1 /* 2 * Copyright (c) 2000-2007 Niels Provos <provos (at) citi.umich.edu> 3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef EVENT2_HTTP_H_INCLUDED_ 28 #define EVENT2_HTTP_H_INCLUDED_ 29 30 /* For int types. */ 31 #include <event2/util.h> 32 #include <event2/visibility.h> 33 34 #ifdef __cplusplus 35 extern "C" { 36 #endif 37 38 /* In case we haven't included the right headers yet. */ 39 struct evbuffer; 40 struct event_base; 41 struct bufferevent; 42 struct evhttp_connection; 43 44 /** @file event2/http.h 45 * 46 * Basic support for HTTP serving. 47 * 48 * As Libevent is a library for dealing with event notification and most 49 * interesting applications are networked today, I have often found the 50 * need to write HTTP code. The following prototypes and definitions provide 51 * an application with a minimal interface for making HTTP requests and for 52 * creating a very simple HTTP server. 53 */ 54 55 /* Response codes */ 56 #define HTTP_OK 200 /**< request completed ok */ 57 #define HTTP_NOCONTENT 204 /**< request does not have content */ 58 #define HTTP_MOVEPERM 301 /**< the uri moved permanently */ 59 #define HTTP_MOVETEMP 302 /**< the uri moved temporarily */ 60 #define HTTP_NOTMODIFIED 304 /**< page was not modified from last */ 61 #define HTTP_BADREQUEST 400 /**< invalid http request was made */ 62 #define HTTP_NOTFOUND 404 /**< could not find content for uri */ 63 #define HTTP_BADMETHOD 405 /**< method not allowed for this uri */ 64 #define HTTP_ENTITYTOOLARGE 413 /**< */ 65 #define HTTP_EXPECTATIONFAILED 417 /**< we can't handle this expectation */ 66 #define HTTP_INTERNAL 500 /**< internal error */ 67 #define HTTP_NOTIMPLEMENTED 501 /**< not implemented */ 68 #define HTTP_SERVUNAVAIL 503 /**< the server is not available */ 69 70 struct evhttp; 71 struct evhttp_request; 72 struct evkeyvalq; 73 struct evhttp_bound_socket; 74 struct evconnlistener; 75 struct evdns_base; 76 77 /** 78 * Create a new HTTP server. 79 * 80 * @param base (optional) the event base to receive the HTTP events 81 * @return a pointer to a newly initialized evhttp server structure 82 * @see evhttp_free() 83 */ 84 EVENT2_EXPORT_SYMBOL 85 struct evhttp *evhttp_new(struct event_base *base); 86 87 /** 88 * Binds an HTTP server on the specified address and port. 89 * 90 * Can be called multiple times to bind the same http server 91 * to multiple different ports. 92 * 93 * @param http a pointer to an evhttp object 94 * @param address a string containing the IP address to listen(2) on 95 * @param port the port number to listen on 96 * @return 0 on success, -1 on failure. 97 * @see evhttp_accept_socket() 98 */ 99 EVENT2_EXPORT_SYMBOL 100 int evhttp_bind_socket(struct evhttp *http, const char *address, ev_uint16_t port); 101 102 /** 103 * Like evhttp_bind_socket(), but returns a handle for referencing the socket. 104 * 105 * The returned pointer is not valid after \a http is freed. 106 * 107 * @param http a pointer to an evhttp object 108 * @param address a string containing the IP address to listen(2) on 109 * @param port the port number to listen on 110 * @return Handle for the socket on success, NULL on failure. 111 * @see evhttp_bind_socket(), evhttp_del_accept_socket() 112 */ 113 EVENT2_EXPORT_SYMBOL 114 struct evhttp_bound_socket *evhttp_bind_socket_with_handle(struct evhttp *http, const char *address, ev_uint16_t port); 115 116 /** 117 * Makes an HTTP server accept connections on the specified socket. 118 * 119 * This may be useful to create a socket and then fork multiple instances 120 * of an http server, or when a socket has been communicated via file 121 * descriptor passing in situations where an http servers does not have 122 * permissions to bind to a low-numbered port. 123 * 124 * Can be called multiple times to have the http server listen to 125 * multiple different sockets. 126 * 127 * @param http a pointer to an evhttp object 128 * @param fd a socket fd that is ready for accepting connections 129 * @return 0 on success, -1 on failure. 130 * @see evhttp_bind_socket() 131 */ 132 EVENT2_EXPORT_SYMBOL 133 int evhttp_accept_socket(struct evhttp *http, evutil_socket_t fd); 134 135 /** 136 * Like evhttp_accept_socket(), but returns a handle for referencing the socket. 137 * 138 * The returned pointer is not valid after \a http is freed. 139 * 140 * @param http a pointer to an evhttp object 141 * @param fd a socket fd that is ready for accepting connections 142 * @return Handle for the socket on success, NULL on failure. 143 * @see evhttp_accept_socket(), evhttp_del_accept_socket() 144 */ 145 EVENT2_EXPORT_SYMBOL 146 struct evhttp_bound_socket *evhttp_accept_socket_with_handle(struct evhttp *http, evutil_socket_t fd); 147 148 /** 149 * The most low-level evhttp_bind/accept method: takes an evconnlistener, and 150 * returns an evhttp_bound_socket. The listener will be freed when the bound 151 * socket is freed. 152 */ 153 EVENT2_EXPORT_SYMBOL 154 struct evhttp_bound_socket *evhttp_bind_listener(struct evhttp *http, struct evconnlistener *listener); 155 156 /** 157 * Return the listener used to implement a bound socket. 158 */ 159 EVENT2_EXPORT_SYMBOL 160 struct evconnlistener *evhttp_bound_socket_get_listener(struct evhttp_bound_socket *bound); 161 162 typedef void evhttp_bound_socket_foreach_fn(struct evhttp_bound_socket *, void *); 163 /** 164 * Applies the function specified in the first argument to all 165 * evhttp_bound_sockets associated with "http". The user must not 166 * attempt to free or remove any connections, sockets or listeners 167 * in the callback "function". 