1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 2012 - 2015, Daniel Stenberg, <daniel (at) 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 214 static void remsock(int *f, GlobalInfo *g) 215 { 216 fprintf(MSG_OUT, "\nremsock: "); 217 218 if(f) 219 { 220 free(f); 221 } 222 } 223 224 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 } 266 267 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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 } 441 442 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
