizeof(android_device_dirs) / sizeof(android_device_dirs[0])];
109  } else {
110    pc = android_device_files;
111    end = &android_device_files[sizeof(android_device_files) / sizeof(android_device_files[0])];
112  }
113  for(; (pc < end) && pc->prefix; pc++) {
114    char buffer[512];
115    ssize_t len = fs_config_generate(buffer, sizeof(buffer), pc);
116    if (len < 0) {
117      fprintf(stderr, "Entry too large\n");
118      exit(EXIT_FAILURE);
119    }
120    if (fwrite(buffer, 1, len, fp) != (size_t)len) {
121      fprintf(stderr, "Write failure\n");
122      exit(EXIT_FAILURE);
123    }
124  }
125  fclose(fp);
126
127  return 0;
128}
129