| /* Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /* |
| * mod_expires.c |
| * version 0.0.11 |
| * status beta |
| * |
| * Andrew Wilson <Andrew.Wilson@cm.cf.ac.uk> 26.Jan.96 |
| * |
| * This module allows you to control the form of the Expires: header |
| * that Apache issues for each access. Directives can appear in |
| * configuration files or in .htaccess files so expiry semantics can |
| * be defined on a per-directory basis. |
| * |
| * DIRECTIVE SYNTAX |
| * |
| * Valid directives are: |
| * |
| * ExpiresActive on | off |
| * ExpiresDefault <code><seconds> |
| * ExpiresByType type/encoding <code><seconds> |
| * |
| * Valid values for <code> are: |
| * |
| * 'M' expires header shows file modification date + <seconds> |
| * 'A' expires header shows access time + <seconds> |
| * |
| * [I'm not sure which of these is best under different |
| * circumstances, I guess it's for other people to explore. |
| * The effects may be indistinguishable for a number of cases] |
| * |
| * <seconds> should be an integer value [acceptable to atoi()] |
| * |
| * There is NO space between the <code> and <seconds>. |
| * |
| * For example, a directory which contains information which changes |
| * frequently might contain: |
| * |
| * # reports generated by cron every hour. don't let caches |
| * # hold onto stale information |
| * ExpiresDefault M3600 |
| * |
| * Another example, our html pages can change all the time, the gifs |
| * tend not to change often: |
| * |
| * # pages are hot (1 week), images are cold (1 month) |
| * ExpiresByType text/html A604800 |
| * ExpiresByType image/gif A2592000 |
| * |
| * Expires can be turned on for all URLs on the server by placing the |
| * following directive in a conf file: |
| * |
| * ExpiresActive on |
| * |
| * ExpiresActive can also appear in .htaccess files, enabling the |
| * behaviour to be turned on or off for each chosen directory. |
| * |
| * # turn off Expires behaviour in this directory |
| * # and subdirectories |
| * ExpiresActive off |
| * |
| * Directives defined for a directory are valid in subdirectories |
| * unless explicitly overridden by new directives in the subdirectory |
| * .htaccess files. |
| * |
| * ALTERNATIVE DIRECTIVE SYNTAX |
| * |
| * Directives can also be defined in a more readable syntax of the form: |
| * |
| * ExpiresDefault "<base> [plus] {<num> <type>}*" |
| * ExpiresByType type/encoding "<base> [plus] {<num> <type>}*" |
| * |
| * where <base> is one of: |
| * access |
| * now equivalent to 'access' |
| * modification |
| * |
| * where the 'plus' keyword is optional |
| * |
| * where <num> should be an integer value [acceptable to atoi()] |
| * |
| * where <type> is one of: |
| * years |
| * months |
| * weeks |
| * days |
| * hours |
| * minutes |
| * seconds |
| * |
| * For example, any of the following directives can be used to make |
| * documents expire 1 month after being accessed, by default: |
| * |
| * ExpiresDefault "access plus 1 month" |
| * ExpiresDefault "access plus 4 weeks" |
| * ExpiresDefault "access plus 30 days" |
| * |
| * The expiry time can be fine-tuned by adding several '<num> <type>' |
| * clauses: |
| * |
| * ExpiresByType text/html "access plus 1 month 15 days 2 hours" |
| * ExpiresByType image/gif "modification plus 5 hours 3 minutes" |
| * |
| * --- |
| * |
| * Change-log: |
| * 29.Jan.96 Hardened the add_* functions. Server will now bail out |
