Linux/FreeBSD下用C语言开发PHP的so扩展模块例解
2008-02-17 17:27:25| 分类：
PHP | 标签：
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引用本文请注明出处：Just Do IT (http://www.toplee.com) < Michael Lee @ toplee.com >
我从97年接触互联网的web开发，至今已经过去9年了，从最初的frontpage做html页面到学会ASP+access+IIS开始，就跟web开发干上了，后来又依次使用了ASP+SQLServer+IIS、JSP+Oracle+Jrun(Resin/Tomcat)、PHP+Syabse(MySQL)+Apache … 最后我定格到了 PHP+MySQL+Apache+Linux(BSD) 的架构上，也就是大家常说的LAMP架构，这说来有很多理由，网上也有很多人讨论各种架构和开发语言之间的优劣，我就不多说了，简单说一下我喜欢LAMP的几个主要原因：
1、全开放的免费平台；
2、简单易上手、各种资源丰富；
3、PHP、MySQL、Apache与Linux(BSD)系统底层以及彼此间无缝结合，非常高效；
4、均使用最高效的语言C/C++开发，性能可靠；
5、PHP语言和C的风格基本一致，还吸取了Java和C++的诸多架构优点；
6、这是最关键的一点，那就是PHP可以非常方便的使用C/C++开发扩展模块，给了PHP无限的扩张性！
基于以上原因，我非常喜欢基于PHP语言的架构，其中最关键的一点就是最后一点，以前在Yahoo和mop均推广使用这个平台，在C扩展php方面也有一些经验，在此和大家分享一下，希望可以抛砖引玉。
用C语言编写PHP的扩展模块的方法有几种，根据最后的表现形式有两种，一种是直接编译进php，一种是编译为php的so扩展模块来被php调用，另外根据编译的方式有两种，一种使用phpize工具（php编译后有的），一种使用ext_skel工具（php自带的），我们使用最多，也是最方便的方式就是使用ext_skel工具来编写php的so扩展模块，这里也主要介绍这种方式。
我们在php的源码目录里面可以看到有个ext目录（我这里说的php都是基于Linux平台的php来说的，不包括windows下的），在ext目录下有个工具 ext_skel ，这个工具可以让我们简单的开发出php的扩展模块，它提供了一个通用的php扩展模块开发步骤和模板。下面我们以开发一个在php里面进行utf8/gbk/gb2312三种编码转换的扩展模块为例子进行说明。在这个模块中，我们要最终提供以下几个函数接口：
(1) string toplee_big52gbk(string s)
将输入字符串从BIG5码转换成GBK
(2) string toplee_gbk2big5(string s)
将输入字符串从GBK转换成BIG5码
(3) string toplee_normalize_name(string s)
将输入字符串作以下处理：全角转半角，strim，大写转小写
(4) string toplee_fan2jian(int code, string s)
将输入的GBK繁体字符串转换成简体
(5) string toplee_decode_utf(string s)
将utf编码的字符串转换成UNICODE
(6) string toplee_decode_utf_gb(string s)
将utf编码的字符串转换成GB
(7) string toplee_decode_utf_big5(string s)
将utf编码的字符串转换成BIG5
(8) string toplee_encode_utf_gb(string s)
将输入的GBKf编码的字符串转换成utf编码
首先，我们进入ext目录下，运行下面命令：
#./ext_skel –extname=toplee
这时，php会自动在ext目录下为我们生成一个目录toplee，里面包含下面几个文件
.cvsignore
CREDITS
EXPERIMENTAL
config.m4
php_toplee.h
tests
toplee.c
toplee.php
其中最有用的就是config.m4和toplee.c文件
接下来我们修改config.m4文件
#vi ./config.m4
找到里面有类似这样几行
dnl Make sure that the comment is aligned:
dnl [ --with-toplee Include toplee support])
dnl Otherwise use enable:
dnl PHP_ARG_ENABLE(toplee, whether to enable toplee support,
dnl Make sure that the comment is aligned:
dnl [ --enable-toplee Enable toplee support])
上面的几行意思是说告诉php编译的使用使用那种方式加载我们的扩展模块toplee，我们使用–with-toplee的方式，于是我们修改为下面的样子
Make sure that the comment is aligned:
[ --with-toplee Include toplee support])
dnl Otherwise use enable:
dnl PHP_ARG_ENABLE(toplee, whether to enable toplee support,
dnl Make sure that the comment is aligned:
dnl [ --enable-toplee Enable toplee support])
然后我们要做的关键事情就是编写toplee.c，这个是我们编写模块的主要文件，如果您什么都不修改，其实也完成了一个php扩展模块的编写，里面有类似下面的几行代码
{
char *arg =
NULL;
int arg_len,
len;
char string[256];
if
(zend_parse_parameters(ZEND_NUM_ARGS()
