75067b1beba1380cde707c30e7fc050d86f6927fKarl Luc

#include "apr.h"

#include "apr_strings.h"

#include "apr_lib.h"

#define APR_WANT_STRFUNC

#include "apr_want.h"

#include "ap_config.h"

#include "httpd.h"

#include "http_config.h"

#include "http_log.h"

#include "http_request.h"

typedef struct {

int active;

char *expiresdefault;

apr_table_t *expiresbytype;

} expires_dir_config;

#define DIR_CMD_PERMS OR_INDEXES

#define ACTIVE_ON 1

#define ACTIVE_OFF 0

#define ACTIVE_DONTCARE 2

module AP_MODULE_DECLARE_DATA expires_module;

static void *create_dir_expires_config(apr_pool_t *p, char *dummy)

{

expires_dir_config *new =

(expires_dir_config *) apr_pcalloc(p, sizeof(expires_dir_config));

new->active = ACTIVE_DONTCARE;

new->expiresdefault = "";

new->expiresbytype = apr_table_make(p, 4);

return (void *) new;

}

static const char *set_expiresactive(cmd_parms *cmd, void *in_dir_config, int arg)

{

expires_dir_config *dir_config = in_dir_config;

/* if we're here at all it's because someone explicitly

dir_config->active = ACTIVE_ON;

if (arg == 0) {

dir_config->active = ACTIVE_OFF;

};

return NULL;

}

static char *check_code(apr_pool_t *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 apr_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 (apr_isdigit(word[0])) {

num = atoi(word);

}

else {

return apr_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 apr_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 apr_pstrcat(p, "bad expires code, unrecognised <type>",

"'", word, "'", NULL);

};

modifier = modifier + factor * num;

/* next <num>

word = ap_getword_conf(p, &code);

};

*real_code = apr_psprintf(p, "%c%d", base, modifier);

return NULL;

}

static const char *set_expiresbytype(cmd_parms *cmd, void *in_dir_config,

const char *mime, const char *code)

{

expires_dir_config *dir_config = in_dir_config;

char *response, *real_code;

if ((response = check_code(cmd->pool, code, &real_code)) == NULL) {

apr_table_setn(dir_config->expiresbytype, mime, real_code);

return NULL;

};

return apr_pstrcat(cmd->pool,

"'ExpiresByType ", mime, " ", code, "': ", response, NULL);

}

static const char *set_expiresdefault(cmd_parms *cmd, void *in_dir_config,

const char *code)

{

expires_dir_config * dir_config = in_dir_config;

char *response, *real_code;

if ((response = check_code(cmd->pool, code, &real_code)) == NULL) {

dir_config->expiresdefault = real_code;

return NULL;

};

return apr_pstrcat(cmd->pool,

"'ExpiresDefault ", code, "': ", response, NULL);

}

static const command_rec expires_cmds[] =

{

AP_INIT_FLAG("ExpiresActive", set_expiresactive, NULL, DIR_CMD_PERMS,

"Limited to 'on' or 'off'"),

AP_INIT_TAKE2("ExpiresBytype", set_expiresbytype, NULL, DIR_CMD_PERMS,

"a MIME type followed by an expiry date code"),

AP_INIT_TAKE1("ExpiresDefault", set_expiresdefault, NULL, DIR_CMD_PERMS,

"an expiry date code"),

{NULL}

};

static void *merge_expires_dir_configs(apr_pool_t *p, void *basev, void *addv)

{

expires_dir_config *new = (expires_dir_config *) apr_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] != '\0') {

new->expiresdefault = add->expiresdefault;

}

else {

new->expiresdefault = base->expiresdefault;

}

new->expiresbytype = apr_table_overlay(p, add->expiresbytype,

base->expiresbytype);

return new;

}

static int add_expires(request_rec *r)

{

expires_dir_config *conf;

char *code;

apr_time_t base;

apr_time_t additional;

apr_time_t expires;

char *timestr;

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, 0, r,

"internal error: %s", r->filename);

return HTTP_INTERNAL_SERVER_ERROR;

};

if (conf->active != ACTIVE_ON)

return DECLINED;

/* we perhaps could use the default_type(r) in its place but that

if (r->content_type == NULL)

code = NULL;

else

code = (char *) apr_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.filetype == 0) {

/* file doesn't exist on disk, so we can't do anything based on

return DECLINED;

}

base = r->finfo.mtime;

additional = atoi(&code[1]);

break;

case 'A':

/* there's been some discussion and it's possible that

base = r->request_time;

additional = atoi(&code[1]);

break;

default:

/* expecting the add_* routines to be case-hardened this

ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, r,

"internal error: bad expires code: %s", r->filename);

return HTTP_INTERNAL_SERVER_ERROR;

};

expires = base + additional;

apr_table_mergen(r->headers_out, "Cache-Control",

apr_psprintf(r->pool, "max-age=%qd",

(expires - r->request_time)

/ APR_USEC_PER_SEC));

timestr = apr_palloc(r->pool, APR_RFC822_DATE_LEN);

apr_rfc822_date(timestr, expires);

apr_table_setn(r->headers_out, "Expires", timestr);

return OK;

}

static void register_hooks(apr_pool_t *p)

{

ap_hook_fixups(add_expires,NULL,NULL,APR_HOOK_MIDDLE);

}

module AP_MODULE_DECLARE_DATA expires_module =

{

STANDARD20_MODULE_STUFF,

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 apr_table_t */

register_hooks /* register hooks */

};