1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2016, 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 * multi_socket API using libuv 25 * </DESC> 26 */ 27 /* Example application using the multi socket interface to download multiple 28 files in parallel, powered by libuv. 29 30 Requires libuv and (of course) libcurl. 31 32 See https://nikhilm.github.com/uvbook/ for more information on libuv. 33 */ 34 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <uv.h> 38 #include <curl/curl.h> 39 40 uv_loop_t *loop; 41 CURLM *curl_handle; 42 uv_timer_t timeout; 43 44 typedef struct curl_context_s { 45 uv_poll_t poll_handle; 46 curl_socket_t sockfd; 47 } curl_context_t; 48 49 curl_context_t* create_curl_context(curl_socket_t sockfd) 50 { 51 curl_context_t *context; 52 53 context = (curl_context_t *) malloc(sizeof *context); 54 55 context->sockfd = sockfd; 56 57 uv_poll_init_socket(loop, &context->poll_handle, sockfd); 58 context->poll_handle.data = context; 59 60 return context; 61 } 62 63 void curl_close_cb(uv_handle_t *handle) 64 { 65 curl_context_t *context = (curl_context_t *) handle->data; 66 free(context); 67 } 68 69 void destroy_curl_context(curl_context_t *context) 70 { 71 uv_close((uv_handle_t *) &context->poll_handle, curl_close_cb); 72 } 73 74 void add_download(const char *url, int num) 75 { 76 char filename[50]; 77 FILE *file; 78 CURL *handle; 79 80 snprintf(filename, 50, "%d.download", num); 81 82 file = fopen(filename, "wb"); 83 if(!file) { 84 fprintf(stderr, "Error opening %s\n", filename); 85 return; 86 } 87 88 handle = curl_easy_init(); 89 curl_easy_setopt(handle, CURLOPT_WRITEDATA, file); 90 curl_easy_setopt(handle, CURLOPT_PRIVATE, file); 91 curl_easy_setopt(handle, CURLOPT_URL, url); 92 curl_multi_add_handle(curl_handle, handle); 93 fprintf(stderr, "Added download %s -> %s\n", url, filename); 94 } 95 96 static void check_multi_info(void) 97 { 98 char *done_url; 99 CURLMsg *message; 100 int pending; 101 CURL *easy_handle; 102 FILE *file; 103 104 while((message = curl_multi_info_read(curl_handle, &pending))) { 105 switch(message->msg) { 106 case CURLMSG_DONE: 107 /* Do not use message data after calling curl_multi_remove_handle() and 108 curl_easy_cleanup(). As per curl_multi_info_read() docs: 109 "WARNING: The data the returned pointer points to will not survive 110 calling curl_multi_cleanup, curl_multi_remove_handle or 111 curl_easy_cleanup." */ 112 easy_handle = message->easy_handle; 113 114 curl_easy_getinfo(easy_handle, CURLINFO_EFFECTIVE_URL, &done_url); 115 curl_easy_getinfo(easy_handle, CURLINFO_PRIVATE, &file); 116 printf("%s DONE\n", done_url); 117 118 curl_multi_remove_handle(curl_handle, easy_handle); 119 curl_easy_cleanup(easy_handle); 120 if(file) { 121 fclose(file); 122 } 123 break; 124 125 default: 126 fprintf(stderr, "CURLMSG default\n"); 127 break; 128 } 129 } 130 } 131 132 void curl_perform(uv_poll_t *req, int status, int events) 133 { 134 int running_handles; 135 int flags = 0; 136 curl_context_t *context; 137 138 uv_timer_stop(&timeout); 139 140 if(events & UV_READABLE) 141 flags |= CURL_CSELECT_IN; 142 if(events & UV_WRITABLE) 143 flags |= CURL_CSELECT_OUT; 144 145 context = (curl_context_t *) req->data; 146 147 curl_multi_socket_action(curl_handle, context->sockfd, flags, 148 &running_handles); 149 150 check_multi_info(); 151 } 152 153 void on_timeout(uv_timer_t *req, int status) 154 { 155 int running_handles; 156 curl_multi_socket_action(curl_handle, CURL_SOCKET_TIMEOUT, 0, 157 &running_handles); 158 check_multi_info(); 159 } 160 161 void start_timeout(CURLM *multi, long timeout_ms, void *userp) 162 { 163 if(timeout_ms <= 0) 164 timeout_ms = 1; /* 0 means directly call socket_action, but we'll do it in 165 a bit */ 166 uv_timer_start(&timeout, on_timeout, timeout_ms, 0); 167 } 168 169 int handle_socket(CURL *easy, curl_socket_t s, int action, void *userp, 170 void *socketp) 171 { 172 curl_context_t *curl_context; 173 int events = 0; 174 175 switch(action) { 176 case CURL_POLL_IN: 177 case CURL_POLL_OUT: 178 case CURL_POLL_INOUT: 179 curl_context = socketp ? 180 (curl_context_t *) socketp : create_curl_context(s); 181 182 curl_multi_assign(curl_handle, s, (void *) curl_context); 183 184 if(action != CURL_POLL_IN) 185 events |= UV_WRITABLE; 186 if(action != CURL_POLL_OUT) 187 events |= UV_READABLE; 188 189 uv_poll_start(&curl_context->poll_handle, events, curl_perform); 190 break; 191 case CURL_POLL_REMOVE: 192 if(socketp) { 193 uv_poll_stop(&((curl_context_t*)socketp)->poll_handle); 194 destroy_curl_context((curl_context_t*) socketp); 195 curl_multi_assign(curl_handle, s, NULL); 196 } 197 break; 198 default: 199 abort(); 200 } 201 202 return 0; 203 } 204 205 int main(int argc, char **argv) 206 { 207 loop = uv_default_loop(); 208 209 if(argc <= 1) 210 return 0; 211 212 if(curl_global_init(CURL_GLOBAL_ALL)) { 213 fprintf(stderr, "Could not init curl\n"); 214 return 1; 215 } 216 217 uv_timer_init(loop, &timeout); 218 219 curl_handle = curl_multi_init(); 220 curl_multi_setopt(curl_handle, CURLMOPT_SOCKETFUNCTION, handle_socket); 221 curl_multi_setopt(curl_handle, CURLMOPT_TIMERFUNCTION, start_timeout); 222 223 while(argc-- > 1) { 224 add_download(argv[argc], argc); 225 } 226 227 uv_run(loop, UV_RUN_DEFAULT); 228 curl_multi_cleanup(curl_handle); 229 230 return 0; 231 } 232
