1/* 2 * Copyright (c) 2000-2007 Niels Provos <provos@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_ 28#define _EVENT2_HTTP_H_ 29 30/* For int types. */ 31#include <event2/util.h> 32 33#ifdef __cplusplus 34extern "C" { 35#endif 36 37/* In case we haven't included the right headers yet. */ 38struct evbuffer; 39struct event_base; 40 41/** @file event2/http.h 42 * 43 * Basic support for HTTP serving. 44 * 45 * As Libevent is a library for dealing with event notification and most 46 * interesting applications are networked today, I have often found the 47 * need to write HTTP code. The following prototypes and definitions provide 48 * an application with a minimal interface for making HTTP requests and for 49 * creating a very simple HTTP server. 50 */ 51 52/* Response codes */ 53#define HTTP_OK 200 /**< request completed ok */ 54#define HTTP_NOCONTENT 204 /**< request does not have content */ 55#define HTTP_MOVEPERM 301 /**< the uri moved permanently */ 56#define HTTP_MOVETEMP 302 /**< the uri moved temporarily */ 57#define HTTP_NOTMODIFIED 304 /**< page was not modified from last */ 58#define HTTP_BADREQUEST 400 /**< invalid http request was made */ 59#define HTTP_NOTFOUND 404 /**< could not find content for uri */ 60#define HTTP_BADMETHOD 405 /**< method not allowed for this uri */ 61#define HTTP_ENTITYTOOLARGE 413 /**< */ 62#define HTTP_EXPECTATIONFAILED 417 /**< we can't handle this expectation */ 63#define HTTP_INTERNAL 500 /**< internal error */ 64#define HTTP_NOTIMPLEMENTED 501 /**< not implemented */ 65#define HTTP_SERVUNAVAIL 503 /**< the server is not available */ 66 67struct evhttp; 68struct evhttp_request; 69struct evkeyvalq; 70struct evhttp_bound_socket; 71struct evconnlistener; 72 73/** 74 * Create a new HTTP server. 75 * 76 * @param base (optional) the event base to receive the HTTP events 77 * @return a pointer to a newly initialized evhttp server structure 78 * @see evhttp_free() 79 */ 80struct evhttp *evhttp_new(struct event_base *base); 81 82/** 83 * Binds an HTTP server on the specified address and port. 84 * 85 * Can be called multiple times to bind the same http server 86 * to multiple different ports. 87 * 88 * @param http a pointer to an evhttp object 89 * @param address a string containing the IP address to listen(2) on 90 * @param port the port number to listen on 91 * @return 0 on success, -1 on failure. 92 * @see evhttp_accept_socket() 93 */ 94int evhttp_bind_socket(struct evhttp *http, const char *address, ev_uint16_t port); 95 96/** 97 * Like evhttp_bind_socket(), but returns a handle for referencing the socket. 98 * 99 * The returned pointer is not valid after \a http is freed. 100 * 101 * @param http a pointer to an evhttp object 102 * @param address a string containing the IP address to listen(2) on 103 * @param port the port number to listen on 104 * @return Handle for the socket on success, NULL on failure. 105 * @see evhttp_bind_socket(), evhttp_del_accept_socket() 106 */ 107struct evhttp_bound_socket *evhttp_bind_socket_with_handle(struct evhttp *http, const char *address, ev_uint16_t port); 108 109/** 110 * Makes an HTTP server accept connections on the specified socket. 111 * 112 * This may be useful to create a socket and then fork multiple instances 113 * of an http server, or when a socket has been communicated via file 114 * descriptor passing in situations where an http servers does not have 115 * permissions to bind to a low-numbered port. 116 * 117 * Can be called multiple times to have the http server listen to 118 * multiple different sockets. 119 * 120 * @param http a pointer to an evhttp object 121 * @param fd a socket fd that is ready for accepting connections 122 * @return 0 on success, -1 on failure. 123 * @see evhttp_bind_socket() 124 */ 125int evhttp_accept_socket(struct evhttp *http, evutil_socket_t fd); 126 127/** 128 * Like evhttp_accept_socket(), but returns a handle for referencing the socket. 129 * 130 * The returned pointer is not valid after \a http is freed. 131 * 132 * @param http a pointer to an evhttp object 133 * @param fd a socket fd that is ready for accepting connections 134 * @return Handle for the socket on success, NULL on failure. 