Will Drewry | 80fbc6c | 2010-08-30 10:13:34 -0500 | [diff] [blame] | 1 | /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| 2 | * Use of this source code is governed by a BSD-style license that can be |
| 3 | * found in the LICENSE file. |
| 4 | * |
| 5 | * Driver for using rootdev.c from the commandline |
| 6 | */ |
| 7 | #include <err.h> |
| 8 | #include <errno.h> |
| 9 | #include <getopt.h> |
| 10 | #include <linux/limits.h> |
| 11 | #include <stdbool.h> |
| 12 | #include <stdio.h> |
| 13 | #include <stdlib.h> |
| 14 | #include <string.h> |
| 15 | #include <sys/stat.h> |
| 16 | #include <sys/types.h> |
| 17 | #include <unistd.h> |
| 18 | |
| 19 | #include "rootdev.h" |
| 20 | |
| 21 | static void print_help(const char *progname) { |
| 22 | fprintf(stderr, |
| 23 | "%s [OPTIONS] [PATH]\n" |
| 24 | "Outputs the containing device for the specified PATH.\n" |
| 25 | "With no arguments, '/' is assumed.\n" |
| 26 | "\n" |
| 27 | "Options:\n" |
| 28 | " -h\tthis message.\n" |
| 29 | "\n" |
| 30 | " -c\tcreate the /dev node if it cannot be found\n" |
| 31 | " -d\treturn the block device only if possible\n" |
| 32 | " -i\treturn path even if the node doesn't exist\n" |
| 33 | " -s\tif possible, return the first slave of the root device\n" |
| 34 | "\n" |
| 35 | " --block [path]\tset the path to block under the sys mount point\n" |
| 36 | " --dev [path]\tset the path to dev mount point\n" |
| 37 | " --major [num]\tset the major number of the rootdev\n" |
| 38 | " --minor [num]\tset the minor number of the rootdev\n", |
| 39 | progname); |
| 40 | } |
| 41 | |
| 42 | static int flag_help = 0; |
| 43 | static int flag_use_slave = 0; |
| 44 | static int flag_strip_partition = 0; |
| 45 | static int flag_ignore = 0; |
| 46 | static int flag_create = 0; |
| 47 | static int flag_major = 0; |
| 48 | static int flag_minor = 0; |
| 49 | static const char *flag_path = "/"; |
| 50 | static char *flag_block_path = "/sys/block"; |
| 51 | static char *flag_dev_path = "/dev"; |
| 52 | |
| 53 | static void parse_args(int argc, char **argv) { |
| 54 | while (1) { |
| 55 | int c; |
| 56 | int option_index = 0; |
| 57 | static const struct option long_options[] = { |
| 58 | {"c", no_argument, &flag_create, 1}, |
| 59 | {"d", no_argument, &flag_strip_partition, 1}, |
| 60 | {"h", no_argument, &flag_help, 1}, |
| 61 | {"i", no_argument, &flag_ignore, 1}, |
| 62 | {"s", no_argument, &flag_use_slave, 1}, |
| 63 | /* Long arguments for testing. */ |
| 64 | {"block", required_argument, NULL, 'b'}, |
| 65 | {"dev", required_argument, NULL, 'd'}, |
| 66 | {"major", required_argument, NULL, 'M'}, |
| 67 | {"minor", required_argument, NULL, 'm'}, |
| 68 | {0, 0, 0, 0} |
| 69 | }; |
| 70 | c = getopt_long_only(argc, argv, "", long_options, &option_index); |
| 71 | |
| 72 | if (c == -1) |
| 73 | break; |
| 74 | |
| 75 | if (c == '?') { |
| 76 | flag_help = 1; |
| 77 | break; |
| 78 | } |
| 79 | |
| 80 | switch (c) { |
| 81 | case 'b': |
| 82 | flag_block_path = optarg; |
| 83 | break; |
| 84 | case 'd': |
| 85 | flag_dev_path = optarg; |
| 86 | break; |
| 87 | case 'M': |
| 88 | flag_major = atoi(optarg); |
| 89 | break; |
| 90 | case 'm': |
| 91 | flag_minor = atoi(optarg); |
| 92 | break; |
| 93 | } |
| 94 | |
| 95 | } |
| 96 | |
| 97 | if (flag_create && flag_strip_partition) { |
| 98 | flag_help = 1; |
| 99 | warnx("-c and -d are incompatible at present."); |
| 100 | return; |
| 101 | } |
| 102 | |
| 103 | if (optind < argc) { |
| 104 | flag_path = argv[optind++]; |
| 105 | } |
| 106 | |
| 107 | if (optind < argc) { |
| 108 | fprintf(stderr, "Too many free arguments: %d\n", argc - optind); |
| 109 | flag_help = 1; |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | int main(int argc, char **argv) { |
| 114 | struct stat path_stat; |
| 115 | char path[PATH_MAX]; |
| 116 | int ret; |
| 117 | dev_t root_dev; |
| 118 | parse_args(argc, argv); |
| 119 | |
| 120 | if (flag_help) { |
| 121 | print_help(argv[0]); |
| 122 | return 1; |
| 123 | } |
| 124 | |
| 125 | if (flag_major || flag_minor) { |
| 126 | root_dev = makedev(flag_major, flag_minor); |
| 127 | } else { |
| 128 | /* Yields the containing dev_t in st_dev. */ |
| 129 | if (stat(flag_path, &path_stat) != 0) |
| 130 | err(1, "Cannot stat(%s)", flag_path); |
| 131 | root_dev = path_stat.st_dev; |
| 132 | } |
| 133 | |
Mike Frysinger | 32979f6 | 2014-12-11 23:00:55 -0500 | [diff] [blame^] | 134 | path[0] = '\0'; |
Will Drewry | 80fbc6c | 2010-08-30 10:13:34 -0500 | [diff] [blame] | 135 | ret = rootdev_wrapper(path, sizeof(path), |
| 136 | flag_use_slave, |
| 137 | flag_strip_partition, |
| 138 | &root_dev, |
| 139 | flag_block_path, |
| 140 | flag_dev_path); |
| 141 | |
| 142 | if (ret == 1 && flag_create) { |
| 143 | /* TODO(wad) add flag_force to allow replacement */ |
| 144 | ret = 0; |
| 145 | if (mknod(path, S_IFBLK | S_IRUSR | S_IWUSR, root_dev) && errno != EEXIST) { |
| 146 | warn("failed to create %s", path); |
| 147 | ret = 1; |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | if (flag_ignore && ret > 0) |
| 152 | ret = 0; |
| 153 | |
| 154 | if (path[0] != '\0') |
| 155 | printf("%s\n", path); |
| 156 | |
| 157 | return ret; |
| 158 | } |