1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2017, 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 /* <DESC> 23 * multi interface and debug callback 24 * </DESC> 25 */ 26 27 #include <stdio.h> 28 #include <string.h> 29 30 /* somewhat unix-specific */ 31 #include <sys/time.h> 32 #include <unistd.h> 33 34 /* curl stuff */ 35 #include <curl/curl.h> 36 37 typedef char bool; 38 #define TRUE 1 39 40 static 41 void dump(const char *text, 42 FILE *stream, unsigned char *ptr, size_t size, 43 bool nohex) 44 { 45 size_t i; 46 size_t c; 47 48 unsigned int width = 0x10; 49 50 if(nohex) 51 /* without the hex output, we can fit more on screen */ 52 width = 0x40; 53 54 fprintf(stream, "%s, %10.10ld bytes (0x%8.8lx)\n", 55 text, (long)size, (long)size); 56 57 for(i = 0; i<size; i += width) { 58 59 fprintf(stream, "%4.4lx: ", (long)i); 60 61 if(!nohex) { 62 /* hex not disabled, show it */ 63 for(c = 0; c < width; c++) 64 if(i + c < size) 65 fprintf(stream, "%02x ", ptr[i + c]); 66 else 67 fputs(" ", stream); 68 } 69 70 for(c = 0; (c < width) && (i + c < size); c++) { 71 /* check for 0D0A; if found, skip past and start a new line of output */ 72 if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D && 73 ptr[i + c + 1] == 0x0A) { 74 i += (c + 2 - width); 75 break; 76 } 77 fprintf(stream, "%c", 78 (ptr[i + c] >= 0x20) && (ptr[i + c]<0x80)?ptr[i + c]:'.'); 79 /* check again for 0D0A, to avoid an extra \n if it's at width */ 80 if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D && 81 ptr[i + c + 2] == 0x0A) { 82 i += (c + 3 - width); 83 break; 84 } 85 } 86 fputc('\n', stream); /* newline */ 87 } 88 fflush(stream); 89 } 90 91 static 92 int my_trace(CURL *handle, curl_infotype type, 93 unsigned char *data, size_t size, 94 void *userp) 95 { 96 const char *text; 97 98 (void)userp; 99 (void)handle; /* prevent compiler warning */ 100 101 switch(type) { 102 case CURLINFO_TEXT: 103 fprintf(stderr, "== Info: %s", data); 104 /* FALLTHROUGH */ 105 default: /* in case a new one is introduced to shock us */ 106 return 0; 107 108 case CURLINFO_HEADER_OUT: 109 text = "=> Send header"; 110 break; 111 case CURLINFO_DATA_OUT: 112 text = "=> Send data"; 113 break; 114 case CURLINFO_HEADER_IN: 115 text = "<= Recv header"; 116 break; 117 case CURLINFO_DATA_IN: 118 text = "<= Recv data"; 119 break; 120 } 121 122 dump(text, stderr, data, size, TRUE); 123 return 0; 124 } 125 126 /* 127 * Simply download a HTTP file. 128 */ 129 int main(void) 130 { 131 CURL *http_handle; 132 CURLM *multi_handle; 133 134 int still_running; /* keep number of running handles */ 135 136 http_handle = curl_easy_init(); 137 138 /* set the options (I left out a few, you'll get the point anyway) */ 139 curl_easy_setopt(http_handle, CURLOPT_URL, "http://www.example.com/"); 140 141 curl_easy_setopt(http_handle, CURLOPT_DEBUGFUNCTION, my_trace); 142 curl_easy_setopt(http_handle, CURLOPT_VERBOSE, 1L); 143 144 /* init a multi stack */ 145 multi_handle = curl_multi_init(); 146 147 /* add the individual transfers */ 148 curl_multi_add_handle(multi_handle, http_handle); 149 150 /* we start some action by calling perform right away */ 151 curl_multi_perform(multi_handle, &still_running); 152 153 do { 154 struct timeval timeout; 155 int rc; /* select() return code */ 156 CURLMcode mc; /* curl_multi_fdset() return code */ 157 158 fd_set fdread; 159 fd_set fdwrite; 160 fd_set fdexcep; 161 int maxfd = -1; 162 163 long curl_timeo = -1; 164 165 FD_ZERO(&fdread); 166 FD_ZERO(&fdwrite); 167 FD_ZERO(&fdexcep); 168 169 /* set a suitable timeout to play around with */ 170 timeout.tv_sec = 1; 171 timeout.tv_usec = 0; 172 173 curl_multi_timeout(multi_handle, &curl_timeo); 174 if(curl_timeo >= 0) { 175 timeout.tv_sec = curl_timeo / 1000; 176 if(timeout.tv_sec > 1) 177 timeout.tv_sec = 1; 178 else 179 timeout.tv_usec = (curl_timeo % 1000) * 1000; 180 } 181 182 /* get file descriptors from the transfers */ 183 mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd); 184 185 if(mc != CURLM_OK) { 186 fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc); 187 break; 188 } 189 190 /* On success the value of maxfd is guaranteed to be >= -1. We call 191 select(maxfd + 1, ...); specially in case of (maxfd == -1) there are 192 no fds ready yet so we call select(0, ...) --or Sleep() on Windows-- 193 to sleep 100ms, which is the minimum suggested value in the 194 curl_multi_fdset() doc. */ 195 196 if(maxfd == -1) { 197 #ifdef _WIN32 198 Sleep(100); 199 rc = 0; 200 #else 201 /* Portable sleep for platforms other than Windows. */ 202 struct timeval wait = { 0, 100 * 1000 }; /* 100ms */ 203 rc = select(0, NULL, NULL, NULL, &wait); 204 #endif 205 } 206 else { 207 /* Note that on some platforms 'timeout' may be modified by select(). 208 If you need access to the original value save a copy beforehand. */ 209 rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout); 210 } 211 212 switch(rc) { 213 case -1: 214 /* select error */ 215 still_running = 0; 216 printf("select() returns error, this is badness\n"); 217 break; 218 case 0: 219 default: 220 /* timeout or readable/writable sockets */ 221 curl_multi_perform(multi_handle, &still_running); 222 break; 223 } 224 } while(still_running); 225 226 curl_multi_cleanup(multi_handle); 227 228 curl_easy_cleanup(http_handle); 229 230 return 0; 231 } 232