add id generator for multi processes

HISTORY

@@ -3,6 +3,7 @@ Version 1.27  2016-04-09
   * add function fd_set_cloexec
   * php-fastcommon.spec.in support PHP 7
   * add file lock and unlock functions
+  * add id generator for multi processes
 
 Version 1.26  2016-03-16
   * add logger parameter: compress_log_days_before

src/Makefile.in

@@ -11,7 +11,7 @@ FAST_SHARED_OBJS = hash.lo chain.lo shared_func.lo ini_file_reader.lo \
                    fast_timer.lo process_ctrl.lo fast_mblock.lo \
                    connection_pool.lo fast_mpool.lo fast_allocator.lo  \
                    fast_buffer.lo multi_skiplist.lo flat_skiplist.lo \
-				   system_info.lo fast_blocked_queue.lo
+                   system_info.lo fast_blocked_queue.lo id_generator.lo
 
 FAST_STATIC_OBJS = hash.o chain.o shared_func.o ini_file_reader.o \
                    logger.o sockopt.o base64.o sched_thread.o \
@@ -20,7 +20,7 @@ FAST_STATIC_OBJS = hash.o chain.o shared_func.o ini_file_reader.o \
                    fast_timer.o process_ctrl.o fast_mblock.o \
                    connection_pool.o fast_mpool.o fast_allocator.o \
                    fast_buffer.o multi_skiplist.o flat_skiplist.o  \
-				   system_info.o fast_blocked_queue.o
+                   system_info.o fast_blocked_queue.o id_generator.o
 
 HEADER_FILES = common_define.h hash.h chain.h logger.h base64.h \
                shared_func.h pthread_func.h ini_file_reader.h _os_define.h \
@@ -29,8 +29,8 @@ HEADER_FILES = common_define.h hash.h chain.h logger.h base64.h \
                fast_timer.h process_ctrl.h fast_mblock.h \
                connection_pool.h fast_mpool.h fast_allocator.h \
                fast_buffer.h skiplist.h multi_skiplist.h flat_skiplist.h \
-			   skiplist_common.h system_info.h fast_blocked_queue.h \
+               skiplist_common.h system_info.h fast_blocked_queue.h \
-			   php7_ext_wrapper.h
+               php7_ext_wrapper.h id_generator.h
 
 ALL_OBJS = $(FAST_STATIC_OBJS) $(FAST_SHARED_OBJS)
 

src/id_generator.c

@@ -0,0 +1,177 @@
+/**
+* Copyright (C) 2008 Happy Fish / YuQing
+*
+* FastDFS may be copied only under the terms of the GNU General
+* Public License V3, which may be found in the FastDFS source kit.
+* Please visit the FastDFS Home Page http://www.csource.org/ for more detail.
+**/
+
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <netinet/in.h>
+#include "logger.h"
+#include "shared_func.h"
+#include "local_ip_func.h"
+#include "id_generator.h"
+
+int id_generator_init_ex(struct idg_context *context, const char *filename,
+    const int machine_id, const int mid_bits)
+{
+	int result;
+	int mid;
+	if (mid_bits < 2 || mid_bits > 20)
+	{
+		logError("file: "__FILE__", line: %d, "
+			"invalid bits of machine id: %d",
+			__LINE__, mid_bits);
+		context->fd = -1;
+		return EINVAL;
+	}
+	if (machine_id < 0 || machine_id >= (1 << mid_bits))
+	{
+		logError("file: "__FILE__", line: %d, "
+			"invalid machine id: %d",
+			__LINE__, machine_id);
+		context->fd = -1;
+		return EINVAL;
+	}
+	if (machine_id != 0)
+	{
+		mid = machine_id;
+	}
+	else
+	{
+		const char *local_ip;
+		struct in_addr ip_addr;
+
+		local_ip = get_first_local_ip();
+		if (local_ip == NULL)
+		{
+			logError("file: "__FILE__", line: %d, "
+				"can't get local ip address", __LINE__);
+			context->fd = -1;
+			return ENOENT;
+		}
+
+		if (inet_pton(AF_INET, local_ip, &ip_addr) != 1)
+		{
+			logError("file: "__FILE__", line: %d, "
+				"invalid local ip address: %s",
+				__LINE__, local_ip);
+			context->fd = -1;
+			return EINVAL;
+		}
+
+		printf("ip_addr: %s, s_addr: %08X\n", local_ip, ip_addr.s_addr);
+		printf("mask number: %08X\n", (1 << mid_bits));
+
+		mid = (ip_addr.s_addr >> (32 - mid_bits))  & ((1 << mid_bits) - 1);
+	}
+
+	if ((context->fd = open(filename, O_RDWR | O_CREAT, 0644)) < 0)
+	{
+		result = errno != 0 ? errno : EACCES;
+		logError("file: "__FILE__", line: %d, "
+			"open file \"%s\" fail, "
+			"errno: %d, error info: %s", __LINE__,
+			filename, result, STRERROR(result));
+		return result;
+	}
+
+	context->machine_id = mid;
+	context->mid_bits = mid_bits;
+	context->sn_bits = 32 - mid_bits;
+	context->masked_mid = ((int64_t)mid) << context->sn_bits;
+	context->sn_mask = ((int64_t)1 << context->sn_bits) - 1;
+
+	printf("mid: %08X, masked_mid: %016llX, sn_mask: %08llX\n", mid, context->masked_mid, context->sn_mask);
+
+	return 0;
+}
+
+void id_generator_destroy(struct idg_context *context)
+{
+	if (context->fd >= 0)
+	{
+		close(context->fd);
+		context->fd = -1;
+	}
+}
+
+int id_generator_next(struct idg_context *context, int64_t *id)
+{
+	int result;
+	int len;
+	int bytes;
+	int64_t sn;
+	char buff[32];
+	char *endptr;
+
+	if ((result=file_write_lock(context->fd)) != 0)
+	{
+		return result;
+	}
+
+	do
+	{
+		if (lseek(context->fd, 0L, SEEK_SET) == -1)
+		{
+			result = errno != 0 ? errno : EACCES;
+			logError("file: "__FILE__", line: %d, "
+				"file lseek fail, "
+				"errno: %d, error info: %s", __LINE__,
+				result, STRERROR(result));
+			sn = 0;
+			break;
+		}
+
+		if ((bytes=read(context->fd, buff, sizeof(buff) - 1)) < 0)
+		{
+			result = errno != 0 ? errno : EACCES;
+			logError("file: "__FILE__", line: %d, "
+				"file read fail, "
+				"errno: %d, error info: %s", __LINE__,
+				result, STRERROR(result));
+			sn = 0;
+			break;
+		}
+		*(buff + bytes) = '\0';
+
+		sn = strtoll(buff, &endptr, 10);
+		++sn;
+
+		if (lseek(context->fd, 0L, SEEK_SET) == -1)
+		{
+			result = errno != 0 ? errno : EACCES;
+			logError("file: "__FILE__", line: %d, "
+				"cal lseek fail, "
+				"errno: %d, error info: %s", __LINE__,
+				result, STRERROR(result));
+			break;
+		}
+
+		len = sprintf(buff, "%019"PRId64, sn);
+		if ((bytes=write(context->fd, buff, len)) != len)
+		{
+			result = errno != 0 ? errno : EACCES;
+			logError("file: "__FILE__", line: %d, "
+				"file write %d bytes fail, written: %d bytes, "
+				"errno: %d, error info: %s", __LINE__,
+				len, bytes, result, STRERROR(result));
+			break;
+		}
+	} while (0);
+
+	file_unlock(context->fd);
+
+	*id = (time(NULL) << 32) | context->masked_mid | (sn & context->sn_mask);
+	return result;
+}
+

