| |
| /* |
| * Copyright (C) Igor Sysoev |
| */ |
| |
| |
| #include <ngx_config.h> |
| #include <ngx_core.h> |
| #include <ngx_http.h> |
| |
| |
| typedef struct { |
| time_t expires; |
| } ngx_http_headers_conf_t; |
| |
| |
| #define NGX_HTTP_EXPIRES_UNSET -2147483647 |
| #define NGX_HTTP_EXPIRES_OFF -2147483646 |
| #define NGX_HTTP_EXPIRES_EPOCH -2147483645 |
| |
| |
| static ngx_int_t ngx_http_headers_filter_init(ngx_cycle_t *cycle); |
| static void *ngx_http_headers_create_conf(ngx_conf_t *cf); |
| static char *ngx_http_headers_merge_conf(ngx_conf_t *cf, |
| void *parent, void *child); |
| static char *ngx_http_headers_expires(ngx_conf_t *cf, ngx_command_t *cmd, |
| void *conf); |
| |
| |
| static ngx_command_t ngx_http_headers_filter_commands[] = { |
| |
| { ngx_string("expires"), |
| NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, |
| ngx_http_headers_expires, |
| NGX_HTTP_LOC_CONF_OFFSET, |
| 0, |
| NULL}, |
| |
| ngx_null_command |
| }; |
| |
| |
| static ngx_http_module_t ngx_http_headers_filter_module_ctx = { |
| NULL, /* preconfiguration */ |
| NULL, /* postconfiguration */ |
| |
| NULL, /* create main configuration */ |
| NULL, /* init main configuration */ |
| |
| NULL, /* create server configuration */ |
| NULL, /* merge server configuration */ |
| |
| ngx_http_headers_create_conf, /* create location configuration */ |
| ngx_http_headers_merge_conf /* merge location configuration */ |
| }; |
| |
| |
| ngx_module_t ngx_http_headers_filter_module = { |
| NGX_MODULE_V1, |
| &ngx_http_headers_filter_module_ctx, /* module context */ |
| ngx_http_headers_filter_commands, /* module directives */ |
| NGX_HTTP_MODULE, /* module type */ |
| ngx_http_headers_filter_init, /* init module */ |
| NULL /* init process */ |
| }; |
| |
| |
| static ngx_http_output_header_filter_pt ngx_http_next_header_filter; |
| |
| |
| static ngx_int_t |
| ngx_http_headers_filter(ngx_http_request_t *r) |
| { |
| size_t len; |
| ngx_uint_t i; |
| ngx_table_elt_t *expires, *cc; |
| ngx_http_headers_conf_t *conf; |
| |
| if (r->headers_out.status != NGX_HTTP_OK || r->main) { |
| return ngx_http_next_header_filter(r); |
| } |
| |
| conf = ngx_http_get_module_loc_conf(r, ngx_http_headers_filter_module); |
| |
| if (conf->expires != NGX_HTTP_EXPIRES_OFF) { |
| |
| expires = r->headers_out.expires; |
| |
| if (expires == NULL) { |
| |
| expires = ngx_list_push(&r->headers_out.headers); |
| if (expires == NULL) { |
| return NGX_ERROR; |
| } |
| |
| r->headers_out.expires = expires; |
| |
| expires->hash = 1; |
| expires->key.len = sizeof("Expires") - 1; |
| expires->key.data = (u_char *) "Expires"; |
| } |
| |
| len = sizeof("Mon, 28 Sep 1970 06:00:00 GMT"); |
| expires->value.len = len - 1; |
| |
| cc = r->headers_out.cache_control.elts; |
| |
| if (cc == NULL) { |
| |
| cc = ngx_list_push(&r->headers_out.headers); |
| if (cc == NULL) { |
| return NGX_ERROR; |
| } |
| |
| cc->hash = 1; |
| cc->key.len = sizeof("Cache-Control") - 1; |
| cc->key.data = (u_char *) "Cache-Control"; |
| |
| } else { |
| for (i = 1; i < r->headers_out.cache_control.nelts; i++) { |
| cc[i].hash = 0; |
| } |
| } |
| |
| if (conf->expires == NGX_HTTP_EXPIRES_EPOCH) { |
