granicus.if.org Git - apache/blob - modules/http/http_core.c

   1 /* Copyright 1999-2006 The Apache Software Foundation or its licensors, as
   2  * applicable.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "apr_strings.h"
  18 #include "apr_thread_proc.h"    /* for RLIMIT stuff */
  19
  20 #define APR_WANT_STRFUNC
  21 #include "apr_want.h"
  22
  23 #define CORE_PRIVATE
  24 #include "httpd.h"
  25 #include "http_config.h"
  26 #include "http_connection.h"
  27 #include "http_core.h"
  28 #include "http_protocol.h"   /* For index_of_response().  Grump. */
  29 #include "http_request.h"
  30
  31 #include "util_filter.h"
  32 #include "util_ebcdic.h"
  33 #include "ap_mpm.h"
  34 #include "scoreboard.h"
  35
  36 #include "mod_core.h"
  37
  38 /* Handles for core filters */
  39 AP_DECLARE_DATA ap_filter_rec_t *ap_http_input_filter_handle;
  40 AP_DECLARE_DATA ap_filter_rec_t *ap_http_header_filter_handle;
  41 AP_DECLARE_DATA ap_filter_rec_t *ap_chunk_filter_handle;
  42 AP_DECLARE_DATA ap_filter_rec_t *ap_http_outerror_filter_handle;
  43 AP_DECLARE_DATA ap_filter_rec_t *ap_byterange_filter_handle;
  44
  45 static const char *set_keep_alive_timeout(cmd_parms *cmd, void *dummy,
  46                                           const char *arg)
  47 {
  48     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  49     if (err != NULL) {
  50         return err;
  51     }
  52
  53     cmd->server->keep_alive_timeout = apr_time_from_sec(atoi(arg));
  54     return NULL;
  55 }
  56
  57 static const char *set_keep_alive(cmd_parms *cmd, void *dummy,
  58                                   const char *arg)
  59 {
  60     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  61     if (err != NULL) {
  62         return err;
  63     }
  64
  65     /* We've changed it to On/Off, but used to use numbers
  66      * so we accept anything but "Off" or "0" as "On"
  67      */
  68     if (!strcasecmp(arg, "off") || !strcmp(arg, "0")) {
  69         cmd->server->keep_alive = 0;
  70     }
  71     else {
  72         cmd->server->keep_alive = 1;
  73     }
  74     return NULL;
  75 }
  76
  77 static const char *set_keep_alive_max(cmd_parms *cmd, void *dummy,
  78                                       const char *arg)
  79 {
  80     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  81     if (err != NULL) {
  82         return err;
  83     }
  84
  85     cmd->server->keep_alive_max = atoi(arg);
  86     return NULL;
  87 }
  88
  89 static const command_rec http_cmds[] = {
  90     AP_INIT_TAKE1("KeepAliveTimeout", set_keep_alive_timeout, NULL, RSRC_CONF,
  91                   "Keep-Alive timeout duration (sec)"),
  92     AP_INIT_TAKE1("MaxKeepAliveRequests", set_keep_alive_max, NULL, RSRC_CONF,
  93                   "Maximum number of Keep-Alive requests per connection, "
  94                   "or 0 for infinite"),
  95     AP_INIT_TAKE1("KeepAlive", set_keep_alive, NULL, RSRC_CONF,
  96                   "Whether persistent connections should be On or Off"),
  97     { NULL }
  98 };
  99
 100 static const char *http_scheme(const request_rec *r)
 101 {
 102     return "http";
 103 }
 104
 105 static apr_port_t http_port(const request_rec *r)
 106 {
 107     return DEFAULT_HTTP_PORT;
 108 }
 109
 110 static int ap_process_http_async_connection(conn_rec *c)
 111 {
 112     request_rec *r;
 113     conn_state_t *cs = c->cs;
 114
 115     AP_DEBUG_ASSERT(cs->state == CONN_STATE_READ_REQUEST_LINE);
 116
 117     while (cs->state == CONN_STATE_READ_REQUEST_LINE) {
 118         ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 119
 120         if ((r = ap_read_request(c))) {
 121
 122             c->keepalive = AP_CONN_UNKNOWN;
 123             /* process the request if it was read without error */
 124
 125             ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 126             if (r->status == HTTP_OK) {
 127                 cs->state = CONN_STATE_HANDLER;
 128                 ap_process_async_request(r);
 129                 /* After the call to ap_process_request, the
 130                  * request pool may have been deleted.  We set
 131                  * r=NULL here to ensure that any dereference
 132                  * of r that might be added later in this function
 133                  * will result in a segfault immediately instead
 134                  * of nondeterministic failures later.