168 * 169 * @param http pointer to an evhttp object 170 * @param function function to apply to every bound socket 171 * @param argument pointer value passed to function for every socket iterated 172 */ 173 EVENT2_EXPORT_SYMBOL 174 void evhttp_foreach_bound_socket(struct evhttp *http, evhttp_bound_socket_foreach_fn *function, void *argument); 175 176 /** 177 * Makes an HTTP server stop accepting connections on the specified socket 178 * 179 * This may be useful when a socket has been sent via file descriptor passing 180 * and is no longer needed by the current process. 181 * 182 * If you created this bound socket with evhttp_bind_socket_with_handle or 183 * evhttp_accept_socket_with_handle, this function closes the fd you provided. 184 * If you created this bound socket with evhttp_bind_listener, this function 185 * frees the listener you provided. 186 * 187 * \a bound_socket is an invalid pointer after this call returns. 188 * 189 * @param http a pointer to an evhttp object 190 * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle 191 * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() 192 */ 193 EVENT2_EXPORT_SYMBOL 194 void evhttp_del_accept_socket(struct evhttp *http, struct evhttp_bound_socket *bound_socket); 195 196 /** 197 * Get the raw file descriptor referenced by an evhttp_bound_socket. 198 * 199 * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle 200 * @return the file descriptor used by the bound socket 201 * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() 202 */ 203 EVENT2_EXPORT_SYMBOL 204 evutil_socket_t evhttp_bound_socket_get_fd(struct evhttp_bound_socket *bound_socket); 205 206 /** 207 * Free the previously created HTTP server. 208 * 209 * Works only if no requests are currently being served. 210 * 211 * @param http the evhttp server object to be freed 212 * @see evhttp_start() 213 */ 214 EVENT2_EXPORT_SYMBOL 215 void evhttp_free(struct evhttp* http); 216 217 /** XXX Document. */ 218 EVENT2_EXPORT_SYMBOL 219 void evhttp_set_max_headers_size(struct evhttp* http, ev_ssize_t max_headers_size); 220 /** XXX Document. */ 221 EVENT2_EXPORT_SYMBOL 222 void evhttp_set_max_body_size(struct evhttp* http, ev_ssize_t max_body_size); 223 224 /** 225 Set the value to use for the Content-Type header when none was provided. If 226 the content type string is NULL, the Content-Type header will not be 227 automatically added. 228 229 @param http the http server on which to set the default content type 230 @param content_type the value for the Content-Type header 231 */ 232 EVENT2_EXPORT_SYMBOL 233 void evhttp_set_default_content_type(struct evhttp *http, 234 const char *content_type); 235 236 /** 237 Sets the what HTTP methods are supported in requests accepted by this 238 server, and passed to user callbacks. 239 240 If not supported they will generate a "405 Method not allowed" response. 241 242 By default this includes the following methods: GET, POST, HEAD, PUT, DELETE 243 244 @param http the http server on which to set the methods 245 @param methods bit mask constructed from evhttp_cmd_type values 246 */ 247 EVENT2_EXPORT_SYMBOL 248 void evhttp_set_allowed_methods(struct evhttp* http, ev_uint16_t methods); 249 250 /** 251 Set a callback for a specified URI 252 253 @param http the http sever on which to set the callback 254 @param path the path for which to invoke the callback 255 @param cb the callback function that gets invoked on requesting path 256 @param cb_arg an additional context argument for the callback 257 @return 0 on success, -1 if the callback existed already, -2 on failure 258 */ 259 EVENT2_EXPORT_SYMBOL 260 int evhttp_set_cb(struct evhttp *http, const char *path, 261 void (*cb)(struct evhttp_request *, void *), void *cb_arg); 262 263 /** Removes the callback for a specified URI */ 264 EVENT2_EXPORT_SYMBOL 265 int evhttp_del_cb(struct evhttp *, const char *); 266 267 /** 268 Set a callback for all requests that are not caught by specific callbacks 269 270 Invokes the specified callback for all requests that do not match any of 271 the previously specified request paths. This is catchall for requests not 272 specifically configured with evhttp_set_cb(). 273 274 @param http the evhttp server object for which to set the callback 275 @param cb the callback to invoke for any unmatched requests 276 @param arg an context argument for the callback 277 */ 278 EVENT2_EXPORT_SYMBOL 279 void evhttp_set_gencb(struct evhttp *http, 280 void (*cb)(struct evhttp_request *, void *), void *arg); 281 282 /** 283 Set a callback used to create new bufferevents for connections 284 to a given evhttp object. 285 286 You can use this to override the default bufferevent type -- for example, 287 to make this evhttp object use SSL bufferevents rather than unencrypted 288 ones. 289 290 New bufferevents must be allocated with no fd set on them. 291 292 @param http the evhttp server object for which to set the callback 293 @param cb the callback to invoke for incoming connections 294 @param arg an context argument for the callback 295 */ 296 EVENT2_EXPORT_SYMBOL 297 void evhttp_set_bevcb(struct evhttp *http, 298 struct bufferevent *(*cb)(struct event_base *, void *), void *arg); 299 300 /** 301 Adds a virtual host to the http server. 