fs_config_generate.c revision 256d339413a54adeceb505f9d2f062856bcbba43 
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 <ctype.h>
18#include <stdbool.h>
19#include <stdio.h>
20#include <stdlib.h>
21#include <string.h>
22#include <unistd.h>
23
24#include <private/android_filesystem_config.h>
25
26/*
27 * This program expects android_device_dirs and android_device_files
28 * to be defined in the supplied android_filesystem_config.h file in
29 * the device/<vendor>/<product> $(TARGET_DEVICE_DIR). Then generates
30 * the binary format used in the /system/etc/fs_config_dirs and
31 * the /system/etc/fs_config_files to be used by the runtimes.
32 */
33#ifdef ANDROID_FILESYSTEM_CONFIG
34#include ANDROID_FILESYSTEM_CONFIG
35#else
36#include "android_filesystem_config.h"
37#endif
38
39#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_DIRS
40static const struct fs_path_config android_device_dirs[] = { };
41#endif
42
43#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_FILES
44static const struct fs_path_config android_device_files[] = {
45#ifdef NO_ANDROID_FILESYSTEM_CONFIG_DEVICE_DIRS
46    {0000, AID_ROOT, AID_ROOT, 0, "system/etc/fs_config_dirs"},
47    {0000, AID_ROOT, AID_ROOT, 0, "vendor/etc/fs_config_dirs"},
48    {0000, AID_ROOT, AID_ROOT, 0, "oem/etc/fs_config_dirs"},
49    {0000, AID_ROOT, AID_ROOT, 0, "odm/etc/fs_config_dirs"},
50#endif
51    {0000, AID_ROOT, AID_ROOT, 0, "system/etc/fs_config_files"},
52    {0000, AID_ROOT, AID_ROOT, 0, "vendor/etc/fs_config_files"},
53    {0000, AID_ROOT, AID_ROOT, 0, "oem/etc/fs_config_files"},
54    {0000, AID_ROOT, AID_ROOT, 0, "odm/etc/fs_config_files"},
55};
56#endif
57
58static void usage() {
59  fprintf(stderr,
60    "Generate binary content for fs_config_dirs (-D) and fs_config_files (-F)\n"
61    "from device-specific android_filesystem_config.h override.  Filter based\n"
62    "on a comma separated partition list (-P) whitelist or prefixed by a\n"
63    "minus blacklist.  Partitions are identified as path references to\n"
64    "<partition>/ or system/<partition>/\n\n"
65    "Usage: fs_config_generate -D|-F [-P list] [-o output-file]\n");
66}
67
68/* If tool switches to C++, use android-base/macros.h array_size() */
69#ifndef ARRAY_SIZE /* popular macro */
70#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
71#endif
72
73int main(int argc, char** argv) {
74  const struct fs_path_config* pc;
75  const struct fs_path_config* end;
76  bool dir = false, file = false;
77  const char* partitions = NULL;
78  FILE* fp = stdout;
79  int opt;
80  static const char optstring[] = "DFP:ho:";
81
82  while ((opt = getopt(argc, argv, optstring)) != -1) {
83    switch (opt) {
84    case 'D':
85      if (file) {
86        fprintf(stderr, "Must specify only -D or -F\n");
87        usage();
88        exit(EXIT_FAILURE);
89      }
90      dir = true;
91      break;
92    case 'F':
93      if (dir) {
94        fprintf(stderr, "Must specify only -F or -D\n");
95        usage();
96        exit(EXIT_FAILURE);
97      }
98      file = true;
99      break;
100    case 'P':
101      if (partitions) {
102        fprintf(stderr, "Specify only one partition list\n");
103        usage();
104        exit(EXIT_FAILURE);
105      }
106      while (*optarg && isspace(*optarg)) ++optarg;
107      if (!optarg[0]) {
108        fprintf(stderr, "Partition list empty\n");
109        usage();
110        exit(EXIT_FAILURE);
111      }
112      if (!optarg[1]) {
113        fprintf(stderr, "Partition list too short \"%s\"\n", optarg);
114        usage();
