ngx_http_log_module.c文件

在nginx.conf中相关的指令为：

log_format proxyformat "$time_iso8601 $remote_addr:$remote_port $server_addr:$server_port $upstream_addr $request_time $upstream_response_time $status $upstream_status $request_length $body_bytes_sent \"$request_method $scheme://$http_host$request_uri $server_protocol\" \"$http_referer\" \"$http_user_agent\"";access_log syslog:facility=local3,severity=info,server=127.0.0.1:514,tag=tengine proxyformat;先关注log模块的初始化static ngx_http_module_t ngx_http_log_module_ctx = {NULL, /* preconfiguration */ngx_http_log_init, /* postconfiguration */ngx_http_log_create_main_conf, /* create main configuration */NULL, /* init main configuration */NULL, /* create server configuration */NULL, /* merge server configuration */ngx_http_log_create_loc_conf, /* create location configuration */ngx_http_log_merge_loc_conf /* merge location configuration */};static void *ngx_http_log_create_main_conf(ngx_conf_t *cf){ngx_http_log_main_conf_t *conf;ngx_http_log_fmt_t *fmt;conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_log_main_conf_t));if (conf == NULL) {return NULL;}// 初始化formatif (ngx_array_init(&conf->formats, cf->pool, 4, sizeof(ngx_http_log_fmt_t))!= NGX_OK){return NULL;}return conf;}static ngx_int_tngx_http_log_init(ngx_conf_t *cf){// 这块有判断是否使用默认的combine的逻辑，在tengine中，自定义了一波，所以不care// 将handler加入log阶段cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);h = ngx_array_push(&cmcf->phases[NGX_HTTP_LOG_PHASE].handlers);if (h == NULL) {return NGX_ERROR;}*h = ngx_http_log_handler;return NGX_OK;}而在log_format指令的处理函数中，将这个fmt给保存下来static char *ngx_http_log_set_format(ngx_conf_t *cf, ngx_command_t *cmd, void *conf){// 获取loc_main_confngx_http_log_main_conf_t *lmcf = conf;// 初始化fmtfmt = lmcf->formats.elts;fmt = ngx_array_push(&lmcf->formats);if (fmt == NULL) {return NGX_CONF_ERROR;}// 赋值namefmt->name = value[1];// 初始化flushes和opsfmt->flushes = ngx_array_create(cf->pool, 4, sizeof(ngx_int_t));if (fmt->flushes == NULL) {return NGX_CONF_ERROR;}fmt->ops = ngx_array_create(cf->pool, 16, sizeof(ngx_http_log_op_t));if (fmt->ops == NULL) {return NGX_CONF_ERROR;}// 最后把整个日志格式编译return ngx_http_log_compile_format(cf, fmt->flushes, fmt->ops, cf->args, 2);}static char *ngx_http_log_compile_format(ngx_conf_t *cf, ngx_array_t *flushes,ngx_array_t *ops, ngx_array_t *args, ngx_uint_t s){// 遍历所有的argsfor ( /* void */ ; s < args->nelts; s++) {// 在已有的ngx_http_log_vars中看有没有指定的日志格式for (v = ngx_http_log_vars; v->name.len; v++) {if (v->name.len == var.len&& ngx_strncmp(v->name.data, var.data, var.len) == 0){// 将对应的方法，长度赋值给对应op，等待写入op->len = v->len;op->getlen = NULL;op->run = v->run;op->data = 0;goto found;}}// 没有的话则调用该函数if (ngx_http_log_variable_compile(cf, op, &var) != NGX_OK) {return NGX_CONF_ERROR;}if (len) {op->len = len;op->getlen = NULL;// 如果长度小的话，就直接用data来记录if (len <= sizeof(uintptr_t)) {op->run = ngx_http_log_copy_short;op->data = 0;// 记录datawhile (len--) {op->data <<= 8;op->data |= data[len];}// 比较长的话，记录成指针来指向，函数也是获取指针来进行获取值} else {op->run = ngx_http_log_copy_long;p = ngx_pnalloc(cf->pool, len);if (p == NULL) {return NGX_CONF_ERROR;}ngx_memcpy(p, data, len);op->data = (uintptr_t) p;}}}static ngx_int_tngx_http_log_variable_compile(ngx_conf_t *cf, ngx_http_log_op_t *op,ngx_str_t *value){ngx_int_t index;index = ngx_http_get_variable_index(cf, value);op->len = 0;op->getlen = ngx_http_log_variable_getlen;op->run = ngx_http_log_variable;op->data = index;}// 而这些可以进入日志中的参数，则是在core_preconfiguration函数中的ngx_http_variables_add_core_vars函数ngx_int_tngx_http_variables_add_core_vars(ngx_conf_t *cf){cmcf->variables_keys = ngx_pcalloc(cf->temp_pool,sizeof(ngx_hash_keys_arrays_t));for (cv = ngx_http_core_variables; cv->name.len; cv++) {v = ngx_palloc(cf->pool, sizeof(ngx_http_variable_t));if (v == NULL) {return NGX_ERROR;}*v = *cv;rc = ngx_hash_add_key(cmcf->variables_keys, &v->name, v,NGX_HASH_READONLY_KEY);if (rc == NGX_OK) {continue;}if (rc == NGX_BUSY) {ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,"conflicting variable name \"%V\"", &v->name);}return NGX_ERROR;}接下来可以看下整个的ngx_http_core_variablesstatic