1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 2012 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23 /* <DESC>
24 * demonstrate the use of multi socket interface with boost::asio
25 * </DESC>
26 */
27 /*
28 * This program is in c++ and uses boost::asio instead of libevent/libev.
29 * Requires boost::asio, boost::bind and boost::system
30 *
31 * This is an adaptation of libcurl's "hiperfifo.c" and "evhiperfifo.c"
32 * sample programs. This example implements a subset of the functionality from
33 * hiperfifo.c, for full functionality refer hiperfifo.c or evhiperfifo.c
34 *
35 * Written by Lijo Antony based on hiperfifo.c by Jeff Pohlmeyer
36 *
37 * When running, the program creates an easy handle for a URL and
38 * uses the curl_multi API to fetch it.
39 *
40 * Note:
41 * For the sake of simplicity, URL is hard coded to "www.google.com"
42 *
43 * This is purely a demo app, all retrieved data is simply discarded by the write
44 * callback.
45 */
46
47
48 #include <curl/curl.h>
49 #include <boost/asio.hpp>
50 #include <boost/bind.hpp>
51 #include <iostream>
52
53 #define MSG_OUT stdout /* Send info to stdout, change to stderr if you want */
54
55 /* boost::asio related objects
56 * using global variables for simplicity
57 */
58 boost::asio::io_service io_service;
59 boost::asio::deadline_timer timer(io_service);
60 std::map<curl_socket_t, boost::asio::ip::tcp::socket *> socket_map;
61
62 /* Global information, common to all connections */
63 typedef struct _GlobalInfo
64 {
65 CURLM *multi;
66 int still_running;
67 } GlobalInfo;
68
69 /* Information associated with a specific easy handle */
70 typedef struct _ConnInfo
71 {
72 CURL *easy;
73 char *url;
74 GlobalInfo *global;
75 char error[CURL_ERROR_SIZE];
76 } ConnInfo;
77
78 static void timer_cb(const boost::system::error_code & error, GlobalInfo *g);
79
80 /* Update the event timer after curl_multi library calls */
multi_timer_cb(CURLM * multi,long timeout_ms,GlobalInfo * g)81 static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g)
82 {
83 fprintf(MSG_OUT, "\nmulti_timer_cb: timeout_ms %ld", timeout_ms);
84
85 /* cancel running timer */
86 timer.cancel();
87
88 if(timeout_ms > 0)
89 {
90 /* update timer */
91 timer.expires_from_now(boost::posix_time::millisec(timeout_ms));
92 timer.async_wait(boost::bind(&timer_cb, _1, g));
93 }
94 else
95 {
96 /* call timeout function immediately */
97 boost::system::error_code error; /*success*/
98 timer_cb(error, g);
99 }
100
101 return 0;
102 }
103
104 /* Die if we get a bad CURLMcode somewhere */
mcode_or_die(const char * where,CURLMcode code)105 static void mcode_or_die(const char *where, CURLMcode code)
106 {
107 if(CURLM_OK != code)
108 {
109 const char *s;
110 switch(code)
111 {
112 case CURLM_CALL_MULTI_PERFORM:
113 s = "CURLM_CALL_MULTI_PERFORM";
114 break;
115 case CURLM_BAD_HANDLE:
116 s = "CURLM_BAD_HANDLE";
117 break;
118 case CURLM_BAD_EASY_HANDLE:
119 s = "CURLM_BAD_EASY_HANDLE";
120 break;
121 case CURLM_OUT_OF_MEMORY:
122 s = "CURLM_OUT_OF_MEMORY";
123 break;
124 case CURLM_INTERNAL_ERROR:
125 s = "CURLM_INTERNAL_ERROR";
126 break;
127 case CURLM_UNKNOWN_OPTION:
128 s = "CURLM_UNKNOWN_OPTION";
129 break;
130 case CURLM_LAST:
131 s = "CURLM_LAST";
132 break;
133 default:
134 s = "CURLM_unknown";
135 break;
136 case CURLM_BAD_SOCKET:
