This is mod_expires.c in view mode; [Download] [Up]
/* ====================================================================
* Copyright (c) 1995-1997 The Apache Group. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* 4. The names "Apache Server" and "Apache Group" must not be used to
* endorse or promote products derived from this software without
* prior written permission.
*
* 5. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE GROUP OR
* IT'S CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Group and was originally based
* on public domain software written at the National Center for
* Supercomputing Applications, University of Illinois, Urbana-Champaign.
* For more information on the Apache Group and the Apache HTTP server
* project, please see <http://www.apache.org/>.
*
*/
/*
* 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;
void *create_dir_expires_config (pool *p, char *dummy)
{
expires_dir_config *new =
(expires_dir_config *) pcalloc (p, sizeof(expires_dir_config));
new->active = ACTIVE_DONTCARE;
new->expiresdefault = "";
new->expiresbytype = make_table(p, 4);
return (void *)new;
}
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.
*/
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;
char foo[MAX_STRING_LEN];
/* 0.0.4 compatibility?
*/
if ( (code[0] == 'A') || (code[0] == 'M') ) {
*real_code = pstrdup( p, code );
return NULL;
};
/* <base> [plus] {<num> <type>}*
*/
/* <base>
*/
word = 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 pstrcat( p, "bad expires code, unrecognised <base> '",
word, "'", NULL);
};
/* [plus]
*/
word = getword_conf( p, &code );
if ( !strncasecmp( word, "plus", 1 ) ) {
word = getword_conf( p, &code );
};
/* {<num> <type>}*
*/
while ( word[0] ) {
/* <num>
*/
if (isdigit(word[0])) {
num = atoi( word );
} else {
return pstrcat( p, "bad expires code, numeric value expected <num> '",
word, "'", NULL);
};
/* <type>
*/
word = getword_conf( p, &code );
if ( word[0] ) {
/* do nothing */
} else {
return 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 pstrcat( p, "bad expires code, unrecognised <type>",
"'", word, "'", NULL);
};
modifier = modifier + factor * num;
/* next <num>
*/
word = getword_conf( p, &code );
};
ap_snprintf(foo, sizeof(foo), "%c%d", base, modifier );
*real_code = pstrdup( p, foo );
return NULL;
}
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 ) {
table_set (dir_config->expiresbytype, mime, real_code);
return NULL;
};
return pstrcat( cmd->pool,
"'ExpiresByType ", mime, " ", code, "': ", response, NULL );
}
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 = pstrdup( cmd->pool, real_code );
return NULL;
};
return pstrcat( cmd->pool,
"'ExpiresDefault ", code, "': ", response, NULL );
}
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 }
};
void *merge_expires_dir_configs (pool *p, void *basev, void *addv)
{
expires_dir_config *new= (expires_dir_config*)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 = overlay_tables (p, add->expiresbytype,
base->expiresbytype);
return new;
}
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 (is_HTTP_ERROR(r->status)) /* Don't add Expires headers to errors */
return DECLINED;
if (r->main != NULL) /* Say no to subrequests */
return DECLINED;
if ( r->finfo.st_mode == 0 ) /* no file ? shame. */
return DECLINED;
conf = (expires_dir_config *)get_module_config(r->per_dir_config, &expires_module);
if ( conf == NULL ) {
log_reason ("internal error in expires_module; add_expires(), conf == NULL", r->filename, r);
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 *) table_get( conf->expiresbytype, 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':
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 = time( NULL );
additional = atoi( &code[1] );
break;
default:
/* expecting the add_* routines to be case-hardened this
* is just a reminder that module is beta
*/
log_reason ("internal error in expires_module; bad expires code", r->filename, r);
return SERVER_ERROR;
};
expires = base + additional;
ap_snprintf(age, sizeof(age), "max-age=%d", (int)expires - (int)time(NULL));
table_set( r->headers_out, "Cache-Control", age);
tzset(); /* redundant? called implicitly by localtime, at least
* under FreeBSD
*/
table_set( r->headers_out, "Expires", 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 */
};
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.