Идея модуля такова - но становится обработчиком */* запросов. Апач
вызывает этот хендлер только если не было никаких других обработок его,
т.е. имеем то, что нам надо - выдачу голого файла.
В этом случае модуль выдает X-Accel-Redirect без тела самого файла
(устанавливая Content-Length: 0)
Переданный X-Accel-Redirect состоит из двух частей - строки, принятой от
вронтенда в заголовке X-Accel-Internal и собственно URI.
Установка минимального размера запрашиваемого файла, начиная с
которого будут выдаваться редиректы
Контенты обоих директив: server config, virtual host, directory
Установка в апач, конечно же
/usr/local/apache/bin/apxs -c mod_aclr.c
/usr/local/apache/bin/apxs -i mod_aclr.so
И руками добавить
LoadModule aclr_module libexec/mod_aclr.so
AddModule mod_aclr.c
Буду признателен за любые замечания, как по алгоритму, так и по коду.
/* -------------------------------------------------------------------------- * * mod_aclr.c *
* Dmitriy MiksIr <miksir@xxxxxxxx> *
* *
* Description FIX IT *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License *
* as published by the Free Software Foundation; either version 2 *
* of the License, or (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the Free Software *
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.*
\* -------------------------------------------------------------------------- */
/*
$Id: mod_aclr.c,v 1.1 2005/12/23 14:05:06 cvs Exp $
*/
#include "httpd.h"
#include "http_config.h"
#include "http_request.h"
#include "http_protocol.h"
#include "http_core.h"
#include "http_main.h"
#include "http_log.h"
module aclr_module;
#define ACLR_VERSION "0.01"
#define ACLR_ENABLED 1
#define ACLR_DISABLED 0
#define UNSET -1
typedef struct {
int state;
long long fsize;
} aclr_dir_config;
/* ----------------------------------------- */
long long parse_bytes(const char *arg) {
long long ret;
int arglen = strlen(arg);
char last_char = arg[arglen - 1];
int i;
char arg1[256];
if (arglen >= 256) return(-1);
if(last_char == 'K' || last_char == 'k'
|| last_char == 'M' || last_char == 'm') {
arglen --;
}
snprintf(arg1,sizeof(arg1),"%s",arg);
for (i=0;i<arglen;i++) {
if(!isdigit(arg1[i])) return(-1);
}
if(last_char == 'K' || last_char == 'k')
return(atoll(arg1) * 1024);
if(last_char == 'M' || last_char == 'm')
return(atoll(arg1) * 1048576);
return(atoll(arg1));
}
/* ----------------------------------------- */
static int aclr_handler(request_rec *r)
{
long long filesize;
int rc;
const char *idhead;
char iredirect[1024];
aclr_dir_config *cfg = (aclr_dir_config
*)ap_get_module_config(r->per_dir_config, &aclr_module);
if(cfg->state != ACLR_ENABLED)
return(DECLINED);
if (idhead = ap_table_get(r->headers_in, "X-Accel-Internal")) {
if (strlen(idhead)+strlen(r->uri) >= 1024)
return(DECLINED);
snprintf(iredirect,sizeof(iredirect),"%s%s",idhead,r->uri);
} else {
return(DECLINED);
}
ap_table_set(r->headers_out, "X-ACLR-Version", ACLR_VERSION);
if ((rc = ap_discard_request_body(r)) != OK) {
return rc;
}
if (r->method_number != M_GET)
return(DECLINED);
if (r->finfo.st_mode == 0 || (r->path_info && *r->path_info))
return(DECLINED);
filesize = r->finfo.st_size;
if (cfg->fsize != UNSET && filesize < cfg->fsize)
return(DECLINED);
ap_table_set(r->headers_out, "X-Accel-Redirect", iredirect);
ap_update_mtime(r, r->finfo.st_mtime);
if (rc = ap_set_content_length(r, 0))
return rc;
ap_send_http_header(r);
return OK;
}
/* ------------------------------------------ */
static void *aclr_create_dir_config(pool *p, char *path) {
aclr_dir_config *cfg = (aclr_dir_config *)ap_palloc(p,
sizeof(aclr_dir_config));
cfg->state = UNSET;
cfg->fsize = UNSET;
return( (void *)cfg );
}
/* ------------------------------------------ */
static const char *aclr_cmd_state(cmd_parms *parms, void *mconfig, int flag) {
aclr_dir_config *cfg = (aclr_dir_config *)mconfig;
cfg->state = (flag ? ACLR_ENABLED : ACLR_DISABLED);
return(NULL);
}
static const char *aclr_cmd_size(cmd_parms *parms, void *mconfig, const char
*arg) {
aclr_dir_config *cfg = (aclr_dir_config *)mconfig;
long long bytes = parse_bytes(arg);
if (bytes >= 0) {
cfg->fsize = bytes;
} else {
cfg->fsize = UNSET;
ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, parms->server,
"Argument %s of AccelRedirectSize is not number", arg);
}
return(NULL);
}
static const command_rec aclr_cmds[] = {
{ "AccelRedirectSet", aclr_cmd_state, NULL, ACCESS_CONF | RSRC_CONF, FLAG,
"turn X-Accel-Redirect support On or Off (default Off)" },
{ "AccelRedirectSize", aclr_cmd_size, NULL, ACCESS_CONF | RSRC_CONF, TAKE1,
"minimum size of file for redirect in bytes" },
{ NULL }
};
/* ------------------------------------------- */
static const handler_rec aclr_handlers[] = {
{ "*/*", aclr_handler },
{ NULL }
};
module MODULE_VAR_EXPORT aclr_module = {
STANDARD_MODULE_STUFF,
NULL, /* module initializer */
aclr_create_dir_config, /* create per-dir config structures */
NULL, /* merge per-dir config structures */
NULL, /* create per-server config structures */
NULL, /* merge per-server config structures */
aclr_cmds, /* table of config file commands */
aclr_handlers, /* [#8] MIME-typed-dispatched handlers */
NULL, /* [#1] URI to filename translation */
NULL, /* [#4] validate user id from request */
NULL, /* [#5] check if the user is ok _here_ */
NULL, /* [#3] check access by host address */
NULL, /* [#6] determine MIME type */
NULL, /* [#7] pre-run fixups */
NULL, /* [#9] log a transaction */
NULL, /* [#2] header parser */
NULL, /* child_init */
NULL, /* child_exit */
NULL /* [#0] post read-request */
};
