1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 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.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 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25 /* <DESC>
26 * Send SMTP email with the multi interface
27 * </DESC>
28 */
29
30 #include <string.h>
31 #include <curl/curl.h>
32
33 /* This is an example showing how to send mail using libcurl's SMTP
34 * capabilities. It builds on the smtp-mail.c example to demonstrate how to use
35 * libcurl's multi interface.
36 */
37
38 #define FROM_MAIL "<sender@example.com>"
39 #define TO_MAIL "<recipient@example.com>"
40 #define CC_MAIL "<info@example.com>"
41
42 static const char *payload_text =
43 "Date: Mon, 29 Nov 2010 21:54:29 +1100\r\n"
44 "To: " TO_MAIL "\r\n"
45 "From: " FROM_MAIL "\r\n"
46 "Cc: " CC_MAIL "\r\n"
47 "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@"
48 "rfcpedant.example.org>\r\n"
49 "Subject: SMTP example message\r\n"
50 "\r\n" /* empty line to divide headers from body, see RFC 5322 */
51 "The body of the message starts here.\r\n"
52 "\r\n"
53 "It could be a lot of lines, could be MIME encoded, whatever.\r\n"
54 "Check RFC 5322.\r\n";
55
56 struct upload_status {
57 size_t bytes_read;
58 };
59
payload_source(char * ptr,size_t size,size_t nmemb,void * userp)60 static size_t payload_source(char *ptr, size_t size, size_t nmemb, void *userp)
61 {
62 struct upload_status *upload_ctx = (struct upload_status *)userp;
63 const char *data;
64 size_t room = size * nmemb;
65
66 if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) {
67 return 0;
68 }
69
70 data = &payload_text[upload_ctx->bytes_read];
71
72 if(data) {
73 size_t len = strlen(data);
74 if(room < len)
75 len = room;
76 memcpy(ptr, data, len);
77 upload_ctx->bytes_read += len;
78
79 return len;
80 }
81
82 return 0;
83 }
84
main(void)85 int main(void)
86 {
87 CURL *curl;
88 CURLM *mcurl;
89 int still_running = 1;
90 struct curl_slist *recipients = NULL;
91 struct upload_status upload_ctx = { 0 };
92
93 curl_global_init(CURL_GLOBAL_DEFAULT);
94
95 curl = curl_easy_init();
96 if(!curl)
97 return 1;
98
99 mcurl = curl_multi_init();
100 if(!mcurl)
101 return 2;
102
103 /* This is the URL for your mailserver */
104 curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com");
105
106 /* Note that this option is not strictly required, omitting it results in
107 * libcurl sending the MAIL FROM command with empty sender data. All
108 * autoresponses should have an empty reverse-path, and should be directed
109 * to the address in the reverse-path which triggered them. Otherwise, they
110 * could cause an endless loop. See RFC 5321 Section 4.5.5 for more details.
111 */
112 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM_MAIL);
113
114 /* Add two recipients, in this particular case they correspond to the
115 * To: and Cc: addressees in the header, but they could be any kind of
116 * recipient. */
117 recipients = curl_slist_append(recipients, TO_MAIL);
118 recipients = curl_slist_append(recipients, CC_MAIL);
119 curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
120
121 /* We are using a callback function to specify the payload (the headers and
122 * body of the message). You could just use the CURLOPT_READDATA option to
123 * specify a FILE pointer to read from. */
124 curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source);
125 curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx);
126 curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
127
128 /* Tell the multi stack about our easy handle */
129 curl_multi_add_handle(mcurl, curl);
130
131 do {
132 CURLMcode mc = curl_multi_perform(mcurl, &still_running);
133
134 if(still_running)
135 /* wait for activity, timeout or "nothing" */
136 mc = curl_multi_poll(mcurl, NULL, 0, 1000, NULL);
137
138 if(mc)
139 break;
140
141 } while(still_running);
142
143 /* Free the list of recipients */
144 curl_slist_free_all(recipients);
145
146 /* Always cleanup */
147 curl_multi_remove_handle(mcurl, curl);
148 curl_multi_cleanup(mcurl);
149 curl_easy_cleanup(curl);
150 curl_global_cleanup();
151
152 return 0;
153 }
154
