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e2fsprogs
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Code Issues Releases Wiki Activity

Add support for XFS filesystems.

bitmap-optimize
Theodore Ts'o 2001-07-03 21:43:07 -04:00
parent 342d847db3
commit 21d14ec7aa
1 changed files with 33 additions and 12 deletions
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45
misc/get_device_by_label.c
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@ -48,6 +48,15 @@ struct ext2_super_block {
}; };
#define ext2magic(s) ((unsigned int) s.s_magic[0] + (((unsigned int) s.s_magic[1]) << 8)) #define ext2magic(s) ((unsigned int) s.s_magic[0] + (((unsigned int) s.s_magic[1]) << 8))
#define XFS_SUPER_MAGIC "XFSB"
struct xfs_super_block {
unsigned char s_magic[4];
unsigned char s_dummy[28];
unsigned char s_uuid[16];
unsigned char s_dummy2[60];
unsigned char s_fname[12];
};
static struct uuidCache_s { static struct uuidCache_s {
struct uuidCache_s *next; struct uuidCache_s *next;
char uuid[16]; char uuid[16];
@ -55,34 +64,46 @@ static struct uuidCache_s {
char *device; char *device;
} *uuidCache = NULL; } *uuidCache = NULL;
/* for now, only ext2 is supported */ /* for now, only ext2 and xfs are supported */
static int static int
get_label_uuid(const char *device, char **label, char *uuid) { get_label_uuid(const char *device, char **label, char *uuid) {
/* start with a test for ext2, taken from mount_guess_fstype */ /* start with ext2 and xfs tests, taken from mount_guess_fstype */
/* should merge these later */ /* should merge these later */
int fd; int fd;
size_t label_size;
char *sb_uuid = 0, *sb_label = 0;
struct ext2_super_block e2sb; struct ext2_super_block e2sb;
struct xfs_super_block xfsb;
fd = open(device, O_RDONLY); fd = open(device, O_RDONLY);
if (fd < 0) if (fd < 0)
return 1; return 1;
if (lseek(fd, 1024, SEEK_SET) != 1024 if (lseek(fd, 1024, SEEK_SET) == 1024
|| read(fd, (char *) &e2sb, sizeof(e2sb)) != sizeof(e2sb) && read(fd, (char *) &e2sb, sizeof(e2sb)) == sizeof(e2sb)
|| (ext2magic(e2sb) != EXT2_SUPER_MAGIC)) { && (ext2magic(e2sb) == EXT2_SUPER_MAGIC)) {
sb_uuid = e2sb.s_uuid;
sb_label = e2sb.s_volume_name;
label_size = sizeof(e2sb.s_volume_name);
} else if (lseek(fd, 0, SEEK_SET) == 0
&& read(fd, (char *) &xfsb, sizeof(xfsb)) == sizeof(xfsb)
&& strncmp((char *) &xfsb.s_magic, XFS_SUPER_MAGIC, 4) == 0) {
sb_uuid = xfsb.s_uuid;
sb_label = xfsb.s_fname;
label_size = sizeof(xfsb.s_fname);
} else {
close(fd); close(fd);
return 1; return 1;
} }
close(fd); close(fd);
if (sb_uuid)
/* superblock is ext2 - now what is its label? */ memcpy(uuid, sb_uuid, sizeof(e2sb.s_uuid));
memcpy(uuid, e2sb.s_uuid, sizeof(e2sb.s_uuid)); if (sb_label) {
if ((*label = calloc(label_size + 1, 1)) != NULL)
*label = calloc(sizeof(e2sb.s_volume_name) + 1, 1); memcpy(*label, sb_label, label_size);
memcpy(*label, e2sb.s_volume_name, sizeof(e2sb.s_volume_name)); }
return 0; return 0;
} }