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 | * copies 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 | * $Id: multi.h,v 1.45 2008-05-20 10:21:50 patrickm Exp $ |
24 | ***************************************************************************/ |
25 | /* |
26 | This is an "external" header file. Don't give away any internals here! |
27 | |
28 | GOALS |
29 | |
30 | o Enable a "pull" interface. The application that uses libcurl decides where |
31 | and when to ask libcurl to get/send data. |
32 | |
33 | o Enable multiple simultaneous transfers in the same thread without making it |
34 | complicated for the application. |
35 | |
36 | o Enable the application to select() on its own file descriptors and curl's |
37 | file descriptors simultaneous easily. |
38 | |
39 | */ |
40 | |
41 | /* |
42 | * This header file should not really need to include "curl.h" since curl.h |
43 | * itself includes this file and we expect user applications to do #include |
44 | * <curl/curl.h> without the need for especially including multi.h. |
45 | * |
46 | * For some reason we added this include here at one point, and rather than to |
47 | * break existing (wrongly written) libcurl applications, we leave it as-is |
48 | * but with this warning attached. |
49 | */ |
50 | #include "curl.h" |
51 | |
52 | #ifdef __cplusplus |
53 | extern "C" { |
54 | #endif |
55 | |
56 | typedef void CURLM; |
57 | |
58 | typedef enum { |
59 | CURLM_CALL_MULTI_PERFORM = -1, /* please call curl_multi_perform() or |
60 | curl_multi_socket*() soon */ |
61 | CURLM_OK, |
62 | CURLM_BAD_HANDLE, /* the passed-in handle is not a valid CURLM handle */ |
63 | CURLM_BAD_EASY_HANDLE, /* an easy handle was not good/valid */ |
64 | CURLM_OUT_OF_MEMORY, /* if you ever get this, you're in deep sh*t */ |
65 | CURLM_INTERNAL_ERROR, /* this is a libcurl bug */ |
66 | CURLM_BAD_SOCKET, /* the passed in socket argument did not match */ |
67 | CURLM_UNKNOWN_OPTION, /* curl_multi_setopt() with unsupported option */ |
68 | CURLM_LAST |
69 | } CURLMcode; |
70 | |
71 | /* just to make code nicer when using curl_multi_socket() you can now check |
72 | for CURLM_CALL_MULTI_SOCKET too in the same style it works for |
73 | curl_multi_perform() and CURLM_CALL_MULTI_PERFORM */ |
74 | #define CURLM_CALL_MULTI_SOCKET CURLM_CALL_MULTI_PERFORM |
75 | |
76 | typedef enum { |
77 | CURLMSG_NONE, /* first, not used */ |
78 | CURLMSG_DONE, /* This easy handle has completed. 'result' contains |
79 | the CURLcode of the transfer */ |
80 | CURLMSG_LAST /* last, not used */ |
81 | } CURLMSG; |
82 | |
83 | struct CURLMsg { |
84 | CURLMSG msg; /* what this message means */ |
85 | CURL *easy_handle; /* the handle it concerns */ |
86 | union { |
87 | void *whatever; /* message-specific data */ |
88 | CURLcode result; /* return code for transfer */ |
89 | } data; |
90 | }; |
91 | typedef struct CURLMsg CURLMsg; |
92 | |
93 | /* |
94 | * Name: curl_multi_init() |
95 | * |
96 | * Desc: inititalize multi-style curl usage |
97 | * |
98 | * Returns: a new CURLM handle to use in all 'curl_multi' functions. |
99 | */ |
100 | CURL_EXTERN CURLM *curl_multi_init(void); |
101 | |
102 | /* |
103 | * Name: curl_multi_add_handle() |
104 | * |
105 | * Desc: add a standard curl handle to the multi stack |
106 | * |
107 | * Returns: CURLMcode type, general multi error code. |
108 | */ |
109 | CURL_EXTERN CURLMcode curl_multi_add_handle(CURLM *multi_handle, |
110 | CURL *curl_handle); |
111 | |
112 | /* |
113 | * Name: curl_multi_remove_handle() |
114 | * |
115 | * Desc: removes a curl handle from the multi stack again |
116 | * |
117 | * Returns: CURLMcode type, general multi error code. |
118 | */ |
119 | CURL_EXTERN CURLMcode curl_multi_remove_handle(CURLM *multi_handle, |
120 | CURL *curl_handle); |
121 | |
122 | /* |
123 | * Name: curl_multi_fdset() |
124 | * |
125 | * Desc: Ask curl for its fd_set sets. The app can use these to select() or |
126 | * poll() on. We want curl_multi_perform() called as soon as one of |
127 | * them are ready. |
128 | * |
129 | * Returns: CURLMcode type, general multi error code. |
130 | */ |
131 | CURL_EXTERN CURLMcode curl_multi_fdset(CURLM *multi_handle, |
132 | fd_set *read_fd_set, |
133 | fd_set *write_fd_set, |
