use some drupal functions for entropy

fulcrm_uuid.module

@@ -1,10 +1,14 @@
 <?php /* -*- php -*- */
 
 function fulcrm_uuid_stir_mt_srand() {
-    $e1 = variable_get( 'fulcrm_uuid_entropy_1', '' );
-    mt_srand( crc32( $e1 ) );
-    if ( function_exists( 'microtime' ) )
+    if ( function_exists( 'drupal_random_bytes' ) )
+        mt_srand( crc32( drupal_random_bytes( 4 ) ) );
+    else if ( function_exists( 'microtime' ) )
         mt_srand( crc32( microtime() ) );
+    else {
+        $e1 = variable_get( 'fulcrm_uuid_entropy_1', '' );
+        mt_srand( crc32( $e1 ) );
+    }
 }
 
 function fulcrm_uuid_stir_entropy() {
@@ -12,24 +16,28 @@ function fulcrm_uuid_stir_entropy() {
 
     $entropy = '';
 
-    $entropy .= mt_rand();
-    $entropy .= rand();
+    if ( function_exists( 'drupal_random_bytes' ) ) {
+        $entropy .= drupal_random_bytes( 32 );
+    } else {
+        $entropy .= mt_rand();
+        $entropy .= rand();
 
-    $entropy .= time();
-    if ( function_exists( 'microtime' ) )
-        $entropy .= microtime();
+        $entropy .= time();
+        if ( function_exists( 'microtime' ) )
+            $entropy .= microtime();
 
-    $entropy .= variable_get( 'cron_key', '' );
-    $entropy .= variable_get( 'cron_last', '' );
-    $entropy .= variable_get( 'drupal_private_key', '' );
-    $entropy .= variable_get( 'site_name', '' );
+        $entropy .= variable_get( 'cron_key', '' );
+        $entropy .= variable_get( 'cron_last', '' );
+        $entropy .= variable_get( 'drupal_private_key', '' );
+        $entropy .= variable_get( 'site_name', '' );
 
-    if ( function_exists( 'openssl_random_pseudo_bytes' ) )
-        $entropy .= openssl_random_pseudo_bytes( 32 );
+        if ( function_exists( 'openssl_random_pseudo_bytes' ) )
+            $entropy .= openssl_random_pseudo_bytes( 32 );
 
-    $handle = fopen( '/dev/urandom', 'r' );
-    $entropy .= fread( $handle, 32 );
-    fclose( $handle );
+        $handle = fopen( '/dev/urandom', 'r' );
+        $entropy .= fread( $handle, 32 );
+        fclose( $handle );
+    }
 
     $old_entropy = ( variable_get( 'fulcrm_uuid_entropy_1', '' ) .
                      variable_get( 'fulcrm_uuid_entropy_2', '' ) );
@@ -44,11 +52,20 @@ function fulcrm_uuid_cron() {
 }
 
 function fulcrm_uuid_uuid4() {
+    static $data = '';
+
+    if ( function_exists( 'drupal_random_bytes' ) )
+        $data = $data . drupal_random_bytes( 4 );
+    else
+        $data = $data . uniqid( $more_entropy = true );
+
     $data = ( variable_get( 'fulcrm_uuid_entropy_2', '' ) .
-              uniqid( $more_entropy = true ) .
+              $data .
               variable_get( 'fulcrm_uuid_entropy_2', '' ) );
-    $data = hex2bin( md5( $data ) );
-    $data[ 6 ] = chr( ord( $data[ 6 ] ) & 0x0f | 0x40 );
-    $data[ 8 ] = chr( ord( $data[ 8 ] ) & 0x3f | 0x80 );
-    return vsprintf( '%s%s-%s-%s-%s-%s%s%s', str_split( bin2hex( $data ), 4 ) );
+
+    $data = md5( $data );
+    $rdata = hex2bin( $data );
+    $rdata[ 6 ] = chr( ord( $rdata[ 6 ] ) & 0x0f | 0x40 );
+    $rdata[ 8 ] = chr( ord( $rdata[ 8 ] ) & 0x3f | 0x80 );
+    return vsprintf( '%s%s-%s-%s-%s-%s%s%s', str_split( bin2hex( $rdata ), 4 ) );
 }