src/id_generator.h

@@ -0,0 +1,84 @@
+/**
+* Copyright (C) 2008 Happy Fish / YuQing
+*
+* FastDFS may be copied only under the terms of the GNU General
+* Public License V3, which may be found in the FastDFS source kit.
+* Please visit the FastDFS Home Page http://www.csource.org/ for more detail.
+**/
+
+/**
+  64 bits id generator for multi processes, the generated id format:
+  32 bits timestamp + X bits machine id  + Y bits serial number
+*/
+
+#ifndef ID_GENERATOR_H
+#define ID_GENERATOR_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <inttypes.h>
+#include "common_define.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct idg_context {
+    int fd;
+    int machine_id;
+    int mid_bits;   //bits of machine id
+    int sn_bits;    //bits of serial number
+    int64_t masked_mid;
+    int64_t sn_mask;
+};
+
+/**
+* init function
+    set mid_bits to 16
+    set machine_id to 2 bytes of local ip address
+* parameter:
+*   context: the id generator context
+*   filename: the filename to store id
+* return error no, 0 for success, none zero for fail
+*/
+int id_generator_init(struct idg_context *context, const char *filename);
+
+/**
+* init function
+* parameter:
+*   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
+* 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);
+
+/**
+* init function
+* parameter:
+*   context: the id generator context
+*   filename: the filename to store id
+* return error no, 0 for success, none zero for fail
+*/
+void id_generator_destroy(struct idg_context *context);
+
+/**
+* generate next id
+* parameter:
+*   context: the id generator context
+*   id: store the id
+* return error no, 0 for success, none zero for fail
+*/
+int id_generator_next(struct idg_context *context, int64_t *id);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+

src/tests/Makefile

@@ -4,7 +4,8 @@ COMPILE = $(CC) -g -O1 -Wall -D_FILE_OFFSET_BITS=64 -g -DDEBUG_FLAG
 INC_PATH = -I/usr/include/fastcommon
 LIB_PATH = -lfastcommon -lpthread
 
-ALL_PRGS = test_allocator test_skiplist test_multi_skiplist test_mblock test_blocked_queue
+ALL_PRGS = test_allocator test_skiplist test_multi_skiplist test_mblock test_blocked_queue \
+           test_id_generator
 
 all: $(ALL_PRGS)
 .c:

src/tests/test_id_generator.c

@@ -0,0 +1,48 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <time.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include "logger.h"
+#include "shared_func.h"
+#include "sched_thread.h"
+#include "ini_file_reader.h"
+#include "sockopt.h"
+#include "id_generator.h"
+
+int main(int argc, char *argv[])
+{
+	struct idg_context context;
+	int result;
+	int i;
+	int64_t id;
+	const int machine_id = 0;
+	const int mid_bits = 8;
+
+	result = id_generator_init_ex(&context, "/tmp/sn.txt",
+		machine_id, mid_bits);
+	if (result != 0)
+	{
+		return result;
+	}
+
+	id_generator_next(&context, &id);
+	printf("id: %"PRId64", %016llX\n", id, id);
+	for (i=0; i<1000000; i++)
+	{
+		result = id_generator_next(&context, &id);
+		if (result != 0)
+		{
+			break;
+		}
+	}
+	printf("id: %"PRId64", %016llX\n", id, id);
+
+	id_generator_destroy(&context);
+	return 0;
+}
+