| * if bad directives are given in the conf files. |
| * 02.Feb.96 Returns DECLINED if not 'ExpiresActive on', giving other |
| * expires-aware modules a chance to play with the same |
| * directives. [Michael Rutman] |
| * 03.Feb.96 Call tzset() before localtime(). Trying to get the module |
| * to work properly in non GMT timezones. |
| * 12.Feb.96 Modified directive syntax to allow more readable commands: |
| * ExpiresDefault "now plus 10 days 20 seconds" |
| * ExpiresDefault "access plus 30 days" |
| * ExpiresDefault "modification plus 1 year 10 months 30 days" |
| * 13.Feb.96 Fix call to table_get() with NULL 2nd parameter [Rob Hartill] |
| * 19.Feb.96 Call gm_timestr_822() to get time formatted correctly, can't |
| * rely on presence of HTTP_TIME_FORMAT in Apache 1.1+. |
| * 21.Feb.96 This version (0.0.9) reverses assumptions made in 0.0.8 |
| * about star/star handlers. Reverting to 0.0.7 behaviour. |
| * 08.Jun.96 allows ExpiresDefault to be used with responses that use |
| * the DefaultType by not DECLINING, but instead skipping |
| * the table_get check and then looking for an ExpiresDefault. |
| * [Rob Hartill] |
| * 04.Nov.96 'const' definitions added. |
| * |
| * TODO |
| * add support for Cache-Control: max-age=20 from the HTTP/1.1 |
| * proposal (in this case, a ttl of 20 seconds) [ask roy] |
| * add per-file expiry and explicit expiry times - duplicates some |
| * of the mod_cern_meta.c functionality. eg: |
| * ExpiresExplicit index.html "modification plus 30 days" |
| * |
| * BUGS |
| * Hi, welcome to the internet. |
| */ |
| |
| #include <ctype.h> |
| #include "httpd.h" |
| #include "http_config.h" |
| #include "http_log.h" |
| |
| typedef struct { |
| int active; |
| char *expiresdefault; |
| table *expiresbytype; |
| } expires_dir_config; |
| |
| /* from mod_dir, why is this alias used? |
| */ |
| #define DIR_CMD_PERMS OR_INDEXES |
| |
| #define ACTIVE_ON 1 |
| #define ACTIVE_OFF 0 |
| #define ACTIVE_DONTCARE 2 |
| |
| module MODULE_VAR_EXPORT expires_module; |
| |
| static void *create_dir_expires_config(pool *p, char *dummy) |
| { |
| expires_dir_config *new = |
| (expires_dir_config *) ap_pcalloc(p, sizeof(expires_dir_config)); |
| new->active = ACTIVE_DONTCARE; |
| new->expiresdefault = ""; |
| new->expiresbytype = ap_make_table(p, 4); |
| return (void *) new; |
| } |
| |
| static const char *set_expiresactive(cmd_parms *cmd, expires_dir_config * dir_config, int arg) |
| { |
| /* if we're here at all it's because someone explicitly |
| * set the active flag |
| */ |
| dir_config->active = ACTIVE_ON; |
| if (arg == 0) { |
| dir_config->active = ACTIVE_OFF; |
| }; |
| return NULL; |
| } |
| |
| /* check_code() parse 'code' and return NULL or an error response |
| * string. If we return NULL then real_code contains code converted |
| * to the cnnnn format. |
| */ |
| static char *check_code(pool *p, const char *code, char **real_code) |
| { |
| char *word; |
| char base = 'X'; |
| int modifier = 0; |
| int num = 0; |
| int factor = 0; |
| |
| /* 0.0.4 compatibility? |
| */ |
| if ((code[0] == 'A') || (code[0] == 'M')) { |
| *real_code = (char *)code; |
| return NULL; |
| }; |
| |
| /* <base> [plus] {<num> <type>}* |
| */ |
| |
| /* <base> |
| */ |
| word = ap_getword_conf(p, &code); |
| if (!strncasecmp(word, "now", 1) || |
| !strncasecmp(word, "access", 1)) { |
| base = 'A'; |
| } |
| else if (!strncasecmp(word, "modification", 1)) { |
| base = 'M'; |
| } |
| else { |