137 s = "CURLM_BAD_SOCKET";
138 fprintf(MSG_OUT, "\nERROR: %s returns %s", where, s);
139 /* ignore this error */
140 return;
141 }
142
143 fprintf(MSG_OUT, "\nERROR: %s returns %s", where, s);
144
145 exit(code);
146 }
147 }
148
149 /* Check for completed transfers, and remove their easy handles */
check_multi_info(GlobalInfo * g)150 static void check_multi_info(GlobalInfo *g)
151 {
152 char *eff_url;
153 CURLMsg *msg;
154 int msgs_left;
155 ConnInfo *conn;
156 CURL *easy;
157 CURLcode res;
158
159 fprintf(MSG_OUT, "\nREMAINING: %d", g->still_running);
160
161 while((msg = curl_multi_info_read(g->multi, &msgs_left)))
162 {
163 if(msg->msg == CURLMSG_DONE)
164 {
165 easy = msg->easy_handle;
166 res = msg->data.result;
167 curl_easy_getinfo(easy, CURLINFO_PRIVATE, &conn);
168 curl_easy_getinfo(easy, CURLINFO_EFFECTIVE_URL, &eff_url);
169 fprintf(MSG_OUT, "\nDONE: %s => (%d) %s", eff_url, res, conn->error);
170 curl_multi_remove_handle(g->multi, easy);
171 free(conn->url);
172 curl_easy_cleanup(easy);
173 free(conn);
174 }
175 }
176 }
177
178 /* Called by asio when there is an action on a socket */
event_cb(GlobalInfo * g,boost::asio::ip::tcp::socket * tcp_socket,int action)179 static void event_cb(GlobalInfo *g, boost::asio::ip::tcp::socket *tcp_socket,
180 int action)
181 {
182 fprintf(MSG_OUT, "\nevent_cb: action=%d", action);
183
184 CURLMcode rc;
185 rc = curl_multi_socket_action(g->multi, tcp_socket->native_handle(), action,
186 &g->still_running);
187
188 mcode_or_die("event_cb: curl_multi_socket_action", rc);
189 check_multi_info(g);
190
191 if(g->still_running <= 0)
192 {
193 fprintf(MSG_OUT, "\nlast transfer done, kill timeout");
194 timer.cancel();
195 }
196 }
197
198 /* Called by asio when our timeout expires */
timer_cb(const boost::system::error_code & error,GlobalInfo * g)199 static void timer_cb(const boost::system::error_code & error, GlobalInfo *g)
200 {
201 if(!error)
202 {
203 fprintf(MSG_OUT, "\ntimer_cb: ");
204
205 CURLMcode rc;
206 rc = curl_multi_socket_action(g->multi, CURL_SOCKET_TIMEOUT, 0, &g->still_running);
207
208 mcode_or_die("timer_cb: curl_multi_socket_action", rc);
209 check_multi_info(g);
210 }
211 }
212
213 /* Clean up any data */
remsock(int * f,GlobalInfo * g)214 static void remsock(int *f, GlobalInfo *g)
215 {
216 fprintf(MSG_OUT, "\nremsock: ");
217
218 if(f)
219 {
220 free(f);
221 }
222 }
223
setsock(int * fdp,curl_socket_t s,CURL * e,int act,GlobalInfo * g)224 static void setsock(int *fdp, curl_socket_t s, CURL*e, int act, GlobalInfo*g)
225 {
226 fprintf(MSG_OUT, "\nsetsock: socket=%d, act=%d, fdp=%p", s, act, fdp);
227
228 std::map<curl_socket_t, boost::asio::ip::tcp::socket *>::iterator it = socket_map.find(s);
229
230 if(it == socket_map.end())
231 {
232 fprintf(MSG_OUT, "\nsocket %d is a c-ares socket, ignoring", s);
233
234 return;
235 }
236
237 boost::asio::ip::tcp::socket * tcp_socket = it->second;
238
239 *fdp = act;
240
241 if(act == CURL_POLL_IN)
242 {
243 fprintf(MSG_OUT, "\nwatching for socket to become readable");
244
245 tcp_socket->async_read_some(boost::asio::null_buffers(),
246 boost::bind(&event_cb, g, tcp_socket, act));
247 }
248 else if (act == CURL_POLL_OUT)
249 {
250 fprintf(MSG_OUT, "\nwatching for socket to become writable");
251
252 tcp_socket->async_write_some(boost::asio::null_buffers(),