302 303 A virtual host is a newly initialized evhttp object that has request 304 callbacks set on it via evhttp_set_cb() or evhttp_set_gencb(). It 305 most not have any listing sockets associated with it. 306 307 If the virtual host has not been removed by the time that evhttp_free() 308 is called on the main http server, it will be automatically freed, too. 309 310 It is possible to have hierarchical vhosts. For example: A vhost 311 with the pattern *.example.com may have other vhosts with patterns 312 foo.example.com and bar.example.com associated with it. 313 314 @param http the evhttp object to which to add a virtual host 315 @param pattern the glob pattern against which the hostname is matched. 316 The match is case insensitive and follows otherwise regular shell 317 matching. 318 @param vhost the virtual host to add the regular http server. 319 @return 0 on success, -1 on failure 320 @see evhttp_remove_virtual_host() 321 */ 322 EVENT2_EXPORT_SYMBOL 323 int evhttp_add_virtual_host(struct evhttp* http, const char *pattern, 324 struct evhttp* vhost); 325 326 /** 327 Removes a virtual host from the http server. 328 329 @param http the evhttp object from which to remove the virtual host 330 @param vhost the virtual host to remove from the regular http server. 331 @return 0 on success, -1 on failure 332 @see evhttp_add_virtual_host() 333 */ 334 EVENT2_EXPORT_SYMBOL 335 int evhttp_remove_virtual_host(struct evhttp* http, struct evhttp* vhost); 336 337 /** 338 Add a server alias to an http object. The http object can be a virtual 339 host or the main server. 340 341 @param http the evhttp object 342 @param alias the alias to add 343 @see evhttp_add_remove_alias() 344 */ 345 EVENT2_EXPORT_SYMBOL 346 int evhttp_add_server_alias(struct evhttp *http, const char *alias); 347 348 /** 349 Remove a server alias from an http object. 350 351 @param http the evhttp object 352 @param alias the alias to remove 353 @see evhttp_add_server_alias() 354 */ 355 EVENT2_EXPORT_SYMBOL 356 int evhttp_remove_server_alias(struct evhttp *http, const char *alias); 357 358 /** 359 * Set the timeout for an HTTP request. 360 * 361 * @param http an evhttp object 362 * @param timeout_in_secs the timeout, in seconds 363 */ 364 EVENT2_EXPORT_SYMBOL 365 void evhttp_set_timeout(struct evhttp *http, int timeout_in_secs); 366 367 /** 368 * Set the timeout for an HTTP request. 369 * 370 * @param http an evhttp object 371 * @param tv the timeout, or NULL 372 */ 373 EVENT2_EXPORT_SYMBOL 374 void evhttp_set_timeout_tv(struct evhttp *http, const struct timeval* tv); 375 376 /* Read all the clients body, and only after this respond with an error if the 377 * clients body exceed max_body_size */ 378 #define EVHTTP_SERVER_LINGERING_CLOSE 0x0001 379 /** 380 * Set connection flags for HTTP server. 381 * 382 * @see EVHTTP_SERVER_* 383 * @return 0 on success, otherwise non zero (for example if flag doesn't 384 * supported). 385 */ 386 EVENT2_EXPORT_SYMBOL 387 int evhttp_set_flags(struct evhttp *http, int flags); 388 389 /* Request/Response functionality */ 390 391 /** 392 * Send an HTML error message to the client. 393 * 394 * @param req a request object 395 * @param error the HTTP error code 396 * @param reason a brief explanation of the error. If this is NULL, we'll 397 * just use the standard meaning of the error code. 398 */ 399 EVENT2_EXPORT_SYMBOL 400 void evhttp_send_error(struct evhttp_request *req, int error, 401 const char *reason); 402 403 /** 404 * Send an HTML reply to the client. 405 * 406 * The body of the reply consists of the data in databuf. After calling 407 * evhttp_send_reply() databuf will be empty, but the buffer is still 408 * owned by the caller and needs to be deallocated by the caller if 409 * necessary. 410 * 411 * @param req a request object 412 * @param code the HTTP response code to send 413 * @param reason a brief message to send with the response code 414 * @param databuf the body of the response 415 */ 416 EVENT2_EXPORT_SYMBOL 417 void evhttp_send_reply(struct evhttp_request *req, int code, 418 const char *reason, struct evbuffer *databuf); 419 420 /* Low-level response interface, for streaming/chunked replies */ 421 422 /** 423 Initiate a reply that uses Transfer-Encoding chunked. 424 425 This allows the caller to stream the reply back to the client and is 426 useful when either not all of the reply data is immediately available 427 or when sending very large replies. 428 429 The caller needs to supply data chunks with evhttp_send_reply_chunk() 430 and complete the reply by calling evhttp_send_reply_end(). 431 432 @param req a request object 433 @param code the HTTP response code to send 434 @param reason a brief message to send with the response code 435 */ 436 EVENT2_EXPORT_SYMBOL 437 void evhttp_send_reply_start(struct evhttp_request *req, int code, 438 const char *reason); 439 440 /** 441 Send another data chunk as part of an ongoing chunked reply. 442 443 The reply chunk consists of the data in databuf. After calling 444 evhttp_send_reply_chunk() databuf will be empty, but the buffer is 445 still owned by the caller and needs to be deallocated by the caller 446 if necessary. 447 448 @param req a request object 449 @param databuf the data chunk to send as part of the reply. 450 */ 451 EVENT2_EXPORT_SYMBOL 452 void evhttp_send_reply_chunk(struct evhttp_request *req, 453 struct evbuffer *databuf); 454 455 /** 456 Send another data chunk as part of an ongoing chunked reply. 457 458 The reply chunk consists of the data in databuf. After calling 459 evhttp_send_reply_chunk() databuf will be empty, but the buffer is 460 still owned by the caller and needs to be deallocated by the caller 461 if necessary. 462 463 @param req a request object 464 @param databuf the data chunk to send as part of the reply. 465 @param cb callback funcion 466 @param call back's argument. 