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 "libudev.h"
  28 #include "libudev-private.h"
  29
  30 static int debug;
  31
  32 static void log_fn(struct udev *udev, int priority,
  33                    const char *file, int line, const char *fn,
  34                    const char *format, va_list args)
  35 {
  36         if (debug) {
  37                 fprintf(stderr, "%s: ", fn);
  38                 vfprintf(stderr, format, args);
  39         } else {
  40                 vsyslog(priority, format, args);
  41         }
  42 }
  43
  44 static int matches_device_list(struct udev *udev, char **devices, const char *name)
  45 {
  46         int i;
  47
  48         for (i = 0; devices[i] != NULL; i++) {
  49                 info(udev, "compare '%s' == '%s'\n", name, devices[i]);
  50                 if (strcmp(devices[i], name) == 0)
  51                         return 1;
  52         }
  53         return 0;
  54 }
  55
  56 static void print_fstab_entry(struct udev *udev, struct mntent *mnt)
  57 {
  58         printf("FSTAB_NAME=%s\n", mnt->mnt_fsname);
  59         printf("FSTAB_DIR=%s\n", mnt->mnt_dir);
  60         printf("FSTAB_TYPE=%s\n", mnt->mnt_type);
  61         printf("FSTAB_OPTS=%s\n", mnt->mnt_opts);
  62         printf("FSTAB_FREQ=%d\n", mnt->mnt_freq);
  63         printf("FSTAB_PASSNO=%d\n", mnt->mnt_passno);
  64 }
  65
  66 int main(int argc, char *argv[])
  67 {
  68         struct udev *udev;
  69         static const struct option options[] = {
  70                 { "export", no_argument, NULL, 'x' },
  71                 { "debug", no_argument, NULL, 'd' },
  72                 { "help", no_argument, NULL, 'h' },
  73                 {}
  74         };
  75         char **devices;
  76         FILE *fp;
  77         struct mntent *mnt;
  78         int rc = 1;
  79
  80         udev = udev_new();
  81         if (udev == NULL)
  82                 goto exit;
  83
  84         udev_log_init("fstab_id");
  85         udev_set_log_fn(udev, log_fn);
  86
  87         while (1) {
  88                 int option;
  89
  90                 option = getopt_long(argc, argv, "dxh", options, NULL);
  91                 if (option == -1)
  92                         break;
  93
  94                 switch (option) {
  95                 case 'd':
  96                         debug = 1;
  97                         if (udev_get_log_priority(udev) < LOG_INFO)
  98                                 udev_set_log_priority(udev, LOG_INFO);
  99                         break;
 100                 case 'h':
 101                         printf("Usage: fstab_id [OPTIONS] name [...]\n"
 102                                "  --export        print environment keys\n"
 103                                "  --debug         debug to stderr\n"
 104                                "  --help          print this help text\n\n");
 105                         goto exit;
 106                 case 'x':
 107                         break;
 108                 default:
 109                         rc = 2;
 110                         goto exit;
 111                 }
 112         }
 113
 114         devices = &argv[optind];
 115         if (devices[0] == NULL) {
 116                 fprintf(stderr, "error: missing device(s) to match\n");
 117                 rc = 3;
 118                 goto exit;
 119         }
 120
 121         fp = setmntent ("/etc/fstab", "r");
 122         if (fp == NULL) {
 123                 fprintf(stderr, "error: opening fstab: %s\n", strerror(errno));
 124                 rc = 4;
 125                 goto exit;
 126         }
 127
 128         while (1) {
 129                 mnt = getmntent(fp);
 130                 if (mnt == NULL)
 131                         break;
 132
 133                 info(udev, "found '%s'@'%s'\n", mnt->mnt_fsname, mnt->mnt_dir);
 134
 135                 /* skip root device */
 136                 if (strcmp(mnt->mnt_dir, "/") == 0)
 137                         continue;
 138
 139                 /* match LABEL */
 140                 if (strncmp(mnt->mnt_fsname, "LABEL=", 6) == 0) {
 141                         const char *label;
 142                         char str[256];
 143
 144                         label = &mnt->mnt_fsname[6];
 145                         if (label[0] == '"' || label[0] == '\'') {
 146                                 char *pos;
 147
 148                                 util_strscpy(str, sizeof(str), &label[1]);
 149                                 pos = strrchr(str, label[0]);
 150                                 if (pos == NULL)
 151                                         continue;
 152                                 pos[0] = '\0';
 153                                 label = str;
 154                         }
 155                         if (matches_device_list(udev, devices, str)) {
 156                                 print_fstab_entry(udev, mnt);
 157                                 rc = 0;
 158                                 break;
 159                         }
 160                         continue;
 161                 }
 162
 163                 /* match UUID */
 164                 if (strncmp(mnt->mnt_fsname, "UUID=", 5) == 0) {
 165                         const char *uuid;
 166                         char str[256];
 167
 168                         uuid = &mnt->mnt_fsname[5];
 169                         if (uuid[0] == '"' || uuid[0] == '\'') {
 170                                 char *pos;
 171
 172                                 util_strscpy(str, sizeof(str), &uuid[1]);
 173                                 pos = strrchr(str, uuid[0]);
 174                                 if (pos == NULL)
 175                                         continue;
 176                                 pos[0] = '\0';
 177                                 uuid = str;
 178                         }
 179                         if (matches_device_list(udev, devices, str)) {
 180                                 print_fstab_entry(udev, mnt);
 181                                 rc = 0;
 182                                 break;
 183                         }
 184                         continue;
 185                 }
 186
 187                 /* only devices */
 188                 if (strncmp(mnt->mnt_fsname, udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) != 0)
 189                         continue;
 190
 191                 if (matches_device_list(udev, devices, &mnt->mnt_fsname[strlen(udev_get_dev_path(udev))+1])) {
 192                         print_fstab_entry(udev, mnt);
 193                         rc = 0;
 194                         break;
 195                 }
 196         }
 197         endmntent(fp);
 198
 199 exit:
 200         udev_unref(udev);
 201         udev_log_close();
 202         return rc;
 203 }