Substantial simplification of uuid_t

The string format of UUID is not used in 0MQ. Further on,
it turns out that UUIDs have fixed microarchitecture-agnostic
binary layout (see RFC4122). Thus, the conversion to string
and back to binary can be avoided.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

src/socket_base.cpp

@@ -219,8 +219,8 @@ void zmq::socket_base_t::attach_pipes (class reader_t *inpipe_,
         xattach_pipes (inpipe_, outpipe_, peer_identity_);
     }
     else {
-        blob_t identity (1, 0);
-        identity.append (uuid_t ().to_blob (), uuid_t::uuid_blob_len);
+        blob_t identity (17, 0);
+        generate_uuid ((unsigned char*) identity.data () + 1);
         xattach_pipes (inpipe_, outpipe_, identity);
     }
 }

src/uuid.cpp

@@ -18,56 +18,32 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <string.h>
+
 #include "uuid.hpp"
 #include "err.hpp"
+#include "stdint.hpp"
+#include "platform.hpp"
 
 #if defined ZMQ_HAVE_WINDOWS
 
-zmq::uuid_t::uuid_t ()
-{
-    RPC_STATUS ret = UuidCreate (&uuid);
-    zmq_assert (ret == RPC_S_OK);
-    ret = UuidToString (&uuid, &string_buf);
-    zmq_assert (ret == RPC_S_OK);
-
-    create_blob ();
-}
-
-zmq::uuid_t::~uuid_t ()
-{
-    if (string_buf)
-        RpcStringFree (&string_buf);
-}
+#include <rpc.h>
 
-const char *zmq::uuid_t::to_string ()
+void zmq::generate_uuid (void *buf_)
 {
-    return (char*) string_buf;
+    RPC_STATUS ret = UuidCreate ((::UUID*) buf_);
+    zmq_assert (ret == RPC_S_OK);
 }
 
 #elif defined ZMQ_HAVE_FREEBSD || defined ZMQ_HAVE_NETBSD
 
-#include <stdlib.h>
 #include <uuid.h>
 
-zmq::uuid_t::uuid_t ()
+void zmq::generate_uuid (void *buf_)
 {
     uint32_t status;
-    uuid_create (&uuid, &status);
+    uuid_create ((::uuid_t*) buf_, &status);
     zmq_assert (status == uuid_s_ok);
-    uuid_to_string (&uuid, &string_buf, &status);
-    zmq_assert (status == uuid_s_ok);
-
-    create_blob ();
-}
-
-zmq::uuid_t::~uuid_t ()
-{
-    free (string_buf);
-}
-
-const char *zmq::uuid_t::to_string ()
-{
-    return string_buf;
 }
 
 #elif defined ZMQ_HAVE_LINUX || defined ZMQ_HAVE_SOLARIS ||\
@@ -75,159 +51,40 @@ const char *zmq::uuid_t::to_string ()
 
 #include <uuid/uuid.h>
 
-zmq::uuid_t::uuid_t ()
+void zmq::generate_uuid (void *buf_)
 {
-    uuid_generate (uuid);
-    uuid_unparse (uuid, string_buf);
-
-    create_blob ();
-}
-
-zmq::uuid_t::~uuid_t ()
-{
-}
-
-const char *zmq::uuid_t::to_string ()
-{
-    return string_buf;
+    uuid_generate ((unsigned char*) buf_);
 }
 
 #elif defined ZMQ_HAVE_OPENVMS
 
 #include <starlet.h>
 
-#define uuid_generate(x) sys$create_uid(&(x))
-
-#define uuid_unparse(x, y) \
-        sprintf (y, "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x", \
-                        x.data0, x.data1, x.data2, \
-                        x.data3 [0], x.data3 [1], \
-                        x.data3 [2], x.data3 [3], \
-                        x.data3 [4], x.data3 [5], \
-                        x.data3 [6], x.data3 [7]);
-
-zmq::uuid_t::uuid_t ()
-{
-    uuid_generate (uuid);
-    uuid_unparse (uuid, string_buf);
-}
-
-zmq::uuid_t::~uuid_t ()
-{
-}
-
-const char *zmq::uuid_t::to_string ()
+void zmq::generate_uuid (void *buf_)
 {
-    return string_buf;
+    sys$create_uid(buf_);
 }
 
