move generate_uuid from mkswap to libbb

Signed-off-by: Vladimir Dronnikov <dronnikov@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/include/libbb.h b/include/libbb.h
index be175d79f9af55be4d9b4f6ea1e09f81a6af0f54..6e629d187e2e4d653b4eb47fbca18d8135b72794 100644 (file)
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -701,6 +701,9 @@ const char *make_human_readable_str(unsigned long long size,
 /* Put a string of hex bytes ("1b2e66fe"...), return advanced pointer */
 char *bin2hex(char *buf, const char *cp, int count) FAST_FUNC;
 
+/* Generate a UUID */
+void generate_uuid(uint8_t *buf) FAST_FUNC;
+
 /* Last element is marked by mult == 0 */
 struct suffix_mult {
        char suffix[4];

diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index aa0812914a04b09bd14e56cbb21d0ab7a5de36a3..e47b01dc1dc5e8c7f3ee9d7bc1d731c533f95f10 100644 (file)
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -209,3 +209,66 @@ int FAST_FUNC tcsetattr_stdin_TCSANOW(const struct termios *tp)
 {
        return tcsetattr(STDIN_FILENO, TCSANOW, tp);
 }
+
+void FAST_FUNC generate_uuid(uint8_t *buf)
+{
+       /* http://www.ietf.org/rfc/rfc4122.txt
+        *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+        * |                          time_low                             |
+        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+        * |       time_mid                |         time_hi_and_version   |
+        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+        * |clk_seq_and_variant            |         node (0-1)            |
+        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+        * |                         node (2-5)                            |
+        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+        * IOW, uuid has this layout:
+        * uint32_t time_low (big endian)
+        * uint16_t time_mid (big endian)
+        * uint16_t time_hi_and_version (big endian)
+        *  version is a 4-bit field:
+        *   1 Time-based
+        *   2 DCE Security, with embedded POSIX UIDs
+        *   3 Name-based (MD5)
+        *   4 Randomly generated
+        *   5 Name-based (SHA-1)
+        * uint16_t clk_seq_and_variant (big endian)
+        *  variant is a 3-bit field:
+        *   0xx Reserved, NCS backward compatibility
+        *   10x The variant specified in rfc4122
+        *   110 Reserved, Microsoft backward compatibility
+        *   111 Reserved for future definition
+        * uint8_t node[6]
+        *
+        * For version 4, these bits are set/cleared:
+        * time_hi_and_version & 0x0fff | 0x4000
+        * clk_seq_and_variant & 0x3fff | 0x8000
+        */
+       pid_t pid;
+       int i;
+
+       i = open("/dev/urandom", O_RDONLY);
+       if (i >= 0) {
+               read(i, buf, 16);
+               close(i);
+       }
+       /* Paranoia. /dev/urandom may be missing.
+        * rand() is guaranteed to generate at least [0, 2^15) range,
+        * but lowest bits in some libc are not so "random".  */
+       srand(monotonic_us());
+       pid = getpid();
+       while (1) {
+               for (i = 0; i < 16; i++)
+                       buf[i] ^= rand() >> 5;
+               if (pid == 0)
+                       break;
+               srand(pid);
+               pid = 0;
+       }
+
+       /* version = 4 */
+       buf[4 + 2    ] = (buf[4 + 2    ] & 0x0f) | 0x40;
+       /* variant = 10x */
+       buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
+}

diff --git a/util-linux/mkswap.c b/util-linux/mkswap.c
index f71884340e7d318aa3acb0e7d5db103764d81bb5..226831bba4f3cbd6a44aa0f9dae904ae8d3bdd88 100644 (file)
--- a/util-linux/mkswap.c
+++ b/util-linux/mkswap.c
@@ -50,84 +50,6 @@ static void mkswap_selinux_setcontext(int fd, const char *path)
 # define mkswap_selinux_setcontext(fd, path) ((void)0)
 #endif
 