ngx_http_variable_t ngx_http_core_variables[] = {{ ngx_string("http_host"), NULL, ngx_http_variable_header,offsetof(ngx_http_request_t, headers_in.host), 0, 0 },{ ngx_string("http_user_agent"), NULL, ngx_http_variable_header,offsetof(ngx_http_request_t, headers_in.user_agent), 0, 0 },{ ngx_string("http_referer"), NULL, ngx_http_variable_header,offsetof(ngx_http_request_t, headers_in.referer), 0, 0 },#if (NGX_HTTP_GZIP){ ngx_string("http_via"), NULL, ngx_http_variable_header,offsetof(ngx_http_request_t, headers_in.via), 0, 0 },#endif#if (NGX_HTTP_X_FORWARDED_FOR){ ngx_string("http_x_forwarded_for"), NULL, ngx_http_variable_headers,offsetof(ngx_http_request_t, headers_in.x_forwarded_for), 0, 0 },#endif{ ngx_string("http_cookie"), NULL, ngx_http_variable_cookies,offsetof(ngx_http_request_t, headers_in.cookies), 0, 0 },{ ngx_string("content_length"), NULL, ngx_http_variable_content_length,0, 0, 0 },{ ngx_string("content_type"), NULL, ngx_http_variable_header,offsetof(ngx_http_request_t, headers_in.content_type), 0, 0 },{ ngx_string("host"), NULL, ngx_http_variable_host, 0, 0, 0 },{ ngx_string("binary_remote_addr"), NULL,ngx_http_variable_binary_remote_addr, 0, 0, 0 },{ ngx_string("remote_addr"), NULL, ngx_http_variable_remote_addr, 0, 0, 0 },{ ngx_string("remote_port"), NULL, ngx_http_variable_remote_port, 0, 0, 0 },{ ngx_string("proxy_protocol_addr"), NULL,ngx_http_variable_proxy_protocol_addr, 0, 0, 0 },{ ngx_string("server_addr"), NULL, ngx_http_variable_server_addr, 0, 0, 0 },{ ngx_string("server_port"), NULL, ngx_http_variable_server_port, 0, 0, 0 },{ ngx_string("server_protocol"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, http_protocol), 0, 0 },{ ngx_string("scheme"), NULL, ngx_http_variable_scheme, 0, 0, 0 },{ ngx_string("https"), NULL, ngx_http_variable_https, 0, 0, 0 },{ ngx_string("full_request"), NULL, ngx_http_variable_full_request,0, 0, 0 },{ ngx_string("normalized_request"), NULL, ngx_http_variable_normalized_request,0, 0, 0 },{ ngx_string("request_uri"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, unparsed_uri), 0, 0 },{ ngx_string("raw_uri"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, raw_uri), 0, 0 },{ ngx_string("uri"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, uri),NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("document_uri"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, uri),NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("request"), NULL, ngx_http_variable_request_line, 0, 0, 0 },{ ngx_string("document_root"), NULL,ngx_http_variable_document_root, 0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("realpath_root"), NULL,ngx_http_variable_realpath_root, 0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("query_string"), NULL, ngx_http_variable_request,offsetof(ngx_http_request_t, args),NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("args"),ngx_http_variable_set_args,ngx_http_variable_request,offsetof(ngx_http_request_t, args),NGX_HTTP_VAR_CHANGEABLE|NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("is_args"), NULL, ngx_http_variable_is_args,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("request_filename"), NULL,ngx_http_variable_request_filename, 0,NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("server_name"), NULL, ngx_http_variable_server_name, 0, 0, 0 },{ ngx_string("request_method"), NULL,ngx_http_variable_request_method, 0,NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("remote_user"), NULL, ngx_http_variable_remote_user, 0, 0, 0 },{ ngx_string("bytes_sent"), NULL, ngx_http_variable_bytes_sent,0, 0, 0 },{ ngx_string("body_bytes_sent"), NULL, ngx_http_variable_body_bytes_sent,0, 0, 0 },{ ngx_string("pipe"), NULL, ngx_http_variable_pipe,0, 0, 0 },{ ngx_string("request_completion"), NULL,ngx_http_variable_request_completion,0, 0, 0 },{ ngx_string("request_body"), NULL,ngx_http_variable_request_body,0, 0, 0 },{ ngx_string("request_body_file"), NULL,ngx_http_variable_request_body_file,0, 0, 0 },{ ngx_string("request_length"), NULL, ngx_http_variable_request_length,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("request_time"), NULL, ngx_http_variable_request_time,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("status"), NULL,ngx_http_variable_status, 0,NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("sent_http_content_type"), NULL,ngx_http_variable_sent_content_type, 0, 0, 0 },{ ngx_string("sent_http_content_length"), NULL,ngx_http_variable_sent_content_length, 0, 0, 0 },{ ngx_string("sent_http_location"), NULL,ngx_http_variable_sent_location, 0, 0, 0 },{ ngx_string("sent_http_last_modified"), NULL,ngx_http_variable_sent_last_modified, 0, 0, 0 },{ ngx_string("sent_http_connection"), NULL,ngx_http_variable_sent_connection, 0, 0, 0 },{ ngx_string("sent_http_keep_alive"), NULL,ngx_http_variable_sent_keep_alive, 0, 0, 0 },{ ngx_string("sent_http_transfer_encoding"), NULL,ngx_http_variable_sent_transfer_encoding, 0, 0, 0 },{ ngx_string("sent_http_cache_control"), NULL, ngx_http_variable_headers,offsetof(ngx_http_request_t, headers_out.cache_control), 0, 0 },{ ngx_string("limit_rate"), ngx_http_variable_request_set_size,ngx_http_variable_request_get_size,offsetof(ngx_http_request_t, limit_rate),NGX_HTTP_VAR_CHANGEABLE|NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("connection"), NULL,ngx_http_variable_connection, 0, 0, 0 },{ ngx_string("connection_requests"), NULL,ngx_http_variable_connection_requests, 0, 0, 0 },{ ngx_string("nginx_version"), NULL, ngx_http_variable_nginx_version,0, 0, 0 },{ ngx_string("hostname"), NULL, ngx_http_variable_hostname,0, 0, 0 },{ ngx_string("pid"), NULL, ngx_http_variable_pid,0, 0, 0 },{ ngx_string("msec"), NULL, ngx_http_variable_msec,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("dollar"), NULL, ngx_http_variable_dollar,0, 0, 0 },{ ngx_string("host_comment"), NULL, ngx_http_variable_host_comment,0, 0, 0 },{ ngx_string("unix_time"), NULL, ngx_http_variable_unix_time,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("year"), NULL, ngx_http_variable_year,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("year2"), NULL, ngx_http_variable_year2,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("month"), NULL, ngx_http_variable_month,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("day"), NULL, ngx_http_variable_day,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("hour"), NULL, ngx_http_variable_hour,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("hour12"), NULL, ngx_http_variable_hour12,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("minute"), NULL, ngx_http_variable_minute,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("second"), NULL, ngx_http_variable_second,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("time_iso8601"), NULL, ngx_http_variable_time_iso8601,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("time_local"), NULL, ngx_http_variable_time_local,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("time_http"), NULL, ngx_http_variable_time_http,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },#if (NGX_HAVE_TCP_INFO){ ngx_string("tcpinfo_rtt"), NULL, ngx_http_variable_tcpinfo,0, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("tcpinfo_rttvar"), NULL, ngx_http_variable_tcpinfo,1, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("tcpinfo_snd_cwnd"), NULL, ngx_http_variable_tcpinfo,2, NGX_HTTP_VAR_NOCACHEABLE, 0 },{ ngx_string("tcpinfo_rcv_space"), NULL, ngx_http_variable_tcpinfo,3, NGX_HTTP_VAR_NOCACHEABLE, 0 },#endif{ ngx_null_string, NULL, NULL, 0, 0, 0 }};这块是在ngx_http_variables_init_vars中初始化ngx_int_tngx_http_variables_init_vars(ngx_conf_t *cf){cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);v = cmcf->variables.elts;key = cmcf->variables_keys->keys.elts;for (i = 0; i < cmcf->variables.nelts; i++) {for (n = 0; n < cmcf->variables_keys->keys.nelts; n++) {av = key[n].value;if (v[i].name.len == key[n].key.len&& ngx_strncmp(v[i].name.data, key[n].key.data, v[i].name.len)== 0){// 将get_handler和data赋值过来v[i].get_handler = av->get_handler;v[i].data = av->data;}