135 * @see evhttp_accept_socket(), evhttp_del_accept_socket() 136 */ 137struct evhttp_bound_socket *evhttp_accept_socket_with_handle(struct evhttp *http, evutil_socket_t fd); 138 139/** 140 * The most low-level evhttp_bind/accept method: takes an evconnlistener, and 141 * returns an evhttp_bound_socket. The listener will be freed when the bound 142 * socket is freed. 143 */ 144struct evhttp_bound_socket *evhttp_bind_listener(struct evhttp *http, struct evconnlistener *listener); 145 146/** 147 * Return the listener used to implement a bound socket. 148 */ 149struct evconnlistener *evhttp_bound_socket_get_listener(struct evhttp_bound_socket *bound); 150 151/** 152 * Makes an HTTP server stop accepting connections on the specified socket 153 * 154 * This may be useful when a socket has been sent via file descriptor passing 155 * and is no longer needed by the current process. 156 * 157 * If you created this bound socket with evhttp_bind_socket_with_handle or 158 * evhttp_accept_socket_with_handle, this function closes the fd you provided. 159 * If you created this bound socket with evhttp_bind_listener, this function 160 * frees the listener you provided. 161 * 162 * \a bound_socket is an invalid pointer after this call returns. 163 * 164 * @param http a pointer to an evhttp object 165 * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle 166 * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() 167 */ 168void evhttp_del_accept_socket(struct evhttp *http, struct evhttp_bound_socket *bound_socket); 169 170/** 171 * Get the raw file descriptor referenced by an evhttp_bound_socket. 172 * 173 * @param bound_socket a handle returned by evhttp_{bind,accept}_socket_with_handle 174 * @return the file descriptor used by the bound socket 175 * @see evhttp_bind_socket_with_handle(), evhttp_accept_socket_with_handle() 176 */ 177evutil_socket_t evhttp_bound_socket_get_fd(struct evhttp_bound_socket *bound_socket); 178 179/** 180 * Free the previously created HTTP server. 181 * 182 * Works only if no requests are currently being served. 183 * 184 * @param http the evhttp server object to be freed 185 * @see evhttp_start() 186 */ 187void evhttp_free(struct evhttp* http); 188 189/** XXX Document. */ 190void evhttp_set_max_headers_size(struct evhttp* http, ev_ssize_t max_headers_size); 191/** XXX Document. */ 192void evhttp_set_max_body_size(struct evhttp* http, ev_ssize_t max_body_size); 193 194/** 195 Sets the what HTTP methods are supported in requests accepted by this 196 server, and passed to user callbacks. 197 198 If not supported they will generate a "405 Method not allowed" response. 199 200 By default this includes the following methods: GET, POST, HEAD, PUT, DELETE 201 202 @param http the http server on which to set the methods 203 @param methods bit mask constructed from evhttp_cmd_type values 204*/ 205void evhttp_set_allowed_methods(struct evhttp* http, ev_uint16_t methods); 206 207/** 208 Set a callback for a specified URI 209 210 @param http the http sever on which to set the callback 211 @param path the path for which to invoke the callback 212 @param cb the callback function that gets invoked on requesting path 213 @param cb_arg an additional context argument for the callback 214 @return 0 on success, -1 if the callback existed already, -2 on failure 215*/ 216int evhttp_set_cb(struct evhttp *http, const char *path, 217 void (*cb)(struct evhttp_request *, void *), void *cb_arg); 218 219/** Removes the callback for a specified URI */ 220int evhttp_del_cb(struct evhttp *, const char *); 221 222/** 223 Set a callback for all requests that are not caught by specific callbacks 224 225 Invokes the specified callback for all requests that do not match any of 226 the previously specified request paths. This is catchall for requests not 227 specifically configured with evhttp_set_cb(). 