part_efi: move uuid<->string conversion functions into lib/uuid.c

[karo-tx-uboot.git] / lib / uuid.c

diff --git a/lib/uuid.c b/lib/uuid.c
index c48bf3836262d507581c028f9538a5e0ae93c222..3af3a7dfaeca51bc469e6badd3857fdb26b8ce00 100644 (file)
--- a/lib/uuid.c
+++ b/lib/uuid.c
@@ -5,18 +5,40 @@
  */
 
 #include <linux/ctype.h>
-#include "common.h"
+#include <errno.h>
+#include <common.h>
+
+#define UUID_STR_LEN           36
 
 /*
- * This is what a UUID string looks like.
+ * UUID - Universally Unique IDentifier - 128 bits unique number.
+ *        There are 5 versions and one variant of UUID defined by RFC4122
+ *        specification. Depends on version uuid number base on a time,
+ *        host name, MAC address or random data.
+ *
+ * UUID binary format (16 bytes):
+ *
+ * 4B-2B-2B-2B-6B (big endian - network byte order)
+ *
+ * UUID string is 36 length of characters (36 bytes):
+ *
+ * 0        9    14   19   24
+ * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+ *    be     be   be   be       be
+ *
+ * where x is a hexadecimal character. Fields are separated by '-'s.
+ * When converting to a binary UUID, le means the field should be converted
+ * to little endian and be means it should be converted to big endian.
  *
- * x is a hexadecimal character. fields are separated by '-'s. When converting
- * to a binary UUID, le means the field should be converted to little endian,
- * and be means it should be converted to big endian.
+ * UUID is also used as GUID (Globally Unique Identifier) with the same binary
+ * format but it differs in string format like below.
  *
+ * GUID:
  * 0        9    14   19   24
  * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
  *    le     le   le   be       be
+ *
+ * GUID is used e.g. in GPT (GUID Partition Table) as a partiions unique id.
  */
 
 int uuid_str_valid(const char *uuid)
@@ -43,14 +65,17 @@ int uuid_str_valid(const char *uuid)
        return 1;
 }
 
-void uuid_str_to_bin(const char *uuid, unsigned char *out)
+int uuid_str_to_bin(char *uuid, unsigned char *out)
 {
        uint16_t tmp16;
        uint32_t tmp32;
        uint64_t tmp64;
 
        if (!uuid || !out)
-               return;
+               return -EINVAL;
+
+       if (strlen(uuid) != UUID_STR_LEN)
+               return -EINVAL;
 
        tmp32 = cpu_to_le32(simple_strtoul(uuid, NULL, 16));
        memcpy(out, &tmp32, 4);
@@ -66,4 +91,26 @@ void uuid_str_to_bin(const char *uuid, unsigned char *out)
 
        tmp64 = cpu_to_be64(simple_strtoull(uuid + 24, NULL, 16));
        memcpy(out + 10, (char *)&tmp64 + 2, 6);
+
+       return 0;
+}
+
+void uuid_bin_to_str(unsigned char *uuid, char *str)
+{
+       static const u8 le[16] = {3, 2, 1, 0, 5, 4, 7, 6, 8, 9, 10, 11,
+                                 12, 13, 14, 15};
+       int i;
+
+       for (i = 0; i < 16; i++) {
+               sprintf(str, "%02x", uuid[le[i]]);
+               str += 2;
+               switch (i) {
+               case 3:
+               case 5:
+               case 7:
+               case 9:
+                       *str++ = '-';
+                       break;
+               }
+       }
 }