1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2016, 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 * 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@example.com>"
39 #define TO "<recipient@example.com>"
40 #define CC "<info@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
payload_source(void * ptr,size_t size,size_t nmemb,void * userp)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
tvnow(void)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
tvdiff(struct timeval newer,struct timeval older)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
main(void)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