1 #ifndef __CURL_MULTI_H 2 #define __CURL_MULTI_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) 1998 - 2007, Daniel Stenberg, <daniel@haxx.se>, et al. 11 * 12 * This software is licensed as described in the file COPYING, which 13 * you should have received as part of this distribution. The terms 14 * are also available at http://curl.haxx.se/docs/copyright.html. 15 * 16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 17 * licensed versions of the software, and permit persons to whom the Software is 18 * furnished to do so, under the terms of the COPYING file. 19 * 20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 21 * KIND, either express or implied. 22 * 23 ***************************************************************************/ 24 25 #include "cafe/curl/cafeport.h" 26 27 /* 28 This is an "external" header file. do not give away any internals here! 29 30 GOALS 31 32 o Enable a "pull" interface. The application that uses libcurl decides where 33 and when to ask libcurl to get/send data. 34 35 o Enable multiple simultaneous transfers in the same thread without making it 36 complicated for the application. 37 38 o Enable the application to select() on its own file descriptors and curl's 39 file descriptors simultaneous easily. 40 41 */ 42 43 /* 44 * This header file should not really include "curl.h" since curl.h 45 * itself includes this file and we expect user applications to do #include 46 * <curl/curl.h> without the need for especially including multi.h. 47 * 48 * For some reason we added this include here at one point, and rather than to 49 * break existing (wrongly written) libcurl applications, we leave it as is 50 * but with this warning attached. 51 */ 52 #include "cafe/curl/curl.h" 53 54 #ifdef __cplusplus 55 extern "C" { 56 #endif 57 58 typedef void CURLM; 59 60 typedef enum { 61 CURLM_CALL_MULTI_PERFORM = -1, /* call curl_multi_perform() or 62 curl_multi_socket*() soon */ 63 CURLM_OK, 64 CURLM_BAD_HANDLE, /* the passed-in handle is not a valid CURLM handle */ 65 CURLM_BAD_EASY_HANDLE, /* an easy handle was not good/valid */ 66 CURLM_OUT_OF_MEMORY, /* out of memory */ 67 CURLM_INTERNAL_ERROR, /* this is a libcurl bug */ 68 CURLM_BAD_SOCKET, /* the passed in socket argument did not match */ 69 CURLM_UNKNOWN_OPTION, /* curl_multi_setopt() with unsupported option */ 70 CURLM_LAST 71 } CURLMcode; 72 73 /* just to make code nicer when using curl_multi_socket() you can now check 74 for CURLM_CALL_MULTI_SOCKET too in the same style it works for 75 curl_multi_perform() and CURLM_CALL_MULTI_PERFORM */ 76 #define CURLM_CALL_MULTI_SOCKET CURLM_CALL_MULTI_PERFORM 77 78 typedef enum { 79 CURLMSG_NONE, /* first, not used */ 80 CURLMSG_DONE, /* This easy handle has completed. 'result' contains 81 the CURLcode of the transfer */ 82 CURLMSG_LAST /* last, not used */ 83 } CURLMSG; 84 85 struct CURLMsg { 86 CURLMSG msg; /* what this message means */ 87 CURL *easy_handle; /* the handle it concerns */ 88 union { 89 void *whatever; /* message-specific data */ 90 CURLcode result; /* return code for transfer */ 91 } data; 92 }; 93 typedef struct CURLMsg CURLMsg; 94 95 /* 96 * Name: curl_multi_init() 97 * 98 * Desc: inititalize multi-style curl usage 99 * 100 * Returns: a new CURLM handle to use in all 'curl_multi' functions. 101 */ 102 CURL_EXTERN CURLM *curl_multi_init(void); 103 104 /* 105 * Name: curl_multi_add_handle() 106 * 107 * Desc: add a standard curl handle to the multi stack 108 * 109 * Returns: CURLMcode type, general multi error code. 110 */ 111 CURL_EXTERN CURLMcode curl_multi_add_handle(CURLM *multi_handle, 112 CURL *curl_handle); 113 114 /* 115 * Name: curl_multi_remove_handle() 116 * 117 * Desc: removes a curl handle from the multi stack again 118 * 119 * Returns: CURLMcode type, general multi error code. 120 */ 121 CURL_EXTERN CURLMcode curl_multi_remove_handle(CURLM *multi_handle, 122 CURL *curl_handle); 123 124 /* 125 * Name: curl_multi_fdset() 126 * 127 * Desc: Ask curl for its fd_set sets. The app can use these to select() or 128 * poll() on. We want curl_multi_perform() called as soon as one of 129 * them are ready. 