228 229 @param http the evhttp server object for which to set the callback 230 @param cb the callback to invoke for any unmatched requests 231 @param arg an context argument for the callback 232*/ 233void evhttp_set_gencb(struct evhttp *http, 234 void (*cb)(struct evhttp_request *, void *), void *arg); 235 236/** 237 Adds a virtual host to the http server. 238 239 A virtual host is a newly initialized evhttp object that has request 240 callbacks set on it via evhttp_set_cb() or evhttp_set_gencb(). It 241 most not have any listing sockets associated with it. 242 243 If the virtual host has not been removed by the time that evhttp_free() 244 is called on the main http server, it will be automatically freed, too. 245 246 It is possible to have hierarchical vhosts. For example: A vhost 247 with the pattern *.example.com may have other vhosts with patterns 248 foo.example.com and bar.example.com associated with it. 249 250 @param http the evhttp object to which to add a virtual host 251 @param pattern the glob pattern against which the hostname is matched. 252 The match is case insensitive and follows otherwise regular shell 253 matching. 254 @param vhost the virtual host to add the regular http server. 255 @return 0 on success, -1 on failure 256 @see evhttp_remove_virtual_host() 257*/ 258int evhttp_add_virtual_host(struct evhttp* http, const char *pattern, 259 struct evhttp* vhost); 260 261/** 262 Removes a virtual host from the http server. 263 264 @param http the evhttp object from which to remove the virtual host 265 @param vhost the virtual host to remove from the regular http server. 266 @return 0 on success, -1 on failure 267 @see evhttp_add_virtual_host() 268*/ 269int evhttp_remove_virtual_host(struct evhttp* http, struct evhttp* vhost); 270 271/** 272 Add a server alias to an http object. The http object can be a virtual 273 host or the main server. 274 275 @param http the evhttp object 276 @param alias the alias to add 277 @see evhttp_add_remove_alias() 278*/ 279int evhttp_add_server_alias(struct evhttp *http, const char *alias); 280 281/** 282 Remove a server alias from an http object. 283 284 @param http the evhttp object 285 @param alias the alias to remove 286 @see evhttp_add_server_alias() 287*/ 288int evhttp_remove_server_alias(struct evhttp *http, const char *alias); 289 290/** 291 * Set the timeout for an HTTP request. 292 * 293 * @param http an evhttp object 294 * @param timeout_in_secs the timeout, in seconds 295 */ 296void evhttp_set_timeout(struct evhttp *http, int timeout_in_secs); 297 298/* Request/Response functionality */ 299 300/** 301 * Send an HTML error message to the client. 302 * 303 * @param req a request object 304 * @param error the HTTP error code 305 * @param reason a brief explanation of the error. If this is NULL, we'll 306 * just use the standard meaning of the error code. 307 */ 308void evhttp_send_error(struct evhttp_request *req, int error, 309 const char *reason); 310 311/** 312 * Send an HTML reply to the client. 313 * 314 * The body of the reply consists of the data in databuf. After calling 315 * evhttp_send_reply() databuf will be empty, but the buffer is still 316 * owned by the caller and needs to be deallocated by the caller if 317 * necessary. 318 * 319 * @param req a request object 320 * @param code the HTTP response code to send 321 * @param reason a brief message to send with the response code 322 * @param databuf the body of the response 323 */ 324void evhttp_send_reply(struct evhttp_request *req, int code, 325 const char *reason, struct evbuffer *databuf); 326 327/* Low-level response interface, for streaming/chunked replies */ 328 329/** 330 Initiate a reply that uses Transfer-Encoding chunked. 331 332 This allows the caller to stream the reply back to the client and is 333 useful when either not all of the reply data is immediately available 334 or when sending very large replies. 335 336 The caller needs to supply data chunks with evhttp_send_reply_chunk() 337 and complete the reply by calling evhttp_send_reply_end(). 338 339 @param req a request object 340 @param code the HTTP response code to send 341 @param reason a brief message to send with the response code 342*/ 343void evhttp_send_reply_start(struct evhttp_request *req, int code, 344 const char *reason); 345 346/** 347 Send another data chunk as part of an ongoing chunked reply. 