modules/test/mod_dialup.c - httpd - Git at Google

 /* 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.
  */


 #include "httpd.h"
 #include "http_core.h"

 #include "util_filter.h"
 #include "http_log.h"
 #include "http_config.h"
 #include "http_request.h"
 #include "http_protocol.h"


 #include "ap_mpm.h"

 module AP_MODULE_DECLARE_DATA dialup_module;

 typedef struct dialup_dcfg_t {
     apr_size_t bytes_per_second;
 } dialup_dcfg_t;

 typedef struct dialup_baton_t {
     apr_size_t bytes_per_second;
     request_rec *r;
     apr_file_t *fd;
     apr_bucket_brigade *bb;
     apr_bucket_brigade *tmpbb;
 } dialup_baton_t;

 static int
 dialup_send_pulse(dialup_baton_t *db)
 {
     int status;
     apr_off_t len = 0;
     apr_size_t bytes_sent = 0;

     while (!APR_BRIGADE_EMPTY(db->bb) && bytes_sent < db->bytes_per_second) {
         apr_bucket *e;

         if (db->r->connection->aborted) {
             return HTTP_INTERNAL_SERVER_ERROR;
         }

         status = apr_brigade_partition(db->bb, db->bytes_per_second, &e);

         if (status != APR_SUCCESS && status != APR_INCOMPLETE) {
             /* XXXXXX: Log me. */
             return HTTP_INTERNAL_SERVER_ERROR;
         }

         if (e != APR_BRIGADE_SENTINEL(db->bb)) {
             apr_bucket *f;
             apr_bucket *b = APR_BUCKET_PREV(e);
             f = APR_RING_FIRST(&db->bb->list);
             APR_RING_UNSPLICE(f, b, link);
             APR_RING_SPLICE_HEAD(&db->tmpbb->list, f, b, apr_bucket, link);
         }
         else {
             APR_BRIGADE_CONCAT(db->tmpbb, db->bb);
         }

         e = apr_bucket_flush_create(db->r->connection->bucket_alloc);

         APR_BRIGADE_INSERT_TAIL(db->tmpbb, e);

         apr_brigade_length(db->tmpbb, 1, &len);
         bytes_sent += len;
         status = ap_pass_brigade(db->r->output_filters, db->tmpbb);

         apr_brigade_cleanup(db->tmpbb);

         if (status != APR_SUCCESS) {
             ap_log_rerror(APLOG_MARK, APLOG_ERR, status, db->r, APLOGNO(01867)
                           "dialup: pulse: ap_pass_brigade failed:");
             return AP_FILTER_ERROR;
         }
     }

     if (APR_BRIGADE_EMPTY(db->bb)) {
         return DONE;
     }
     else {
         return SUSPENDED;
     }
 }

 static void
 dialup_callback(void *baton)
 {
     int status;
     dialup_baton_t *db = (dialup_baton_t *)baton;
     conn_rec *c = db->r->connection;

     apr_thread_mutex_lock(db->r->invoke_mtx);

     status = dialup_send_pulse(db);

     if (status == SUSPENDED) {
         ap_mpm_register_timed_callback(apr_time_from_sec(1), dialup_callback, baton);
     }
     else if (status == DONE) {
         apr_thread_mutex_unlock(db->r->invoke_mtx);
         ap_finalize_request_protocol(db->r);
         ap_process_request_after_handler(db->r);
         return;
     }
     else {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, db->r, APLOGNO(01868)
                       "dialup: pulse returned: %d", status);
         db->r->status = HTTP_OK;
         ap_die(status, db->r);
     }

     apr_thread_mutex_unlock(db->r->invoke_mtx);

     ap_mpm_resume_suspended(c);
 }

 static int
 dialup_handler(request_rec *r)
 {
     int status;
     apr_status_t rv;
     dialup_dcfg_t *dcfg;
     core_dir_config *ccfg;
     apr_file_t *fd;
     dialup_baton_t *db;
     apr_bucket *e;
     int mpm_can_suspend = 0;