 135                  */
 136                 r = NULL;
 137             }
 138
 139             if (cs->state != CONN_STATE_WRITE_COMPLETION) {
 140                 /* Something went wrong; close the connection */
 141                 cs->state = CONN_STATE_LINGER;
 142             }
 143         }
 144         else {   /* ap_read_request failed - client may have closed */
 145             cs->state = CONN_STATE_LINGER;
 146         }
 147     }
 148
 149     return OK;
 150 }
 151
 152 static int ap_process_http_connection(conn_rec *c)
 153 {
 154     request_rec *r;
 155     conn_state_t *cs = c->cs;
 156     apr_socket_t *csd = NULL;
 157
 158     /*
 159      * Read and process each request found on our connection
 160      * until no requests are left or we decide to close.
 161      */
 162
 163     ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 164     while ((r = ap_read_request(c)) != NULL) {
 165
 166         c->keepalive = AP_CONN_UNKNOWN;
 167         /* process the request if it was read without error */
 168
 169         ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 170         if (r->status == HTTP_OK) {
 171             cs->state = CONN_STATE_HANDLER;
 172             ap_process_request(r);
 173             /* After the call to ap_process_request, the
 174              * request pool will have been deleted.  We set
 175              * r=NULL here to ensure that any dereference
 176              * of r that might be added later in this function
 177              * will result in a segfault immediately instead
 178              * of nondeterministic failures later.
 179              */
 180             r = NULL;
 181         }
 182
 183         if (c->keepalive != AP_CONN_KEEPALIVE || c->aborted)
 184             break;
 185
 186         ap_update_child_status(c->sbh, SERVER_BUSY_KEEPALIVE, NULL);
 187
 188         if (ap_graceful_stop_signalled())
 189             break;
 190
 191         if (!csd) {
 192             csd = ap_get_module_config(c->conn_config, &core_module);
 193         }
 194         apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 1);
 195         apr_socket_timeout_set(csd, c->base_server->keep_alive_timeout);
 196         /* Go straight to select() to wait for the next request */
 197     }
 198
 199     return OK;
 200 }
 201
 202 static int http_create_request(request_rec *r)
 203 {
 204     if (!r->main && !r->prev) {
 205         ap_add_output_filter_handle(ap_byterange_filter_handle,
 206                                     NULL, r, r->connection);
 207         ap_add_output_filter_handle(ap_content_length_filter_handle,
 208                                     NULL, r, r->connection);
 209         ap_add_output_filter_handle(ap_http_header_filter_handle,
 210                                     NULL, r, r->connection);
 211         ap_add_output_filter_handle(ap_http_outerror_filter_handle,
 212                                     NULL, r, r->connection);
 213     }
 214
 215     return OK;
 216 }
 217
 218 static void register_hooks(apr_pool_t *p)
 219 {
 220     /**
 221      * If we ae using an MPM That Supports Async Connections,
 222      * use a different processing function
 223      */
 224     int async_mpm = 0;
 225     if (ap_mpm_query(AP_MPMQ_IS_ASYNC, &async_mpm) == APR_SUCCESS
 226         && async_mpm == 1) {
 227         ap_hook_process_connection(ap_process_http_async_connection, NULL,
 228                                    NULL, APR_HOOK_REALLY_LAST);
 229     }
 230     else {
 231         ap_hook_process_connection(ap_process_http_connection, NULL, NULL,
 232                                    APR_HOOK_REALLY_LAST);
 233     }
 234
 235     ap_hook_map_to_storage(ap_send_http_trace,NULL,NULL,APR_HOOK_MIDDLE);
 236     ap_hook_http_scheme(http_scheme,NULL,NULL,APR_HOOK_REALLY_LAST);
 237     ap_hook_default_port(http_port,NULL,NULL,APR_HOOK_REALLY_LAST);
 238     ap_hook_create_request(http_create_request, NULL, NULL, APR_HOOK_REALLY_LAST);
 239     ap_http_input_filter_handle =
 240         ap_register_input_filter("HTTP_IN", ap_http_filter,
 241                                  NULL, AP_FTYPE_PROTOCOL);
 242     ap_http_header_filter_handle =
 243         ap_register_output_filter("HTTP_HEADER", ap_http_header_filter,
 244                                   NULL, AP_FTYPE_PROTOCOL);
 245     ap_chunk_filter_handle =
 246         ap_register_output_filter("CHUNK", ap_http_chunk_filter,
 247                                   NULL, AP_FTYPE_TRANSCODE);
 248     ap_http_outerror_filter_handle =
 249         ap_register_output_filter("HTTP_OUTERROR", ap_http_outerror_filter,
 250                                   NULL, AP_FTYPE_PROTOCOL);
 251     ap_byterange_filter_handle =
 252         ap_register_output_filter("BYTERANGE", ap_byterange_filter,
 253                                   NULL, AP_FTYPE_PROTOCOL);
 254     ap_method_registry_init(p);
 255 }
 256
 257 module AP_MODULE_DECLARE_DATA http_module = {
 258     STANDARD20_MODULE_STUFF,
 259     NULL,              /* create per-directory config structure */
 260     NULL,              /* merge per-directory config structures */
 261     NULL,              /* create per-server config structure */
 262     NULL,              /* merge per-server config structures */
 263     http_cmds,         /* command apr_table_t */
 264     register_hooks     /* register hooks */
 265 };