TSRMLS_CC,
"s", &arg, &arg_len)
== FAILURE)
{
return;
}
len =
sprintf(string,
"Congratulations! You have successfully modified ext/%.78s/config.m4. Module %.78s is now compiled into PHP.",
"toplee",
arg);
RETURN_STRINGL(string,
len, 1);
}
如果我们在后面完成php的编译时把新的模块编译进去，那么我们就可以在php脚本中调用函数toplee()，它会输出一段字符串“Congratulations! You have successfully modified ext/toplee/config.m4. Module toplee is now compiled into PHP.”
下面是我们对toplee.c的修改，让其支持我们预先规划的功能和接口，下面是toplee.c的源代码
+----------------------------------------------------------------------+
| PHP Version 4 |
+----------------------------------------------------------------------+
| Copyright (c) 1997-2002 The PHP Group |
+----------------------------------------------------------------------+
| This source file is subject to version 2.02 of the PHP license, |
| that is bundled with this package in the file LICENSE, and is |
| available at through the world-wide-web at |
| http://www.php.net/license/2_02.txt. |
| If you did not receive a copy of the PHP license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@php.net so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Author: |
+----------------------------------------------------------------------+
$Id: header,v 1.10 2002/02/28 08:25:27 sebastian Exp $
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "php_gbk.h"
#include "toplee_util.h"
/* If you declare any globals in php_gbk.h uncomment this:
ZEND_DECLARE_MODULE_GLOBALS(gbk)
*/
/* True global resources - no need for thread safety here */
static int
le_gbk;
/* {{{ gbk_functions[]
*
* Every user visible function must have an entry in gbk_functions[].
*/
function_entry
gbk_functions[] =
{
PHP_FE(toplee_decode_utf,
NULL)
PHP_FE(toplee_decode_utf_gb,
NULL)
PHP_FE(toplee_decode_utf_big5,
NULL)
PHP_FE(toplee_encode_utf_gb,
NULL)
PHP_FE(toplee_big52gbk,
NULL)
PHP_FE(toplee_gbk2big5,
NULL)
PHP_FE(toplee_fan2jian,
NULL)
PHP_FE(toplee_normalize_name,
NULL)
{NULL,
NULL, NULL}
/* Must be the last line in gbk_functions[] */
};
/* }}} */
/* {{{ gbk_module_entry
*/
zend_module_entry
gbk_module_entry =
{
#if ZEND_MODULE_API_NO >=
20010901
STANDARD_MODULE_HEADER,
#endif
"gbk",
gbk_functions,
PHP_MINIT(gbk),
PHP_MSHUTDOWN(gbk),
PHP_RINIT(gbk),
/* Replace with NULL if there's nothing to do at request start */
PHP_RSHUTDOWN(gbk),
/* Replace with NULL if there's nothing to do at request end */
PHP_MINFO(gbk),
#if ZEND_MODULE_API_NO >=
20010901
"0.1",
/* Replace with version number for your extension */
#endif
STANDARD_MODULE_PROPERTIES
};
/* }}} */
#ifdef COMPILE_DL_GBK
ZEND_GET_MODULE(gbk)
#endif
/* {{{ PHP_INI
*/
/* Remove comments and fill if you need to have entries in php.ini*/
PHP_INI_BEGIN()