     /* See core.c, default handler for all of the cases we just decline. */
     if (r->method_number != M_GET ||
         r->finfo.filetype == APR_NOFILE ||
         r->finfo.filetype == APR_DIR) {
         return DECLINED;
     }

     rv = ap_mpm_query(AP_MPMQ_CAN_SUSPEND, &mpm_can_suspend);
     if (!mpm_can_suspend) {
         ap_log_rerror (APLOG_MARK, APLOG_NOTICE, rv, r, APLOGNO(02637)
                 "dialup: MPM doesn't support suspending");
         return DECLINED;
     }

     dcfg = ap_get_module_config(r->per_dir_config,
                                 &dialup_module);

     if (dcfg->bytes_per_second == 0) {
         return DECLINED;
     }

     ccfg = ap_get_core_module_config(r->per_dir_config);


     rv = apr_file_open(&fd, r->filename, APR_READ | APR_BINARY
 #if APR_HAS_SENDFILE
                            | AP_SENDFILE_ENABLED(ccfg->enable_sendfile)
 #endif
                        , 0, r->pool);

     if (rv) {
         return DECLINED;
     }

     /* copied from default handler: */
     ap_update_mtime(r, r->finfo.mtime);
     ap_set_last_modified(r);
     ap_set_etag(r);
     ap_set_accept_ranges(r);
     ap_set_content_length(r, r->finfo.size);

     status = ap_meets_conditions(r);
     if (status != OK) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01869)
                       "dialup: declined, meets conditions, good luck core handler");
         return DECLINED;
     }

     db = apr_palloc(r->pool, sizeof(dialup_baton_t));

     db->bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
     db->tmpbb = apr_brigade_create(r->pool, r->connection->bucket_alloc);

     e = apr_brigade_insert_file(db->bb, fd, 0, r->finfo.size, r->pool);

 #if APR_HAS_MMAP
     if (ccfg->enable_mmap == ENABLE_MMAP_OFF) {
         apr_bucket_file_enable_mmap(e, 0);
     }
 #endif


     db->bytes_per_second = dcfg->bytes_per_second;
     db->r = r;
     db->fd = fd;

     e = apr_bucket_eos_create(r->connection->bucket_alloc);

     APR_BRIGADE_INSERT_TAIL(db->bb, e);

     status = dialup_send_pulse(db);
     if (status != SUSPENDED && status != DONE) {
         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01870)
                       "dialup: failed, send pulse");
         return status;
     }

     ap_mpm_register_timed_callback(apr_time_from_sec(1), dialup_callback, db);

     return SUSPENDED;
 }


 #ifndef APR_HOOK_ALMOST_LAST
 #define APR_HOOK_ALMOST_LAST (APR_HOOK_REALLY_LAST - 1)
 #endif

 static void
 dialup_register_hooks(apr_pool_t *p)
 {
     ap_hook_handler(dialup_handler, NULL, NULL, APR_HOOK_ALMOST_LAST);
 }

 typedef struct modem_speed_t {
     const char *name;
     apr_size_t bytes_per_second;
 } modem_speed_t;

 #ifndef BITRATE_TO_BYTES
 #define BITRATE_TO_BYTES(x) ((1000 * x)/8)
 #endif

 static const modem_speed_t modem_bitrates[] =
 {
     {"V.21",    BITRATE_TO_BYTES(0.1)},
     {"V.26bis", BITRATE_TO_BYTES(2.4)},
     {"V.32",    BITRATE_TO_BYTES(9.6)},
     {"V.34",    BITRATE_TO_BYTES(28.8)},
     {"V.92",    BITRATE_TO_BYTES(56.0)},
     {"i-was-rich-and-got-a-leased-line", BITRATE_TO_BYTES(1500)},
     {NULL, 0}
 };

 static const char *
 cmd_modem_standard(cmd_parms *cmd,
              void *dconf,
              const char *input)
 {
     const modem_speed_t *standard;
     int i = 0;
     dialup_dcfg_t *dcfg = (dialup_dcfg_t*)dconf;

     dcfg->bytes_per_second = 0;

     while (modem_bitrates[i].name != NULL) {
         standard = &modem_bitrates[i];
         if (strcasecmp(standard->name, input) == 0) {
             dcfg->bytes_per_second = standard->bytes_per_second;
             break;
         }
         i++;
     }

     if (dcfg->bytes_per_second == 0) {
         return "mod_diaulup: Unkonwn Modem Standard specified.";
     }

     return NULL;
 }

 static void *
 dialup_dcfg_create(apr_pool_t *p, char *dummy)
 {
     dialup_dcfg_t *cfg = apr_palloc(p, sizeof(dialup_dcfg_t));

     cfg->bytes_per_second = 0;

     return cfg;
 }


 static const command_rec dialup_cmds[] =
 {
     AP_INIT_TAKE1("ModemStandard", cmd_modem_standard, NULL, ACCESS_CONF,
                   "Modem Standard to.. simulate. "
                   "Must be one of: 'V.21', 'V.26bis', 'V.32', 'V.34', or 'V.92'"),
     {NULL}
 };

 AP_DECLARE_MODULE(dialup) =
 {
     STANDARD20_MODULE_STUFF,
     dialup_dcfg_create,
     NULL,
     NULL,
     NULL,
     dialup_cmds,
     dialup_register_hooks
 };
	/* 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.
	*/



