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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:49:25 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:49:25 +0000 |
commit | 464df1d5e5ab1322e2dd0a7796939fff1aeefa9a (patch) | |
tree | 6a403684e0978f0287d7f0ec0e5aab1fd31a59e1 /misc/e2label.c | |
parent | Initial commit. (diff) | |
download | e2fsprogs-464df1d5e5ab1322e2dd0a7796939fff1aeefa9a.tar.xz e2fsprogs-464df1d5e5ab1322e2dd0a7796939fff1aeefa9a.zip |
Adding upstream version 1.47.0.upstream/1.47.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'misc/e2label.c')
-rw-r--r-- | misc/e2label.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/misc/e2label.c b/misc/e2label.c new file mode 100644 index 0000000..910ccc7 --- /dev/null +++ b/misc/e2label.c @@ -0,0 +1,121 @@ +/* + * e2label.c - Print or change the volume label on an ext2 fs + * + * Written by Andries Brouwer (aeb@cwi.nl), 970714 + * + * Copyright 1997, 1998 by Theodore Ts'o. + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + */ + +#include "config.h" +#include <stdio.h> +#include <string.h> +#include <fcntl.h> +#include <ctype.h> +#include <termios.h> +#include <time.h> +#ifdef HAVE_GETOPT_H +#include <getopt.h> +#else +extern char *optarg; +extern int optind; +#endif +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#ifdef HAVE_STDLIB_H +#include <stdlib.h> +#endif +#ifdef HAVE_ERRNO_H +#include <errno.h> +#endif +#include "support/nls-enable.h" + +#define EXT2_SUPER_MAGIC 0xEF53 + +#define VOLNAMSZ 16 + +struct ext2_super_block { + char s_dummy0[56]; + unsigned char s_magic[2]; + char s_dummy1[62]; + char s_volume_name[VOLNAMSZ]; + char s_last_mounted[64]; + char s_dummy2[824]; +} sb; + +static int open_e2fs (char *dev, int mode) +{ + int fd; + + fd = open(dev, mode); + if (fd < 0) { + perror(dev); + fprintf (stderr, _("e2label: cannot open %s\n"), dev); + exit(1); + } + if (lseek(fd, 1024, SEEK_SET) != 1024) { + perror(dev); + fprintf (stderr, _("e2label: cannot seek to superblock\n")); + exit(1); + } + if (read(fd, (char *) &sb, sizeof(sb)) != sizeof(sb)) { + perror(dev); + fprintf (stderr, _("e2label: error reading superblock\n")); + exit(1); + } + if (sb.s_magic[0] + 256*sb.s_magic[1] != EXT2_SUPER_MAGIC) { + fprintf (stderr, _("e2label: not an ext2 filesystem\n")); + exit(1); + } + + return fd; +} + +static void print_label (char *dev) +{ + char label[VOLNAMSZ+1]; + + open_e2fs (dev, O_RDONLY); + snprintf(label, sizeof(label), "%.*s", EXT2_LEN_STR(sb.s_volume_name)); + label[VOLNAMSZ] = 0; + printf("%s\n", label); +} + +static void change_label (char *dev, char *label) +{ + int fd; + + fd = open_e2fs(dev, O_RDWR); + memset(sb.s_volume_name, 0, VOLNAMSZ); + strncpy(sb.s_volume_name, label, VOLNAMSZ); + if (strlen(label) > VOLNAMSZ) + fprintf(stderr, _("Warning: label too long, truncating.\n")); + if (lseek(fd, 1024, SEEK_SET) != 1024) { + perror(dev); + fprintf (stderr, _("e2label: cannot seek to superblock again\n")); + exit(1); + } + if (write(fd, (char *) &sb, sizeof(sb)) != sizeof(sb)) { + perror(dev); + fprintf (stderr, _("e2label: error writing superblock\n")); + exit(1); + } +} + +int main (int argc, char ** argv) +{ + if (argc == 2) + print_label(argv[1]); + else if (argc == 3) + change_label(argv[1], argv[2]); + else { + fprintf(stderr, _("Usage: e2label device [newlabel]\n")); + exit(1); + } + return 0; +} |