Add more description in mke2fs's man page of the -T option

[tools/e2fsprogs.git] / misc / blkid.c

diff --git a/misc/blkid.c b/misc/blkid.c
index ecbf8cf..256f4f1 100644 (file)
--- a/misc/blkid.c
+++ b/misc/blkid.c
@@ -37,12 +37,13 @@ static void usage(int error)
 
        print_version(out);
        fprintf(out,
-               "usage:\t%s [-c <file>] [-h] [-o format] "
+               "usage:\t%s [-c <file>] [-hl] [-o format] "
                "[-s <tag>] [-t <token>]\n    [-v] [-w <file>] [dev ...]\n"
                "\t-c\tcache file (default: /etc/blkid.tab, /dev/null = none)\n"
                "\t-h\tprint this usage message and exit\n"
                "\t-s\tshow specified tag(s) (default show all tags)\n"
                "\t-t\tfind device with a specific token (NAME=value pair)\n"
+               "\t-l\tlookup the the first device with arguments specified by -t\n"
                "\t-v\tprint version and exit\n"
                "\t-w\twrite cache to different file (/dev/null = no write)\n"
                "\tdev\tspecify device(s) to probe (default: all devices)\n",
@@ -88,26 +89,6 @@ static void print_tags(blkid_dev dev, char *show[], int numtag, int output)
                printf("\n");
 }
 
-int compare_search_type(blkid_dev dev, const char *search_type, 
-                       const char *search_value)
-{
-       blkid_tag_iterate       tag_iter;
-       const char              *type, *value;
-       int                     found = 0;
-
-       tag_iter = blkid_tag_iterate_begin(dev);
-       while (blkid_tag_next(tag_iter, &type, &value) == 0) {
-               if (!strcmp(type, search_type) &&
-                   !strcmp(value, search_value)) {
-                       found++;
-                       break;
-               }
-       }
-       blkid_tag_iterate_end(tag_iter);
-
-       return found;
-}
-
 int main(int argc, char **argv)
 {
        blkid_cache cache = NULL;
@@ -121,9 +102,10 @@ int main(int argc, char **argv)
        int err = 4;
        unsigned int i;
        int output_format = 0;
-       char c;
+       int lookup = 0;
+       int c;
 
-       while ((c = getopt (argc, argv, "c:f:ho:s:t:w:v")) != EOF)
+       while ((c = getopt (argc, argv, "c:f:hlo:s:t:w:v")) != EOF)
                switch (c) {
                case 'c':
                        if (optarg && !*optarg)
@@ -133,6 +115,9 @@ int main(int argc, char **argv)
                        if (!write)
                                write = read;
                        break;
+               case 'l':
+                       lookup++;
+                       break;
                case 'o':
                        if (!strcmp(optarg, "value"))
                                output_format = OUTPUT_VALUE_ONLY;
@@ -192,22 +177,36 @@ int main(int argc, char **argv)
                goto exit;
 
        err = 2;
+       if (lookup) {
+               blkid_dev dev;
+
+               if (!search_type) {
+                       fprintf(stderr, "The lookup option requires a "
+                               "search type specified using -t\n");
+                       exit(1);
+               }
+               /* Load any additional devices not in the cache */
+               for (i = 0; i < numdev; i++)
+                       blkid_get_dev(cache, devices[i], BLKID_DEV_NORMAL);
+
+               if ((dev = blkid_find_dev_with_tag(cache, search_type,
+                                                  search_value))) {
+                       print_tags(dev, show, numtag, output_format);
+                       err = 0;
+               }
        /* If we didn't specify a single device, show all available devices */
-       if (!numdev) {
+       } else if (!numdev) {
                blkid_dev_iterate       iter;
                blkid_dev               dev;
 
                blkid_probe_all(cache);
 
                iter = blkid_dev_iterate_begin(cache);
+               blkid_dev_set_search(iter, search_type, search_value);
                while (blkid_dev_next(iter, &dev) == 0) {
                        dev = blkid_verify(cache, dev);
                        if (!dev)
                                continue;
-                       if (search_type &&
-                           !compare_search_type(dev, search_type, 
-                                                search_value))
-                               continue;
                        print_tags(dev, show, numtag, output_format);
                        err = 0;
                }
@@ -218,9 +217,9 @@ int main(int argc, char **argv)
                                                  BLKID_DEV_NORMAL);
 
                if (dev) {
-                       if (search_type &&
-                           !compare_search_type(dev, search_type, 
-                                                search_value))
+                       if (search_type && 
+                           !blkid_dev_has_tag(dev, search_type, 
+                                              search_value))
                                continue;
                        print_tags(dev, show, numtag, output_format);
                        err = 0;