PHP_INI_ENTRY("gbk2uni",
"",
PHP_INI_SYSTEM,
NULL)
PHP_INI_ENTRY("uni2gbk",
"",
PHP_INI_SYSTEM,
NULL)
PHP_INI_ENTRY("uni2big5",
"",
PHP_INI_SYSTEM,
NULL)
PHP_INI_ENTRY("big52uni",
"",
PHP_INI_SYSTEM,
NULL)
PHP_INI_ENTRY("big52gbk",
"",
PHP_INI_SYSTEM,
NULL)
PHP_INI_ENTRY("gbk2big5",
"",
PHP_INI_SYSTEM,
NULL)
// STD_PHP_INI_ENTRY("gbk.global_value", "42", PHP_INI_ALL, OnUpdateInt, global_value, zend_gbk_globals, gbk_globals)
// STD_PHP_INI_ENTRY("gbk.global_string", "foobar", PHP_INI_ALL, OnUpdateString, global_string, zend_gbk_globals, gbk_globals)
PHP_INI_END()
/* }}} */
/* {{{ php_gbk_init_globals
*/
/* Uncomment this function if you have INI entries
static void php_gbk_init_globals(zend_gbk_globals *gbk_globals)
{
gbk_globals->global_value = 0;
gbk_globals->global_string = NULL;
}
*/
/* }}} */
char gbk2uni_file[256];
char uni2gbk_file[256];
char big52uni_file[256];
char uni2big5_file[256];
char gbk2big5_file[256];
char big52gbk_file[256];
//utf file init flag
static int
initutf=0;
/* {{{ PHP_MINIT_FUNCTION
*/
PHP_MINIT_FUNCTION(gbk)
{
/* If you have INI entries, uncomment these lines
ZEND_INIT_MODULE_GLOBALS(gbk, php_gbk_init_globals, NULL);*/
REGISTER_INI_ENTRIES();
memset(gbk2uni_file,
0, sizeof(gbk2uni_file));
memset(uni2gbk_file,
0, sizeof(uni2gbk_file));
memset(big52uni_file,
0, sizeof(big52uni_file));
memset(uni2big5_file,
0, sizeof(uni2big5_file));
memset(gbk2big5_file,
0, sizeof(gbk2big5_file));
memset(big52gbk_file,
0, sizeof(big52gbk_file));
strncpy(gbk2uni_file,
INI_STR("gbk2uni"),
sizeof(gbk2uni_file)-1);
strncpy(uni2gbk_file,
INI_STR("uni2gbk"),
sizeof(uni2gbk_file)-1);
strncpy(big52uni_file,
INI_STR("big52uni"),
sizeof(big52uni_file)-1);
strncpy(uni2big5_file,
INI_STR("uni2big5"),
sizeof(uni2big5_file)-1);
strncpy(gbk2big5_file,
INI_STR("gbk2big5"),
sizeof(uni2big5_file)-1);
strncpy(big52gbk_file,
INI_STR("big52gbk"),
sizeof(uni2big5_file)-1);
//InitMMResource();
InitResource();
if ((uni2gbk_file[0]
== '\0') ||
(uni2big5_file[0] == '\0')
|| (gbk2big5_file[0] == '\0')
|| (big52gbk_file[0] == '\0')
|| (gbk2uni_file[0] == '\0')
|| (big52uni_file[0] == '\0'))
{
return
FAILURE;
}
if (gbk2uni_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_GBK2UNI,
gbk2uni_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
if (uni2gbk_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_UNI2GBK,
uni2gbk_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
if (big52uni_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_BIG52UNI,
big52uni_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
if (uni2big5_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_UNI2BIG5,
uni2big5_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
