[nginx source code analysis] Main function analysis

ngx_strerror_init

The main function is to first save the error information in the ngx_sys_errlist array and make a mapping array of errno->errmsg. When an error occurs in the system, errmsg can be found directly through errno, reducing api calls.

ngx_get_options(argc, argv)

This function mainly sets some flag variables based on user input and saves the parameters entered by the user.

Param		flag
?/h			ngx_show_version=1/ngx_show_help=1
v			ngx_show_version=1
V			ngx_show_version=1/ngx_show_configure=1
t			ngx_test_config=1
q			ngx_quiet_mode=1
p			ngx_prefix=argv[index]支持-p/home/work/nginx or –p /home/work/nginx
c			ngx_conf_file=p支持方式同上
g			ngx_conf_param=p	支持方式同上
s			ngx_signal=p/ngx_process=NGX_PROCESS_SIGNALLER(stop、quit、reopen、reload)

xngx_time_init- & gt; ngx_time_update

to update the following time

Rreee

ngx_regex_init ()

Mainly set two PCRE global allocation and recycling functions

ngx_pid = getpid (); //Get the pid of the main process

ngx_log_init(ngx_prefix)

variable									format
ngx_cached_time = tp;						
ngx_cached_http_time.data = p0;				“Mon, 28 Sep 1970 06:00:00 GMT”
ngx_cached_err_log_time.data = p1;			“1970/09/28 12:00:00”
ngx_cached_http_log_time.data = p2;			“28/Sep/1970:12:00:00 +0600”
ngx_cached_http_log_iso8601.data = p3		        “1970-09-28T12:00:00+06:00”

The final return value and the ngx_log constructed by the function

#if (NGX_WIN32)
     if (name[1] != ':') {
#else
     if (name[0] != '/') {
#endif

         if (prefix) {
             plen = ngx_strlen(prefix);//如果用户输入了-p prefix

         } else {
#ifdef NGX_PREFIX
             prefix = (u_char *) NGX_PREFIX;//用户没输入，使用configure路径
             plen = ngx_strlen(prefix);
#else
             plen = 0;
#endif
         }

         if (plen) {
             name = malloc(plen + nlen + 2);
             if (name == NULL) {
                 return NULL;
             }

             p = ngx_cpymem(name, prefix, plen);//copy prefix

             if (!ngx_path_separator(*(p - 1))) {
                 *p++ = '/';
             }

             ngx_cpystrn(p, (u_char *) NGX_ERROR_LOG_PATH, nlen + 1);//copy path

             p = name;
         }
     }

init_cycle.pool = ngx_create_pool(1024, log);//Allocate a memory pool node, specific memory Pool, you can

See the memory pool analysis document for details

ngx_save_argv

The function saves the parameters entered by the user in the ngx_argv array

ngx_process_options

This function mainly processes the parameters entered by the user, configuration files, test configuration files,

conf_file =/home/work/hunter/nginx/nginx_gdb/conf/nginx.conf

conf_prefix =/home/work/hunter/nginx/nginx_gdb/conf

prefix =/home/work/hunter/nginx/nginx_gdb

ngx_crc32_table_init()//Initialize the crc table

//Set the module index of each module

ngx_log
{
	ngx_log.file = &ngx_log_file;
	{
		ngx_fd_t		fd;//打开的错误日志
		ngx_str_t		name;//未设置
		u_char		*buffer;//未设置
		u_char		*pos;//未设置
		u_char		*last;//未设置
	}
	log_level = NGX_LOG_NOTICE;
}

Then analyze the configuration parsing

ngx_init_cycl()

The above introduces the [nginx source code analysis] main function analysis, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.