| expires->value.data = (u_char *) "Thu, 01 Jan 1970 00:00:01 GMT"; |
| |
| cc->value.len = sizeof("no-cache") - 1; |
| cc->value.data = (u_char *) "no-cache"; |
| |
| } else { |
| expires->value.data = ngx_palloc(r->pool, len); |
| if (expires->value.data == NULL) { |
| return NGX_ERROR; |
| } |
| |
| if (conf->expires == 0) { |
| ngx_memcpy(expires->value.data, ngx_cached_http_time.data, |
| ngx_cached_http_time.len + 1); |
| |
| cc->value.len = sizeof("max-age=0") - 1; |
| cc->value.data = (u_char *) "max-age=0"; |
| |
| } else { |
| ngx_http_time(expires->value.data, ngx_time() + conf->expires); |
| |
| if (conf->expires < 0) { |
| cc->value.len = sizeof("no-cache") - 1; |
| cc->value.data = (u_char *) "no-cache"; |
| |
| } else { |
| cc->value.data = ngx_palloc(r->pool, sizeof("max-age=") |
| + NGX_TIME_T_LEN + 1); |
| if (cc->value.data == NULL) { |
| return NGX_ERROR; |
| } |
| |
| cc->value.len = ngx_sprintf(cc->value.data, "max-age=%T", |
| conf->expires) |
| - cc->value.data; |
| |
| } |
| } |
| } |
| } |
| |
| return ngx_http_next_header_filter(r); |
| } |
| |
| |
| static ngx_int_t |
| ngx_http_headers_filter_init(ngx_cycle_t *cycle) |
| { |
| ngx_http_next_header_filter = ngx_http_top_header_filter; |
| ngx_http_top_header_filter = ngx_http_headers_filter; |
| |
| return NGX_OK; |
| } |
| |
| |
| static void * |
| ngx_http_headers_create_conf(ngx_conf_t *cf) |
| { |
| ngx_http_headers_conf_t *conf; |
| |
| conf = ngx_palloc(cf->pool, sizeof(ngx_http_headers_conf_t)); |
| if (conf == NULL) { |
| return NGX_CONF_ERROR; |
| } |
| |
| conf->expires = NGX_HTTP_EXPIRES_UNSET; |
| |
| return conf; |
| } |
| |
| |
| static char * |
| ngx_http_headers_merge_conf(ngx_conf_t *cf, void *parent, void *child) |
| { |
| ngx_http_headers_conf_t *prev = parent; |
| ngx_http_headers_conf_t *conf = child; |
| |
| if (conf->expires == NGX_HTTP_EXPIRES_UNSET) { |
| conf->expires = (prev->expires == NGX_HTTP_EXPIRES_UNSET) ? |
| NGX_HTTP_EXPIRES_OFF : prev->expires; |
| } |
| |
| return NGX_CONF_OK; |
| } |
| |
| |
| static char * |
| ngx_http_headers_expires(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) |
| { |
| ngx_http_headers_conf_t *hcf = conf; |
| |
| ngx_uint_t minus; |
| ngx_str_t *value; |
| |
| if (hcf->expires != NGX_HTTP_EXPIRES_UNSET) { |
| return "is duplicate"; |
| } |
| |
| value = cf->args->elts; |
| |
| if (ngx_strcmp(value[1].data, "epoch") == 0) { |
| hcf->expires = NGX_HTTP_EXPIRES_EPOCH; |
| return NGX_CONF_OK; |
| } |
| |
| if (ngx_strcmp(value[1].data, "off") == 0) { |
| hcf->expires = NGX_HTTP_EXPIRES_OFF; |
| return NGX_CONF_OK; |
| } |
| |
| if (value[1].data[0] == '+') { |
| value[1].data++; |
| value[1].len--; |
| minus = 0; |
| |
| } else if (value[1].data[0] == '-') { |
| value[1].data++; |
| value[1].len--; |
| minus = 1; |
| |
| } else { |
| minus = 0; |
| } |
| |
| hcf->expires = ngx_parse_time(&value[1], 1); |
| |
| if (hcf->expires == NGX_ERROR) { |
| return "invalid value"; |
| } |
| |
| if (hcf->expires == NGX_PARSE_LARGE_TIME) { |
| return "value must be less than 68 years"; |
| } |
| |
| if (minus) { |
| hcf->expires = - hcf->expires; |
| } |
| |
| return NGX_CONF_OK; |
| } |