| return ap_pstrcat(p, "bad expires code, unrecognised <base> '", |
| word, "'", NULL); |
| }; |
| |
| /* [plus] |
| */ |
| word = ap_getword_conf(p, &code); |
| if (!strncasecmp(word, "plus", 1)) { |
| word = ap_getword_conf(p, &code); |
| }; |
| |
| /* {<num> <type>}* |
| */ |
| while (word[0]) { |
| /* <num> |
| */ |
| if (ap_isdigit(word[0])) { |
| num = atoi(word); |
| } |
| else { |
| return ap_pstrcat(p, "bad expires code, numeric value expected <num> '", |
| word, "'", NULL); |
| }; |
| |
| /* <type> |
| */ |
| word = ap_getword_conf(p, &code); |
| if (word[0]) { |
| /* do nothing */ |
| } |
| else { |
| return ap_pstrcat(p, "bad expires code, missing <type>", NULL); |
| }; |
| |
| factor = 0; |
| if (!strncasecmp(word, "years", 1)) { |
| factor = 60 * 60 * 24 * 365; |
| } |
| else if (!strncasecmp(word, "months", 2)) { |
| factor = 60 * 60 * 24 * 30; |
| } |
| else if (!strncasecmp(word, "weeks", 1)) { |
| factor = 60 * 60 * 24 * 7; |
| } |
| else if (!strncasecmp(word, "days", 1)) { |
| factor = 60 * 60 * 24; |
| } |
| else if (!strncasecmp(word, "hours", 1)) { |
| factor = 60 * 60; |
| } |
| else if (!strncasecmp(word, "minutes", 2)) { |
| factor = 60; |
| } |
| else if (!strncasecmp(word, "seconds", 1)) { |
| factor = 1; |
| } |
| else { |
| return ap_pstrcat(p, "bad expires code, unrecognised <type>", |
| "'", word, "'", NULL); |
| }; |
| |
| modifier = modifier + factor * num; |
| |
| /* next <num> |
| */ |
| word = ap_getword_conf(p, &code); |
| }; |
| |
| *real_code = ap_psprintf(p, "%c%d", base, modifier); |
| |
| return NULL; |
| } |
| |
| static const char *set_expiresbytype(cmd_parms *cmd, expires_dir_config * dir_config, char *mime, char *code) |
| { |
| char *response, *real_code; |
| |
| if ((response = check_code(cmd->pool, code, &real_code)) == NULL) { |
| ap_table_setn(dir_config->expiresbytype, mime, real_code); |
| return NULL; |
| }; |
| return ap_pstrcat(cmd->pool, |
| "'ExpiresByType ", mime, " ", code, "': ", response, NULL); |
| } |
| |
| static const char *set_expiresdefault(cmd_parms *cmd, expires_dir_config * dir_config, char *code) |
| { |
| char *response, *real_code; |
| |
| if ((response = check_code(cmd->pool, code, &real_code)) == NULL) { |
| dir_config->expiresdefault = real_code; |
| return NULL; |
| }; |
| return ap_pstrcat(cmd->pool, |
| "'ExpiresDefault ", code, "': ", response, NULL); |
| } |
| |
| static const command_rec expires_cmds[] = |
| { |
| {"ExpiresActive", set_expiresactive, NULL, DIR_CMD_PERMS, FLAG, |
| "Limited to 'on' or 'off'"}, |
| {"ExpiresBytype", set_expiresbytype, NULL, DIR_CMD_PERMS, TAKE2, |
| "a MIME type followed by an expiry date code"}, |
| {"ExpiresDefault", set_expiresdefault, NULL, DIR_CMD_PERMS, TAKE1, |
| "an expiry date code"}, |
| {NULL} |
| }; |
| |
| static void *merge_expires_dir_configs(pool *p, void *basev, void *addv) |
| { |
| expires_dir_config *new = (expires_dir_config *) ap_pcalloc(p, sizeof(expires_dir_config)); |
| expires_dir_config *base = (expires_dir_config *) basev; |
| expires_dir_config *add = (expires_dir_config *) addv; |
| |
| if (add->active == ACTIVE_DONTCARE) { |
| new->active = base->active; |
| } |
| else { |
| new->active = add->active; |
| }; |
| |
| if (add->expiresdefault != '\0') { |
| new->expiresdefault = add->expiresdefault; |
| }; |
| |
| new->expiresbytype = ap_overlay_tables(p, add->expiresbytype, |
| base->expiresbytype); |
| return new; |
| } |
| |
