fs/fat: implement fsuuid command
The FAT file system does not have a UUID but a 4 byte volume ID.
Let the fsuuid command show it in XXXX-XXXX format.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index c9742d5..157dad6 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -1377,3 +1377,21 @@
void fat_close(void)
{
}
+
+int fat_uuid(char *uuid_str)
+{
+ boot_sector bs;
+ volume_info volinfo;
+ int fatsize;
+ int ret;
+ u8 *id;
+
+ ret = read_bootsectandvi(&bs, &volinfo, &fatsize);
+ if (ret)
+ return ret;
+
+ id = volinfo.volume_id;
+ sprintf(uuid_str, "%02X%02X-%02X%02X", id[3], id[2], id[1], id[0]);
+
+ return 0;
+}
diff --git a/fs/fs.c b/fs/fs.c
index 7a40206..5e80648 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -194,7 +194,7 @@
.unlink = fs_unlink_unsupported,
.mkdir = fs_mkdir_unsupported,
#endif
- .uuid = fs_uuid_unsupported,
+ .uuid = fat_uuid,
.opendir = fat_opendir,
.readdir = fat_readdir,
.closedir = fat_closedir,
diff --git a/include/fat.h b/include/fat.h
index 8cae283..b9f273f 100644
--- a/include/fat.h
+++ b/include/fat.h
@@ -212,4 +212,16 @@
int fat_mkdir(const char *dirname);
void fat_close(void);
void *fat_next_cluster(fat_itr *itr, unsigned int *nbytes);
+
+/**
+ * fat_uuid() - get FAT volume ID
+ *
+ * The FAT volume ID returned in @uuid_str as hexadecimal number in XXXX-XXXX
+ * format.
+ *
+ * @uuid_str: caller allocated buffer of at least 10 bytes for the volume ID
+ * Return: 0 on success
+ */
+int fat_uuid(char *uuid_str);
+
#endif /* _FAT_H_ */