blkid: add -n <list> option

This option allows to restrict low-level probing to the defined list
of superbocks (filesystems or RAIDs). For example:

	blkid -p -n ext3,ext4,vfat /dev/sda1
or
	blkid -p -n novfat /dev/sda1

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/blkid.8 b/misc-utils/blkid.8
index 9419da0f8abd74d02321f7fb9409762038a506cf..ea78d246be50263e3203452b70b175cb029a725c 100644 (file)
--- a/misc-utils/blkid.8
+++ b/misc-utils/blkid.8
@@ -43,6 +43,8 @@ blkid \- command\-line utility to locate/print block device attributes
 .RB [ \-s
 .IR tag ]
 .in +9
+.RB [ \-n
+.IR list ]
 .RB [ \-u
 .IR list ]
 .I device
@@ -104,6 +106,21 @@ from e2fsprogs use the \fB-L\fR option as a
 synonym to the \fB-o list\fR option. For better portability use "-l -o device
 -t LABEL=<label>" and "-o list" in your scripts rather than -L option.
 .TP
+.B \-n " list "
+Restrict probing functions to defined (comma separated) list of superblock types (names).
+The list can be prefixed with "no" to specify the types which should be ignored.
+For example:
+.sp
+  blkid -p -n vfat,ext3,ext4 /dev/sda1
+.sp
+probes for vfat, ext3 and ext4 filesystems, and
+.sp
+  blkid -p -u nominix /dev/sda1
+.sp
+probes for all supported formats exclude minix filesystem. This option is
+useful with
+\fB-p\fR only.
+.TP
 .B \-u " list "
 Restrict probing functions to defined (comma separated) list of "usage" types.
 Supported usage types are: filesystem, raid, crypto and other. The list can be

diff --git a/misc-utils/blkid.c b/misc-utils/blkid.c
index b2d231bc7330e6a475d9a3d807813b8ab3cc49db..653af035774effe9dde969eaf8201783dd33c9e9 100644 (file)
--- a/misc-utils/blkid.c
+++ b/misc-utils/blkid.c
@@ -76,6 +76,7 @@ static void usage(int error)
                "  -S <bytes>  overwrite device size\n"
                "  -O <bytes>  probe at the given offset\n"
                "  -u <list>   filter by \"usage\" (e.g. -u filesystem,raid)\n"
+               "  -n <list>   filter by filesystem type (e.g. -n vfat,ext3)\n"
                "\n",
                                progname);
 
@@ -532,17 +533,13 @@ static int list_to_usage(const char *list, int *flag)
                *flag = BLKID_FLTR_NOTIN;
                p += 2;
        }
-
        if (!p || !*p)
                goto err;
-
        while(p) {
                word = p;
-
                p = strchr(p, ',');
                if (p)
                        p++;
-
                if (!strncmp(word, "filesystem", 10))
                        mask |= BLKID_USAGE_FILESYSTEM;
                else if (!strncmp(word, "raid", 4))
@@ -555,7 +552,6 @@ static int list_to_usage(const char *list, int *flag)
                        goto err;
        }
        return mask;
-
 err:
        *flag = 0;
        fprintf(stderr, "unknown kerword in -u <list> argument: '%s'\n",
@@ -563,6 +559,59 @@ err:
        exit(4);
 }
 
+/* converts comma separated list to types[] */
+static char **list_to_types(const char *list, int *flag)
+{
+       int i;
+       const char *p = list;
+       char **res;
+
+       if (p && strncmp(p, "no", 2) == 0) {
+               *flag = BLKID_FLTR_NOTIN;
+               p += 2;
+       }
+       if (!p || !*p) {
+               fprintf(stderr, "error: -u <list> argument is empty\n");
+               goto err;
+       }
+       for (i = 1; p && (p = strchr(p, ',')); i++, p++);
+
+       res = calloc(i + 1, sizeof(char *));
+       if (!res)
+               goto err_mem;
+       p = *flag & BLKID_FLTR_NOTIN ? list + 2 : list;
+       i = 0;
+
+       while(p) {
+               const char *word = p;
+               p = strchr(p, ',');
+               res[i] = p ? strndup(word, p - word) : strdup(word);
+               if (!res[i++])
+                       goto err_mem;
+               if (p)
+                       p++;
+       }
+       res[i] = NULL;
+       return res;
+err_mem:
+       fprintf(stderr, "out of memory\n");
+err:
+       *flag = 0;
+       free(res);
+       exit(4);
+}
+
+static void free_types_list(char *list[])
+{
+       char **n;
+
+       if (!list)
+               return;
+       for (n = list; *n; n++)
+               free(*n);
+       free(list);
+}
+
 int main(int argc, char **argv)
 {
        blkid_cache cache = NULL;
@@ -572,6 +621,7 @@ int main(int argc, char **argv)
        char *read = NULL;
        char *write = NULL;
        int fltr_usage = 0;
+       char **fltr_type = NULL;
        int fltr_flag = BLKID_FLTR_ONLYIN;
        unsigned int numdev = 0, numtag = 0;
        int version = 0;
@@ -584,7 +634,7 @@ int main(int argc, char **argv)
 
        show[0] = NULL;
 
-       while ((c = getopt (argc, argv, "c:f:ghlL:o:O:ps:S:t:u:U:w:v")) != EOF)
+       while ((c = getopt (argc, argv, "c:f:ghlL:n:o:O:ps:S:t:u:U:w:v")) != EOF)
                switch (c) {
                case 'c':
                        if (optarg && !*optarg)
@@ -599,7 +649,18 @@ int main(int argc, char **argv)
                        search_value = strdup(optarg);
                        search_type = strdup("LABEL");
                        break;
+               case 'n':
+                       if (fltr_usage) {
+                               fprintf(stderr, "error: -u and -n options are mutually exclusive\n");
+                               exit(4);
+                       }
+                       fltr_type = list_to_types(optarg, &fltr_flag);
+                       break;
                case 'u':
+                       if (fltr_type) {
+                               fprintf(stderr, "error: -u and -n options are mutually exclusive\n");
+                               exit(4);
+                       }
                        fltr_usage = list_to_usage(optarg, &fltr_flag);
                        break;
                case 'U':
@@ -733,6 +794,9 @@ int main(int argc, char **argv)
                if (fltr_usage &&
                    blkid_probe_filter_superblocks_usage(pr, fltr_flag, fltr_usage))
                        goto exit;
+               else if (fltr_type &&
+                   blkid_probe_filter_superblocks_type(pr, fltr_flag, fltr_type))
+                       goto exit;
 
                for (i = 0; i < numdev; i++)
                        err = lowprobe_device(pr, devices[i], show,
@@ -802,6 +866,7 @@ int main(int argc, char **argv)
 exit:
        free(search_type);
        free(search_value);
+       free_types_list(fltr_type);
        if (!lowprobe && !eval)
                blkid_put_cache(cache);
        return err;