467 */ 468 EVENT2_EXPORT_SYMBOL 469 void evhttp_send_reply_chunk_with_cb(struct evhttp_request *, struct evbuffer *, 470 void (*cb)(struct evhttp_connection *, void *), void *arg); 471 472 /** 473 Complete a chunked reply, freeing the request as appropriate. 474 475 @param req a request object 476 */ 477 EVENT2_EXPORT_SYMBOL 478 void evhttp_send_reply_end(struct evhttp_request *req); 479 480 /* 481 * Interfaces for making requests 482 */ 483 484 /** The different request types supported by evhttp. These are as specified 485 * in RFC2616, except for PATCH which is specified by RFC5789. 486 * 487 * By default, only some of these methods are accepted and passed to user 488 * callbacks; use evhttp_set_allowed_methods() to change which methods 489 * are allowed. 490 */ 491 enum evhttp_cmd_type { 492 EVHTTP_REQ_GET = 1 << 0, 493 EVHTTP_REQ_POST = 1 << 1, 494 EVHTTP_REQ_HEAD = 1 << 2, 495 EVHTTP_REQ_PUT = 1 << 3, 496 EVHTTP_REQ_DELETE = 1 << 4, 497 EVHTTP_REQ_OPTIONS = 1 << 5, 498 EVHTTP_REQ_TRACE = 1 << 6, 499 EVHTTP_REQ_CONNECT = 1 << 7, 500 EVHTTP_REQ_PATCH = 1 << 8 501 }; 502 503 /** a request object can represent either a request or a reply */ 504 enum evhttp_request_kind { EVHTTP_REQUEST, EVHTTP_RESPONSE }; 505 506 /** 507 * Create and return a connection object that can be used to for making HTTP 508 * requests. The connection object tries to resolve address and establish the 509 * connection when it is given an http request object. 510 * 511 * @param base the event_base to use for handling the connection 512 * @param dnsbase the dns_base to use for resolving host names; if not 513 * specified host name resolution will block. 514 * @param bev a bufferevent to use for connecting to the server; if NULL, a 515 * socket-based bufferevent will be created. This buffrevent will be freed 516 * when the connection closes. It must have no fd set on it. 517 * @param address the address to which to connect 518 * @param port the port to connect to 519 * @return an evhttp_connection object that can be used for making requests 520 */ 521 EVENT2_EXPORT_SYMBOL 522 struct evhttp_connection *evhttp_connection_base_bufferevent_new( 523 struct event_base *base, struct evdns_base *dnsbase, struct bufferevent* bev, const char *address, ev_uint16_t port); 524 525 /** 526 * Return the bufferevent that an evhttp_connection is using. 527 */ 528 EVENT2_EXPORT_SYMBOL 529 struct bufferevent* evhttp_connection_get_bufferevent(struct evhttp_connection *evcon); 530 531 /** 532 * Return the HTTP server associated with this connection, or NULL. 533 */ 534 EVENT2_EXPORT_SYMBOL 535 struct evhttp *evhttp_connection_get_server(struct evhttp_connection *evcon); 536 537 /** 538 * Creates a new request object that needs to be filled in with the request 539 * parameters. The callback is executed when the request completed or an 540 * error occurred. 541 */ 542 EVENT2_EXPORT_SYMBOL 543 struct evhttp_request *evhttp_request_new( 544 void (*cb)(struct evhttp_request *, void *), void *arg); 545 546 /** 547 * Enable delivery of chunks to requestor. 548 * @param cb will be called after every read of data with the same argument 549 * as the completion callback. Will never be called on an empty 550 * response. May drain the input buffer; it will be drained 551 * automatically on return. 552 */ 553 EVENT2_EXPORT_SYMBOL 554 void evhttp_request_set_chunked_cb(struct evhttp_request *, 555 void (*cb)(struct evhttp_request *, void *)); 556 557 /** 558 * Register callback for additional parsing of request headers. 559 * @param cb will be called after receiving and parsing the full header. 560 * It allows analyzing the header and possibly closing the connection 561 * by returning a value < 0. 562 */ 563 EVENT2_EXPORT_SYMBOL 564 void evhttp_request_set_header_cb(struct evhttp_request *, 565 int (*cb)(struct evhttp_request *, void *)); 566 567 /** 568 * The different error types supported by evhttp 569 * 570 * @see evhttp_request_set_error_cb() 571 */ 572 enum evhttp_request_error { 573 /** 574 * Timeout reached, also @see evhttp_connection_set_timeout() 575 */ 576 EVREQ_HTTP_TIMEOUT, 577 /** 578 * EOF reached 579 */ 580 EVREQ_HTTP_EOF, 581 /** 582 * Error while reading header, or invalid header 583 */ 584 EVREQ_HTTP_INVALID_HEADER, 585 /** 586 * Error encountered while reading or writing 587 */ 588 EVREQ_HTTP_BUFFER_ERROR, 589 /** 590 * The evhttp_cancel_request() called on this request. 591 */ 592 EVREQ_HTTP_REQUEST_CANCEL, 593 /** 594 * Body is greater then evhttp_connection_set_max_body_size() 595 */ 596 EVREQ_HTTP_DATA_TOO_LONG 597 }; 598 /** 599 * Set a callback for errors 600 * @see evhttp_request_error for error types. 601 * 602 * On error, both the error callback and the regular callback will be called, 603 * error callback is called before the regular callback. 604 **/ 605 EVENT2_EXPORT_SYMBOL 606 void evhttp_request_set_error_cb(struct evhttp_request *, 607 void (*)(enum evhttp_request_error, void *)); 608 609 /** 610 * Set a callback to be called on request completion of evhttp_send_* function. 611 * 612 * The callback function will be called on the completion of the request after 613 * the output data has been written and before the evhttp_request object 614 * is destroyed. This can be useful for tracking resources associated with a 615 * request (ex: timing metrics). 