| static int add_expires(request_rec *r) |
| { |
| expires_dir_config *conf; |
| char *code; |
| time_t base; |
| time_t additional; |
| time_t expires; |
| char age[20]; |
| |
| if (ap_is_HTTP_ERROR(r->status)) /* Don't add Expires headers to errors */ |
| return DECLINED; |
| |
| if (r->main != NULL) /* Say no to subrequests */ |
| return DECLINED; |
| |
| conf = (expires_dir_config *) ap_get_module_config(r->per_dir_config, &expires_module); |
| if (conf == NULL) { |
| ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, r, |
| "internal error: %s", r->filename); |
| return SERVER_ERROR; |
| }; |
| |
| if (conf->active != ACTIVE_ON) |
| return DECLINED; |
| |
| /* we perhaps could use the default_type(r) in its place but that |
| * may be 2nd guesing the desired configuration... calling table_get |
| * with a NULL key will SEGV us |
| * |
| * I still don't know *why* r->content_type would ever be NULL, this |
| * is possibly a result of fixups being called in many different |
| * places. Fixups is probably the wrong place to be doing all this |
| * work... Bah. |
| * |
| * Changed as of 08.Jun.96 don't DECLINE, look for an ExpiresDefault. |
| */ |
| if (r->content_type == NULL) |
| code = NULL; |
| else |
| code = (char *) ap_table_get(conf->expiresbytype, |
| ap_field_noparam(r->pool, r->content_type)); |
| |
| if (code == NULL) { |
| /* no expires defined for that type, is there a default? */ |
| code = conf->expiresdefault; |
| |
| if (code[0] == '\0') |
| return OK; |
| }; |
| |
| /* we have our code */ |
| |
| switch (code[0]) { |
| case 'M': |
| if (r->finfo.st_mode == 0) { |
| /* file doesn't exist on disk, so we can't do anything based on |
| * modification time. Note that this does _not_ log an error. |
| */ |
| return DECLINED; |
| } |
| base = r->finfo.st_mtime; |
| additional = atoi(&code[1]); |
| break; |
| case 'A': |
| /* there's been some discussion and it's possible that |
| * 'access time' will be stored in request structure |
| */ |
| base = r->request_time; |
| additional = atoi(&code[1]); |
| break; |
| default: |
| /* expecting the add_* routines to be case-hardened this |
| * is just a reminder that module is beta |
| */ |
| ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, r, |
| "internal error: bad expires code: %s", r->filename); |
| return SERVER_ERROR; |
| }; |
| |
| expires = base + additional; |
| ap_snprintf(age, sizeof(age), "max-age=%d", |
| (int) expires - (int) r->request_time); |
| ap_table_mergen(r->headers_out, "Cache-Control", ap_pstrdup(r->pool, age)); |
| tzset(); /* redundant? called implicitly by localtime, |
| * at least under FreeBSD |
| */ |
| ap_table_setn(r->headers_out, "Expires", |
| ap_gm_timestr_822(r->pool, expires)); |
| return OK; |
| } |
| |
| module MODULE_VAR_EXPORT expires_module = |
| { |
| STANDARD_MODULE_STUFF, |
| NULL, /* initializer */ |
| create_dir_expires_config, /* dir config creater */ |
| merge_expires_dir_configs, /* dir merger --- default is to override */ |
| NULL, /* server config */ |
| NULL, /* merge server configs */ |
| expires_cmds, /* command table */ |
| NULL, /* handlers */ |
| NULL, /* filename translation */ |
| NULL, /* check_user_id */ |
| NULL, /* check auth */ |
| NULL, /* check access */ |
| NULL, /* type_checker */ |
| add_expires, /* fixups */ |
| NULL, /* logger */ |
| NULL, /* header parser */ |
| NULL, /* child_init */ |
| NULL, /* child_exit */ |
| NULL /* post read-request */ |
| }; |
| |