1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
#ifndef __CURL_MULTI_H
#define __CURL_MULTI_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2002, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
***************************************************************************/
/*
This is meant to be the "external" header file. Don't give away any
internals here!
This document presents a mixture of ideas from at least:
- Daniel Stenberg
- Steve Dekorte
- Sterling Hughes
- Ben Greear
-------------------------------------------
GOALS
o Enable a "pull" interface. The application that uses libcurl decides where
and when to ask libcurl to get/send data.
o Enable multiple simultaneous transfers in the same thread without making it
complicated for the application.
o Enable the application to select() on its own file descriptors and curl's
file descriptors simultaneous easily.
Example sources using this interface is here: ../multi/
*/
#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__)
#include <winsock.h>
#else
#include <sys/socket.h>
#include <sys/time.h>
#endif
#include "curl.h"
typedef void CURLM;
typedef enum {
CURLM_CALL_MULTI_PERFORM=-1, /* please call curl_multi_perform() soon */
CURLM_OK,
CURLM_BAD_HANDLE, /* the passed-in handle is not a valid CURLM handle */
CURLM_BAD_EASY_HANDLE, /* an easy handle was not good/valid */
CURLM_OUT_OF_MEMORY, /* if you ever get this, you're in deep sh*t */
CURLM_INTERNAL_ERROR, /* this is a libcurl bug */
CURLM_LAST
} CURLMcode;
typedef enum {
CURLMSG_NONE, /* first, not used */
CURLMSG_DONE, /* This easy handle has completed. 'whatever' points to
the CURLcode of the transfer */
CURLMSG_LAST /* last, not used */
} CURLMSG;
struct CURLMsg {
CURLMSG msg; /* what this message means */
CURL *easy_handle; /* the handle it concerns */
union {
void *whatever; /* message-specific data */
CURLcode result; /* return code for transfer */
} data;
};
typedef struct CURLMsg CURLMsg;
/*
* Name: curl_multi_init()
*
* Desc: inititalize multi-style curl usage
* Returns: a new CURLM handle to use in all 'curl_multi' functions.
*/
CURLM *curl_multi_init(void);
/*
* Name: curl_multi_add_handle()
*
* Desc: add a standard curl handle to the multi stack
* Returns: CURLMcode type, general multi error code.
*/
CURLMcode curl_multi_add_handle(CURLM *multi_handle,
CURL *curl_handle);
/*
* Name: curl_multi_remove_handle()
*
* Desc: removes a curl handle from the multi stack again
* Returns: CURLMcode type, general multi error code.
*/
CURLMcode curl_multi_remove_handle(CURLM *multi_handle,
CURL *curl_handle);
/*
* Name: curl_multi_fdset()
*
* Desc: Ask curl for its fd_set sets. The app can use these to select() or
* poll() on. We want curl_multi_perform() called as soon as one of
* them are ready.
* Returns: CURLMcode type, general multi error code.
*/
CURLMcode curl_multi_fdset(CURLM *multi_handle,
fd_set *read_fd_set,
fd_set *write_fd_set,
fd_set *exc_fd_set,
int *max_fd);
/*
* Name: curl_multi_perform()
*
* Desc: When the app thinks there's data available for curl it calls this
* function to read/write whatever there is right now. This returns
* as soon as the reads and writes are done. This function does not
* require that there actually is data available for reading or that
* data can be written, it can be called just in case. It returns
* the number of handles that still transfer data in the second
* argument's integer-pointer.
*
* Returns: CURLMcode type, general multi error code. *NOTE* that this only
* returns errors etc regarding the whole multi stack. There might
* still have occurred problems on invidual transfers even when this
* returns OK.
*/
CURLMcode curl_multi_perform(CURLM *multi_handle,
int *running_handles);
/*
* Name: curl_multi_cleanup()
*
* Desc: Cleans up and removes a whole multi stack. It does not free or
* touch any individual easy handles in any way. We need to define
* in what state those handles will be if this function is called
* in the middle of a transfer.
* Returns: CURLMcode type, general multi error code.
*/
CURLMcode curl_multi_cleanup(CURLM *multi_handle);
/*
* Name: curl_multi_info_read()
*
* Desc: Ask the multi handle if there's any messages/informationals from
* the individual transfers. Messages include informationals such as
* error code from the transfer or just the fact that a transfer is
* completed. More details on these should be written down as well.
*
* Repeated calls to this function will return a new struct each
* time, until a special "end of msgs" struct is returned as a signal
* that there is no more to get at this point.
*
* The data the returned pointer points to will not survive calling
* curl_multi_cleanup().
*
* The 'CURLMsg' struct is meant to be very simple and only contain
* very basic informations. If more involved information is wanted,
* we will provide the particular "transfer handle" in that struct
* and that should/could/would be used in subsequent
* curl_easy_getinfo() calls (or similar). The point being that we
* must never expose complex structs to applications, as then we'll
* undoubtably get backwards compatibility problems in the future.
*
* Returns: A pointer to a filled-in struct, or NULL if it failed or ran out
* of structs. It also writes the number of messages left in the
* queue (after this read) in the integer the second argument points
* to.
*/
CURLMsg *curl_multi_info_read(CURLM *multi_handle,
int *msgs_in_queue);
#endif
|
