id generator support variable sn bits

HISTORY

@@ -1,5 +1,5 @@
 
-Version 1.27  2016-04-10
+Version 1.27  2016-04-15
   * add function fd_set_cloexec
   * php-fastcommon.spec.in support PHP 7
   * add file lock and unlock functions

php-fastcommon/fastcommon.c

@@ -368,7 +368,7 @@ ZEND_FUNCTION(fastcommon_is_private_ip)
 
 /*
 bool fastcommon_id_generator_init([string filename = "/tmp/fastcommon_id_generator.sn",
-	int machine_id = 0, int mid_bits = 16])
+	int machine_id = 0, int mid_bits = 16, int sn_bits = 16])
 return true for success, false for fail
 */
 ZEND_FUNCTION(fastcommon_id_generator_init)
@@ -377,10 +377,11 @@ ZEND_FUNCTION(fastcommon_id_generator_init)
     zend_size_t filename_len;
     long machine_id;
     long mid_bits;
+    long sn_bits;
     char *filename;
 
 	argc = ZEND_NUM_ARGS();
-	if (argc > 3) {
+	if (argc > 4) {
 		logError("file: "__FILE__", line: %d, "
 			"fastcommon_id_generator_init parameters count: %d is invalid",
 			__LINE__, argc);
@@ -388,10 +389,12 @@ ZEND_FUNCTION(fastcommon_id_generator_init)
 	}
 
 	filename = DEFAULT_SN_FILENAME;
+    filename_len = 0;
 	machine_id = 0;
 	mid_bits = 16;
-	if (zend_parse_parameters(argc TSRMLS_CC, "|sll", &filename,
+    sn_bits = 16;
-                &filename_len, &machine_id, &mid_bits) == FAILURE)
+	if (zend_parse_parameters(argc TSRMLS_CC, "|slll", &filename,
+                &filename_len, &machine_id, &mid_bits, &sn_bits) == FAILURE)
 	{
 		logError("file: "__FILE__", line: %d, "
 			"zend_parse_parameters fail!", __LINE__);
@@ -399,13 +402,13 @@ ZEND_FUNCTION(fastcommon_id_generator_init)
 	}
 
 	if (idg_context.fd >= 0) {
-		logError("file: "__FILE__", line: %d, "
+		logWarning("file: "__FILE__", line: %d, "
 			"already inited!", __LINE__);
 		RETURN_BOOL(false);
 	}
 
 	if (id_generator_init_ex(&idg_context, filename,
-			machine_id, mid_bits) != 0)
+			machine_id, mid_bits, sn_bits) != 0)
 	{
 		RETURN_BOOL(false);
 	}

php-fastcommon/test.php

@@ -16,11 +16,13 @@ while (($next_ip=fastcommon_get_next_local_ip($next_ip)))
     echo "local ip: $next_ip, private: $is_private_ip\n";
 }
 
-fastcommon_id_generator_init("/tmp/sn.txt");
+fastcommon_id_generator_init();
+//fastcommon_id_generator_init("/tmp/sn.txt", 0, 8, 16);
 
 var_dump(fastcommon_id_generator_next());
 for ($i=0; $i<10; $i++) {
-	echo fastcommon_id_generator_next() . "\n";
+	$id = fastcommon_id_generator_next();
+    printf("%d %X\n", $id, $id);
 }
 
 fastcommon_id_generator_destroy();

src/id_generator.c

@@ -22,7 +22,7 @@
 #include "id_generator.h"
 
