extras/fstab_import/fstab_import.c

   1 /*
   2  * find matching entry in fstab and export it
   3  *
   4  * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #ifndef _GNU_SOURCE
  13 #define _GNU_SOURCE 1
  14 #endif
  15
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <unistd.h>
  19 #include <fcntl.h>
  20 #include <ctype.h>
  21 #include <string.h>
  22 #include <errno.h>
  23 #include <getopt.h>
  24 #include <mntent.h>
  25 #include <sys/stat.h>
  26
  27 #include "../../udev/udev.h"
  28
  29 static int debug;
  30
  31 static void log_fn(struct udev *udev, int priority,
  32                    const char *file, int line, const char *fn,
  33                    const char *format, va_list args)
  34 {
  35         if (debug) {
  36                 fprintf(stderr, "%s: ", fn);
  37                 vfprintf(stderr, format, args);
  38         } else {
  39                 vsyslog(priority, format, args);
  40         }
  41 }
  42
  43 static int matches_device_list(struct udev *udev, char **devices, const char *name)
  44 {
  45         int i;
  46
  47         for (i = 0; devices[i] != NULL; i++) {
  48                 info(udev, "compare '%s' == '%s'\n", name, devices[i]);
  49                 if (strcmp(devices[i], name) == 0)
  50                         return 1;
  51         }
  52         return 0;
  53 }
  54
  55 static void print_fstab_entry(struct udev *udev, struct mntent *mnt)
  56 {
  57         printf("FSTAB_NAME=%s\n", mnt->mnt_fsname);
  58         printf("FSTAB_DIR=%s\n", mnt->mnt_dir);
  59         printf("FSTAB_TYPE=%s\n", mnt->mnt_type);
  60         printf("FSTAB_OPTS=%s\n", mnt->mnt_opts);
  61         printf("FSTAB_FREQ=%d\n", mnt->mnt_freq);
  62         printf("FSTAB_PASSNO=%d\n", mnt->mnt_passno);
  63 }
  64
  65 int main(int argc, char *argv[])
  66 {
  67         struct udev *udev;
  68         static const struct option options[] = {
  69                 { "export", no_argument, NULL, 'x' },
  70                 { "debug", no_argument, NULL, 'd' },
  71                 { "help", no_argument, NULL, 'h' },
  72                 {}
  73         };
  74         char **devices;
  75         FILE *fp;
  76         struct mntent *mnt;
  77         int rc = 1;
  78
  79         udev = udev_new();
  80         if (udev == NULL)
  81                 goto exit;
  82
  83         logging_init("fstab_id");
  84         udev_set_log_fn(udev, log_fn);
  85
  86         while (1) {
  87                 int option;
  88
  89                 option = getopt_long(argc, argv, "dxh", options, NULL);
  90                 if (option == -1)
  91                         break;
  92
  93                 switch (option) {
  94                 case 'd':
  95                         debug = 1;
  96                         if (udev_get_log_priority(udev) < LOG_INFO)
  97                                 udev_set_log_priority(udev, LOG_INFO);
  98                         break;
  99                 case 'h':
 100                         printf("Usage: fstab_id [OPTIONS] name [...]\n"
 101                                "  --export        print environment keys\n"
 102                                "  --debug         debug to stderr\n"
 103                                "  --help          print this help text\n\n");
 104                         goto exit;
 105                 case 'x':
 106                         break;
 107                 default:
 108                         rc = 2;
 109                         goto exit;
 110                 }
 111         }
 112
 113         devices = &argv[optind];
 114         if (devices[0] == NULL) {
 115                 fprintf(stderr, "error: missing device(s) to match\n");
 116                 rc = 3;
 117                 goto exit;
 118         }
 119
 120         fp = setmntent ("/etc/fstab", "r");
 121         if (fp == NULL) {
 122                 fprintf(stderr, "error: opening fstab: %s\n", strerror(errno));
 123                 rc = 4;
 124                 goto exit;
 125         }
 126
 127         while (1) {
 128                 mnt = getmntent(fp);
 129                 if (mnt == NULL)
 130                         break;
 131
 132                 info(udev, "found '%s'@'%s'\n", mnt->mnt_fsname, mnt->mnt_dir);
 133
 134                 /* skip root device */
 135                 if (strcmp(mnt->mnt_dir, "/") == 0)
 136                         continue;
 137
 138                 /* match LABEL */
 139                 if (strncmp(mnt->mnt_fsname, "LABEL=", 6) == 0) {
 140                         const char *label;
 141                         char str[256];
 142
 143                         label = &mnt->mnt_fsname[6];
 144                         if (label[0] == '"' || label[0] == '\'') {
 145                                 char *pos;
 146
 147                                 util_strlcpy(str, &label[1], sizeof(str));
 148                                 pos = strrchr(str, label[0]);
 149                                 if (pos == NULL)
 150                                         continue;
 151                                 pos[0] = '\0';
 152                                 label = str;
 153                         }
 154                         if (matches_device_list(udev, devices, str)) {
 155                                 print_fstab_entry(udev, mnt);
 156                                 rc = 0;
 157                                 break;
 158                         }
 159                         continue;
 160                 }
 161
 162                 /* match UUID */
 163                 if (strncmp(mnt->mnt_fsname, "UUID=", 5) == 0) {
 164                         const char *uuid;
 165                         char str[256];
 166
 167                         uuid = &mnt->mnt_fsname[5];
 168                         if (uuid[0] == '"' || uuid[0] == '\'') {
 169                                 char *pos;
 170
 171                                 util_strlcpy(str, &uuid[1], sizeof(str));
 172                                 pos = strrchr(str, uuid[0]);
 173                                 if (pos == NULL)
 174                                         continue;
 175                                 pos[0] = '\0';
 176                                 uuid = str;
 177                         }
 178                         if (matches_device_list(udev, devices, str)) {
 179                                 print_fstab_entry(udev, mnt);
 180                                 rc = 0;
 181                                 break;
 182                         }
 183                         continue;
 184                 }
 185
 186                 /* only devices */
 187                 if (strncmp(mnt->mnt_fsname, udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) != 0)
 188                         continue;
 189
 190                 if (matches_device_list(udev, devices, &mnt->mnt_fsname[strlen(udev_get_dev_path(udev))+1])) {
 191                         print_fstab_entry(udev, mnt);
 192                         rc = 0;
 193                         break;
 194                 }
 195         }
 196         endmntent(fp);
 197
 198 exit:
 199         udev_unref(udev);
 200         logging_close();
 201         return rc;
 202 }