616 * 617 * @param req a request object 618 * @param cb callback function that will be called on request completion 619 * @param cb_arg an additional context argument for the callback 620 */ 621 EVENT2_EXPORT_SYMBOL 622 void evhttp_request_set_on_complete_cb(struct evhttp_request *req, 623 void (*cb)(struct evhttp_request *, void *), void *cb_arg); 624 625 /** Frees the request object and removes associated events. */ 626 EVENT2_EXPORT_SYMBOL 627 void evhttp_request_free(struct evhttp_request *req); 628 629 /** 630 * Create and return a connection object that can be used to for making HTTP 631 * requests. The connection object tries to resolve address and establish the 632 * connection when it is given an http request object. 633 * 634 * @param base the event_base to use for handling the connection 635 * @param dnsbase the dns_base to use for resolving host names; if not 636 * specified host name resolution will block. 637 * @param address the address to which to connect 638 * @param port the port to connect to 639 * @return an evhttp_connection object that can be used for making requests 640 */ 641 EVENT2_EXPORT_SYMBOL 642 struct evhttp_connection *evhttp_connection_base_new( 643 struct event_base *base, struct evdns_base *dnsbase, 644 const char *address, ev_uint16_t port); 645 646 /** 647 * Set family hint for DNS requests. 648 */ 649 EVENT2_EXPORT_SYMBOL 650 void evhttp_connection_set_family(struct evhttp_connection *evcon, 651 int family); 652 653 /* reuse connection address on retry */ 654 #define EVHTTP_CON_REUSE_CONNECTED_ADDR 0x0008 655 /* Try to read error, since server may already send and close 656 * connection, but if at that time we have some data to send then we 657 * can send get EPIPE and fail, while we can read that HTTP error. */ 658 #define EVHTTP_CON_READ_ON_WRITE_ERROR 0x0010 659 /* @see EVHTTP_SERVER_LINGERING_CLOSE */ 660 #define EVHTTP_CON_LINGERING_CLOSE 0x0020 661 /* Padding for public flags, @see EVHTTP_CON_* in http-internal.h */ 662 #define EVHTTP_CON_PUBLIC_FLAGS_END 0x100000 663 /** 664 * Set connection flags. 665 * 666 * @see EVHTTP_CON_* 667 * @return 0 on success, otherwise non zero (for example if flag doesn't 668 * supported). 669 */ 670 EVENT2_EXPORT_SYMBOL 671 int evhttp_connection_set_flags(struct evhttp_connection *evcon, 672 int flags); 673 674 /** Takes ownership of the request object 675 * 676 * Can be used in a request callback to keep onto the request until 677 * evhttp_request_free() is explicitly called by the user. 678 */ 679 EVENT2_EXPORT_SYMBOL 680 void evhttp_request_own(struct evhttp_request *req); 681 682 /** Returns 1 if the request is owned by the user */ 683 EVENT2_EXPORT_SYMBOL 684 int evhttp_request_is_owned(struct evhttp_request *req); 685 686 /** 687 * Returns the connection object associated with the request or NULL 688 * 689 * The user needs to either free the request explicitly or call 690 * evhttp_send_reply_end(). 691 */ 692 EVENT2_EXPORT_SYMBOL 693 struct evhttp_connection *evhttp_request_get_connection(struct evhttp_request *req); 694 695 /** 696 * Returns the underlying event_base for this connection 697 */ 698 EVENT2_EXPORT_SYMBOL 699 struct event_base *evhttp_connection_get_base(struct evhttp_connection *req); 700 701 EVENT2_EXPORT_SYMBOL 702 void evhttp_connection_set_max_headers_size(struct evhttp_connection *evcon, 703 ev_ssize_t new_max_headers_size); 704 705 EVENT2_EXPORT_SYMBOL 706 void evhttp_connection_set_max_body_size(struct evhttp_connection* evcon, 707 ev_ssize_t new_max_body_size); 708 709 /** Frees an http connection */ 710 EVENT2_EXPORT_SYMBOL 711 void evhttp_connection_free(struct evhttp_connection *evcon); 712 713 /** Disowns a given connection object 714 * 715 * Can be used to tell libevent to free the connection object after 716 * the last request has completed or failed. 717 */ 718 EVENT2_EXPORT_SYMBOL 719 void evhttp_connection_free_on_completion(struct evhttp_connection *evcon); 720 721 /** sets the ip address from which http connections are made */ 722 EVENT2_EXPORT_SYMBOL 723 void evhttp_connection_set_local_address(struct evhttp_connection *evcon, 724 const char *address); 725 726 /** sets the local port from which http connections are made */ 727 EVENT2_EXPORT_SYMBOL 728 void evhttp_connection_set_local_port(struct evhttp_connection *evcon, 729 ev_uint16_t port); 730 731 /** Sets the timeout in seconds for events related to this connection */ 732 EVENT2_EXPORT_SYMBOL 733 void evhttp_connection_set_timeout(struct evhttp_connection *evcon, 734 int timeout_in_secs); 735 736 /** Sets the timeout for events related to this connection. Takes a struct 737 * timeval. */ 738 EVENT2_EXPORT_SYMBOL 739 void evhttp_connection_set_timeout_tv(struct evhttp_connection *evcon, 740 const struct timeval *tv); 741 742 /** Sets the delay before retrying requests on this connection. This is only 743 * used if evhttp_connection_set_retries is used to make the number of retries 744 * at least one. Each retry after the first is twice as long as the one before 745 * it. */ 746 EVENT2_EXPORT_SYMBOL 747 void evhttp_connection_set_initial_retry_tv(struct evhttp_connection *evcon, 748 const struct timeval *tv); 749 750 /** Sets the retry limit for this connection - -1 repeats indefinitely */ 751 EVENT2_EXPORT_SYMBOL 752 void evhttp_connection_set_retries(struct evhttp_connection *evcon, 753 int retry_max); 754 755 /** Set a callback for connection close. */ 756 EVENT2_EXPORT_SYMBOL 757 void evhttp_connection_set_closecb(struct evhttp_connection *evcon, 758 void (*)(struct evhttp_connection *, void *), void *); 759 760 /** Get the remote address and port associated with this connection. */ 761 EVENT2_EXPORT_SYMBOL 762 void evhttp_connection_get_peer(struct evhttp_connection *evcon, 763 char **address, ev_uint16_t *port); 764 765 /** Get the remote address associated with this connection. 