 int id_generator_init_ex(struct idg_context *context, const char *filename,
-    const int machine_id, const int mid_bits)
+    const int machine_id, const int mid_bits, const int sn_bits)
 {
 	int result;
 	int mid;
@@ -34,6 +34,23 @@ int id_generator_init_ex(struct idg_context *context, const char *filename,
 		context->fd = -1;
 		return EINVAL;
 	}
+	if (sn_bits < 8)
+	{
+		logError("file: "__FILE__", line: %d, "
+			"invalid bits of serial no: %d < 8",
+			__LINE__, sn_bits);
+		context->fd = -1;
+		return EINVAL;
+	}
+	if (mid_bits + sn_bits > 32)
+	{
+		logError("file: "__FILE__", line: %d, "
+			"invalid mid_bits + sn_bits: %d > 32",
+			__LINE__, mid_bits + sn_bits);
+		context->fd = -1;
+		return EINVAL;
+	}
+
 	if (machine_id < 0 || machine_id >= (1 << mid_bits))
 	{
 		logError("file: "__FILE__", line: %d, "
@@ -102,7 +119,8 @@ int id_generator_init_ex(struct idg_context *context, const char *filename,
 
 	context->machine_id = mid;
 	context->mid_bits = mid_bits;
-	context->sn_bits = 32 - mid_bits;
+	context->sn_bits = sn_bits;
+	context->mid_sn_bits = mid_bits + sn_bits;
 	context->masked_mid = ((int64_t)mid) << context->sn_bits;
 	context->sn_mask = ((int64_t)1 << context->sn_bits) - 1;
 
@@ -132,6 +150,7 @@ int id_generator_next(struct idg_context *context, int64_t *id)
 
 	if ((result=file_write_lock(context->fd)) != 0)
 	{
+        *id = 0;
 		return result;
 	}
 
@@ -187,7 +206,8 @@ int id_generator_next(struct idg_context *context, int64_t *id)
 
 	file_unlock(context->fd);
 
-	*id = (((int64_t)time(NULL)) << 32) | context->masked_mid | (sn & context->sn_mask);
+	*id = (((int64_t)time(NULL)) << context->mid_sn_bits) |
+        context->masked_mid | (sn & context->sn_mask);
 	return result;
 }
 

src/id_generator.h

@@ -32,6 +32,7 @@ struct idg_context {
     int machine_id;
     int mid_bits;   //bits of machine id
     int sn_bits;    //bits of serial number
+    int mid_sn_bits;  //mid_bits + sn_bits
     int64_t masked_mid;
     int64_t sn_mask;
 };
@@ -42,16 +43,18 @@ struct idg_context {
 *   context: the id generator context
 *   filename: the filename to store id
 *   machine_id: the machine id, 0 for auto generate by local ip address
-*   mid_bits:  the bits of the machine id, such as 16
+*   mid_bits:  the bits of machine id, such as 16
+*   sn_bits:  the bits of serial no, such as 16, mid_bits + sn_bits must <= 32
 * return error no, 0 for success, none zero for fail
 */
 int id_generator_init_ex(struct idg_context *context, const char *filename,
-    const int machine_id, const int mid_bits);
+    const int machine_id, const int mid_bits, const int sn_bits);
 
 /**
 * init function
-    set mid_bits to 16
     set machine_id to 2 bytes of local ip address
+    set mid_bits to 16
+    set sn_bits to 16
 * parameter:
 *   context: the id generator context
 *   filename: the filename to store id
@@ -61,7 +64,8 @@ static inline int id_generator_init(struct idg_context *context, const char *fil
 {
 	const int machine_id = 0;
 	const int mid_bits = 16;
-	return id_generator_init_ex(context, filename, machine_id, mid_bits);
+	const int sn_bits = 16;
+	return id_generator_init_ex(context, filename, machine_id, mid_bits, sn_bits);
 }
 
 /**

src/tests/test_id_generator.c

@@ -22,13 +22,14 @@ int main(int argc, char *argv[])
 	int64_t id;
 	const int machine_id = 0;
 	const int mid_bits = 12;
+	const int sn_bits = 16;
 	
 	log_init();
 	g_log_context.log_level = LOG_DEBUG;
 
 	//result = id_generator_init(&context, "/tmp/sn.txt");
 	result = id_generator_init_ex(&context, "/tmp/sn.txt",
-		machine_id, mid_bits);
+		machine_id, mid_bits, sn_bits);
 	if (result != 0)
 	{
 		return result;