| |
| /* |
| * Copyright (C) Igor Sysoev |
| */ |
| |
| |
| #include <ngx_config.h> |
| #include <ngx_core.h> |
| #include <ngx_http.h> |
| |
| |
| |
| static ngx_int_t ngx_http_not_modified_filter_init(ngx_conf_t *cf); |
| |
| |
| static ngx_http_module_t ngx_http_not_modified_filter_module_ctx = { |
| NULL, /* preconfiguration */ |
| ngx_http_not_modified_filter_init, /* postconfiguration */ |
| |
| NULL, /* create main configuration */ |
| NULL, /* init main configuration */ |
| |
| NULL, /* create server configuration */ |
| NULL, /* merge server configuration */ |
| |
| NULL, /* create location configuration */ |
| NULL /* merge location configuration */ |
| }; |
| |
| |
| ngx_module_t ngx_http_not_modified_filter_module = { |
| NGX_MODULE_V1, |
| &ngx_http_not_modified_filter_module_ctx, /* module context */ |
| NULL, /* module directives */ |
| NGX_HTTP_MODULE, /* module type */ |
| NULL, /* init master */ |
| NULL, /* init module */ |
| NULL, /* init process */ |
| NULL, /* init thread */ |
| NULL, /* exit thread */ |
| NULL, /* exit process */ |
| NULL, /* exit master */ |
| NGX_MODULE_V1_PADDING |
| }; |
| |
| |
| static ngx_http_output_header_filter_pt ngx_http_next_header_filter; |
| |
| |
| static ngx_int_t |
| ngx_http_not_modified_header_filter(ngx_http_request_t *r) |
| { |
| time_t ims; |
| ngx_http_core_loc_conf_t *clcf; |
| |
| if (r->headers_out.status != NGX_HTTP_OK |
| || r != r->main |
| || r->headers_in.if_modified_since == NULL |
| || r->headers_out.last_modified_time == -1) |
| { |
| return ngx_http_next_header_filter(r); |
| } |
| |
| clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); |
| |
| if (clcf->if_modified_since == NGX_HTTP_IMS_OFF) { |
| return ngx_http_next_header_filter(r); |
| } |
| |
| ims = ngx_http_parse_time(r->headers_in.if_modified_since->value.data, |
| r->headers_in.if_modified_since->value.len); |
| |
| ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, |
| "http ims:%d lm:%d", ims, r->headers_out.last_modified_time); |
| |
| if (ims != r->headers_out.last_modified_time) { |
| |
| if (clcf->if_modified_since == NGX_HTTP_IMS_EXACT |
| || ims < r->headers_out.last_modified_time) |
| { |
| return ngx_http_next_header_filter(r); |
| } |
| } |
| |
| r->headers_out.status = NGX_HTTP_NOT_MODIFIED; |
| r->headers_out.status_line.len = 0; |
| r->headers_out.content_type.len = 0; |
| ngx_http_clear_content_length(r); |
| ngx_http_clear_accept_ranges(r); |
| |
| if (r->headers_out.content_encoding) { |
| r->headers_out.content_encoding->hash = 0; |
| r->headers_out.content_encoding = NULL; |
| } |
| |
| return ngx_http_next_header_filter(r); |
| } |
| |
| |
| static ngx_int_t |
| ngx_http_not_modified_filter_init(ngx_conf_t *cf) |
| { |
| ngx_http_next_header_filter = ngx_http_top_header_filter; |
| ngx_http_top_header_filter = ngx_http_not_modified_header_filter; |
| |
| return NGX_OK; |
| } |