summaryrefslogtreecommitdiff
path: root/docs/examples/smtp-mime.c
blob: ff54d04ca3f906c3eec5943634756c1d87d8a91b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/

/* <DESC>
 * SMTP example showing how to send mime e-mails
 * </DESC>
 */

#include <stdio.h>
#include <string.h>
#include <gnurl/curl.h>

/* This is a simple example showing how to send mime mail using libcurl's SMTP
 * capabilities. For an example of using the multi interface please see
 * smtp-multi.c.
 *
 * Note that this example requires libcurl 7.56.0 or above.
 */

#define FROM    "<sender@example.org>"
#define TO      "<addressee@example.net>"
#define CC      "<info@example.org>"

static const char *headers_text[] = {
  "Date: Tue, 22 Aug 2017 14:08:43 +0100",
  "To: " TO,
  "From: " FROM " (Example User)",
  "Cc: " CC " (Another example User)",
  "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@"
    "rfcpedant.example.org>",
  "Subject: example sending a MIME-formatted message",
  NULL
};

static const char inline_text[] =
  "This is the inline text message of the e-mail.\r\n"
  "\r\n"
  "  It could be a lot of lines that would be displayed in an e-mail\r\n"
  "viewer that is not able to handle HTML.\r\n";

static const char inline_html[] =
  "<html><body>\r\n"
  "<p>This is the inline <b>HTML</b> message of the e-mail.</p>"
  "<br />\r\n"
  "<p>It could be a lot of HTML data that would be displayed by "
  "e-mail viewers able to handle HTML.</p>"
  "</body></html>\r\n";


int main(void)
{
  CURL *curl;
  CURLcode res = CURLE_OK;

  curl = curl_easy_init();
  if(curl) {
    struct curl_slist *headers = NULL;
    struct curl_slist *recipients = NULL;
    struct curl_slist *slist = NULL;
    curl_mime *mime;
    curl_mime *alt;
    curl_mimepart *part;
    const char **cpp;

    /* This is the URL for your mailserver */
    curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com");

    /* Note that this option isn't strictly required, omitting it will result
     * in libcurl sending the MAIL FROM command with empty sender data. All
     * autoresponses should have an empty reverse-path, and should be directed
     * to the address in the reverse-path which triggered them. Otherwise,
     * they could cause an endless loop. See RFC 5321 Section 4.5.5 for more
     * details.
     */
    curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM);

    /* Add two recipients, in this particular case they correspond to the
     * To: and Cc: addressees in the header, but they could be any kind of
     * recipient. */
    recipients = curl_slist_append(recipients, TO);
    recipients = curl_slist_append(recipients, CC);
    curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);

    /* Build and set the message header list. */
    for(cpp = headers_text; *cpp; cpp++)
      headers = curl_slist_append(headers, *cpp);
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

    /* Build the mime message. */
    mime = curl_mime_init(curl);

    /* The inline part is an alternative proposing the html and the text
       versions of the e-mail. */
    alt = curl_mime_init(curl);

    /* HTML message. */
    part = curl_mime_addpart(alt);
    curl_mime_data(part, inline_html, CURL_ZERO_TERMINATED);
    curl_mime_type(part, "text/html");

    /* Text message. */
    part = curl_mime_addpart(alt);
    curl_mime_data(part, inline_text, CURL_ZERO_TERMINATED);

    /* Create the inline part. */
    part = curl_mime_addpart(mime);
    curl_mime_subparts(part, alt);
    curl_mime_type(part, "multipart/alternative");
    slist = curl_slist_append(NULL, "Content-Disposition: inline");
    curl_mime_headers(part, slist, 1);

    /* Add the current source program as an attachment. */
    part = curl_mime_addpart(mime);
    curl_mime_filedata(part, "smtp-mime.c");
    curl_easy_setopt(curl, CURLOPT_MIMEPOST, mime);

    /* Send the message */
    res = curl_easy_perform(curl);

    /* Check for errors */
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s\n",
              curl_easy_strerror(res));

    /* Free lists. */
    curl_slist_free_all(recipients);
    curl_slist_free_all(headers);

    /* curl won't send the QUIT command until you call cleanup, so you should
     * be able to re-use this connection for additional messages (setting
     * CURLOPT_MAIL_FROM and CURLOPT_MAIL_RCPT as required, and calling
     * curl_easy_perform() again. It may not be a good idea to keep the
     * connection open for a very long time though (more than a few minutes
     * may result in the server timing out the connection), and you do want to
     * clean up in the end.
     */
    curl_easy_cleanup(curl);

    /* Free multipart message. */
    curl_mime_free(mime);
  }

  return (int)res;
}