PHP扩展开发-用魔术方法扩展session类
现在有一个简单的session类，来实现项目中session的统一管理.此session类可以设置session变量名前缀，使用魔术方法来注册和检查session变量，使用起来非常方便。代码如下：
<?php
/*
author：dengqiang
*/
class session {
private $prefix;
public function __construct($prefix) {
@session_start ();
$this->prefix = $prefix;
}
public function setPrefix() {
return $this->prefix;
}
public function getPrefix() {
return $this->prefix;
}
public function delete($name) {
if (isset ( $_SESSION [$this->prefix . $name] )) {
unset ( $_SESSION [$this->prefix . $name] );
}
}
public function __set($name, $value) {
$_SESSION [$this->prefix . $name] = $value;
}
public function __get($name) {
if (isset ( $_SESSION [$this->prefix . $name] )) {
return $_SESSION [$this->prefix . $name];
} else {
return null;
}
}
public function isset($name){
return isset($_SESSION [$this->prefix . $name]);
}
public function unset($name){
unset($_SESSION [$this->prefix . $name]);
return true;
}
}
?> 现在我们将此session类开发成php扩展类，类名为Mysession。使用到的相关ZEND宏和PHPAPI如下：
PS(session_status) //用于获取当前session状态
PS_ADD_VARL()//注册一个PS全局变量
PS_DEL_VARL()//删除PS全局变量
zend_delete_global_variable()//删除zend全局变量
php_set_session_var()//设置session变量
php_get_session_var
在php_mysession.h声明Mysession类和方法
PHP_METHOD(Mysession, __construct); PHP_METHOD(Mysession, setPrefix); PHP_METHOD(Mysession, getPrefix); PHP_METHOD(Mysession, delete); PHP_METHOD(Mysession, isset); PHP_METHOD(Mysession, unset); PHP_METHOD(Mysession, __set); PHP_METHOD(Mysession, __get);在mysession.c中实现Mysession类扩展
加载session头文件
#include "ext/session/php_session.h"
#define IF_SESSION_VARS() \
if (PS(http_session_vars) && PS(http_session_vars)->type == IS_ARRAY) 声明方法中的参数
ZEND_BEGIN_ARG_INFO(arg_construct,1) ZEND_ARG_INFO(0, prefix) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO(arg_setPrefix,1) ZEND_ARG_INFO(0, prefix) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO(arg_set,2) ZEND_ARG_INFO(0, name) ZEND_ARG_INFO(0, value) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO(arg_get,1) ZEND_ARG_INFO(0, name) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO(arg_isset,1) ZEND_ARG_INFO(0, name) ZEND_END_ARG_INFO() ZEND_BEGIN_ARG_INFO(arg_unset,1) ZEND_ARG_INFO(0, name) ZEND_END_ARG_INFO()
将Mysession类注册到zend内部
static zend_function_entry Mysession_class_functions[] = {
PHP_ME(Mysession, __construct , arg_construct, ZEND_ACC_CTOR | ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, setPrefix , arg_setPrefix, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, getPrefix ,NULL, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, delete ,NULL, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, isset ,arg_isset, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, unset ,arg_unset, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, __set , arg_set, ZEND_ACC_PUBLIC) /* For testing, remove later. */
PHP_ME(Mysession, __get ,arg_get, ZEND_ACC_PUBLIC) /* For testing, remove later. */
{NULL, NULL, NULL}
};
zend_class_entry *Mysession_ce;
PHP_MINIT_FUNCTION(mysession)
{
/* If you have INI entries, uncomment these lines
REGISTER_INI_ENTRIES();
*/
zend_class_entry Mysession;
INIT_CLASS_ENTRY(Mysession, "Mysession", Mysession_class_functions);
Mysession_ce = zend_register_internal_class_ex(&Mysession, NULL, NULL TSRMLS_CC);
zend_declare_property_null(Mysession_ce, ZEND_STRL("_prefix"), ZEND_ACC_PRIVATE TSRMLS_CC); //声明session前缀私有变量
return SUCCESS;
}
添加开发者信息
PHP_MINFO_FUNCTION(mysession)
{
php_info_print_table_start();
php_info_print_table_header(2, "mysession support", "enabled");
php_info_print_table_row(2, "author", "Dengqiang");
php_info_print_table_row(2, "version", "1.0");
php_info_print_table_end();
/* Remove comments if you have entries in php.ini
DISPLAY_INI_ENTRIES();
*/
} 实现Mysession类中方法
PHP_METHOD(Mysession, __construct)
{
char *prefix="";
int prefix_len=0;
if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "|s", &prefix, &prefix_len) == FAILURE){
return;
}
if(ZEND_NUM_ARGS()>0){
zend_update_property_string(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), prefix TSRMLS_CC);
}
if (PS(session_status) != php_session_active && PS(session_status) != php_session_disabled) {
php_session_start(TSRMLS_C);
}
RETURN_TRUE;
}
PHP_METHOD(Mysession, setPrefix)
{
char *prefix;
int prefix_len=0;
if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &prefix, &prefix_len) == FAILURE){
return;
}
if(prefix_len>0){
zend_update_property_string(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), prefix TSRMLS_CC);
RETURN_TRUE;
}
RETURN_FALSE;
}
PHP_METHOD(Mysession, getPrefix)