766 * extracted from getpeername() OR from nameserver. 767 * 768 * @return NULL if getpeername() return non success, 769 * or connection is not connected, 770 * otherwise it return pointer to struct sockaddr_storage */ 771 EVENT2_EXPORT_SYMBOL 772 const struct sockaddr* 773 evhttp_connection_get_addr(struct evhttp_connection *evcon); 774 775 /** 776 Make an HTTP request over the specified connection. 777 778 The connection gets ownership of the request. On failure, the 779 request object is no longer valid as it has been freed. 780 781 @param evcon the evhttp_connection object over which to send the request 782 @param req the previously created and configured request object 783 @param type the request type EVHTTP_REQ_GET, EVHTTP_REQ_POST, etc. 784 @param uri the URI associated with the request 785 @return 0 on success, -1 on failure 786 @see evhttp_cancel_request() 787 */ 788 EVENT2_EXPORT_SYMBOL 789 int evhttp_make_request(struct evhttp_connection *evcon, 790 struct evhttp_request *req, 791 enum evhttp_cmd_type type, const char *uri); 792 793 /** 794 Cancels a pending HTTP request. 795 796 Cancels an ongoing HTTP request. The callback associated with this request 797 is not executed and the request object is freed. If the request is 798 currently being processed, e.g. it is ongoing, the corresponding 799 evhttp_connection object is going to get reset. 800 801 A request cannot be canceled if its callback has executed already. A request 802 may be canceled reentrantly from its chunked callback. 803 804 @param req the evhttp_request to cancel; req becomes invalid after this call. 805 */ 806 EVENT2_EXPORT_SYMBOL 807 void evhttp_cancel_request(struct evhttp_request *req); 808 809 /** 810 * A structure to hold a parsed URI or Relative-Ref conforming to RFC3986. 811 */ 812 struct evhttp_uri; 813 814 /** Returns the request URI */ 815 EVENT2_EXPORT_SYMBOL 816 const char *evhttp_request_get_uri(const struct evhttp_request *req); 817 /** Returns the request URI (parsed) */ 818 EVENT2_EXPORT_SYMBOL 819 const struct evhttp_uri *evhttp_request_get_evhttp_uri(const struct evhttp_request *req); 820 /** Returns the request command */ 821 EVENT2_EXPORT_SYMBOL 822 enum evhttp_cmd_type evhttp_request_get_command(const struct evhttp_request *req); 823 824 EVENT2_EXPORT_SYMBOL 825 int evhttp_request_get_response_code(const struct evhttp_request *req); 826 EVENT2_EXPORT_SYMBOL 827 const char * evhttp_request_get_response_code_line(const struct evhttp_request *req); 828 829 /** Returns the input headers */ 830 EVENT2_EXPORT_SYMBOL 831 struct evkeyvalq *evhttp_request_get_input_headers(struct evhttp_request *req); 832 /** Returns the output headers */ 833 EVENT2_EXPORT_SYMBOL 834 struct evkeyvalq *evhttp_request_get_output_headers(struct evhttp_request *req); 835 /** Returns the input buffer */ 836 EVENT2_EXPORT_SYMBOL 837 struct evbuffer *evhttp_request_get_input_buffer(struct evhttp_request *req); 838 /** Returns the output buffer */ 839 EVENT2_EXPORT_SYMBOL 840 struct evbuffer *evhttp_request_get_output_buffer(struct evhttp_request *req); 841 /** Returns the host associated with the request. If a client sends an absolute 842 URI, the host part of that is preferred. Otherwise, the input headers are 843 searched for a Host: header. NULL is returned if no absolute URI or Host: 844 header is provided. */ 845 EVENT2_EXPORT_SYMBOL 846 const char *evhttp_request_get_host(struct evhttp_request *req); 847 848 /* Interfaces for dealing with HTTP headers */ 849 850 /** 851 Finds the value belonging to a header. 852 853 @param headers the evkeyvalq object in which to find the header 854 @param key the name of the header to find 855 @returns a pointer to the value for the header or NULL if the header 856 could not be found. 857 @see evhttp_add_header(), evhttp_remove_header() 858 */ 859 EVENT2_EXPORT_SYMBOL 860 const char *evhttp_find_header(const struct evkeyvalq *headers, 861 const char *key); 862 863 /** 864 Removes a header from a list of existing headers. 865 866 @param headers the evkeyvalq object from which to remove a header 867 @param key the name of the header to remove 868 @returns 0 if the header was removed, -1 otherwise. 869 @see evhttp_find_header(), evhttp_add_header() 870 */ 871 EVENT2_EXPORT_SYMBOL 872 int evhttp_remove_header(struct evkeyvalq *headers, const char *key); 873 874 /** 875 Adds a header to a list of existing headers. 876 877 @param headers the evkeyvalq object to which to add a header 878 @param key the name of the header 879 @param value the value belonging to the header 880 @returns 0 on success, -1 otherwise. 881 @see evhttp_find_header(), evhttp_clear_headers() 882 */ 883 EVENT2_EXPORT_SYMBOL 884 int evhttp_add_header(struct evkeyvalq *headers, const char *key, const char *value); 885 886 /** 887 Removes all headers from the header list. 888 889 @param headers the evkeyvalq object from which to remove all headers 890 */ 891 EVENT2_EXPORT_SYMBOL 892 void evhttp_clear_headers(struct evkeyvalq *headers); 893 894 /* Miscellaneous utility functions */ 895 896 897 /** 898 Helper function to encode a string for inclusion in a URI. All 899 characters are replaced by their hex-escaped (%22) equivalents, 900 except for characters explicitly unreserved by RFC3986 -- that is, 901 ASCII alphanumeric characters, hyphen, dot, underscore, and tilde. 902 903 The returned string must be freed by the caller. 904 905 @param str an unencoded string 906 @return a newly allocated URI-encoded string or NULL on failure 907 */ 908 EVENT2_EXPORT_SYMBOL 909 char *evhttp_encode_uri(const char *str); 910 911 /** 912 As evhttp_encode_uri, but if 'size' is nonnegative, treat the string 913 as being 'size' bytes long. This allows you to encode strings that 914 may contain 0-valued bytes. 