//解析filename中的配置项
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf;
ngx_conf_file_t *prev, conf_file;
enum {
parse_file = 0,
parse_block,
parse_param
} type;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) {
/* open configuration file */
//首先打开配置文件
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
//令cf->conf_file指向临时的conf_file结构体
prev = cf->conf_file;
cf->conf_file = &conf_file;
//获取配置文件的inode信息
if (ngx_fd_info(fd, &cf->conf_file->file.info) == -1) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
//我们将文件读取到cf->conf_file->buffer中
cf->conf_file->buffer = &buf;
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log);
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start;
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER;
buf.temporary = 1; //这是一个临时buf
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file;
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
type = parse_block;
} else {
type = parse_param;
}
//使用状态机方式解析配置项
for ( ;; ) {
//读取配置文件并解析, 每次返回NGX_OK，说明已经解析到一条配置项,
//我们会调用响应的回调函数进行处理
rc = ngx_conf_read_token(cf);
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) {
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
//如果碰到当前配置块的开始，则我们继续，否则返回失败
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
//在解析到配置项以后，如果自定义了handler函数则调用handler函数,
//否则调用默认的set方法设置参数
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
//调用cf->set方法设置配置项,一次只能设置一个配置项,当出现子模块时
//set方法会递归解析子模块,并进行配置
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
return NGX_CONF_ERROR;
}
cf->conf_file = prev;
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
/*
* 解析配置文件
*/
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf;
ngx_conf_file_t *prev, conf_file;
enum {
parse_file = 0,
parse_block,
parse_param
} type;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) { //新的配置文件
/* open configuration file */
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0); //打开文件
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
prev = cf->conf_file;
cf->conf_file = &conf_file;
if (ngx_fd_info(fd, &cf->conf_file->file.info) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
cf->conf_file->buffer = &buf;
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log); //默认4K的缓冲区
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start;
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER;
buf.temporary = 1;
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file;
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
type = parse_block;
} else {
type = parse_param;
}
for ( ;; ) {
rc = ngx_conf_read_token(cf); //读取配置项
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) {
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
if (rc == NGX_CONF_BLOCK_START) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"{\"");
goto failed;
}
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
/*解析配置项*/
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
/*配置文件协议完毕，释放相应数据空间*/
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
rc = NGX_ERROR;
}
cf->conf_file = prev;
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t *b;
ngx_uint_t block;
ngx_conf_file_t *prev;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) {
/* open configuration file */
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
prev = cf->conf_file;
cf->conf_file = ngx_palloc(cf->pool, sizeof(ngx_conf_file_t));
if (cf->conf_file == NULL) {
return NGX_CONF_ERROR;
}
if (ngx_fd_info(fd, &cf->conf_file->file.info) == -1) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
b = ngx_calloc_buf(cf->pool);
if (b == NULL) {
return NGX_CONF_ERROR;
}
cf->conf_file->buffer = b;
b->start = ngx_alloc(ngx_pagesize, cf->log);
if (b->start == NULL) {
