1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2017, 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 * SMTP example using the multi interface 25 * </DESC> 26 */ 27 28 #include <string.h> 29 #include <curl/curl.h> 30 31 /* This is an example showing how to send mail using libcurl's SMTP 32 * capabilities. It builds on the smtp-mail.c example to demonstrate how to use 33 * libcurl's multi interface. 34 * 35 * Note that this example requires libcurl 7.20.0 or above. 36 */ 37 38 #define FROM "<sender (at) example.com>" 39 #define TO "<recipient (at) example.com>" 40 #define CC "<info (at) example.com>" 41 42 #define MULTI_PERFORM_HANG_TIMEOUT 60 * 1000 43 44 static const char *payload_text[] = { 45 "Date: Mon, 29 Nov 2010 21:54:29 +1100\r\n", 46 "To: " TO "\r\n", 47 "From: " FROM " (Example User)\r\n", 48 "Cc: " CC " (Another example User)\r\n", 49 "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@" 50 "rfcpedant.example.org>\r\n", 51 "Subject: SMTP multi example message\r\n", 52 "\r\n", /* empty line to divide headers from body, see RFC5322 */ 53 "The body of the message starts here.\r\n", 54 "\r\n", 55 "It could be a lot of lines, could be MIME encoded, whatever.\r\n", 56 "Check RFC5322.\r\n", 57 NULL 58 }; 59 60 struct upload_status { 61 int lines_read; 62 }; 63 64 static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp) 65 { 66 struct upload_status *upload_ctx = (struct upload_status *)userp; 67 const char *data; 68 69 if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) { 70 return 0; 71 } 72 73 data = payload_text[upload_ctx->lines_read]; 74 75 if(data) { 76 size_t len = strlen(data); 77 memcpy(ptr, data, len); 78 upload_ctx->lines_read++; 79 80 return len; 81 } 82 83 return 0; 84 } 85 86 static struct timeval tvnow(void) 87 { 88 struct timeval now; 89 90 /* time() returns the value of time in seconds since the epoch */ 91 now.tv_sec = (long)time(NULL); 92 now.tv_usec = 0; 93 94 return now; 95 } 96 97 static long tvdiff(struct timeval newer, struct timeval older) 98 { 99 return (newer.tv_sec - older.tv_sec) * 1000 + 100 (newer.tv_usec - older.tv_usec) / 1000; 101 } 102 103 int main(void) 104 { 105 CURL *curl; 106 CURLM *mcurl; 107 int still_running = 1; 108 struct timeval mp_start; 109 struct curl_slist *recipients = NULL; 110 struct upload_status upload_ctx; 111 112 upload_ctx.lines_read = 0; 113 114 curl_global_init(CURL_GLOBAL_DEFAULT); 115 116 curl = curl_easy_init(); 117 if(!curl) 118 return 1; 119 120 mcurl = curl_multi_init(); 121 if(!mcurl) 122 return 2; 123 124 /* This is the URL for your mailserver */ 125 curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com"); 126 127 /* Note that this option isn't strictly required, omitting it will result in 128 * libcurl sending the MAIL FROM command with empty sender data. All 129 * autoresponses should have an empty reverse-path, and should be directed 130 * to the address in the reverse-path which triggered them. Otherwise, they 131 * could cause an endless loop. See RFC 5321 Section 4.5.5 for more details. 132 */ 133 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM); 134 135 /* Add two recipients, in this particular case they correspond to the 136 * To: and Cc: addressees in the header, but they could be any kind of 137 * recipient. */ 138 recipients = curl_slist_append(recipients, TO); 139 recipients = curl_slist_append(recipients, CC); 140 curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients); 141 142 /* We're using a callback function to specify the payload (the headers and 143 * body of the message). You could just use the CURLOPT_READDATA option to 144 * specify a FILE pointer to read from. */ 145 curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source); 146 curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx); 147 curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L); 148 149 /* Tell the multi stack about our easy handle */ 150 curl_multi_add_handle(mcurl, curl); 151 152 /* Record the start time which we can use later */ 153 mp_start = tvnow(); 154 155 /* We start some action by calling perform right away */ 156 curl_multi_perform(mcurl, &still_running); 157 158 while(still_running) { 159 struct timeval timeout; 160 fd_set fdread; 161 fd_set fdwrite; 162 fd_set fdexcep; 163 int maxfd = -1; 164 int rc; 165 CURLMcode mc; /* curl_multi_fdset() return code */ 166 167 long curl_timeo = -1; 168 169 /* Initialise the file descriptors */ 170 FD_ZERO(&fdread); 171 FD_ZERO(&fdwrite); 172 FD_ZERO(&fdexcep); 173 174 /* Set a suitable timeout to play around with */ 175 timeout.tv_sec = 1; 176 timeout.tv_usec = 0; 177 178 curl_multi_timeout(mcurl, &curl_timeo); 179 if(curl_timeo >= 0) { 180 timeout.tv_sec = curl_timeo / 1000; 181 if(timeout.tv_sec > 1) 182 timeout.tv_sec = 1; 183 else 184 timeout.tv_usec = (curl_timeo % 1000) * 1000; 185 } 186 187 /* get file descriptors from the transfers */ 188 mc = curl_multi_fdset(mcurl, &fdread, &fdwrite, &fdexcep, &maxfd); 189 190 if(mc != CURLM_OK) { 191 fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc); 192 break; 193 } 194 195 /* On success the value of maxfd is guaranteed to be >= -1. We call 196 select(maxfd + 1, ...); specially in case of (maxfd == -1) there are 197 no fds ready yet so we call select(0, ...) --or Sleep() on Windows-- 198 to sleep 100ms, which is the minimum suggested value in the 199 curl_multi_fdset() doc. */ 200 201 if(maxfd == -1) { 202 #ifdef _WIN32 203 Sleep(100); 204 rc = 0; 205 #else 206 /* Portable sleep for platforms other than Windows. */ 207 struct timeval wait = { 0, 100 * 1000 }; /* 100ms */ 208 rc = select(0, NULL, NULL, NULL, &wait); 209 #endif 210 } 211 else { 212 /* Note that on some platforms 'timeout' may be modified by select(). 213 If you need access to the original value save a copy beforehand. */ 214 rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout); 215 } 216 217 if(tvdiff(tvnow(), mp_start) > MULTI_PERFORM_HANG_TIMEOUT) { 218 fprintf(stderr, 219 "ABORTING: Since it seems that we would have run forever.\n"); 220 break; 221 } 222 223 switch(rc) { 224 case -1: /* select error */ 225 break; 226 case 0: /* timeout */ 227 default: /* action */ 228 curl_multi_perform(mcurl, &still_running); 229 break; 230 } 231 } 232 233 /* Free the list of recipients */ 234 curl_slist_free_all(recipients); 235 236 /* Always cleanup */ 237 curl_multi_remove_handle(mcurl, curl); 238 curl_multi_cleanup(mcurl); 239 curl_easy_cleanup(curl); 240 curl_global_cleanup(); 241 242 return 0; 243 } 244