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

   1 /* Copyright 1999-2005 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_byterange_filter_handle;
  43
  44 static const char *set_keep_alive_timeout(cmd_parms *cmd, void *dummy,
  45                                           const char *arg)
  46 {
  47     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  48     if (err != NULL) {
  49         return err;
  50     }
  51
  52     cmd->server->keep_alive_timeout = apr_time_from_sec(atoi(arg));
  53     return NULL;
  54 }
  55
  56 static const char *set_keep_alive(cmd_parms *cmd, void *dummy,
  57                                   const char *arg)
  58 {
  59     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  60     if (err != NULL) {
  61         return err;
  62     }
  63
  64     /* We've changed it to On/Off, but used to use numbers
  65      * so we accept anything but "Off" or "0" as "On"
  66      */
  67     if (!strcasecmp(arg, "off") || !strcmp(arg, "0")) {
  68         cmd->server->keep_alive = 0;
  69     }
  70     else {
  71         cmd->server->keep_alive = 1;
  72     }
  73     return NULL;
  74 }
  75
  76 static const char *set_keep_alive_max(cmd_parms *cmd, void *dummy,
  77                                       const char *arg)
  78 {
  79     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  80     if (err != NULL) {
  81         return err;
  82     }
  83
  84     cmd->server->keep_alive_max = atoi(arg);
  85     return NULL;
  86 }
  87
  88 static const command_rec http_cmds[] = {
  89     AP_INIT_TAKE1("KeepAliveTimeout", set_keep_alive_timeout, NULL, RSRC_CONF,
  90                   "Keep-Alive timeout duration (sec)"),
  91     AP_INIT_TAKE1("MaxKeepAliveRequests", set_keep_alive_max, NULL, RSRC_CONF,
  92                   "Maximum number of Keep-Alive requests per connection, "
  93                   "or 0 for infinite"),
  94     AP_INIT_TAKE1("KeepAlive", set_keep_alive, NULL, RSRC_CONF,
  95                   "Whether persistent connections should be On or Off"),
  96     { NULL }
  97 };
  98
  99 static const char *http_scheme(const request_rec *r)
 100 {
 101     return "http";
 102 }
 103
 104 static apr_port_t http_port(const request_rec *r)
 105 {
 106     return DEFAULT_HTTP_PORT;
 107 }
 108
 109 static int ap_process_http_async_connection(conn_rec *c)
 110 {
 111     request_rec *r;
 112     conn_state_t *cs = c->cs;
 113
 114     AP_DEBUG_ASSERT(cs->state == CONN_STATE_READ_REQUEST_LINE);
 115
 116     while (cs->state == CONN_STATE_READ_REQUEST_LINE) {
 117         ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 118
 119         if ((r = ap_read_request(c))) {
 120
 121             c->keepalive = AP_CONN_UNKNOWN;
 122             /* process the request if it was read without error */
 123
 124             ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 125             if (r->status == HTTP_OK) {
 126                 cs->state = CONN_STATE_HANDLER;
 127                 ap_process_async_request(r);
 128                 /* After the call to ap_process_request, the
 129                  * request pool may have been deleted.  We set
 130                  * r=NULL here to ensure that any dereference
 131                  * of r that might be added later in this function
 132                  * will result in a segfault immediately instead
 133                  * of nondeterministic failures later.
 134                  */
 135                 r = NULL;
 136             }
 137
 138             if (cs->state != CONN_STATE_WRITE_COMPLETION) {
 139                 /* Something went wrong; close the connection */
 140                 cs->state = CONN_STATE_LINGER;
 141             }
 142         }
 143         else {   /* ap_read_request failed - client may have closed */
 144             cs->state = CONN_STATE_LINGER;
 145         }
 146     }
 147
 148     return OK;
 149 }
 150
 151 static int ap_process_http_connection(conn_rec *c)
 152 {
 153     request_rec *r;
 154     conn_state_t *cs = c->cs;
 155     apr_socket_t *csd = NULL;
 156
 157     /*
 158      * Read and process each request found on our connection
 159      * until no requests are left or we decide to close.