348 349 The reply chunk consists of the data in databuf. After calling 350 evhttp_send_reply_chunk() databuf will be empty, but the buffer is 351 still owned by the caller and needs to be deallocated by the caller 352 if necessary. 353 354 @param req a request object 355 @param databuf the data chunk to send as part of the reply. 356*/ 357void evhttp_send_reply_chunk(struct evhttp_request *req, 358 struct evbuffer *databuf); 359/** 360 Complete a chunked reply, freeing the request as appropriate. 361 362 @param req a request object 363*/ 364void evhttp_send_reply_end(struct evhttp_request *req); 365 366/* 367 * Interfaces for making requests 368 */ 369 370/** The different request types supported by evhttp. These are as specified 371 * in RFC2616, except for PATCH which is specified by RFC5789. 372 * 373 * By default, only some of these methods are accepted and passed to user 374 * callbacks; use evhttp_set_allowed_methods() to change which methods 375 * are allowed. 376 */ 377enum evhttp_cmd_type { 378 EVHTTP_REQ_GET = 1 << 0, 379 EVHTTP_REQ_POST = 1 << 1, 380 EVHTTP_REQ_HEAD = 1 << 2, 381 EVHTTP_REQ_PUT = 1 << 3, 382 EVHTTP_REQ_DELETE = 1 << 4, 383 EVHTTP_REQ_OPTIONS = 1 << 5, 384 EVHTTP_REQ_TRACE = 1 << 6, 385 EVHTTP_REQ_CONNECT = 1 << 7, 386 EVHTTP_REQ_PATCH = 1 << 8 387}; 388 389/** a request object can represent either a request or a reply */ 390enum evhttp_request_kind { EVHTTP_REQUEST, EVHTTP_RESPONSE }; 391 392/** 393 * Creates a new request object that needs to be filled in with the request 394 * parameters. The callback is executed when the request completed or an 395 * error occurred. 396 */ 397struct evhttp_request *evhttp_request_new( 398 void (*cb)(struct evhttp_request *, void *), void *arg); 399 400/** 401 * Enable delivery of chunks to requestor. 402 * @param cb will be called after every read of data with the same argument 403 * as the completion callback. Will never be called on an empty 404 * response. May drain the input buffer; it will be drained 405 * automatically on return. 406 */ 407void evhttp_request_set_chunked_cb(struct evhttp_request *, 408 void (*cb)(struct evhttp_request *, void *)); 409 410/** Frees the request object and removes associated events. */ 411void evhttp_request_free(struct evhttp_request *req); 412 413struct evdns_base; 414 415/** 416 * A connection object that can be used to for making HTTP requests. The 417 * connection object tries to resolve address and establish the connection 418 * when it is given an http request object. 419 * 420 * @param base the event_base to use for handling the connection 421 * @param dnsbase the dns_base to use for resolving host names; if not 422 * specified host name resolution will block. 423 * @param address the address to which to connect 424 * @param port the port to connect to 425 * @return an evhttp_connection object that can be used for making requests 426 */ 427struct evhttp_connection *evhttp_connection_base_new( 428 struct event_base *base, struct evdns_base *dnsbase, 429 const char *address, unsigned short port); 430 431/** 432 * Return the bufferevent that an evhttp_connection is using. 433 */ 434struct bufferevent *evhttp_connection_get_bufferevent( 435 struct evhttp_connection *evcon); 436 437/** Takes ownership of the request object 438 * 439 * Can be used in a request callback to keep onto the request until 440 * evhttp_request_free() is explicitly called by the user. 441 */ 442void evhttp_request_own(struct evhttp_request *req); 443 444/** Returns 1 if the request is owned by the user */ 445int evhttp_request_is_owned(struct evhttp_request *req); 446 447/** 448 * Returns the connection object associated with the request or NULL 449 * 450 * The user needs to either free the request explicitly or call 451 * evhttp_send_reply_end(). 