return NGX_CONF_ERROR;
}
b->pos = b->start;
b->last = b->start;
b->end = b->last + ngx_pagesize;
b->temporary = 1;
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
block = 0;
} else {
block = 1;
}
for ( ;; ) {
rc = ngx_conf_read_token(cf);
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) {
if (!block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
block = 0;
}
if (rc == NGX_CONF_FILE_DONE && block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
if (rc != NGX_OK && rc != NGX_CONF_BLOCK_START) {
goto done;
}
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
if (filename) {
ngx_free(cf->conf_file->buffer->start);
cf->conf_file = prev;
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
cf->conf_file->file.name.data);
return NGX_CONF_ERROR;
}
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{ //第二个数为保存的配置文件路径的字符串，如/usr/local/nginx/conf/nginx.conf_file
char *rv;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf;
ngx_conf_file_t *prev, conf_file;
enum {
parse_file = 0,
parse_block,
parse_param
} type;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) { //指向一个配置文件路径字符串，需要函数ngx_conf_parse打开该文件并获取相关的文件信息
/* open configuration file */
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
prev = cf->conf_file;
cf->conf_file = &conf_file;
if (ngx_fd_info(fd, &cf->conf_file->file.info) == -1) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
cf->conf_file->buffer = &buf;
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log); //内存
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start; //初始值
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER; //4K，到末尾
buf.temporary = 1;
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file; //刚刚打开的新文件，包括include指令
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
//说明此时仅解析了部分解析，当遇到复杂配置项，比如events，http等，此时解析的内容还是来自当前文件
type = parse_block;
} else {
//正要开始解析命令行参数配置项值，在对用户通过命令行-g参数输入的配置信息进行解析，如nginx -g 'daemon on'
type = parse_param;
}
for ( ;; ) {
rc = ngx_conf_read_token(cf); //读取token，每次读取一个buffer
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) { //解析正常
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
if (cf->handler) { //进行这些token转换为Nginx内控制变量的值，针对“text/html html htm shtml”等这样的配置项或geo模块里的“192.168.0.0/16 local”这样的不定配置项，进行特殊的处理
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
rc = ngx_conf_handler(cf, rc); //配置转换
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
return NGX_CONF_ERROR;
}
cf->conf_file = prev;
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
//这个函数的详细解析
//请参看:http://www.pagefault.info/?p=188 nginx的启动流程分析(一)
// http://www.pagefault.info/?p=368
//第二个参数可以为空的，如果为空，则说明将要解析的是block中的内容或者param
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf;
ngx_conf_file_t *prev, conf_file;
enum {
parse_file = 0,
parse_block,
parse_param
} type;
// 经过这个宏
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) {
/* open configuration file */
// 打开配置文件
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
// NGX_INVALID_FILE 为宏定义，值为－1 ，定义在/os/unix/ngx_files.h 中
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
prev = cf->conf_file;
cf->conf_file = &conf_file;
// 获取配置文件的stat信息,并存储到cf->conf_file->file.info这个stat结构体中
// ngx_fd_info 这个函数是fstat这个函数的宏包装。参考./os/unix/ngx_files.h
if (ngx_fd_info(fd, &cf->conf_file->file.info) == -1) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
cf->conf_file->buffer = &buf;
// 申请一个NGX_CONF_BUFFER大小的buffer，用于 ngx_conf_read_token() 函数解析配置文件
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log);
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start;
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER;
buf.temporary = 1;
// 保存配置文件的基本信息
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file;