 #else
 
-#include <stdio.h>
-#include <string.h>
 #include <openssl/rand.h>
 
-zmq::uuid_t::uuid_t ()
+void zmq::generate_uuid (void *buf_)
 {
-    unsigned char rand_buf [16];
-    int ret = RAND_bytes (rand_buf, sizeof rand_buf);
+    unsigned char *buf = (unsigned char*) buf_;
+
+    //  Generate random value.
+    int ret = RAND_bytes (buf, 16);
     zmq_assert (ret == 1);
 
-    //  Read in UUID fields.
-    memcpy (&time_low, rand_buf, sizeof time_low);
-    memcpy (&time_mid, rand_buf + 4, sizeof time_mid);
-    memcpy (&time_hi_and_version, rand_buf + 6, sizeof time_hi_and_version);
-    memcpy (&clock_seq_hi_and_reserved, rand_buf + 8,
-        sizeof clock_seq_hi_and_reserved);
-    memcpy (&clock_seq_low, rand_buf + 9, sizeof clock_seq_low);
-    memcpy (&node [0], rand_buf + 10, sizeof node);
-
-    //  Store UUID version number.
-    time_hi_and_version = (time_hi_and_version & 0x0fff) | 4 << 12;
-
-    //  Store UUID type.
-    clock_seq_hi_and_reserved = (clock_seq_hi_and_reserved & 0x3f) | 0x80;
-
-    snprintf (string_buf, sizeof string_buf,
-        "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
-        time_low,
-        time_mid,
-        time_hi_and_version,
-        clock_seq_hi_and_reserved,
-        clock_seq_low,
-        node [0], node [1], node [2], node [3], node [4], node [5]);
-
-    create_blob ();
-}
+    //  Set UUID variant to 2 (UUID as specified in RFC4122).
+    const unsigned char variant = 2;
+    buf [8] = (buf [8] & 0x3f) | (variant << 6);
 
-zmq::uuid_t::~uuid_t ()
-{
-}
-
-const char *zmq::uuid_t::to_string ()
-{
-    return string_buf;
+    //  Set UUID version to 4 (randomly or pseudo-randomly generated UUID).
+    const unsigned char version = 4;
+    buf [6] = (buf [6] & 0x0f) | (version << 4);
 }
 
 #endif
 
-const unsigned char *zmq::uuid_t::to_blob ()
-{
-    return blob_buf;
-}
-
-unsigned char zmq::uuid_t::convert_byte (const char *hexa_)
-{
-    unsigned char byte;
-
-    if (*hexa_ >= '0' && *hexa_ <= '9')
-        byte = *hexa_ - '0';
-    else if (*hexa_ >= 'A' && *hexa_ <= 'F')
-        byte = *hexa_ - 'A' + 10;
-    else if (*hexa_ >= 'a' && *hexa_ <= 'f')
-        byte = *hexa_ - 'a' + 10;
-    else {
-        zmq_assert (false);
-        byte = 0;
-    }
-
-    byte *= 16;
-
-    hexa_++;
-    if (*hexa_ >= '0' && *hexa_ <= '9')
-        byte += *hexa_ - '0';
-    else if (*hexa_ >= 'A' && *hexa_ <= 'F')
-        byte += *hexa_ - 'A' + 10;
-    else if (*hexa_ >= 'a' && *hexa_ <= 'f')
-        byte += *hexa_ - 'a' + 10;
-    else
-        zmq_assert (false);  
-
-    return byte;
-}
-
-void zmq::uuid_t::create_blob ()
-{
-    const char *buf = (const char*) string_buf;
-
-    blob_buf [0] = convert_byte (buf + 0);
-    blob_buf [1] = convert_byte (buf + 2);
-    blob_buf [2] = convert_byte (buf + 4);
-    blob_buf [3] = convert_byte (buf + 6);
-
-    blob_buf [4] = convert_byte (buf + 9);
-    blob_buf [5] = convert_byte (buf + 11);
-
-    blob_buf [6] = convert_byte (buf + 14);
-    blob_buf [7] = convert_byte (buf + 16);
-
-    blob_buf [8] = convert_byte (buf + 19);
-    blob_buf [9] = convert_byte (buf + 21);
-
-    blob_buf [10] = convert_byte (buf + 24);
-    blob_buf [11] = convert_byte (buf + 26);
-    blob_buf [12] = convert_byte (buf + 28);
-    blob_buf [13] = convert_byte (buf + 30);
-    blob_buf [14] = convert_byte (buf + 32);
-    blob_buf [15] = convert_byte (buf + 34);
-}

src/uuid.hpp

@@ -21,90 +21,12 @@
 #ifndef __ZMQ_UUID_HPP_INCLUDED__
 #define __ZMQ_UUID_HPP_INCLUDED__
 