if (gbk2big5_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_GBK2BIG5,
gbk2big5_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
if (big52gbk_file[0]
!= '\0')
{
if
(LoadOneCodeTable(CODE_BIG52GBK,
big52gbk_file) !=
NULL)
{
toplee_cleanup_mmap(NULL);
return
FAILURE;
}
}
initutf =
1;
return
SUCCESS;
}
/* }}} */
/* {{{ PHP_MSHUTDOWN_FUNCTION
*/
PHP_MSHUTDOWN_FUNCTION(gbk)
{
/* uncomment this line if you have INI entries*/
UNREGISTER_INI_ENTRIES();
toplee_cleanup_mmap(NULL);
return
SUCCESS;
}
/* }}} */
/* Remove if there's nothing to do at request start */
/* {{{ PHP_RINIT_FUNCTION
*/
PHP_RINIT_FUNCTION(gbk)
{
return
SUCCESS;
}
/* }}} */
/* Remove if there's nothing to do at request end */
/* {{{ PHP_RSHUTDOWN_FUNCTION
*/
PHP_RSHUTDOWN_FUNCTION(gbk)
{
return
SUCCESS;
}
/* }}} */
/* {{{ PHP_MINFO_FUNCTION
*/
PHP_MINFO_FUNCTION(gbk)
{
php_info_print_table_start();
php_info_print_table_header(2,
"gbk support",
"enabled");
php_info_print_table_end();
/* Remove comments if you have entries in php.ini*/
DISPLAY_INI_ENTRIES();
}
/* }}} */
/* Remove the following function when you have succesfully modified config.m4
so that your module can be compiled into PHP, it exists only for testing
purposes. */
/* {{{ proto toplee_decode_utf(string s)
*/
PHP_FUNCTION(toplee_decode_utf)
{
char *s =
NULL, *t=NULL;
int argc =
ZEND_NUM_ARGS();
int s_len;
if (zend_parse_parameters(argc
TSRMLS_CC,
"s", &s, &s_len)
== FAILURE)
return;
if (!initutf)
RETURN_FALSE
t = strdup(s);
if (t==NULL)
RETURN_FALSE
DecodePureUTF(t,
KEEP_UNICODE);
RETVAL_STRING(t,1);
free(t);
return;
}
/* }}} */
/* {{{ proto toplee_decode_utf_gb(string s)
*/
PHP_FUNCTION(toplee_decode_utf_gb)
{
char *s =
NULL, *t=NULL;
int argc =
ZEND_NUM_ARGS();
int s_len;
if (zend_parse_parameters(argc
TSRMLS_CC,
"s", &s, &s_len)
== FAILURE)
return;
if (!initutf)
RETURN_FALSE
t = strdup(s);
if (t==NULL)
RETURN_FALSE
DecodePureUTF(t,
DECODE_UNICODE);
RETVAL_STRING(t,1);
free(t);
return;
}
/* }}} */
/* {{{ proto toplee_decode_utf_big5(string s)
*/
PHP_FUNCTION(toplee_decode_utf_big5)
{
char *s =
NULL, *t=NULL;
int argc =
ZEND_NUM_ARGS();
int s_len;
if (zend_parse_parameters(argc
TSRMLS_CC,
"s", &s, &s_len)
== FAILURE)
return;
if (!initutf)
RETURN_FALSE
t = strdup(s);
if (t==NULL)
RETURN_FALSE
DecodePureUTF(t,
DECODE_UNICODE |
DECODE_BIG5);
RETVAL_STRING(t,1);
free(t);
return;
}
/* }}} */
int EncodePureUTF(unsigned
char* strSrc,
unsigned char*
strDst, int
nDstLen, int
nFlag)
{
int nRet;
int pos;
unsigned short
c;
unsigned short*
uBuf;
int nSize;
int nLen;
int nReturn;
nLen=strlen((const
char*)strSrc);
if(nDstLen <
nLen*2+1)
return
0;
nSize=nLen+1;
uBuf=(unsigned
short*)emalloc(sizeof(unsigned
short