{
zval *zPrefix;
char *prefix;
zPrefix = zend_read_property(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), 0 TSRMLS_CC);
prefix = Z_STRVAL_P(zPrefix);
if(prefix != NULL){
RETURN_STRINGL(prefix, strlen(prefix), 0);
}
RETURN_NULL();
}
PHP_METHOD(Mysession, delete)
{
char *p_name;
int p_name_len;
char *session_name;
int session_name_len;
zval *zPrefix;
char *prefix;
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &p_name, &p_name_len) == FAILURE) {
return;
}
if (PS(session_status) == php_session_none) {
RETURN_FALSE;
}
zPrefix = zend_read_property(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), 0 TSRMLS_CC);
prefix = Z_STRVAL_P(zPrefix) == NULL ? "":Z_STRVAL_P(zPrefix);
session_name_len = spprintf(&session_name, 0, "%s%s", prefix, p_name);
IF_SESSION_VARS() {
SEPARATE_ZVAL_IF_NOT_REF(&PS(http_session_vars));
PS_DEL_VARL(session_name, session_name_len);
}
RETURN_TRUE;
}
PHP_METHOD(Mysession, isset)
{
zval *p_var;
char *p_name;
int p_name_len;
char *session_name;
int session_name_len;
zval *zPrefix;
char *prefix;
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &p_name, &p_name_len) == FAILURE) {
return;
}
if (PS(session_status) == php_session_none) {
RETURN_FALSE;
}
zPrefix = zend_read_property(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), 0 TSRMLS_CC);
prefix = Z_STRVAL_P(zPrefix);
session_name_len = spprintf(&session_name, 0, "%s%s", prefix, p_name);
IF_SESSION_VARS() {
if (zend_hash_find(Z_ARRVAL_P(PS(http_session_vars)), session_name, session_name_len+1, (void **)&p_var) == SUCCESS) {
RETURN_TRUE;
}
}
RETURN_FALSE;
}
PHP_METHOD(Mysession, unset)
{
if (PS(session_status) == php_session_none) {
RETURN_FALSE;
}
IF_SESSION_VARS() {
HashTable *ht_sess_var;
SEPARATE_ZVAL_IF_NOT_REF(&PS(http_session_vars));
ht_sess_var = Z_ARRVAL_P(PS(http_session_vars));
if (PG(register_globals)) {
uint str_len;
char *str;
ulong num_key;
HashPosition pos;
zend_hash_internal_pointer_reset_ex(ht_sess_var, &pos);
while (zend_hash_get_current_key_ex(ht_sess_var, &str, &str_len, &num_key, 0, &pos) == HASH_KEY_IS_STRING) {
zend_delete_global_variable(str, str_len - 1 TSRMLS_CC);
zend_hash_move_forward_ex(ht_sess_var, &pos);
}
}
/* Clean $_SESSION. */
zend_hash_clean(ht_sess_var);
}
}
PHP_METHOD(Mysession, __set)
{
zval *value = NULL;
char *name;
char *session_name;
int name_len,session_name_len;
zval *zPrefix;
char *prefix;
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sz", &name, &name_len, &value) == FAILURE) {
return;
}
if (PS(session_status) == php_session_none || PS(session_status) == php_session_disabled) {
RETURN_FALSE;
}
zPrefix = zend_read_property(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), 0 TSRMLS_CC);
prefix = Z_STRVAL_P(zPrefix) == NULL ? "":Z_STRVAL_P(zPrefix);
session_name_len = spprintf(&session_name, 0, "%s%s", prefix, name);
IF_SESSION_VARS() {
SEPARATE_ZVAL_IF_NOT_REF(&PS(http_session_vars));
PS_DEL_VARL(session_name, session_name_len);
}
php_set_session_var(session_name, session_name_len, value, NULL TSRMLS_CC);
PS_ADD_VARL(session_name, session_name_len);
}
PHP_METHOD(Mysession, __get)
{
zval **p_var;
char *name;
char *session_name;
int name_len,session_name_len;
zval *zPrefix;
char *prefix;
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &name, &name_len) == FAILURE) {
return;
}
if (PS(session_status) == php_session_none || PS(session_status) == php_session_disabled) {
RETURN_FALSE;
}
zPrefix = zend_read_property(Z_OBJCE_P(getThis()), getThis(), ZEND_STRL("_prefix"), 0 TSRMLS_CC);
prefix = Z_STRVAL_P(zPrefix) == NULL ? "":Z_STRVAL_P(zPrefix);
session_name_len = spprintf(&session_name, 0, "%s%s", prefix, name);
IF_SESSION_VARS() {
if (php_get_session_var(session_name, session_name_len, &p_var) == SUCCESS) {
*return_value = **p_var;
}
}
}
编译安装后重启php-fpm测试
<?php
$Mysession = new Mysession('test');
$Mysession->var1 = "string";
var_dump($Mysession->isset('var1'));
echo"<br>";
var_dump($Mysession->var1);
echo"<br>";
$Mysession->var2 = array("a"=>'kingsoft', "b"=>"dengqiang");
var_dump($Mysession->isset('var2'));
echo"<br>";
var_dump($Mysession->var2);
echo"<br>";
$Mysession->delete('var1');
var_dump($Mysession->var1);
echo"<br>";
$Mysession->unset();
var_dump($Mysession->var2);
结果:
整个Mysession类扩展已开发完毕，我们可以发现PHP扩展类和php程序自定义类是非常相似的。以魔术方法__set为例，在php程序中，它会将未定义的属性和值解析为第一个和第二个参数，在PHP扩展中__set方法同样是接收属性名称和属性值两个参数。还一点就是在扩展中构造方法开启一次session后在其他方法中无需再次开启，这与php程序中自定义Mysession类也是一致的。
不管是php中自定义类还是PHP内核扩展类，他们的工作机制都是一样的，php自定义类可以理解为PHP内核扩展类再次封装了一层，PHP内核扩展的意义也是少做一次php代码的解析。