move generate_uuid from mkswap to libbb

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

3 files changed, 79 insertions, 79 deletions

diff --git a/include/libbb.h b/include/libbb.h
index be175d79f..6e629d187 100644
--- 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 aa0812914..e47b01dc1 100644
--- 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 f71884340..226831bba 100644
--- 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.