	#include "httpd.h"
	#include "http_core.h"

	#include "util_filter.h"
	#include "http_log.h"
	#include "http_config.h"
	#include "http_request.h"
	#include "http_protocol.h"



	#include "ap_mpm.h"

	module AP_MODULE_DECLARE_DATA dialup_module;

	typedef struct dialup_dcfg_t {
	apr_size_t bytes_per_second;
	} dialup_dcfg_t;

	typedef struct dialup_baton_t {
	apr_size_t bytes_per_second;
	request_rec *r;
	apr_file_t *fd;
	apr_bucket_brigade *bb;
	apr_bucket_brigade *tmpbb;
	} dialup_baton_t;

	static int
	dialup_send_pulse(dialup_baton_t *db)
	{
	int status;
	apr_off_t len = 0;
	apr_size_t bytes_sent = 0;

	while (!APR_BRIGADE_EMPTY(db->bb) && bytes_sent < db->bytes_per_second) {
	apr_bucket *e;

	if (db->r->connection->aborted) {
	return HTTP_INTERNAL_SERVER_ERROR;
	}

	status = apr_brigade_partition(db->bb, db->bytes_per_second, &e);

	if (status != APR_SUCCESS && status != APR_INCOMPLETE) {
	/* XXXXXX: Log me. */
	return HTTP_INTERNAL_SERVER_ERROR;
	}

	if (e != APR_BRIGADE_SENTINEL(db->bb)) {
	apr_bucket *f;
	apr_bucket *b = APR_BUCKET_PREV(e);
	f = APR_RING_FIRST(&db->bb->list);
	APR_RING_UNSPLICE(f, b, link);
	APR_RING_SPLICE_HEAD(&db->tmpbb->list, f, b, apr_bucket, link);
	}
	else {
	APR_BRIGADE_CONCAT(db->tmpbb, db->bb);
	}

	e = apr_bucket_flush_create(db->r->connection->bucket_alloc);

	APR_BRIGADE_INSERT_TAIL(db->tmpbb, e);

	apr_brigade_length(db->tmpbb, 1, &len);
	bytes_sent += len;
	status = ap_pass_brigade(db->r->output_filters, db->tmpbb);

	apr_brigade_cleanup(db->tmpbb);

	if (status != APR_SUCCESS) {
	ap_log_rerror(APLOG_MARK, APLOG_ERR, status, db->r, APLOGNO(01867)
	"dialup: pulse: ap_pass_brigade failed:");
	return AP_FILTER_ERROR;
	}
	}

	if (APR_BRIGADE_EMPTY(db->bb)) {
	return DONE;
	}
	else {
	return SUSPENDED;
	}
	}

	static void
	dialup_callback(void *baton)
	{
	int status;
	dialup_baton_t db = (dialup_baton_t )baton;
	conn_rec *c = db->r->connection;

	apr_thread_mutex_lock(db->r->invoke_mtx);

	status = dialup_send_pulse(db);

	if (status == SUSPENDED) {
	ap_mpm_register_timed_callback(apr_time_from_sec(1), dialup_callback, baton);
	}
	else if (status == DONE) {
	apr_thread_mutex_unlock(db->r->invoke_mtx);
	ap_finalize_request_protocol(db->r);
	ap_process_request_after_handler(db->r);
	return;
	}
	else {
	ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, db->r, APLOGNO(01868)
	"dialup: pulse returned: %d", status);
	db->r->status = HTTP_OK;
	ap_die(status, db->r);
	}

	apr_thread_mutex_unlock(db->r->invoke_mtx);

	ap_mpm_resume_suspended(c);
	}

	static int
	dialup_handler(request_rec *r)
	{
	int status;
	apr_status_t rv;
	dialup_dcfg_t *dcfg;
	core_dir_config *ccfg;
	apr_file_t *fd;
	dialup_baton_t *db;
	apr_bucket *e;
	int mpm_can_suspend = 0;