452 */ 453struct evhttp_connection *evhttp_request_get_connection(struct evhttp_request *req); 454 455/** 456 * Returns the underlying event_base for this connection 457 */ 458struct event_base *evhttp_connection_get_base(struct evhttp_connection *req); 459 460void evhttp_connection_set_max_headers_size(struct evhttp_connection *evcon, 461 ev_ssize_t new_max_headers_size); 462 463void evhttp_connection_set_max_body_size(struct evhttp_connection* evcon, 464 ev_ssize_t new_max_body_size); 465 466/** Frees an http connection */ 467void evhttp_connection_free(struct evhttp_connection *evcon); 468 469/** sets the ip address from which http connections are made */ 470void evhttp_connection_set_local_address(struct evhttp_connection *evcon, 471 const char *address); 472 473/** sets the local port from which http connections are made */ 474void evhttp_connection_set_local_port(struct evhttp_connection *evcon, 475 ev_uint16_t port); 476 477/** Sets the timeout for events related to this connection */ 478void evhttp_connection_set_timeout(struct evhttp_connection *evcon, 479 int timeout_in_secs); 480 481/** Sets the retry limit for this connection - -1 repeats indefinitely */ 482void evhttp_connection_set_retries(struct evhttp_connection *evcon, 483 int retry_max); 484 485/** Set a callback for connection close. */ 486void evhttp_connection_set_closecb(struct evhttp_connection *evcon, 487 void (*)(struct evhttp_connection *, void *), void *); 488 489/** Get the remote address and port associated with this connection. */ 490void evhttp_connection_get_peer(struct evhttp_connection *evcon, 491 char **address, ev_uint16_t *port); 492 493/** 494 Make an HTTP request over the specified connection. 495 496 The connection gets ownership of the request. On failure, the 497 request object is no longer valid as it has been freed. 498 499 @param evcon the evhttp_connection object over which to send the request 500 @param req the previously created and configured request object 501 @param type the request type EVHTTP_REQ_GET, EVHTTP_REQ_POST, etc. 502 @param uri the URI associated with the request 503 @return 0 on success, -1 on failure 504 @see evhttp_cancel_request() 505*/ 506int evhttp_make_request(struct evhttp_connection *evcon, 507 struct evhttp_request *req, 508 enum evhttp_cmd_type type, const char *uri); 509 510/** 511 Cancels a pending HTTP request. 512 513 Cancels an ongoing HTTP request. The callback associated with this request 514 is not executed and the request object is freed. If the request is 515 currently being processed, e.g. it is ongoing, the corresponding 516 evhttp_connection object is going to get reset. 517 518 A request cannot be canceled if its callback has executed already. A request 519 may be canceled reentrantly from its chunked callback. 520 521 @param req the evhttp_request to cancel; req becomes invalid after this call. 522*/ 523void evhttp_cancel_request(struct evhttp_request *req); 524 525/** 526 * A structure to hold a parsed URI or Relative-Ref conforming to RFC3986. 527 */ 528struct evhttp_uri; 529 530/** Returns the request URI */ 531const char *evhttp_request_get_uri(const struct evhttp_request *req); 532/** Returns the request URI (parsed) */ 533const struct evhttp_uri *evhttp_request_get_evhttp_uri(const struct evhttp_request *req); 534/** Returns the request command */ 535enum evhttp_cmd_type evhttp_request_get_command(const struct evhttp_request *req); 536 537int evhttp_request_get_response_code(const struct evhttp_request *req); 538 539/** Returns the input headers */ 540struct evkeyvalq *evhttp_request_get_input_headers(struct evhttp_request *req); 541/** Returns the output headers */ 542struct evkeyvalq *evhttp_request_get_output_headers(struct evhttp_request *req); 543/** Returns the input buffer */ 544struct evbuffer *evhttp_request_get_input_buffer(struct evhttp_request *req); 545/** Returns the output buffer */ 546struct evbuffer *evhttp_request_get_output_buffer(struct evhttp_request *req); 547/** Returns the host associated with the request. If a client sends an absolute 548 URI, the host part of that is preferred. Otherwise, the input headers are 549 searched for a Host: header. NULL is returned if no absolute URI or Host: 550 header is provided. */ 551const char *evhttp_request_get_host(struct evhttp_request *req); 552 553/* Interfaces for dealing with HTTP headers */ 554 555/** 556 Finds the value belonging to a header. 