diff options
Diffstat (limited to 'APACHE_1_3_42/src/modules/standard/mod_expires.c')
| -rw-r--r-- | APACHE_1_3_42/src/modules/standard/mod_expires.c | 473 |
1 files changed, 473 insertions, 0 deletions
diff --git a/APACHE_1_3_42/src/modules/standard/mod_expires.c b/APACHE_1_3_42/src/modules/standard/mod_expires.c new file mode 100644 index 0000000000..30bf8f5478 --- /dev/null +++ b/APACHE_1_3_42/src/modules/standard/mod_expires.c @@ -0,0 +1,473 @@ +/* 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 */ +}; + |