 160      */
 161
 162     ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 163     while ((r = ap_read_request(c)) != NULL) {
 164
 165         c->keepalive = AP_CONN_UNKNOWN;
 166         /* process the request if it was read without error */
 167
 168         ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 169         if (r->status == HTTP_OK) {
 170             cs->state = CONN_STATE_HANDLER;
 171             ap_process_request(r);
 172             /* After the call to ap_process_request, the
 173              * request pool will have been deleted.  We set
 174              * r=NULL here to ensure that any dereference
 175              * of r that might be added later in this function
 176              * will result in a segfault immediately instead
 177              * of nondeterministic failures later.
 178              */
 179             r = NULL;
 180         }
 181
 182         if (c->keepalive != AP_CONN_KEEPALIVE || c->aborted)
 183             break;
 184
 185         ap_update_child_status(c->sbh, SERVER_BUSY_KEEPALIVE, NULL);
 186
 187         if (ap_graceful_stop_signalled())
 188             break;
 189
 190         if (!csd) {
 191             csd = ap_get_module_config(c->conn_config, &core_module);
 192         }
 193         apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 1);
 194         apr_socket_timeout_set(csd, c->base_server->keep_alive_timeout);
 195         /* Go straight to select() to wait for the next request */
 196     }
 197
 198     return OK;
 199 }
 200
 201 static int http_create_request(request_rec *r)
 202 {
 203     if (!r->main && !r->prev) {
 204         ap_add_output_filter_handle(ap_byterange_filter_handle,
 205                                     NULL, r, r->connection);
 206         ap_add_output_filter_handle(ap_content_length_filter_handle,
 207                                     NULL, r, r->connection);
 208         ap_add_output_filter_handle(ap_http_header_filter_handle,
 209                                     NULL, r, r->connection);
 210     }
 211
 212     return OK;
 213 }
 214
 215 static void register_hooks(apr_pool_t *p)
 216 {
 217     /**
 218      * If we ae using an MPM That Supports Async Connections,
 219      * use a different processing function
 220      */
 221     int async_mpm = 0;
 222     if (ap_mpm_query(AP_MPMQ_IS_ASYNC, &async_mpm) == APR_SUCCESS
 223         && async_mpm == 1) {
 224         ap_hook_process_connection(ap_process_http_async_connection, NULL,
 225                                    NULL, APR_HOOK_REALLY_LAST);
 226     }
 227     else {
 228         ap_hook_process_connection(ap_process_http_connection, NULL, NULL,
 229                                    APR_HOOK_REALLY_LAST);
 230     }
 231
 232     ap_hook_map_to_storage(ap_send_http_trace,NULL,NULL,APR_HOOK_MIDDLE);
 233     ap_hook_http_scheme(http_scheme,NULL,NULL,APR_HOOK_REALLY_LAST);
 234     ap_hook_default_port(http_port,NULL,NULL,APR_HOOK_REALLY_LAST);
 235     ap_hook_create_request(http_create_request, NULL, NULL, APR_HOOK_REALLY_LAST);
 236     ap_http_input_filter_handle =
 237         ap_register_input_filter("HTTP_IN", ap_http_filter,
 238                                  NULL, AP_FTYPE_PROTOCOL);
 239     ap_http_header_filter_handle =
 240         ap_register_output_filter("HTTP_HEADER", ap_http_header_filter,
 241                                   NULL, AP_FTYPE_PROTOCOL);
 242     ap_chunk_filter_handle =
 243         ap_register_output_filter("CHUNK", ap_http_chunk_filter,
 244                                   NULL, AP_FTYPE_TRANSCODE);
 245     ap_byterange_filter_handle =
 246         ap_register_output_filter("BYTERANGE", ap_byterange_filter,
 247                                   NULL, AP_FTYPE_PROTOCOL);
 248     ap_method_registry_init(p);
 249 }
 250
 251 module AP_MODULE_DECLARE_DATA http_module = {
 252     STANDARD20_MODULE_STUFF,
 253     NULL,                       /* create per-directory config structure */
 254     NULL,                       /* merge per-directory config structures */
 255     NULL,                       /* create per-server config structure */
 256     NULL,                       /* merge per-server config structures */
 257     http_cmds,                  /* command apr_table_t */
 258     register_hooks              /* register hooks */
 259 };