134 | fd_set *exc_fd_set, |
135 | int *max_fd); |
136 | |
137 | /* |
138 | * Name: curl_multi_perform() |
139 | * |
140 | * Desc: When the app thinks there's data available for curl it calls this |
141 | * function to read/write whatever there is right now. This returns |
142 | * as soon as the reads and writes are done. This function does not |
143 | * require that there actually is data available for reading or that |
144 | * data can be written, it can be called just in case. It returns |
145 | * the number of handles that still transfer data in the second |
146 | * argument's integer-pointer. |
147 | * |
148 | * Returns: CURLMcode type, general multi error code. *NOTE* that this only |
149 | * returns errors etc regarding the whole multi stack. There might |
150 | * still have occurred problems on invidual transfers even when this |
151 | * returns OK. |
152 | */ |
153 | CURL_EXTERN CURLMcode curl_multi_perform(CURLM *multi_handle, |
154 | int *running_handles); |
155 | |
156 | /* |
157 | * Name: curl_multi_cleanup() |
158 | * |
159 | * Desc: Cleans up and removes a whole multi stack. It does not free or |
160 | * touch any individual easy handles in any way. We need to define |
161 | * in what state those handles will be if this function is called |
162 | * in the middle of a transfer. |
163 | * |
164 | * Returns: CURLMcode type, general multi error code. |
165 | */ |
166 | CURL_EXTERN CURLMcode curl_multi_cleanup(CURLM *multi_handle); |
167 | |
168 | /* |
169 | * Name: curl_multi_info_read() |
170 | * |
171 | * Desc: Ask the multi handle if there's any messages/informationals from |
172 | * the individual transfers. Messages include informationals such as |
173 | * error code from the transfer or just the fact that a transfer is |
174 | * completed. More details on these should be written down as well. |
175 | * |
176 | * Repeated calls to this function will return a new struct each |
177 | * time, until a special "end of msgs" struct is returned as a signal |
178 | * that there is no more to get at this point. |
179 | * |
180 | * The data the returned pointer points to will not survive calling |
181 | * curl_multi_cleanup(). |
182 | * |
183 | * The 'CURLMsg' struct is meant to be very simple and only contain |
184 | * very basic informations. If more involved information is wanted, |
185 | * we will provide the particular "transfer handle" in that struct |
186 | * and that should/could/would be used in subsequent |
187 | * curl_easy_getinfo() calls (or similar). The point being that we |
188 | * must never expose complex structs to applications, as then we'll |
189 | * undoubtably get backwards compatibility problems in the future. |
190 | * |
191 | * Returns: A pointer to a filled-in struct, or NULL if it failed or ran out |
192 | * of structs. It also writes the number of messages left in the |
193 | * queue (after this read) in the integer the second argument points |
194 | * to. |
195 | */ |
196 | CURL_EXTERN CURLMsg *curl_multi_info_read(CURLM *multi_handle, |
197 | int *msgs_in_queue); |
198 | |
199 | /* |
200 | * Name: curl_multi_strerror() |
201 | * |
202 | * Desc: The curl_multi_strerror function may be used to turn a CURLMcode |
203 | * value into the equivalent human readable error string. This is |
204 | * useful for printing meaningful error messages. |
205 | * |
206 | * Returns: A pointer to a zero-terminated error message. |
207 | */ |
208 | CURL_EXTERN const char *curl_multi_strerror(CURLMcode); |
209 | |
210 | /* |
211 | * Name: curl_multi_socket() and |
212 | * curl_multi_socket_all() |
213 | * |
214 | * Desc: An alternative version of curl_multi_perform() that allows the |
215 | * application to pass in one of the file descriptors that have been |
216 | * detected to have "action" on them and let libcurl perform. |
217 | * See man page for details. |
218 | */ |
219 | #define CURL_POLL_NONE 0 |
220 | #define CURL_POLL_IN 1 |
221 | #define CURL_POLL_OUT 2 |
222 | #define CURL_POLL_INOUT 3 |
223 | #define CURL_POLL_REMOVE 4 |
224 | |
225 | #define CURL_SOCKET_TIMEOUT CURL_SOCKET_BAD |
226 | |
227 | #define CURL_CSELECT_IN 0x01 |
228 | #define CURL_CSELECT_OUT 0x02 |
229 | #define CURL_CSELECT_ERR 0x04 |
230 | |
