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 "config.h"
  17
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <unistd.h>
  21 #include <fcntl.h>
  22 #include <ctype.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <getopt.h>
  26 #include <mntent.h>
  27 #include <sys/stat.h>
  28
  29 #include "../../udev/udev.h"
  30
  31 static int debug;
  32
  33 static void log_fn(struct udev *udev, int priority,
  34                    const char *file, int line, const char *fn,
  35                    const char *format, va_list args)
  36 {
  37         if (debug) {
  38                 fprintf(stderr, "%s: ", fn);
  39                 vfprintf(stderr, format, args);
  40         } else {
  41                 vsyslog(priority, format, args);
  42         }
  43 }
  44
  45 static int matches_device_list(struct udev *udev, char **devices, const char *name)
  46 {
  47         int i;
  48
  49         for (i = 0; devices[i] != NULL; i++) {
  50                 info(udev, "compare '%s' == '%s'\n", name, devices[i]);
  51                 if (strcmp(devices[i], name) == 0)
  52                         return 1;
  53         }
  54         return 0;
  55 }
  56
  57 static void print_fstab_entry(struct udev *udev, struct mntent *mnt)
  58 {
  59         printf("FSTAB_NAME=%s\n", mnt->mnt_fsname);
  60         printf("FSTAB_DIR=%s\n", mnt->mnt_dir);
  61         printf("FSTAB_TYPE=%s\n", mnt->mnt_type);
  62         printf("FSTAB_OPTS=%s\n", mnt->mnt_opts);
  63         printf("FSTAB_FREQ=%d\n", mnt->mnt_freq);
  64         printf("FSTAB_PASSNO=%d\n", mnt->mnt_passno);
  65 }
  66
  67 int main(int argc, char *argv[])
  68 {
  69         struct udev *udev;
  70         static const struct option options[] = {
  71                 { "export", 0, NULL, 'x' },
  72                 { "debug", 0, NULL, 'd' },
  73                 { "help", 0, NULL, 'h' },
  74                 {}
  75         };
  76         char **devices;
  77         FILE *fp;
  78         struct mntent *mnt;
  79         int rc = 1;
  80
  81         udev = udev_new();
  82         if (udev == NULL)
  83                 goto exit;
  84
  85         logging_init("fstab_id");
  86         udev_set_log_fn(udev, log_fn);
  87
  88         while (1) {
  89                 int option;
  90
  91                 option = getopt_long(argc, argv, "dxh", options, NULL);
  92                 if (option == -1)
  93                         break;
  94
  95                 switch (option) {
  96                 case 'd':
  97                         debug = 1;
  98                         if (udev_get_log_priority(udev) < LOG_INFO)
  99                                 udev_set_log_priority(udev, LOG_INFO);
 100                         break;
 101                 case 'h':
 102                         printf("Usage: fstab_id [OPTIONS] name [...]\n"
 103                                "  --export        print environment keys\n"
 104                                "  --debug         debug to stderr\n"
 105                                "  --help          print this help text\n\n");
 106                         goto exit;
 107                 case 'x':
 108                         break;
 109                 default:
 110                         rc = 2;
 111                         goto exit;
 112                 }
 113         }
 114
 115         devices = &argv[optind];
 116         if (devices[0] == NULL) {
 117                 fprintf(stderr, "error: missing device(s) to match\n");
 118                 rc = 3;
 119                 goto exit;
 120         }
 121
 122         fp = setmntent ("/etc/fstab", "r");
 123         if (fp == NULL) {
 124                 fprintf(stderr, "error: opening fstab: %s\n", strerror(errno));
 125                 rc = 4;
 126                 goto exit;
 127         }
 128
 129         while (1) {
 130                 mnt = getmntent(fp);
 131                 if (mnt == NULL)
 132                         break;
 133
 134                 info(udev, "found '%s'@'%s'\n", mnt->mnt_fsname, mnt->mnt_dir);
 135
 136                 /* skip root device */
 137                 if (strcmp(mnt->mnt_dir, "/") == 0)
 138                         continue;
 139
 140                 /* match LABEL */
 141                 if (strncmp(mnt->mnt_fsname, "LABEL=", 6) == 0) {
 142                         const char *label;
 143                         char str[256];
 144
 145                         label = &mnt->mnt_fsname[6];
 146                         if (label[0] == '"' || label[0] == '\'') {
 147                                 char *pos;
 148
 149                                 strlcpy(str, &label[1], sizeof(str));
 150                                 pos = strrchr(str, label[0]);
 151                                 if (pos == NULL)
 152                                         continue;
 153                                 pos[0] = '\0';
 154                                 label = str;
 155                         }
 156                         if (matches_device_list(udev, devices, str)) {
 157                                 print_fstab_entry(udev, mnt);
 158                                 rc = 0;
 159                                 break;
 160                         }
 161                         continue;
 162                 }
 163
 164                 /* match UUID */
 165                 if (strncmp(mnt->mnt_fsname, "UUID=", 5) == 0) {
 166                         const char *uuid;
 167                         char str[256];
 168
 169                         uuid = &mnt->mnt_fsname[5];
 170                         if (uuid[0] == '"' || uuid[0] == '\'') {
 171                                 char *pos;
 172
 173                                 strlcpy(str, &uuid[1], sizeof(str));
 174                                 pos = strrchr(str, uuid[0]);
 175                                 if (pos == NULL)
 176                                         continue;
 177                                 pos[0] = '\0';
 178                                 uuid = str;
 179                         }
 180                         if (matches_device_list(udev, devices, str)) {
 181                                 print_fstab_entry(udev, mnt);
 182                                 rc = 0;
 183                                 break;
 184                         }
 185                         continue;
 186                 }
 187
 188                 /* only devices */
 189                 if (strncmp(mnt->mnt_fsname, udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) != 0)
 190                         continue;
 191
 192                 if (matches_device_list(udev, devices, &mnt->mnt_fsname[strlen(udev_get_dev_path(udev))+1])) {
 193                         print_fstab_entry(udev, mnt);
 194                         rc = 0;
 195                         break;
 196                 }
 197         }
 198         endmntent(fp);
 199
 200 exit:
 201         udev_unref(udev);
 202         logging_close();
 203         return rc;
 204 }