557 558 @param headers the evkeyvalq object in which to find the header 559 @param key the name of the header to find 560 @returns a pointer to the value for the header or NULL if the header 561 count not be found. 562 @see evhttp_add_header(), evhttp_remove_header() 563*/ 564const char *evhttp_find_header(const struct evkeyvalq *headers, 565 const char *key); 566 567/** 568 Removes a header from a list of existing headers. 569 570 @param headers the evkeyvalq object from which to remove a header 571 @param key the name of the header to remove 572 @returns 0 if the header was removed, -1 otherwise. 573 @see evhttp_find_header(), evhttp_add_header() 574*/ 575int evhttp_remove_header(struct evkeyvalq *headers, const char *key); 576 577/** 578 Adds a header to a list of existing headers. 579 580 @param headers the evkeyvalq object to which to add a header 581 @param key the name of the header 582 @param value the value belonging to the header 583 @returns 0 on success, -1 otherwise. 584 @see evhttp_find_header(), evhttp_clear_headers() 585*/ 586int evhttp_add_header(struct evkeyvalq *headers, const char *key, const char *value); 587 588/** 589 Removes all headers from the header list. 590 591 @param headers the evkeyvalq object from which to remove all headers 592*/ 593void evhttp_clear_headers(struct evkeyvalq *headers); 594 595/* Miscellaneous utility functions */ 596 597 598/** 599 Helper function to encode a string for inclusion in a URI. All 600 characters are replaced by their hex-escaped (%22) equivalents, 601 except for characters explicitly unreserved by RFC3986 -- that is, 602 ASCII alphanumeric characters, hyphen, dot, underscore, and tilde. 603 604 The returned string must be freed by the caller. 605 606 @param str an unencoded string 607 @return a newly allocated URI-encoded string or NULL on failure 608 */ 609char *evhttp_encode_uri(const char *str); 610 611/** 612 As evhttp_encode_uri, but if 'size' is nonnegative, treat the string 613 as being 'size' bytes long. This allows you to encode strings that 614 may contain 0-valued bytes. 615 616 The returned string must be freed by the caller. 617 618 @param str an unencoded string 619 @param size the length of the string to encode, or -1 if the string 620 is NUL-terminated 621 @param space_to_plus if true, space characters in 'str' are encoded 622 as +, not %20. 623 @return a newly allocate URI-encoded string, or NULL on failure. 624 */ 625char *evhttp_uriencode(const char *str, ev_ssize_t size, int space_to_plus); 626 627/** 628 Helper function to sort of decode a URI-encoded string. Unlike 629 evhttp_get_decoded_uri, it decodes all plus characters that appear 630 _after_ the first question mark character, but no plusses that occur 631 before. This is not a good way to decode URIs in whole or in part. 632 633 The returned string must be freed by the caller 634 635 @deprecated This function is deprecated; you probably want to use 636 evhttp_get_decoded_uri instead. 637 638 @param uri an encoded URI 639 @return a newly allocated unencoded URI or NULL on failure 640 */ 641char *evhttp_decode_uri(const char *uri); 642 643/** 644 Helper function to decode a URI-escaped string or HTTP parameter. 645 646 If 'decode_plus' is 1, then we decode the string as an HTTP parameter 647 value, and convert all plus ('+') characters to spaces. If 648 'decode_plus' is 0, we leave all plus characters unchanged. 649 650 The returned string must be freed by the caller. 651 652 @param uri a URI-encode encoded URI 653 @param decode_plus determines whether we convert '+' to sapce. 654 @param size_out if size_out is not NULL, *size_out is set to the size of the 655 returned string 656 @return a newly allocated unencoded URI or NULL on failure 657 */ 658char *evhttp_uridecode(const char *uri, int decode_plus, 659 size_t *size_out); 660 661/** 662 Helper function to parse out arguments in a query. 