915 916 The returned string must be freed by the caller. 917 918 @param str an unencoded string 919 @param size the length of the string to encode, or -1 if the string 920 is NUL-terminated 921 @param space_to_plus if true, space characters in 'str' are encoded 922 as +, not %20. 923 @return a newly allocate URI-encoded string, or NULL on failure. 924 */ 925 EVENT2_EXPORT_SYMBOL 926 char *evhttp_uriencode(const char *str, ev_ssize_t size, int space_to_plus); 927 928 /** 929 Helper function to sort of decode a URI-encoded string. Unlike 930 evhttp_get_decoded_uri, it decodes all plus characters that appear 931 _after_ the first question mark character, but no plusses that occur 932 before. This is not a good way to decode URIs in whole or in part. 933 934 The returned string must be freed by the caller 935 936 @deprecated This function is deprecated; you probably want to use 937 evhttp_get_decoded_uri instead. 938 939 @param uri an encoded URI 940 @return a newly allocated unencoded URI or NULL on failure 941 */ 942 EVENT2_EXPORT_SYMBOL 943 char *evhttp_decode_uri(const char *uri); 944 945 /** 946 Helper function to decode a URI-escaped string or HTTP parameter. 947 948 If 'decode_plus' is 1, then we decode the string as an HTTP parameter 949 value, and convert all plus ('+') characters to spaces. If 950 'decode_plus' is 0, we leave all plus characters unchanged. 951 952 The returned string must be freed by the caller. 953 954 @param uri a URI-encode encoded URI 955 @param decode_plus determines whether we convert '+' to space. 956 @param size_out if size_out is not NULL, *size_out is set to the size of the 957 returned string 958 @return a newly allocated unencoded URI or NULL on failure 959 */ 960 EVENT2_EXPORT_SYMBOL 961 char *evhttp_uridecode(const char *uri, int decode_plus, 962 size_t *size_out); 963 964 /** 965 Helper function to parse out arguments in a query. 966 967 Parsing a URI like 968 969 http://foo.com/?q=test&s=some+thing 970 971 will result in two entries in the key value queue. 972 973 The first entry is: key="q", value="test" 974 The second entry is: key="s", value="some thing" 975 976 @deprecated This function is deprecated as of Libevent 2.0.9. Use 977 evhttp_uri_parse and evhttp_parse_query_str instead. 978 979 @param uri the request URI 980 @param headers the head of the evkeyval queue 981 @return 0 on success, -1 on failure 982 */ 983 EVENT2_EXPORT_SYMBOL 984 int evhttp_parse_query(const char *uri, struct evkeyvalq *headers); 985 986 /** 987 Helper function to parse out arguments from the query portion of an 988 HTTP URI. 989 990 Parsing a query string like 991 992 q=test&s=some+thing 993 994 will result in two entries in the key value queue. 995 996 The first entry is: key="q", value="test" 997 The second entry is: key="s", value="some thing" 998 999 @param query_parse the query portion of the URI 1000 @param headers the head of the evkeyval queue 1001 @return 0 on success, -1 on failure 1002 */ 1003 EVENT2_EXPORT_SYMBOL 1004 int evhttp_parse_query_str(const char *uri, struct evkeyvalq *headers); 1005 1006 /** 1007 * Escape HTML character entities in a string. 1008 * 1009 * Replaces <, >, ", ' and & with <, >, ", 1010 * ' and & correspondingly. 1011 * 1012 * The returned string needs to be freed by the caller. 1013 * 1014 * @param html an unescaped HTML string 1015 * @return an escaped HTML string or NULL on error 1016 */ 1017 EVENT2_EXPORT_SYMBOL 1018 char *evhttp_htmlescape(const char *html); 1019 1020 /** 1021 * Return a new empty evhttp_uri with no fields set. 1022 */ 1023 EVENT2_EXPORT_SYMBOL 1024 struct evhttp_uri *evhttp_uri_new(void); 1025 1026 /** 1027 * Changes the flags set on a given URI. See EVHTTP_URI_* for 1028 * a list of flags. 1029 **/ 1030 EVENT2_EXPORT_SYMBOL 1031 void evhttp_uri_set_flags(struct evhttp_uri *uri, unsigned flags); 1032 1033 /** Return the scheme of an evhttp_uri, or NULL if there is no scheme has 1034 * been set and the evhttp_uri contains a Relative-Ref. */ 1035 EVENT2_EXPORT_SYMBOL 1036 const char *evhttp_uri_get_scheme(const struct evhttp_uri *uri); 1037 /** 1038 * Return the userinfo part of an evhttp_uri, or NULL if it has no userinfo 1039 * set. 1040 */ 1041 EVENT2_EXPORT_SYMBOL 1042 const char *evhttp_uri_get_userinfo(const struct evhttp_uri *uri); 1043 /** 1044 * Return the host part of an evhttp_uri, or NULL if it has no host set. 1045 * The host may either be a regular hostname (conforming to the RFC 3986 1046 * "regname" production), or an IPv4 address, or the empty string, or a 1047 * bracketed IPv6 address, or a bracketed 'IP-Future' address. 1048 * 1049 * Note that having a NULL host means that the URI has no authority 1050 * section, but having an empty-string host means that the URI has an 1051 * authority section with no host part. For example, 1052 * "mailto:user (at) example.com" has a host of NULL, but "file:///etc/motd" 1053 * has a host of "". 