	/* See core.c, default handler for all of the cases we just decline. */
	if (r->method_number != M_GET \|\|
	r->finfo.filetype == APR_NOFILE \|\|
	r->finfo.filetype == APR_DIR) {
	return DECLINED;
	}

	rv = ap_mpm_query(AP_MPMQ_CAN_SUSPEND, &mpm_can_suspend);
	if (!mpm_can_suspend) {
	ap_log_rerror (APLOG_MARK, APLOG_NOTICE, rv, r, APLOGNO(02637)
	"dialup: MPM doesn't support suspending");
	return DECLINED;
	}

	dcfg = ap_get_module_config(r->per_dir_config,
	&dialup_module);

	if (dcfg->bytes_per_second == 0) {
	return DECLINED;
	}

	ccfg = ap_get_core_module_config(r->per_dir_config);


	rv = apr_file_open(&fd, r->filename, APR_READ \| APR_BINARY
	#if APR_HAS_SENDFILE
	\| AP_SENDFILE_ENABLED(ccfg->enable_sendfile)
	#endif
	, 0, r->pool);

	if (rv) {
	return DECLINED;
	}

	/* copied from default handler: */
	ap_update_mtime(r, r->finfo.mtime);
	ap_set_last_modified(r);
	ap_set_etag(r);
	ap_set_accept_ranges(r);
	ap_set_content_length(r, r->finfo.size);

	status = ap_meets_conditions(r);
	if (status != OK) {
	ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01869)
	"dialup: declined, meets conditions, good luck core handler");
	return DECLINED;
	}

	db = apr_palloc(r->pool, sizeof(dialup_baton_t));

	db->bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
	db->tmpbb = apr_brigade_create(r->pool, r->connection->bucket_alloc);

	e = apr_brigade_insert_file(db->bb, fd, 0, r->finfo.size, r->pool);

	#if APR_HAS_MMAP
	if (ccfg->enable_mmap == ENABLE_MMAP_OFF) {
	apr_bucket_file_enable_mmap(e, 0);
	}
	#endif


	db->bytes_per_second = dcfg->bytes_per_second;
	db->r = r;
	db->fd = fd;

	e = apr_bucket_eos_create(r->connection->bucket_alloc);

	APR_BRIGADE_INSERT_TAIL(db->bb, e);

	status = dialup_send_pulse(db);
	if (status != SUSPENDED && status != DONE) {
	ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01870)
	"dialup: failed, send pulse");
	return status;
	}

	ap_mpm_register_timed_callback(apr_time_from_sec(1), dialup_callback, db);

	return SUSPENDED;
	}



	#ifndef APR_HOOK_ALMOST_LAST
	#define APR_HOOK_ALMOST_LAST (APR_HOOK_REALLY_LAST - 1)
	#endif

	static void
	dialup_register_hooks(apr_pool_t *p)
	{
	ap_hook_handler(dialup_handler, NULL, NULL, APR_HOOK_ALMOST_LAST);
	}

	typedef struct modem_speed_t {
	const char *name;
	apr_size_t bytes_per_second;
	} modem_speed_t;

	#ifndef BITRATE_TO_BYTES
	#define BITRATE_TO_BYTES(x) ((1000 * x)/8)
	#endif

	static const modem_speed_t modem_bitrates[] =
	{
	{"V.21", BITRATE_TO_BYTES(0.1)},
	{"V.26bis", BITRATE_TO_BYTES(2.4)},
	{"V.32", BITRATE_TO_BYTES(9.6)},
	{"V.34", BITRATE_TO_BYTES(28.8)},
	{"V.92", BITRATE_TO_BYTES(56.0)},
	{"i-was-rich-and-got-a-leased-line", BITRATE_TO_BYTES(1500)},
	{NULL, 0}
	};

	static const char *
	cmd_modem_standard(cmd_parms *cmd,
	void *dconf,
	const char *input)
	{
	const modem_speed_t *standard;
	int i = 0;
	dialup_dcfg_t dcfg = (dialup_dcfg_t)dconf;

	dcfg->bytes_per_second = 0;

	while (modem_bitrates[i].name != NULL) {
	standard = &modem_bitrates[i];
	if (strcasecmp(standard->name, input) == 0) {
	dcfg->bytes_per_second = standard->bytes_per_second;
	break;
	}
	i++;
	}

	if (dcfg->bytes_per_second == 0) {
	return "mod_diaulup: Unkonwn Modem Standard specified.";
	}

	return NULL;
	}

	static void *
	dialup_dcfg_create(apr_pool_t p, char dummy)
	{
	dialup_dcfg_t *cfg = apr_palloc(p, sizeof(dialup_dcfg_t));

	cfg->bytes_per_second = 0;

	return cfg;
	}


	static const command_rec dialup_cmds[] =
	{
	AP_INIT_TAKE1("ModemStandard", cmd_modem_standard, NULL, ACCESS_CONF,
	"Modem Standard to.. simulate. "
	"Must be one of: 'V.21', 'V.26bis', 'V.32', 'V.34', or 'V.92'"),
	{NULL}
	};

	AP_DECLARE_MODULE(dialup) =
	{
	STANDARD20_MODULE_STUFF,
	dialup_dcfg_create,
	NULL,
	NULL,
	NULL,
	dialup_cmds,
	dialup_register_hooks
	};