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
type = parse_block;
} else {
type = parse_param;
}
//循环遍历每一行配置文件，读取配置内容
for ( ;; ) {
//读入一个token，一般是一行
//读到的配置参数放到: (ngx_str_t*)(*((*cf).args)).elts
rc = ngx_conf_read_token(cf);
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) {
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
//判断cf是否有handler回调，如果有的话，优先调用handler回调，如果没有，则会进入ngx_conf_handler进行一般处理
//特别说一下，http的模块使用handler是ngx_http_block，具体请看ngx_http.c
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
//使用handler处理
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
//否则进入一般处理， 调用ngx_conf_handler对当前的token进行处理
// 参数中的rc 为ngx_read_conf_token的返回值
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
} //end for
failed:
rc = NGX_ERROR;
done:
//恢复现存、关闭已经打开的文件
//NGX_CONF_FILE_DONE 时必须要处理的部分
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
return NGX_CONF_ERROR;
}
cf->conf_file = prev;
}
// NGX_ERROR NGX_CONF_FILE_DONE NGX_CONF_BLOCK_DONE 时都需要处理的部分
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
u_char *p;
off_t size;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf, *tbuf;
ngx_conf_file_t *prev, conf_file;
ngx_conf_dump_t *cd;
enum {
parse_file = 0,
parse_block,
parse_param
} type;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) {
/* open configuration file */
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
prev = cf->conf_file;
cf->conf_file = &conf_file;
if (ngx_fd_info(fd, &cf->conf_file->file.info) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
cf->conf_file->buffer = &buf;
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log);
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start;
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER;
buf.temporary = 1;
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file;
if (ngx_dump_config
#if (NGX_DEBUG)
|| 1
#endif
)
{
p = ngx_pstrdup(cf->cycle->pool, filename);
if (p == NULL) {
goto failed;
}
size = ngx_file_size(&cf->conf_file->file.info);
tbuf = ngx_create_temp_buf(cf->cycle->pool, (size_t) size);
if (tbuf == NULL) {
goto failed;
}
cd = ngx_array_push(&cf->cycle->config_dump);
if (cd == NULL) {
goto failed;
}
cd->name.len = filename->len;
cd->name.data = p;
cd->buffer = tbuf;
cf->conf_file->dump = tbuf;
} else {
cf->conf_file->dump = NULL;
}
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
type = parse_block;
} else {
type = parse_param;
}
/*这里解析指令的方式是"读取一条、检查一条、解析一条"的方式解析配置文件，这里的一条是以分号或者花括号"{"、"}"为单位，如果遇到嵌套的花括号，则先处理嵌套的指令*/
for ( ;; ) {
/*将配置文件中当前的一条配置指令读取到内存中，判断配置语法是否使用正确，并将该指令保存到cycle->args数组中*/
rc = ngx_conf_read_token(cf);
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
if (rc == NGX_CONF_BLOCK_DONE) {
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
/*如果该指令定义了自定义处理函数，则调用自定义处理函数进行解析*/
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
if (rc == NGX_CONF_BLOCK_START) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"{\"");
goto failed;
}
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
/*调用指令的处理函数*/
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
rc = NGX_ERROR;
}
cf->conf_file = prev;
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
char *
ngx_conf_parse(ngx_conf_t *cf, ngx_str_t *filename)
{
char *rv;
u_char *p;
off_t size;
ngx_fd_t fd;
ngx_int_t rc;
ngx_buf_t buf, *tbuf;
ngx_conf_file_t *prev, conf_file;
ngx_conf_dump_t *cd;
enum {
parse_file = 0, //解析配置文件(初始配置文件解析)
parse_block, //解析配置文件中的块
parse_param //解析-g选项携带的参数
} type;
#if (NGX_SUPPRESS_WARN)
fd = NGX_INVALID_FILE;
prev = NULL;
#endif
if (filename) {
/* open configuration file */
/*打开配置文件nginx.conf*/
fd = ngx_open_file(filename->data, NGX_FILE_RDONLY, NGX_FILE_OPEN, 0);
