blkid.c (main, print_tags): Add new option -o which allows the

		user to control the output format of blkid.

diff --git a/misc/ChangeLog b/misc/ChangeLog
index 91d26ef..9ba40fb 100644 (file)
--- a/misc/ChangeLog
+++ b/misc/ChangeLog
@@ -1,5 +1,8 @@
 2004-03-20  Theodore Ts'o  <tytso@mit.edu>
 
+       * blkid.c (main, print_tags): Add new option -o which allows the
+               user to control the output format of blkid.
+
        * mke2fs.8.in: Fix spelling typos (Addresses Debian Bug #238741)
 
 2004-03-08  Theodore Ts'o  <tytso@mit.edu>

diff --git a/misc/blkid.8.in b/misc/blkid.8.in
index b39a6bb..6a4ca2d 100644 (file)
--- a/misc/blkid.8.in
+++ b/misc/blkid.8.in
@@ -22,6 +22,10 @@ blkid \- command\-line utility to locate/print block device attributes
 .I writecachefile
 ]
 [
+.B \-o
+.I format
+]
+[
 .B \-s
 .I tag
 ]
@@ -59,6 +63,21 @@ scanned but not necessarily available at this time), specify
 .B \-h
 Display a usage message and exit.
 .TP
+.B \-o 
+Display 
+.BR blkid 's
+output using the specified format.  The
+.I format
+parameter may be 
+.IR full ,
+(the default), 
+.IR  value ,
+(only print the value of any tags printed by 
+.BR blkid)
+or 
+.I device
+(only print the device name).
+.TP
 .B \-p
 Probe all available devices.  This is the default when displaying
 tokens.  When searching for a token normally the cache file is

diff --git a/misc/blkid.c b/misc/blkid.c
index 9caebbd..c529b07 100644 (file)
--- a/misc/blkid.c
+++ b/misc/blkid.c
@@ -19,6 +19,9 @@ extern char *optarg;
 extern int optind;
 #endif
 
+#define OUTPUT_VALUE_ONLY      0x0001
+#define OUTPUT_DEVICE_ONLY     0x0002
+
 #include "blkid/blkid.h"
 
 const char *progname = "blkid";
@@ -34,8 +37,8 @@ static void usage(int error)
 
        print_version(out);
        fprintf(out,
-               "usage:\t%s [-c <file>] [-h] "
-               "[-p] [-s <tag>] [-t <token>] [-v] [-w <file>] [dev ...]\n"
+               "usage:\t%s [-c <file>] [-h] [-o format] "
+               "[-p] [-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"
@@ -47,7 +50,7 @@ static void usage(int error)
        exit(error);
 }
 
-static void print_tags(blkid_dev dev, char *show[], int numtag)
+static void print_tags(blkid_dev dev, char *show[], int numtag, int output)
 {
        blkid_tag_iterate       iter;
        const char              *type, *value;
@@ -56,6 +59,11 @@ static void print_tags(blkid_dev dev, char *show[], int numtag)
        if (!dev)
                return;
 
+       if (output & OUTPUT_DEVICE_ONLY) {
+               printf("%s\n", blkid_dev_devname(dev));
+               return;
+       }
+
        iter = blkid_tag_iterate_begin(dev);
        while (blkid_tag_next(iter, &type, &value) == 0) {
                if (numtag && show) {
@@ -65,15 +73,18 @@ static void print_tags(blkid_dev dev, char *show[], int numtag)
                        if (i >= numtag)
                                continue;
                }
-               if (first) {
+               if (first && !(output & OUTPUT_VALUE_ONLY)) {
                        printf("%s: ", blkid_dev_devname(dev));
                        first = 0;
                }
-               printf("%s=\"%s\" ", type, value);
+               if ((output & OUTPUT_VALUE_ONLY))
+                       printf("%s\n", value);
+               else
+                       printf("%s=\"%s\" ", type, value);
        }
        blkid_tag_iterate_end(iter);
 
-       if (!first)
+       if (!first && !(output & OUTPUT_VALUE_ONLY))
                printf("\n");
 }
 
@@ -89,9 +100,10 @@ int main(int argc, char **argv)
        int version = 0;
        int err = 4;
        unsigned int i;
+       int output_format = 0;
        char c;
 
-       while ((c = getopt (argc, argv, "c:f:hps:t:w:v")) != EOF)
+       while ((c = getopt (argc, argv, "c:f:ho:ps:t:w:v")) != EOF)
                switch (c) {
                case 'c':
                        if (optarg && !*optarg)
@@ -101,6 +113,18 @@ int main(int argc, char **argv)
                        if (!write)
                                write = read;
                        break;
+               case 'o':
+                       if (!strcmp(optarg, "value"))
+                               output_format = OUTPUT_VALUE_ONLY;
+                       else if (!strcmp(optarg, "device"))
+                               output_format = OUTPUT_DEVICE_ONLY;
+                       else if (!strcmp(optarg, "full"))
+                               output_format = 0;
+                       else {
+                               fprintf(stderr, "Invalid output format %s.  Chose from value, device, or full\n", optarg);
+                               exit(1);
+                       }
+                       break;
                case 's':
                        if (numtag >= sizeof(show) / sizeof(*show)) {
                                fprintf(stderr, "Too many tags specified\n");
@@ -158,7 +182,7 @@ int main(int argc, char **argv)
 
                if ((dev = blkid_find_dev_with_tag(cache, search_type,
                                                   search_value))) {
-                       print_tags(dev, show, numtag);
+                       print_tags(dev, show, numtag, output_format);
                        err = 0;
                }
        /* If we didn't specify a single device, show all available devices */
@@ -170,7 +194,7 @@ int main(int argc, char **argv)
 
                iter = blkid_dev_iterate_begin(cache);
                while (blkid_dev_next(iter, &dev) == 0) {
-                       print_tags(dev, show, numtag);
+                       print_tags(dev, show, numtag, output_format);
                        err = 0;
                }
                blkid_dev_iterate_end(iter);
@@ -180,7 +204,7 @@ int main(int argc, char **argv)
                                                  BLKID_DEV_NORMAL);
 
                if (dev) {
-                       print_tags(dev, show, numtag);
+                       print_tags(dev, show, numtag, output_format);
                        err = 0;
                }
        }