253 boost::bind(&event_cb, g, tcp_socket, act));
254 }
255 else if(act == CURL_POLL_INOUT)
256 {
257 fprintf(MSG_OUT, "\nwatching for socket to become readable & writable");
258
259 tcp_socket->async_read_some(boost::asio::null_buffers(),
260 boost::bind(&event_cb, g, tcp_socket, act));
261
262 tcp_socket->async_write_some(boost::asio::null_buffers(),
263 boost::bind(&event_cb, g, tcp_socket, act));
264 }
265 }
266
addsock(curl_socket_t s,CURL * easy,int action,GlobalInfo * g)267 static void addsock(curl_socket_t s, CURL *easy, int action, GlobalInfo *g)
268 {
269 /* fdp is used to store current action */
270 int *fdp = (int *) calloc(sizeof(int), 1);
271
272 setsock(fdp, s, easy, action, g);
273 curl_multi_assign(g->multi, s, fdp);
274 }
275
276 /* CURLMOPT_SOCKETFUNCTION */
sock_cb(CURL * e,curl_socket_t s,int what,void * cbp,void * sockp)277 static int sock_cb(CURL *e, curl_socket_t s, int what, void *cbp, void *sockp)
278 {
279 fprintf(MSG_OUT, "\nsock_cb: socket=%d, what=%d, sockp=%p", s, what, sockp);
280
281 GlobalInfo *g = (GlobalInfo*) cbp;
282 int *actionp = (int *) sockp;
283 const char *whatstr[] = { "none", "IN", "OUT", "INOUT", "REMOVE"};
284
285 fprintf(MSG_OUT,
286 "\nsocket callback: s=%d e=%p what=%s ", s, e, whatstr[what]);
287
288 if(what == CURL_POLL_REMOVE)
289 {
290 fprintf(MSG_OUT, "\n");
291 remsock(actionp, g);
292 }
293 else
294 {
295 if(!actionp)
296 {
297 fprintf(MSG_OUT, "\nAdding data: %s", whatstr[what]);
298 addsock(s, e, what, g);
299 }
300 else
301 {
302 fprintf(MSG_OUT,
303 "\nChanging action from %s to %s",
304 whatstr[*actionp], whatstr[what]);
305 setsock(actionp, s, e, what, g);
306 }
307 }
308
309 return 0;
310 }
311
312 /* CURLOPT_WRITEFUNCTION */
write_cb(void * ptr,size_t size,size_t nmemb,void * data)313 static size_t write_cb(void *ptr, size_t size, size_t nmemb, void *data)
314 {
315
316 size_t written = size * nmemb;
317 char* pBuffer = (char *) malloc(written + 1);
318
319 strncpy(pBuffer, (const char *)ptr, written);
320 pBuffer[written] = '\0';
321
322 fprintf(MSG_OUT, "%s", pBuffer);
323
324 free(pBuffer);
325
326 return written;
327 }
328
329 /* CURLOPT_PROGRESSFUNCTION */
prog_cb(void * p,double dltotal,double dlnow,double ult,double uln)330 static int prog_cb(void *p, double dltotal, double dlnow, double ult,
331 double uln)
332 {
333 ConnInfo *conn = (ConnInfo *)p;
334
335 (void)ult;
336 (void)uln;
337
338 fprintf(MSG_OUT, "\nProgress: %s (%g/%g)", conn->url, dlnow, dltotal);
339 fprintf(MSG_OUT, "\nProgress: %s (%g)", conn->url, ult);
340
341 return 0;
342 }
343
344 /* CURLOPT_OPENSOCKETFUNCTION */
opensocket(void * clientp,curlsocktype purpose,struct curl_sockaddr * address)345 static curl_socket_t opensocket(void *clientp, curlsocktype purpose,
346 struct curl_sockaddr *address)
347 {
348 fprintf(MSG_OUT, "\nopensocket :");
349
350 curl_socket_t sockfd = CURL_SOCKET_BAD;
351
352 /* restrict to IPv4 */
353 if(purpose == CURLSOCKTYPE_IPCXN && address->family == AF_INET)
354 {
355 /* create a tcp socket object */
356 boost::asio::ip::tcp::socket *tcp_socket = new boost::asio::ip::tcp::socket(io_service);
357
358 /* open it and get the native handle*/
359 boost::system::error_code ec;
360 tcp_socket->open(boost::asio::ip::tcp::v4(), ec);
361
362 if(ec)
363 {
364 /* An error occurred */