130 * 131 * Returns: CURLMcode type, general multi error code. 132 */ 133 CURL_EXTERN CURLMcode curl_multi_fdset(CURLM *multi_handle, 134 fd_set *read_fd_set, 135 fd_set *write_fd_set, 136 fd_set *exc_fd_set, 137 int *max_fd); 138 139 /* 140 * Name: curl_multi_perform() 141 * 142 * Desc: When the app thinks there is data available for curl it calls this 143 * function to read/write whatever there is right now. This returns 144 * as soon as the reads and writes are done. This function does not 145 * require that there actually is data available for reading or that 146 * data can be written, it can be called just in case. It returns 147 * the number of handles that still transfer data in the second 148 * argument's integer-pointer. 149 * 150 * Returns: CURLMcode type, general multi error code. *NOTE* that this only 151 * returns errors for the whole multi stack. There might 152 * still have occurred problems on invidual transfers even when this 153 * returns OK. 154 */ 155 CURL_EXTERN CURLMcode curl_multi_perform(CURLM *multi_handle, 156 int *running_handles); 157 158 /* 159 * Name: curl_multi_cleanup() 160 * 161 * Desc: Cleans up and removes a whole multi stack. It does not free or 162 * touch any individual easy handles in any way. We must define 163 * in what state those handles will be if this function is called 164 * in the middle of a transfer. 165 * 166 * Returns: CURLMcode type, general multi error code. 167 */ 168 CURL_EXTERN CURLMcode curl_multi_cleanup(CURLM *multi_handle); 169 170 /* 171 * Name: curl_multi_info_read() 172 * 173 * Desc: Ask the multi handle if there is any messages/informationals from 174 * the individual transfers. Messages include informationals such as 175 * error code from the transfer or just the fact that a transfer is 176 * completed. More details on these should be written down as well. 177 * 178 * Repeated calls to this function will return a new struct each 179 * time, until a special "end of msgs" struct is returned as a signal 180 * that there is no more to get at this point. 181 * 182 * The data the returned pointer points to will not survive calling 183 * curl_multi_cleanup(). 184 * 185 * The 'CURLMsg' struct is meant to be very simple and only contain 186 * very basic informations. If more involved information is wanted, 187 * we will provide the particular "transfer handle" in that struct 188 * and that should/could/would be used in subsequent 189 * curl_easy_getinfo() calls (or similar). The point being that we 190 * must never expose complex structs to applications because then we will 191 * undoubtably get backward compatibility problems in the future. 192 * 193 * Returns: A pointer to a filled-in struct, or NULL if it failed or ran out 194 * of structs. It also writes the number of messages left in the 195 * queue (after this read) in the integer the second argument points 196 * to. 197 */ 198 CURL_EXTERN CURLMsg *curl_multi_info_read(CURLM *multi_handle, 199 int *msgs_in_queue); 200 201 /* 202 * Name: curl_multi_strerror() 203 * 204 * Desc: The curl_multi_strerror function may be used to turn a CURLMcode 205 * value into the equivalent human readable error string. This is 206 * useful for printing meaningful error messages. 207 * 208 * Returns: A pointer to a zero-terminated error message. 209 */ 210 CURL_EXTERN const char *curl_multi_strerror(CURLMcode); 211 212 /* 213 * Name: curl_multi_socket() and 214 * curl_multi_socket_all() 215 * 216 * Desc: An alternative version of curl_multi_perform() that allows the 217 * application to pass in one of the file descriptors that have been 218 * detected to have "action" on them and let libcurl perform. 219 * See man page for details. 