PHP extension module structure

All PHP extensions follow a common structure

1. the header file contains (including all required macros and APIs). 2. c. Declare the export function. 3. Declare the Zend function block. I. header file inclusionBy default, a new php_extname.h header file is created through the extension created by ext_seketon. This file contains PHP. H, which imports the basic Zend macros and APIs.

Ii. Declare the export FunctionZend_function (my_function), which provides functions called in PHP. Expand this macro: void zif_my_function (outputs) void zif_my_function (int ht, zval * return_value, zval * this_ptr, int return_value_users, role * executor_globals); Parameter Function:

Parameters	Description
HT	The number of parameters received. Considering backward compatibility, zend_num_args () is used to replace ht.
Return_value	The return value passed to the PHP interface.
This_ptr	If this function is a method in the object, this_ptr returns the current object
Return_value_used	Indicates whether the function is returned to the PHP interface.
Executor_globals	Point to the global settings of the Zend engine.

3. Declare Zend function blocksCreate the zend_function_entry array and provide Zend as the PHP interface.

typedef struct _zend_function_entry {    char *fname;    void (*handler)(INTERNAL_FUNCTION_PARAMETERS);    unsigned char *func_arg_types;} zend_function_entry;

Parameters	Description
Fname	The name of the function provided to PhP. For example, mysql_connect
Handler	The pointer responsible for processing this interface function.
Func_arg_types	Mark parameters. It can be set to null.

static const zend_function_entry mysql_functions[] = {                PHP_FE(mysql_connect,  arginfo_mysql_connect)                PHP_FE(mysql_pconnect,  arginfo_mysql_pconnect)                PHP_FE(mysql_close,  arginfo__optional_mysql_link)                PHP_FE(mysql_select_db,  arginfo_mysql_select_db)     {NULL, NULL, NULL}}

The preceding section lists the zend_function_entry defined in the MySQL extension. {Null, null, null} indicates the end of the array.

Iv. Declare the Zend module Extension StructureThis block information must be stored in the zend_module_entry structure and contain necessary information about the module. For example, initialize the module function pointer, Module name, and version information.

struct _zend_module_entry {    unsigned short size;    unsigned int zend_api;    unsigned char zend_debug;    unsigned char zts;    char *name;    zend_function_entry *functions;    int (*module_startup_func)(INIT_FUNC_ARGS);    int (*module_shutdown_func)(SHUTDOWN_FUNC_ARGS);    int (*request_startup_func)(INIT_FUNC_ARGS);    int (*request_shutdown_func)(SHUTDOWN_FUNC_ARGS);    void (*info_func)(ZEND_MODULE_INFO_FUNC_ARGS);    char *version;    [more]};

typedef struct _zend_module_entry zend_module_entry;

Parameters	Description
Size, zend_api, zend_debug and ZTS	It is usually filled with standard_module_header,
Name	Extension name
Functions	Pointing to zend_functions_entry pointer
Module_startup_func	Function pointer called during module initialization. Used to put some initialization steps. If a fault occurs during initialization, return failure, and return success if successful. Declare An initialization function using zend_minit
Module_shutdown_func	The function pointer called when the module is disabled, which is used for one-time analysis steps. Such as releasing resources. Sucess is returned successfully, failure is returned if the request fails, and null is returned if the request is not used. Declare zend_mshutdown
Request_startup_func	Call this function before each request is processed. Successful sucess, failed failure, null is returned if not used. Declare to use zend_rinit. From the Web, this function is called every request.
Request_startup_func	This function is called before and after each request is processed. Successful sucess, failed failure, null is returned if not used. Declare to use zend_rinit.
Request_shutdown_func	Call this function after each request is processed. Successful sucess, failed failure, null is returned if not used. Declare zend_rshutdown.
Info_func	The information about this extension is printed when phpinfo () is called. This information is output by this function. Declare to use zend_minfo
Version	The extended string version number. If no version is available, use no_version_yet.
[More]	You can use the macro standard_module_properties_ex or standard_module_properties.

zend_module_entry firstmod_module_entry ={    STANDARD_MODULE_HEADER,    "New Module",    firstmod_functions,    NULL, NULL, NULL, NULL, NULL,    NO_VERSION_YET,    STANDARD_MODULE_PROPERTIES,};

This is a basic module structure. The module name is "new module" and the function list is firstmod_functions. the startup and shutdown functions are not set.
The following is a PHP extension file named test. Through the above introduction, we will have a clear understanding of PHP extension development steps by comparing the following code.

# Ifdef have_config_h # include "config. H "# endif/* contains Zend APIs, macros, and basic PHP built-in functions, such as php_trim */# include" php. H "# include" php_ini.h "# include" ext/standard/info. H "# include" php_test.h "/* enable the global variable in the module */zend_declare_module_globals (TEST)/* true global resources-no need for thread safety here */static int le_test; /** declare the Function Array and provide it to PhP using */const zend_function_entry test_functions [] = {php_fe (my_function, null)/* Testing, remove later. */php_fe_end/* must be the last line in test_functions [] */};/*} * // * module structure, declare Startup \ shutdown, Module name, and function */zend_module_entry test_module_entry ={# if zend_module_api_no> = 20010901 standard_module_header, # endif "test", test_functions, php_minit (test), php_mshutdown (test), php_rinit (test),/* replace with null if there's nothing to do at request start */php_rshu Tdown (test),/* replace with null if there's nothing to do at request end */php_minfo (test), # If zend_module_api_no> = 20010901 "0.1 ", /* replace with version number for your extension */# endif standard_module_properties}; # ifdef compile_dl_testzend_get_module (TEST) # endif/* from PHP. read configuration information in the ini configuration file */php_ini_begin () std_php_ini_entry ("test. global_value "," 42 ", php_ini_all, onupdatelong, global_value, ze Nd_test_globals, test_globals) std_php_ini_entry ("test. global_string "," foobar ", php_ini_all, onupdatestring, global_string, zend_test_globals, test_globals) php_ini_end ()/* initialize the default value of the global variable */static void merge) {test_globals-> global_value = 0; test_globals-> global_string = NULL;}/* is called when the module is loaded for the first time */php_minit_function (test) {/* register the global variable */register_ini_entries (); Return success;}/* call */php_mshutdown_function (TEST) {/* release global variable */unregister_ini_entries (); Return success ;} /* call */php_rinit_function (TEST) {return success;}/* call */php_rshutdown_function (TEST) {return success;} before each request ;} /* phpinfo () Output extension information */php_minfo_function (TEST) {php_info_print_table_start (); php_info_print_table_header (2, "test support", "enabled"); php_info_print_table_end (); /* Whether to lose Output PHP. configuration Information in ini display_ini_entries (); */}/* definition function my_function is provided to PhP using */php_function (my_function) {char * Arg = NULL; int arg_len, Len; char * strg; If (zend_parse_parameters (zend_num_args () tsrmls_cc, "S", & Arg, & arg_len) = failure) {return;} Len = spprintf (& strg, 0, "Congratulations! You have successfully modified EXT/%. 78 s/config. m4. module %. 78 s is now compiled into PHP. "," test ", ARG); return_stringl (strg, Len, 0 );}