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 showing how to send e-mails
25 * </DESC>
26 */
27
28 #include <stdio.h>
29 #include <string.h>
30 #include <curl/curl.h>
31
32 /* This is a simple example showing how to send mail using libcurl's SMTP
33 * capabilities. For an example of using the multi interface please see
34 * smtp-multi.c.
35 *
36 * Note that this example requires libcurl 7.20.0 or above.
37 */
38
39 #define FROM "<sender@example.org>"
40 #define TO "<addressee@example.net>"
41 #define CC "<info@example.org>"
42
43 static const char *payload_text[] = {
44 "Date: Mon, 29 Nov 2010 21:54:29 +1100\r\n",
45 "To: " TO "\r\n",
46 "From: " FROM "(Example User)\r\n",
47 "Cc: " CC "(Another example User)\r\n",
48 "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@"
49 "rfcpedant.example.org>\r\n",
50 "Subject: SMTP example message\r\n",
51 "\r\n", /* empty line to divide headers from body, see RFC5322 */
52 "The body of the message starts here.\r\n",
53 "\r\n",
54 "It could be a lot of lines, could be MIME encoded, whatever.\r\n",
55 "Check RFC5322.\r\n",
56 NULL
57 };
58
59 struct upload_status {
60 int lines_read;
61 };
62
payload_source(void * ptr,size_t size,size_t nmemb,void * userp)63 static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
64 {
65 struct upload_status *upload_ctx = (struct upload_status *)userp;
66 const char *data;
67
68 if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) {
69 return 0;
70 }
71
72 data = payload_text[upload_ctx->lines_read];
73
74 if(data) {
75 size_t len = strlen(data);
76 memcpy(ptr, data, len);
77 upload_ctx->lines_read++;
78
79 return len;
80 }
81
82 return 0;
83 }
84
main(void)85 int main(void)
86 {
87 CURL *curl;
88 CURLcode res = CURLE_OK;
89 struct curl_slist *recipients = NULL;
90 struct upload_status upload_ctx;
91
92 upload_ctx.lines_read = 0;
93
94 curl = curl_easy_init();
95 if(curl) {
96 /* This is the URL for your mailserver */
97 curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com");
98
99 /* Note that this option isn't strictly required, omitting it will result
100 * in libcurl sending the MAIL FROM command with empty sender data. All
101 * autoresponses should have an empty reverse-path, and should be directed
102 * to the address in the reverse-path which triggered them. Otherwise,
103 * they could cause an endless loop. See RFC 5321 Section 4.5.5 for more
104 * details.
105 */
106 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM);
107
108 /* Add two recipients, in this particular case they correspond to the
109 * To: and Cc: addressees in the header, but they could be any kind of
110 * recipient. */
111 recipients = curl_slist_append(recipients, TO);
112 recipients = curl_slist_append(recipients, CC);
113 curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
114
115 /* We're using a callback function to specify the payload (the headers and
116 * body of the message). You could just use the CURLOPT_READDATA option to
117 * specify a FILE pointer to read from. */
118 curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source);
119 curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx);
120 curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
121
122 /* Send the message */
123 res = curl_easy_perform(curl);
124
125 /* Check for errors */
126 if(res != CURLE_OK)
127 fprintf(stderr, "curl_easy_perform() failed: %s\n",
128 curl_easy_strerror(res));
129
130 /* Free the list of recipients */
131 curl_slist_free_all(recipients);
132
133 /* curl won't send the QUIT command until you call cleanup, so you should
134 * be able to re-use this connection for additional messages (setting
135 * CURLOPT_MAIL_FROM and CURLOPT_MAIL_RCPT as required, and calling
136 * curl_easy_perform() again. It may not be a good idea to keep the
137 * connection open for a very long time though (more than a few minutes
138 * may result in the server timing out the connection), and you do want to
139 * clean up in the end.
140 */
141 curl_easy_cleanup(curl);
142 }
143
144 return (int)res;
145 }
146