-#include "platform.hpp"
-#include "stdint.hpp"
-
-#if defined ZMQ_HAVE_FREEBSD || defined ZMQ_HAVE_NETBSD
-#include <uuid.h>
-#elif defined ZMQ_HAVE_LINUX || defined ZMQ_HAVE_SOLARIS ||\
-      defined ZMQ_HAVE_OSX || defined ZMQ_HAVE_CYGWIN
-#include <uuid/uuid.h>
-#elif defined ZMQ_HAVE_WINDOWS
-#include "windows.hpp"
-#include <rpc.h>
-#elif defined ZMQ_HAVE_OPENVMS
-typedef struct
-{
-    unsigned long data0;
-    unsigned short data1;
-    unsigned short data2;
-    unsigned char data3 [8];
-} uuid_t;
-#endif
-
 namespace zmq
 {
 
-    //  This class provides RFC 4122 (a Universally Unique IDentifier)
-    //  implementation.
-
-    class uuid_t
-    {
-    public:
-
-        uuid_t ();
-        ~uuid_t ();
-
-        //  The length of textual representation of UUID.
-        enum { uuid_string_len = 36 };
-
-        //  Returns a pointer to buffer containing the textual
-        //  representation of the UUID. The callee is reponsible to
-        //  free the allocated memory.
-        const char *to_string ();
-
-        //  The length of binary representation of UUID.
-        enum { uuid_blob_len = 16 };
-
-        const unsigned char *to_blob ();
-
-    private:
-
-        //  Converts one byte from hexa representation to binary.
-        unsigned char convert_byte (const char *hexa_);
-
-        //  Converts string representation of UUID into standardised BLOB.
-        //  The function is endianness agnostic.
-        void create_blob ();
-
-#if defined ZMQ_HAVE_WINDOWS
-#ifdef ZMQ_HAVE_MINGW32
-        typedef unsigned char* RPC_CSTR;
-#endif
-        ::UUID uuid;
-        RPC_CSTR string_buf;
-#elif defined ZMQ_HAVE_FREEBSD || defined ZMQ_HAVE_NETBSD
-        ::uuid_t uuid;
-        char *string_buf;
-#elif defined ZMQ_HAVE_LINUX || defined ZMQ_HAVE_SOLARIS ||\
-      defined ZMQ_HAVE_OSX || defined ZMQ_HAVE_CYGWIN ||\
-      defined ZMQ_HAVE_OPENVMS
-        ::uuid_t uuid;
-        char string_buf [uuid_string_len + 1];
-#else
-        //  RFC 4122 UUID's fields
-        uint32_t time_low;
-        uint16_t time_mid;
-        uint16_t time_hi_and_version;
-        uint8_t clock_seq_hi_and_reserved;
-        uint8_t clock_seq_low;
-        uint8_t node [6];
-
-        char string_buf [uuid_string_len + 1];
-#endif
-
-        unsigned char blob_buf [uuid_blob_len];
-    };
+    //  This function provides RFC 4122 (a Universally Unique IDentifier)
+    //  implementation. The resulting UUID will be 16 bytes long.
+    void generate_uuid (void *buf_);
 
 }
 

src/zmq_init.cpp

@@ -47,10 +47,9 @@ zmq::zmq_init_t::zmq_init_t (io_thread_t *io_thread_,
     alloc_assert (engine);
 
     //  Generate an unique identity.
-    unsigned char identity [uuid_t::uuid_blob_len + 1];
-    identity [0] = 0;
-    memcpy (identity + 1, uuid_t ().to_blob (), uuid_t::uuid_blob_len);
-    peer_identity.assign (identity, uuid_t::uuid_blob_len + 1);
+    peer_identity.resize (17);
+    peer_identity [0] = 0;
+    generate_uuid (&peer_identity [1]);
 
     //  Create a list of props to send.
     msg_t msg;