if (fd == NGX_INVALID_FILE) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
ngx_open_file_n " \"%s\" failed",
filename->data);
return NGX_CONF_ERROR;
}
/*保存之前的cf->conf_file*/
prev = cf->conf_file;
cf->conf_file = &conf_file;
/*获取文件信息，如uid gid等*/
if (ngx_fd_info(fd, &cf->conf_file->file.info) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_EMERG, cf->log, ngx_errno,
ngx_fd_info_n " \"%s\" failed", filename->data);
}
/*
* 函数ngx_conf_read_token对配置文件内容逐个字符扫描并解析为单个的token，当然，该函数并不会频繁的去读取
* 配置文件，它每次从文件内读取足够多的内容以填满一个大小为NGX_CONF_BUFFER的缓存区（除了最后一次，即配置
* 文件剩余内容本来就不够了），这个缓存区在函数 ngx_conf_parse内申请并保存引用到变量cf->conf_file->buffer内，
* 函数 ngx_conf_read_token反复使用该缓存区
*/
/*构建cf->conf_file->buffer缓冲区*/
cf->conf_file->buffer = &buf;
buf.start = ngx_alloc(NGX_CONF_BUFFER, cf->log);
if (buf.start == NULL) {
goto failed;
}
buf.pos = buf.start;
buf.last = buf.start;
buf.end = buf.last + NGX_CONF_BUFFER;
buf.temporary = 1;
/*cf->conf_file指向当前配置文件/usr/local/nginx/conf/nginx.conf*/
cf->conf_file->file.fd = fd;
cf->conf_file->file.name.len = filename->len;
cf->conf_file->file.name.data = filename->data;
cf->conf_file->file.offset = 0;
cf->conf_file->file.log = cf->log;
cf->conf_file->line = 1;
type = parse_file;
/*复制一份配置文件*/
if (ngx_dump_config
#if (NGX_DEBUG)
|| 1
#endif
)
{
p = ngx_pstrdup(cf->cycle->pool, filename);
if (p == NULL) {
goto failed;
}
size = ngx_file_size(&cf->conf_file->file.info);
tbuf = ngx_create_temp_buf(cf->cycle->pool, (size_t) size);
if (tbuf == NULL) {
goto failed;
}
cd = ngx_array_push(&cf->cycle->config_dump);
if (cd == NULL) {
goto failed;
}
cd->name.len = filename->len;
cd->name.data = p;
cd->buffer = tbuf;
cf->conf_file->dump = tbuf;
} else {
cf->conf_file->dump = NULL;
}
} else if (cf->conf_file->file.fd != NGX_INVALID_FILE) {
type = parse_block;
} else {
type = parse_param;
}
for ( ;; ) {
/*
* 读取文件中的内容放到缓冲区中cf->conf_file->buffer，并进行解析，把解析的结果放到了cf->args 里面， 指令的每个单词都在数组中
* 占一个位置，比如 set debug off ，那么数组中存三个位置。
*/
rc = ngx_conf_read_token(cf);
/*
* ngx_conf_read_token() may return
*
* NGX_ERROR there is error
* NGX_OK the token terminated by ";" was found
* NGX_CONF_BLOCK_START the token terminated by "{" was found
* NGX_CONF_BLOCK_DONE the "}" was found
* NGX_CONF_FILE_DONE the configuration file is done
*/
if (rc == NGX_ERROR) {
goto done;
}
/*NGX_CONF_BLOCK_DONE解析块结束*/
if (rc == NGX_CONF_BLOCK_DONE) {
if (type != parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_FILE_DONE) {
if (type == parse_block) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"unexpected end of file, expecting \"}\"");
goto failed;
}
goto done;
}
if (rc == NGX_CONF_BLOCK_START) {
if (type == parse_param) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
"block directives are not supported "
"in -g option");
goto failed;
}
}
/* rc == NGX_OK || rc == NGX_CONF_BLOCK_START */
if (cf->handler) {
/*
* the custom handler, i.e., that is used in the http's
* "types { ... }" directive
*/
if (rc == NGX_CONF_BLOCK_START) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unexpected \"{\"");
goto failed;
}
rv = (*cf->handler)(cf, NULL, cf->handler_conf);
if (rv == NGX_CONF_OK) {
continue;
}
if (rv == NGX_CONF_ERROR) {
goto failed;
}
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, rv);
goto failed;
}
rc = ngx_conf_handler(cf, rc);
if (rc == NGX_ERROR) {
goto failed;
}
}
failed:
rc = NGX_ERROR;
done:
/*解析结束，恢复环境，关闭文件，释放内存*/
if (filename) {
if (cf->conf_file->buffer->start) {
ngx_free(cf->conf_file->buffer->start);
}
if (ngx_close_file(fd) == NGX_FILE_ERROR) {
ngx_log_error(NGX_LOG_ALERT, cf->log, ngx_errno,
ngx_close_file_n " %s failed",
filename->data);
rc = NGX_ERROR;
}
cf->conf_file = prev;
}
if (rc == NGX_ERROR) {
return NGX_CONF_ERROR;
}
return NGX_CONF_OK;
}