-#if ENABLE_FEATURE_MKSWAP_UUID
-static void mkswap_generate_uuid(uint8_t *buf)
-{
-       /* http://www.ietf.org/rfc/rfc4122.txt
-        *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-        * |                          time_low                             |
-        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-        * |       time_mid                |         time_hi_and_version   |
-        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-        * |clk_seq_and_variant            |         node (0-1)            |
-        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-        * |                         node (2-5)                            |
-        * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-        * IOW, uuid has this layout:
-        * uint32_t time_low (big endian)
-        * uint16_t time_mid (big endian)
-        * uint16_t time_hi_and_version (big endian)
-        *  version is a 4-bit field:
-        *   1 Time-based
-        *   2 DCE Security, with embedded POSIX UIDs
-        *   3 Name-based (MD5)
-        *   4 Randomly generated
-        *   5 Name-based (SHA-1)
-        * uint16_t clk_seq_and_variant (big endian)
-        *  variant is a 3-bit field:
-        *   0xx Reserved, NCS backward compatibility
-        *   10x The variant specified in rfc4122
-        *   110 Reserved, Microsoft backward compatibility
-        *   111 Reserved for future definition
-        * uint8_t node[6]
-        *
-        * For version 4, these bits are set/cleared:
-        * time_hi_and_version & 0x0fff | 0x4000
-        * clk_seq_and_variant & 0x3fff | 0x8000
-        */
-       pid_t pid;
-       int i;
-       char uuid_string[32];
-
-       i = open("/dev/urandom", O_RDONLY);
-       if (i >= 0) {
-               read(i, buf, 16);
-               close(i);
-       }
-       /* Paranoia. /dev/urandom may be missing.
-        * rand() is guaranteed to generate at least [0, 2^15) range,
-        * but lowest bits in some libc are not so "random".  */
-       srand(monotonic_us());
-       pid = getpid();
-       while (1) {
-               for (i = 0; i < 16; i++)
-                       buf[i] ^= rand() >> 5;
-               if (pid == 0)
-                       break;
-               srand(pid);
-               pid = 0;
-       }
-
-       /* version = 4 */
-       buf[4 + 2    ] = (buf[4 + 2    ] & 0x0f) | 0x40;
-       /* variant = 10x */
-       buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
-
-       bin2hex(uuid_string, (void*) buf, 16);
-       /* f.e. UUID=dfd9c173-be52-4d27-99a5-c34c6c2ff55f */
-       printf("UUID=%.8s"  "-%.4s-%.4s-%.4s-%.12s\n",
-               uuid_string,
-               uuid_string+8,
-               uuid_string+8+4,
-               uuid_string+8+4+4,
-               uuid_string+8+4+4+4
-       );
-}
-#else
-# define mkswap_generate_uuid(buf) ((void)0)
-#endif
-
 #if 0 /* from Linux 2.6.23 */
 /*
  * Magic header for a swap area. The first part of the union is
@@ -190,7 +112,19 @@ int mkswap_main(int argc, char **argv)
        // Make a header. hdr is zero-filled so far...
        hdr[0] = 1;
        hdr[1] = (len / pagesize) - 1;
-       mkswap_generate_uuid((void*) &hdr[3]);
+#if ENABLE_FEATURE_MKSWAP_UUID
+       char uuid_string[32];
+       generate_uuid((void*) &hdr[3]);
+       bin2hex(uuid_string, (void*) &hdr[3], 16);
+       /* f.e. UUID=dfd9c173-be52-4d27-99a5-c34c6c2ff55f */
+       printf("UUID=%.8s"  "-%.4s-%.4s-%.4s-%.12s\n",
+               uuid_string,
+               uuid_string+8,
+               uuid_string+8+4,
+               uuid_string+8+4+4,
+               uuid_string+8+4+4+4
+       );
+#endif
 
        // Write the header.  Sync to disk because some kernel versions check
        // signature on disk (not in cache) during swapon.