1054 */ 1055 EVENT2_EXPORT_SYMBOL 1056 const char *evhttp_uri_get_host(const struct evhttp_uri *uri); 1057 /** Return the port part of an evhttp_uri, or -1 if there is no port set. */ 1058 EVENT2_EXPORT_SYMBOL 1059 int evhttp_uri_get_port(const struct evhttp_uri *uri); 1060 /** Return the path part of an evhttp_uri, or NULL if it has no path set */ 1061 EVENT2_EXPORT_SYMBOL 1062 const char *evhttp_uri_get_path(const struct evhttp_uri *uri); 1063 /** Return the query part of an evhttp_uri (excluding the leading "?"), or 1064 * NULL if it has no query set */ 1065 EVENT2_EXPORT_SYMBOL 1066 const char *evhttp_uri_get_query(const struct evhttp_uri *uri); 1067 /** Return the fragment part of an evhttp_uri (excluding the leading "#"), 1068 * or NULL if it has no fragment set */ 1069 EVENT2_EXPORT_SYMBOL 1070 const char *evhttp_uri_get_fragment(const struct evhttp_uri *uri); 1071 1072 /** Set the scheme of an evhttp_uri, or clear the scheme if scheme==NULL. 1073 * Returns 0 on success, -1 if scheme is not well-formed. */ 1074 EVENT2_EXPORT_SYMBOL 1075 int evhttp_uri_set_scheme(struct evhttp_uri *uri, const char *scheme); 1076 /** Set the userinfo of an evhttp_uri, or clear the userinfo if userinfo==NULL. 1077 * Returns 0 on success, -1 if userinfo is not well-formed. */ 1078 EVENT2_EXPORT_SYMBOL 1079 int evhttp_uri_set_userinfo(struct evhttp_uri *uri, const char *userinfo); 1080 /** Set the host of an evhttp_uri, or clear the host if host==NULL. 1081 * Returns 0 on success, -1 if host is not well-formed. */ 1082 EVENT2_EXPORT_SYMBOL 1083 int evhttp_uri_set_host(struct evhttp_uri *uri, const char *host); 1084 /** Set the port of an evhttp_uri, or clear the port if port==-1. 1085 * Returns 0 on success, -1 if port is not well-formed. */ 1086 EVENT2_EXPORT_SYMBOL 1087 int evhttp_uri_set_port(struct evhttp_uri *uri, int port); 1088 /** Set the path of an evhttp_uri, or clear the path if path==NULL. 1089 * Returns 0 on success, -1 if path is not well-formed. */ 1090 EVENT2_EXPORT_SYMBOL 1091 int evhttp_uri_set_path(struct evhttp_uri *uri, const char *path); 1092 /** Set the query of an evhttp_uri, or clear the query if query==NULL. 1093 * The query should not include a leading "?". 1094 * Returns 0 on success, -1 if query is not well-formed. */ 1095 EVENT2_EXPORT_SYMBOL 1096 int evhttp_uri_set_query(struct evhttp_uri *uri, const char *query); 1097 /** Set the fragment of an evhttp_uri, or clear the fragment if fragment==NULL. 1098 * The fragment should not include a leading "#". 1099 * Returns 0 on success, -1 if fragment is not well-formed. */ 1100 EVENT2_EXPORT_SYMBOL 1101 int evhttp_uri_set_fragment(struct evhttp_uri *uri, const char *fragment); 1102 1103 /** 1104 * Helper function to parse a URI-Reference as specified by RFC3986. 1105 * 1106 * This function matches the URI-Reference production from RFC3986, 1107 * which includes both URIs like 1108 * 1109 * scheme://[[userinfo]@]foo.com[:port]]/[path][?query][#fragment] 1110 * 1111 * and relative-refs like 1112 * 1113 * [path][?query][#fragment] 1114 * 1115 * Any optional elements portions not present in the original URI are 1116 * left set to NULL in the resulting evhttp_uri. If no port is 1117 * specified, the port is set to -1. 1118 * 1119 * Note that no decoding is performed on percent-escaped characters in 1120 * the string; if you want to parse them, use evhttp_uridecode or 1121 * evhttp_parse_query_str as appropriate. 1122 * 1123 * Note also that most URI schemes will have additional constraints that 1124 * this function does not know about, and cannot check. For example, 1125 * mailto://www.example.com/cgi-bin/fortune.pl is not a reasonable 1126 * mailto url, http://www.example.com:99999/ is not a reasonable HTTP 1127 * URL, and ftp:username (at) example.com is not a reasonable FTP URL. 1128 * Nevertheless, all of these URLs conform to RFC3986, and this function 1129 * accepts all of them as valid. 1130 * 1131 * @param source_uri the request URI 1132 * @param flags Zero or more EVHTTP_URI_* flags to affect the behavior 1133 * of the parser. 1134 * @return uri container to hold parsed data, or NULL if there is error 1135 * @see evhttp_uri_free() 1136 */ 1137 EVENT2_EXPORT_SYMBOL 1138 struct evhttp_uri *evhttp_uri_parse_with_flags(const char *source_uri, 1139 unsigned flags); 1140 1141 /** Tolerate URIs that do not conform to RFC3986. 1142 * 1143 * Unfortunately, some HTTP clients generate URIs that, according to RFC3986, 1144 * are not conformant URIs. If you need to support these URIs, you can 1145 * do so by passing this flag to evhttp_uri_parse_with_flags. 1146 * 1147 * Currently, these changes are: 1148 * <ul> 1149 * <li> Nonconformant URIs are allowed to contain otherwise unreasonable 1150 * characters in their path, query, and fragment components. 1151 * </ul> 1152 */ 1153 #define EVHTTP_URI_NONCONFORMANT 0x01 1154 1155 /** Alias for evhttp_uri_parse_with_flags(source_uri, 0) */ 1156 EVENT2_EXPORT_SYMBOL 1157 struct evhttp_uri *evhttp_uri_parse(const char *source_uri); 1158 1159 /** 1160 * Free all memory allocated for a parsed uri. Only use this for URIs 1161 * generated by evhttp_uri_parse. 1162 * 1163 * @param uri container with parsed data 1164 * @see evhttp_uri_parse() 1165 */ 1166 EVENT2_EXPORT_SYMBOL 1167 void evhttp_uri_free(struct evhttp_uri *uri); 1168 1169 /** 1170 * Join together the uri parts from parsed data to form a URI-Reference. 1171 * 1172 * Note that no escaping of reserved characters is done on the members 1173 * of the evhttp_uri, so the generated string might not be a valid URI 1174 * unless the members of evhttp_uri are themselves valid. 1175 * 1176 * @param uri container with parsed data 1177 * @param buf destination buffer 1178 * @param limit destination buffer size 1179 * @return an joined uri as string or NULL on error 1180 * @see evhttp_uri_parse() 1181 */ 1182 EVENT2_EXPORT_SYMBOL 1183 char *evhttp_uri_join(struct evhttp_uri *uri, char *buf, size_t limit); 1184 1185 #ifdef __cplusplus 1186 } 1187 #endif 1188 1189 #endif /* EVENT2_HTTP_H_INCLUDED_ */ 1190
