PHP source code analysis-PHP life cycle_PHP tutorial

The two most common operating modes of PHP are WEB mode and CLI mode.

No matter which mode, PHP works the same, running as a SAPI.

1. When we type the php command in the terminal, it uses the CLI.

It is like a web server to support PHP to complete the request. After the request is completed, control is returned to the terminal.

2. When using Apache as the host, when a request comes, PHP will support the completion of the request.

The following macros are defined in main/php.h

#define PHP_MINIT_FUNCTION ZEND_MODULE_STARTUP_D

#define PHP_MSHUTDOWN_FUNCTION ZEND_MODULE_SHUTDOWN_D

#define PHP_RINIT_FUNCTION ZEND_MODULE_ACTIVATE_D

#define PHP_RSHUTDOWN_FUNCTION ZEND_MODULE_DEACTIVATE_D

#define PHP_MINFO_FUNCTION ZEND_MODULE_INFO_D

#define PHP_GINIT_FUNCTION ZEND_GINIT_FUNCTION

#define PHP_GSHUTDOWN_FUNCTION ZEND_GSHUTDOWN_FUNCTION

The corresponding function is

PHP_MINIT_FUNCTION Run when initializing module

PHP_MSHUTDOWN_FUNCTION Run when module is uninstalled

PHP_RINIT_FUNCTION Runs when a REQUEST request is initialized

PHP_RSHUTDOWN_FUNCTION Runs when a REQUEST request ends

PHP_MINFO_FUNCTION This is to set the information of this module in phpinfo

PHP_GINIT_FUNCTION When initializing global variables

PHP_GSHUTDOWN_FUNCTION When releasing global variables

See a custom extension case snippet:

www.2cto.com

int minit_time;

PHP_MINIT_FUNCTION(test)

{

minit_time = time(NULL);

Return SUCCESS;

}

PHP_MSHUTDOWN_FUNCTION(test)

{

​ FILE *fp=fopen("mshutdown.txt","a+");

fprintf(fp,"%ldn",time(NULL));//Let us see if data will be appended to this file at the end of each request

fclose(fp);

Return SUCCESS;

}

int rinit_time;

PHP_RINIT_FUNCTION(test)

{

rinit_time = time(NULL);

Return SUCCESS;

}

PHP_RSHUTDOWN_FUNCTION(test)

{

​ FILE *fp=fopen("rshutdown.txt","a+");

fprintf(fp,"%ldn",time(NULL));//Let us see if data will be appended to this file at the end of each request

fclose(fp);

Return SUCCESS;

}

PHP_MINFO_FUNCTION(test)

{

php_info_print_table_start();//Call php_write to output HTML tags

​ php_info_print_table_header(2, "module info", "enabled");

php_info_print_table_end();//Call php_write to output HTML tags

/* Remove comments if you have entries in php.ini

DISPLAY_INI_ENTRIES();

*/

}

//Define the function test() that can be called in PHP and let it output the values ​​of minit_time and rinit_time on the page

PHP_FUNCTION(test)

{

​ php_printf("%d
",time_of_minit);

php_printf("%d
",time_of_rinit);

Return;

}

Take Apache as an example,

If working in multi-threaded mode:

In this mode, there is only one server process running, but many threads will run at the same time, which can reduce some resource overhead. Module init and Module shutdown only need to be run once, and some global variables only need to be initialized once. , because of the unique characteristics of threads, it is possible to conveniently share some data between requests.

The working method of multi-threading is as shown below

:

If working in multi-process mode:

The values ​​of minit_time and rinit_time change with each request.
Each time the page request ends, data will be written to time_rshutdown.txt and time_mshutdown.txt.

The following is a diagram of the multi-process working mode: