1 files changed, 97 insertions, 85 deletions

diff --git a/docs/examples/smtp-multi.c b/docs/examples/smtp-multi.c
index 6462aff2..7f3d333d 100644
--- a/docs/examples/smtp-multi.c
+++ b/docs/examples/smtp-multi.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2014, 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
@@ -19,139 +19,151 @@
  * KIND, either express or implied.
  *
  ***************************************************************************/
-/* This is an example application source code sending SMTP mail using the
- * multi interface.
- */
-
 #include <string.h>
 #include <curl/curl.h>
 
-/*
- * This is the list of basic details you need to tweak to get things right.
+/* This is an example showing how to send mail using libcurl's SMTP
+ * capabilities. It builds on the smtp-mail.c example to demonstrate how to use
+ * libcurl's multi interface.
+ *
+ * Note that this example requires libcurl 7.20.0 or above.
  */
-#define USERNAME "user@example.com"
-#define PASSWORD "123qwerty"
-#define SMTPSERVER "smtp.example.com"
-#define SMTPPORT ":587" /* it is a colon+port string, but you can set it
-                           to "" to use the default port */
-#define RECIPIENT "<recipient@example.com>"
-#define MAILFROM "<realuser@example.com>"
+
+#define FROM     "<sender@example.com>"
+#define TO       "<recipient@example.com>"
+#define CC       "<info@example.com>"
 
 #define MULTI_PERFORM_HANG_TIMEOUT 60 * 1000
 
-/* Note that you should include the actual meta data headers here as well if
-   you want the mail to have a Subject, another From:, show a To: or whatever
-   you think your mail should feature! */
-static const char *text[]={
-  "one\n",
-  "two\n",
-  "three\n",
-  " Hello, this is CURL email SMTP\n",
+static const char *payload_text[] = {
+  "Date: Mon, 29 Nov 2010 21:54:29 +1100\r\n",
+  "To: " TO "\r\n",
+  "From: " FROM "(Example User)\r\n",
+  "Cc: " CC "(Another example User)\r\n",
+  "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@rfcpedant.example.org>\r\n",
+  "Subject: SMTP multi example message\r\n",
+  "\r\n", /* empty line to divide headers from body, see RFC5322 */
+  "The body of the message starts here.\r\n",
+  "\r\n",
+  "It could be a lot of lines, could be MIME encoded, whatever.\r\n",
+  "Check RFC5322.\r\n",
   NULL
 };
 
-struct WriteThis {
-  int counter;
+struct upload_status {
+  int lines_read;
 };
 
-static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
+static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
 {
-  struct WriteThis *pooh = (struct WriteThis *)userp;
+  struct upload_status *upload_ctx = (struct upload_status *)userp;
   const char *data;
 
-  if(size*nmemb < 1)
+  if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) {
     return 0;
+  }
 
-  data = text[pooh->counter];
+  data = payload_text[upload_ctx->lines_read];
 
   if(data) {
     size_t len = strlen(data);
     memcpy(ptr, data, len);
-    pooh->counter++; /* advance pointer */
+    upload_ctx->lines_read++;
+
     return len;
   }
-  return 0;                         /* no more data left to deliver */
+
+  return 0;
 }
 
 static struct timeval tvnow(void)
 {
-  /*
-  ** time() returns the value of time in seconds since the Epoch.
-  */
   struct timeval now;
+
+  /* time() returns the value of time in seconds since the epoch */
   now.tv_sec = (long)time(NULL);
   now.tv_usec = 0;
+
   return now;
 }
 
 static long tvdiff(struct timeval newer, struct timeval older)
 {
-  return (newer.tv_sec-older.tv_sec)*1000+
-    (newer.tv_usec-older.tv_usec)/1000;
+  return (newer.tv_sec - older.tv_sec) * 1000 +
+    (newer.tv_usec - older.tv_usec) / 1000;
 }
 
 int main(void)
 {
-   CURL *curl;
-   CURLM *mcurl;
-   int still_running = 1;
-   struct timeval mp_start;
-   struct WriteThis pooh;
-   struct curl_slist* rcpt_list = NULL;
+  CURL *curl;
+  CURLM *mcurl;
+  int still_running = 1;
+  struct timeval mp_start;
+  struct curl_slist *recipients = NULL;
+  struct upload_status upload_ctx;
+
+  upload_ctx.lines_read = 0;
 
-   pooh.counter = 0;
+  curl_global_init(CURL_GLOBAL_DEFAULT);
 
-   curl_global_init(CURL_GLOBAL_DEFAULT);
+  curl = curl_easy_init();
+  if(!curl)
+    return 1;
 
-   curl = curl_easy_init();
-   if(!curl)
-     return 1;
+  mcurl = curl_multi_init();
+  if(!mcurl)
+    return 2;
 
-   mcurl = curl_multi_init();
-   if(!mcurl)
-     return 2;
+  /* This is the URL for your mailserver */
+  curl_easy_setopt(curl, CURLOPT_URL, "smtp://mail.example.com");
 
-   rcpt_list = curl_slist_append(rcpt_list, RECIPIENT);
-   /* more addresses can be added here
-      rcpt_list = curl_slist_append(rcpt_list, "<others@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);
 
-   curl_easy_setopt(curl, CURLOPT_URL, "smtp://" SMTPSERVER SMTPPORT);
-   curl_easy_setopt(curl, CURLOPT_USERNAME, USERNAME);
-   curl_easy_setopt(curl, CURLOPT_PASSWORD, PASSWORD);
-   curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
-   curl_easy_setopt(curl, CURLOPT_MAIL_FROM, MAILFROM);
-   curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, rcpt_list);
-   curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_ALL);
-   curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
-   curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
-   curl_easy_setopt(curl, CURLOPT_READDATA, &pooh);
-   curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
-   curl_easy_setopt(curl, CURLOPT_SSLVERSION, 0L);
-   curl_easy_setopt(curl, CURLOPT_SSL_SESSIONID_CACHE, 0L);
-   curl_multi_add_handle(mcurl, curl);
-
-   mp_start = tvnow();
-
-  /* we start some action by calling perform right away */
+  /* 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);
+
+  /* We're using a callback function to specify the payload (the headers and
+   * body of the message). You could just use the CURLOPT_READDATA option to
+   * specify a FILE pointer to read from. */
+  curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source);
+  curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx);
+  curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
+
+  /* Tell the multi stack about our easy handle */
+  curl_multi_add_handle(mcurl, curl);
+
+  /* Record the start time which we can use later */
+  mp_start = tvnow();
+
+  /* We start some action by calling perform right away */
   curl_multi_perform(mcurl, &still_running);
 
   while(still_running) {
     struct timeval timeout;
-    int rc; /* select() return code */
-
     fd_set fdread;
     fd_set fdwrite;
     fd_set fdexcep;
     int maxfd = -1;
+    int rc;
 
     long curl_timeo = -1;
 
+    /* Initialise the file descriptors */
     FD_ZERO(&fdread);
     FD_ZERO(&fdwrite);
     FD_ZERO(&fdexcep);
 
-    /* set a suitable timeout to play around with */
+    /* Set a suitable timeout to play around with */
     timeout.tv_sec = 1;
     timeout.tv_usec = 0;
 
@@ -164,7 +176,7 @@ int main(void)
         timeout.tv_usec = (curl_timeo % 1000) * 1000;
     }
 
-    /* get file descriptors from the transfers */
+    /* Get file descriptors from the transfers */
     curl_multi_fdset(mcurl, &fdread, &fdwrite, &fdexcep, &maxfd);
 
     /* In a real-world program you OF COURSE check the return code of the
@@ -172,32 +184,32 @@ int main(void)
        greater or equal than -1.  We call select(maxfd + 1, ...), specially in
        case of (maxfd == -1), we call select(0, ...), which is basically equal
        to sleep. */
-
     rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
 
-    if (tvdiff(tvnow(), mp_start) > MULTI_PERFORM_HANG_TIMEOUT) {
-      fprintf(stderr, "ABORTING TEST, since it seems "
-              "that it would have run forever.\n");
+    if(tvdiff(tvnow(), mp_start) > MULTI_PERFORM_HANG_TIMEOUT) {
+      fprintf(stderr,
+              "ABORTING: Since it seems that we would have run forever.\n");
       break;
     }
 
     switch(rc) {
-    case -1:
-      /* select error */
+    case -1:  /* select error */
       break;
-    case 0: /* timeout */
-    default: /* action */
+    case 0:   /* timeout */
+    default:  /* action */
       curl_multi_perform(mcurl, &still_running);
       break;
     }
   }
 
-  curl_slist_free_all(rcpt_list);
+  /* Free the list of recipients */
+  curl_slist_free_all(recipients);
+
+  /* Always cleanup */
   curl_multi_remove_handle(mcurl, curl);
   curl_multi_cleanup(mcurl);
   curl_easy_cleanup(curl);
   curl_global_cleanup();
+
   return 0;
 }
-
-