663 664 Parsing a URI like 665 666 http://foo.com/?q=test&s=some+thing 667 668 will result in two entries in the key value queue. 669 670 The first entry is: key="q", value="test" 671 The second entry is: key="s", value="some thing" 672 673 @deprecated This function is deprecated as of Libevent 2.0.9. Use 674 evhttp_uri_parse and evhttp_parse_query_str instead. 675 676 @param uri the request URI 677 @param headers the head of the evkeyval queue 678 @return 0 on success, -1 on failure 679 */ 680int evhttp_parse_query(const char *uri, struct evkeyvalq *headers); 681 682/** 683 Helper function to parse out arguments from the query portion of an 684 HTTP URI. 685 686 Parsing a query string like 687 688 q=test&s=some+thing 689 690 will result in two entries in the key value queue. 691 692 The first entry is: key="q", value="test" 693 The second entry is: key="s", value="some thing" 694 695 @param query_parse the query portion of the URI 696 @param headers the head of the evkeyval queue 697 @return 0 on success, -1 on failure 698 */ 699int evhttp_parse_query_str(const char *uri, struct evkeyvalq *headers); 700 701/** 702 * Escape HTML character entities in a string. 703 * 704 * Replaces <, >, ", ' and & with <, >, ", 705 * ' and & correspondingly. 706 * 707 * The returned string needs to be freed by the caller. 708 * 709 * @param html an unescaped HTML string 710 * @return an escaped HTML string or NULL on error 711 */ 712char *evhttp_htmlescape(const char *html); 713 714/** 715 * Return a new empty evhttp_uri with no fields set. 716 */ 717struct evhttp_uri *evhttp_uri_new(void); 718 719/** 720 * Changes the flags set on a given URI. See EVHTTP_URI_* for 721 * a list of flags. 722 **/ 723void evhttp_uri_set_flags(struct evhttp_uri *uri, unsigned flags); 724 725/** Return the scheme of an evhttp_uri, or NULL if there is no scheme has 726 * been set and the evhttp_uri contains a Relative-Ref. */ 727const char *evhttp_uri_get_scheme(const struct evhttp_uri *uri); 728/** 729 * Return the userinfo part of an evhttp_uri, or NULL if it has no userinfo 730 * set. 731 */ 732const char *evhttp_uri_get_userinfo(const struct evhttp_uri *uri); 733/** 734 * Return the host part of an evhttp_uri, or NULL if it has no host set. 735 * The host may either be a regular hostname (conforming to the RFC 3986 736 * "regname" production), or an IPv4 address, or the empty string, or a 737 * bracketed IPv6 address, or a bracketed 'IP-Future' address. 738 * 739 * Note that having a NULL host means that the URI has no authority 740 * section, but having an empty-string host means that the URI has an 741 * authority section with no host part. For example, 742 * "mailto:user@example.com" has a host of NULL, but "file:///etc/motd" 743 * has a host of "". 744 */ 745const char *evhttp_uri_get_host(const struct evhttp_uri *uri); 746/** Return the port part of an evhttp_uri, or -1 if there is no port set. */ 747int evhttp_uri_get_port(const struct evhttp_uri *uri); 748/** Return the path part of an evhttp_uri, or NULL if it has no path set */ 749const char *evhttp_uri_get_path(const struct evhttp_uri *uri); 750/** Return the query part of an evhttp_uri (excluding the leading "?"), or 751 * NULL if it has no query set */ 752const char *evhttp_uri_get_query(const struct evhttp_uri *uri); 753/** Return the fragment part of an evhttp_uri (excluding the leading "#"), 754 * or NULL if it has no fragment set */ 755const char *evhttp_uri_get_fragment(const struct evhttp_uri *uri); 756 757/** Set the scheme of an evhttp_uri, or clear the scheme if scheme==NULL. 758 * Returns 0 on success, -1 if scheme is not well-formed. */ 759int evhttp_uri_set_scheme(struct evhttp_uri *uri, const char *scheme); 760/** Set the userinfo of an evhttp_uri, or clear the userinfo if userinfo==NULL. 761 * Returns 0 on success, -1 if userinfo is not well-formed. */ 762int evhttp_uri_set_userinfo(struct evhttp_uri *uri, const char *userinfo); 763/** Set the host of an evhttp_uri, or clear the host if host==NULL. 764 * Returns 0 on success, -1 if host is not well-formed. */ 765int evhttp_uri_set_host(struct evhttp_uri *uri, const char *host); 766/** Set the port of an evhttp_uri, or clear the port if port==-1. 