vol_id: add size= option

[elogind.git] / extras / volume_id / vol_id.c

diff --git a/extras/volume_id/vol_id.c b/extras/volume_id/vol_id.c
index 0137b84fbeac91e8a51878b057c8e4bafe82bb42..19aa0bd3c25d1e0de47735f1894cbd956225721b 100644 (file)
--- a/extras/volume_id/vol_id.c
+++ b/extras/volume_id/vol_id.c
@@ -117,6 +117,7 @@ int main(int argc, char *argv[])
                { "type", no_argument, NULL, 't' },
                { "export", no_argument, NULL, 'x' },
                { "skip-raid", no_argument, NULL, 's' },
+               { "size", required_argument, NULL, 'S' },
                { "probe-all", no_argument, NULL, 'a' },
                { "offset", optional_argument, NULL, 'o' },
                { "debug", no_argument, NULL, 'd' },
@@ -136,7 +137,7 @@ int main(int argc, char *argv[])
        char label_safe[256];
        char label_enc[256];
        char uuid_enc[256];
-       uint64_t size;
+       uint64_t size = 0;
        int skip_raid = 0;
        int probe_all = 0;
        uint64_t offset = 0;
@@ -158,7 +159,7 @@ int main(int argc, char *argv[])
        while (1) {
                int option;
 
-               option = getopt_long(argc, argv, "lLutxsaodh", options, NULL);
+               option = getopt_long(argc, argv, "lLutxsS:aodh", options, NULL);
                if (option == -1)
                        break;
 
@@ -189,6 +190,10 @@ int main(int argc, char *argv[])
                case 'a':
                        probe_all = 1;
                        break;
+               case 'S':
+                       if (optarg[0] != '\0')
+                               size = strtoull(optarg, NULL, 0);
+                       break;
                case 'o':
                        if (optarg[0] != '\0')
                                offset = strtoull(optarg, NULL, 0);
@@ -203,6 +208,7 @@ int main(int argc, char *argv[])
                            " --skip-raid      don't probe for raid\n"
                            " --probe-all      find possibly conflicting signatures\n"
                            " --offset=<bytes> probe at the given offset\n"
+                           " --size=<bytes>   overwrite device size\n"
                            " --debug          print debug output to stderr\n"
                            " --help\n\n");
                        goto exit;
@@ -233,9 +239,11 @@ int main(int argc, char *argv[])
                goto exit;
        }
 
-       if (ioctl(fd, BLKGETSIZE64, &size) != 0)
-               size = 0;
-       info(udev_ctx, "BLKGETSIZE64=%llu (%lluGB)\n", (unsigned long long)size, (unsigned long long)size >> 30);
+       if (size == 0) {
+               if (ioctl(fd, BLKGETSIZE64, &size) != 0)
+                       size = 0;
+               info(udev_ctx, "BLKGETSIZE64=%llu (%lluGB)\n", (unsigned long long)size, (unsigned long long)size >> 30);
+       }
 
        /* try to drop all privileges before reading disk content */
        if (getuid() == 0) {