115        exit(EXIT_FAILURE);
116      }
117      if ((optarg[0] == '-') && strchr(optstring, optarg[1]) && !optarg[2]) {
118        fprintf(stderr, "Partition list is a flag \"%s\"\n", optarg);
119        usage();
120        exit(EXIT_FAILURE);
121      }
122      partitions = optarg;
123      break;
124    case 'o':
125      if (fp != stdout) {
126        fprintf(stderr, "Specify only one output file\n");
127        usage();
128        exit(EXIT_FAILURE);
129      }
130      fp = fopen(optarg, "wb");
131      if (fp == NULL) {
132        fprintf(stderr, "Can not open \"%s\"\n", optarg);
133        exit(EXIT_FAILURE);
134      }
135      break;
136    case 'h':
137      usage();
138      exit(EXIT_SUCCESS);
139    default:
140      usage();
141      exit(EXIT_FAILURE);
142    }
143  }
144
145  if (optind < argc) {
146    fprintf(stderr, "Unknown non-argument \"%s\"\n", argv[optind]);
147    usage();
148    exit(EXIT_FAILURE);
149  }
150
151  if (!file && !dir) {
152    fprintf(stderr, "Must specify either -F or -D\n");
153    usage();
154    exit(EXIT_FAILURE);
155  }
156
157  if (dir) {
158    pc = android_device_dirs;
159    end = &android_device_dirs[ARRAY_SIZE(android_device_dirs)];
160  } else {
161    pc = android_device_files;
162    end = &android_device_files[ARRAY_SIZE(android_device_files)];
163  }
164  for (; (pc < end) && pc->prefix; pc++) {
165    bool submit;
166    char buffer[512];
167    ssize_t len = fs_config_generate(buffer, sizeof(buffer), pc);
168    if (len < 0) {
169      fprintf(stderr, "Entry too large\n");
170      exit(EXIT_FAILURE);
171    }
172    submit = true;
173    if (partitions) {
174      char* partitions_copy = strdup(partitions);
175      char* arg = partitions_copy;
176      char* sv = NULL; /* Do not leave uninitialized, NULL is known safe. */
177      /* Deal with case all iterated partitions are blacklists with no match */
178      bool all_blacklist_but_no_match = true;
179      submit = false;
180
181      if (!partitions_copy) {
182        fprintf(stderr, "Failed to allocate a copy of %s\n", partitions);
183        exit(EXIT_FAILURE);
184      }
185      /* iterate through (officially) comma separated list of partitions */
186      while (!!(arg = strtok_r(arg, ",:; \t\n\r\f", &sv))) {
187        static const char system[] = "system/";
188        size_t plen;
189        bool blacklist = false;
190        if (*arg == '-') {
191          blacklist = true;
192          ++arg;
193        } else {
194          all_blacklist_but_no_match = false;
195        }
196        plen = strlen(arg);
197        /* deal with evil callers */
198        while (arg[plen - 1] == '/') {
199          --plen;
200        }
201        /* check if we have <partition>/ or /system/<partition>/ */
202        if ((!strncmp(pc->prefix, arg, plen) && (pc->prefix[plen] == '/')) ||
203            (!strncmp(pc->prefix, system, strlen(system)) &&
204             !strncmp(pc->prefix + strlen(system), arg, plen) &&
205             (pc->prefix[strlen(system) + plen] == '/'))) {
206          all_blacklist_but_no_match = false;
207          /* we have a match !!! */
208          if (!blacklist) submit = true;
209          break;
210        }
211        arg = NULL;
212      }
213      free(partitions_copy);
214      if (all_blacklist_but_no_match) submit = true;
215    }
216    if (submit && (fwrite(buffer, 1, len, fp) != (size_t)len)) {
217      fprintf(stderr, "Write failure\n");
218      exit(EXIT_FAILURE);
219    }
220  }
221  fclose(fp);
222
223  return 0;
224}
225