767 * Returns 0 on success, -1 if port is not well-formed. */ 768int evhttp_uri_set_port(struct evhttp_uri *uri, int port); 769/** Set the path of an evhttp_uri, or clear the path if path==NULL. 770 * Returns 0 on success, -1 if path is not well-formed. */ 771int evhttp_uri_set_path(struct evhttp_uri *uri, const char *path); 772/** Set the query of an evhttp_uri, or clear the query if query==NULL. 773 * The query should not include a leading "?". 774 * Returns 0 on success, -1 if query is not well-formed. */ 775int evhttp_uri_set_query(struct evhttp_uri *uri, const char *query); 776/** Set the fragment of an evhttp_uri, or clear the fragment if fragment==NULL. 777 * The fragment should not include a leading "#". 778 * Returns 0 on success, -1 if fragment is not well-formed. */ 779int evhttp_uri_set_fragment(struct evhttp_uri *uri, const char *fragment); 780 781/** 782 * Helper function to parse a URI-Reference as specified by RFC3986. 783 * 784 * This function matches the URI-Reference production from RFC3986, 785 * which includes both URIs like 786 * 787 * scheme://[[userinfo]@]foo.com[:port]]/[path][?query][#fragment] 788 * 789 * and relative-refs like 790 * 791 * [path][?query][#fragment] 792 * 793 * Any optional elements portions not present in the original URI are 794 * left set to NULL in the resulting evhttp_uri. If no port is 795 * specified, the port is set to -1. 796 * 797 * Note that no decoding is performed on percent-escaped characters in 798 * the string; if you want to parse them, use evhttp_uridecode or 799 * evhttp_parse_query_str as appropriate. 800 * 801 * Note also that most URI schemes will have additional constraints that 802 * this function does not know about, and cannot check. For example, 803 * mailto://www.example.com/cgi-bin/fortune.pl is not a reasonable 804 * mailto url, http://www.example.com:99999/ is not a reasonable HTTP 805 * URL, and ftp:username@example.com is not a reasonable FTP URL. 806 * Nevertheless, all of these URLs conform to RFC3986, and this function 807 * accepts all of them as valid. 808 * 809 * @param source_uri the request URI 810 * @param flags Zero or more EVHTTP_URI_* flags to affect the behavior 811 * of the parser. 812 * @return uri container to hold parsed data, or NULL if there is error 813 * @see evhttp_uri_free() 814 */ 815struct evhttp_uri *evhttp_uri_parse_with_flags(const char *source_uri, 816 unsigned flags); 817 818/** Tolerate URIs that do not conform to RFC3986. 819 * 820 * Unfortunately, some HTTP clients generate URIs that, according to RFC3986, 821 * are not conformant URIs. If you need to support these URIs, you can 822 * do so by passing this flag to evhttp_uri_parse_with_flags. 823 * 824 * Currently, these changes are: 825 * <ul> 826 * <li> Nonconformant URIs are allowed to contain otherwise unreasonable 827 * characters in their path, query, and fragment components. 828 * </ul> 829 */ 830#define EVHTTP_URI_NONCONFORMANT 0x01 831 832/** Alias for evhttp_uri_parse_with_flags(source_uri, 0) */ 833struct evhttp_uri *evhttp_uri_parse(const char *source_uri); 834 835/** 836 * Free all memory allocated for a parsed uri. Only use this for URIs 837 * generated by evhttp_uri_parse. 838 * 839 * @param uri container with parsed data 840 * @see evhttp_uri_parse() 841 */ 842void evhttp_uri_free(struct evhttp_uri *uri); 843 844/** 845 * Join together the uri parts from parsed data to form a URI-Reference. 846 * 847 * Note that no escaping of reserved characters is done on the members 848 * of the evhttp_uri, so the generated string might not be a valid URI 849 * unless the members of evhttp_uri are themselves valid. 850 * 851 * @param uri container with parsed data 852 * @param buf destination buffer 853 * @param limit destination buffer size 854 * @return an joined uri as string or NULL on error 855 * @see evhttp_uri_parse() 856 */ 857char *evhttp_uri_join(struct evhttp_uri *uri, char *buf, size_t limit); 858 859#ifdef __cplusplus 860} 861#endif 862 863#endif /* _EVENT2_HTTP_H_ */ 864