365 std::cout << std::endl << "Couldn't open socket [" << ec << "][" << ec.message() << "]";
366 fprintf(MSG_OUT, "\nERROR: Returning CURL_SOCKET_BAD to signal error");
367 }
368 else
369 {
370 sockfd = tcp_socket->native_handle();
371 fprintf(MSG_OUT, "\nOpened socket %d", sockfd);
372
373 /* save it for monitoring */
374 socket_map.insert(std::pair<curl_socket_t, boost::asio::ip::tcp::socket *>(sockfd, tcp_socket));
375 }
376 }
377
378 return sockfd;
379 }
380
381 /* CURLOPT_CLOSESOCKETFUNCTION */
close_socket(void * clientp,curl_socket_t item)382 static int close_socket(void *clientp, curl_socket_t item)
383 {
384 fprintf(MSG_OUT, "\nclose_socket : %d", item);
385
386 std::map<curl_socket_t, boost::asio::ip::tcp::socket *>::iterator it = socket_map.find(item);
387
388 if(it != socket_map.end())
389 {
390 delete it->second;
391 socket_map.erase(it);
392 }
393
394 return 0;
395 }
396
397 /* Create a new easy handle, and add it to the global curl_multi */
new_conn(char * url,GlobalInfo * g)398 static void new_conn(char *url, GlobalInfo *g)
399 {
400 ConnInfo *conn;
401 CURLMcode rc;
402
403 conn = (ConnInfo *) calloc(1, sizeof(ConnInfo));
404
405 conn->easy = curl_easy_init();
406 if(!conn->easy)
407 {
408 fprintf(MSG_OUT, "\ncurl_easy_init() failed, exiting!");
409
410 exit(2);
411 }
412
413 conn->global = g;
414 conn->url = strdup(url);
415 curl_easy_setopt(conn->easy, CURLOPT_URL, conn->url);
416 curl_easy_setopt(conn->easy, CURLOPT_WRITEFUNCTION, write_cb);
417 curl_easy_setopt(conn->easy, CURLOPT_WRITEDATA, &conn);
418 curl_easy_setopt(conn->easy, CURLOPT_VERBOSE, 1L);
419 curl_easy_setopt(conn->easy, CURLOPT_ERRORBUFFER, conn->error);
420 curl_easy_setopt(conn->easy, CURLOPT_PRIVATE, conn);
421 curl_easy_setopt(conn->easy, CURLOPT_NOPROGRESS, 1L);
422 curl_easy_setopt(conn->easy, CURLOPT_PROGRESSFUNCTION, prog_cb);
423 curl_easy_setopt(conn->easy, CURLOPT_PROGRESSDATA, conn);
424 curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_TIME, 3L);
425 curl_easy_setopt(conn->easy, CURLOPT_LOW_SPEED_LIMIT, 10L);
426
427 /* call this function to get a socket */
428 curl_easy_setopt(conn->easy, CURLOPT_OPENSOCKETFUNCTION, opensocket);
429
430 /* call this function to close a socket */
431 curl_easy_setopt(conn->easy, CURLOPT_CLOSESOCKETFUNCTION, close_socket);
432
433 fprintf(MSG_OUT,
434 "\nAdding easy %p to multi %p (%s)", conn->easy, g->multi, url);
435 rc = curl_multi_add_handle(g->multi, conn->easy);
436 mcode_or_die("new_conn: curl_multi_add_handle", rc);
437
438 /* note that the add_handle() will set a time-out to trigger very soon so
439 that the necessary socket_action() call will be called by this app */
440 }
441
main(int argc,char ** argv)442 int main(int argc, char **argv)
443 {
444 GlobalInfo g;
445
446 (void)argc;
447 (void)argv;
448
449 memset(&g, 0, sizeof(GlobalInfo));
450 g.multi = curl_multi_init();
451
452 curl_multi_setopt(g.multi, CURLMOPT_SOCKETFUNCTION, sock_cb);
453 curl_multi_setopt(g.multi, CURLMOPT_SOCKETDATA, &g);
454 curl_multi_setopt(g.multi, CURLMOPT_TIMERFUNCTION, multi_timer_cb);
455 curl_multi_setopt(g.multi, CURLMOPT_TIMERDATA, &g);
456
457 new_conn((char *)"www.google.com", &g); /* add a URL */
458
459 /* enter io_service run loop */
460 io_service.run();
461
462 curl_multi_cleanup(g.multi);
463
464 fprintf(MSG_OUT, "\ndone.\n");
465
466 return 0;
467 }
468