231 | typedef int (*curl_socket_callback)(CURL *easy, /* easy handle */ |
232 | curl_socket_t s, /* socket */ |
233 | int what, /* see above */ |
234 | void *userp, /* private callback |
235 | pointer */ |
236 | void *socketp); /* private socket |
237 | pointer */ |
238 | /* |
239 | * Name: curl_multi_timer_callback |
240 | * |
241 | * Desc: Called by libcurl whenever the library detects a change in the |
242 | * maximum number of milliseconds the app is allowed to wait before |
243 | * curl_multi_socket() or curl_multi_perform() must be called |
244 | * (to allow libcurl's timed events to take place). |
245 | * |
246 | * Returns: The callback should return zero. |
247 | */ |
248 | typedef int (*curl_multi_timer_callback)(CURLM *multi, /* multi handle */ |
249 | long timeout_ms, /* see above */ |
250 | void *userp); /* private callback |
251 | pointer */ |
252 | |
253 | CURL_EXTERN CURLMcode curl_multi_socket(CURLM *multi_handle, curl_socket_t s, |
254 | int *running_handles); |
255 | |
256 | CURL_EXTERN CURLMcode curl_multi_socket_action(CURLM *multi_handle, |
257 | curl_socket_t s, |
258 | int ev_bitmask, |
259 | int *running_handles); |
260 | |
261 | CURL_EXTERN CURLMcode curl_multi_socket_all(CURLM *multi_handle, |
262 | int *running_handles); |
263 | |
264 | #ifndef CURL_ALLOW_OLD_MULTI_SOCKET |
265 | /* This macro below was added in 7.16.3 to push users who recompile to use |
266 | the new curl_multi_socket_action() instead of the old curl_multi_socket() |
267 | */ |
268 | #define curl_multi_socket(x,y,z) curl_multi_socket_action(x,y,0,z) |
269 | #endif |
270 | |
271 | /* |
272 | * Name: curl_multi_timeout() |
273 | * |
274 | * Desc: Returns the maximum number of milliseconds the app is allowed to |
275 | * wait before curl_multi_socket() or curl_multi_perform() must be |
276 | * called (to allow libcurl's timed events to take place). |
277 | * |
278 | * Returns: CURLM error code. |
279 | */ |
280 | CURL_EXTERN CURLMcode curl_multi_timeout(CURLM *multi_handle, |
281 | long *milliseconds); |
282 | |
283 | #undef CINIT /* re-using the same name as in curl.h */ |
284 | |
285 | #ifdef CURL_ISOCPP |
286 | #define CINIT(name,type,num) CURLMOPT_ ## name = CURLOPTTYPE_ ## type + num |
287 | #else |
288 | /* The macro "##" is ISO C, we assume pre-ISO C doesn't support it. */ |
289 | #define LONG CURLOPTTYPE_LONG |
290 | #define OBJECTPOINT CURLOPTTYPE_OBJECTPOINT |
291 | #define FUNCTIONPOINT CURLOPTTYPE_FUNCTIONPOINT |
292 | #define OFF_T CURLOPTTYPE_OFF_T |
293 | #define CINIT(name,type,number) CURLMOPT_/**/name = type + number |
294 | #endif |
295 | |
296 | typedef enum { |
297 | /* This is the socket callback function pointer */ |
298 | CINIT(SOCKETFUNCTION, FUNCTIONPOINT, 1), |
299 | |
300 | /* This is the argument passed to the socket callback */ |
301 | CINIT(SOCKETDATA, OBJECTPOINT, 2), |
302 | |
303 | /* set to 1 to enable pipelining for this multi handle */ |
304 | CINIT(PIPELINING, LONG, 3), |
305 | |
306 | /* This is the timer callback function pointer */ |
307 | CINIT(TIMERFUNCTION, FUNCTIONPOINT, 4), |
308 | |
309 | /* This is the argument passed to the timer callback */ |
310 | CINIT(TIMERDATA, OBJECTPOINT, 5), |
311 | |
312 | /* maximum number of entries in the connection cache */ |
313 | CINIT(MAXCONNECTS, LONG, 6), |
314 | |
315 | CURLMOPT_LASTENTRY /* the last unused */ |
316 | } CURLMoption; |
317 | |
318 | |
319 | /* |
320 | * Name: curl_multi_setopt() |
321 | * |
322 | * Desc: Sets options for the multi handle. |
323 | * |
324 | * Returns: CURLM error code. |
325 | */ |
326 | CURL_EXTERN CURLMcode curl_multi_setopt(CURLM *multi_handle, |
327 | CURLMoption option, ...); |
328 | |
329 | |
330 | /* |
331 | * Name: curl_multi_assign() |
332 | * |
333 | * Desc: This function sets an association in the multi handle between the |
334 | * given socket and a private pointer of the application. This is |
335 | * (only) useful for curl_multi_socket uses. |
336 | * |
337 | * Returns: CURLM error code. |
338 | */ |
339 | CURL_EXTERN CURLMcode curl_multi_assign(CURLM *multi_handle, |
340 | curl_socket_t sockfd, void *sockp); |
341 | |
342 | #ifdef __cplusplus |
343 | } /* end of extern "C" */ |
344 | #endif |
345 | |
346 | #endif |
347 | |