220 */ 221 #define CURL_POLL_NONE 0 222 #define CURL_POLL_IN 1 223 #define CURL_POLL_OUT 2 224 #define CURL_POLL_INOUT 3 225 #define CURL_POLL_REMOVE 4 226 227 #define CURL_SOCKET_TIMEOUT CURL_SOCKET_BAD 228 229 #define CURL_CSELECT_IN 0x01 230 #define CURL_CSELECT_OUT 0x02 231 #define CURL_CSELECT_ERR 0x04 232 233 typedef int (*curl_socket_callback)(CURL *easy, /* easy handle */ 234 curl_socket_t s, /* socket */ 235 int what, /* see above */ 236 void *userp, /* private callback 237 pointer */ 238 void *socketp); /* private socket 239 pointer */ 240 /* 241 * Name: curl_multi_timer_callback 242 * 243 * Desc: Called by libcurl whenever the library detects a change in the 244 * maximum number of milliseconds the app is allowed to wait before 245 * curl_multi_socket() or curl_multi_perform() must be called 246 * (to allow libcurl's timed events to take place). 247 * 248 * Returns: The callback should return zero. 249 */ 250 typedef int (*curl_multi_timer_callback)(CURLM *multi, /* multi handle */ 251 long timeout_ms, /* see above */ 252 void *userp); /* private callback 253 pointer */ 254 255 CURL_EXTERN CURLMcode curl_multi_socket(CURLM *multi_handle, curl_socket_t s, 256 int *running_handles); 257 258 CURL_EXTERN CURLMcode curl_multi_socket_action(CURLM *multi_handle, 259 curl_socket_t s, 260 int ev_bitmask, 261 int *running_handles); 262 263 CURL_EXTERN CURLMcode curl_multi_socket_all(CURLM *multi_handle, 264 int *running_handles); 265 266 #ifndef CURL_ALLOW_OLD_MULTI_SOCKET 267 /* This macro below was added in 7.16.3 to push users who recompile to use 268 the new curl_multi_socket_action() instead of the old curl_multi_socket() 269 */ 270 #define curl_multi_socket(x,y,z) curl_multi_socket_action(x,y,0,z) 271 #endif 272 273 /* 274 * Name: curl_multi_timeout() 275 * 276 * Desc: Returns the maximum number of milliseconds the app is allowed to 277 * wait before curl_multi_socket() or curl_multi_perform() must be 278 * called (to allow libcurl's timed events to take place). 279 * 280 * Returns: CURLM error code. 281 */ 282 CURL_EXTERN CURLMcode curl_multi_timeout(CURLM *multi_handle, 283 long *milliseconds); 284 285 #undef CINIT /* re-using the same name as in curl.h */ 286 287 #ifdef CURL_ISOCPP 288 #define CINIT(name,type,num) CURLMOPT_ ## name = CURLOPTTYPE_ ## type + num 289 #else 290 /* The macro "##" is ISO C, we assume pre-ISO C does not support it. */ 291 #define LONG CURLOPTTYPE_LONG 292 #define OBJECTPOINT CURLOPTTYPE_OBJECTPOINT 293 #define FUNCTIONPOINT CURLOPTTYPE_FUNCTIONPOINT 294 #define OFF_T CURLOPTTYPE_OFF_T 295 #define CINIT(name,type,number) CURLMOPT_/**/name = type + number 296 #endif 297 298 typedef enum { 299 /* This is the socket callback function pointer */ 300 CINIT(SOCKETFUNCTION, FUNCTIONPOINT, 1), 301 302 /* This is the argument passed to the socket callback */ 303 CINIT(SOCKETDATA, OBJECTPOINT, 2), 304 305 /* set to 1 to enable pipelining for this multi handle */ 306 CINIT(PIPELINING, LONG, 3), 307 308 /* This is the timer callback function pointer */ 309 CINIT(TIMERFUNCTION, FUNCTIONPOINT, 4), 310 311 /* This is the argument passed to the timer callback */ 312 CINIT(TIMERDATA, OBJECTPOINT, 5), 313 314 /* maximum number of entries in the connection cache */ 315 CINIT(MAXCONNECTS, LONG, 6), 316 317 CURLMOPT_LASTENTRY /* the last unused */ 318 } CURLMoption; 319 320 321 /* 322 * Name: curl_multi_setopt() 323 * 324 * Desc: Sets options for the multi handle. 325 * 326 * Returns: CURLM error code. 327 */ 328 CURL_EXTERN CURLMcode curl_multi_setopt(CURLM *multi_handle, 329 CURLMoption option, ...); 330 331 332 /* 333 * Name: curl_multi_assign() 334 * 335 * Desc: This function sets an association in the multi handle between the 336 * given socket and a private pointer of the application. This is 337 * (only) useful for curl_multi_socket uses. 338 * 339 * Returns: CURLM error code. 340 */ 341 CURL_EXTERN CURLMcode curl_multi_assign(CURLM *multi_handle, 342 curl_socket_t sockfd, void *sockp); 343 344 #ifdef __cplusplus 345 } /* end of extern "C" */ 346 #endif 347 348 #endif 349