X-Git-Url: https://git.notmuchmail.org/git?p=notmuch;a=blobdiff_plain;f=notmuch-reply.c;h=98f6442fb14f2ffc61a7650b1db9ab3afdc2f475;hp=3ec303455693d68764bf0ea4845519126a518918;hb=069cb5a73ac2487930baa75a9cd2850968361a16;hpb=fb50f31048272c6b055f9e1bb049fcf18a92310e

diff --git a/notmuch-reply.c b/notmuch-reply.c
index 3ec30345..98f6442f 100644
--- a/notmuch-reply.c
+++ b/notmuch-reply.c
@@ -188,6 +188,42 @@ add_recipients_for_string (GMimeMessage *message,
     return add_recipients_for_address_list (message, config, type, list);
 }
 
+/* Does the address in the Reply-To header of 'message' already appear
+ * in either the 'To' or 'Cc' header of the message?
+ */
+static int
+reply_to_header_is_redundant (notmuch_message_t *message)
+{
+    const char *header, *addr;
+    InternetAddressList *list;
+    InternetAddress *address;
+    InternetAddressMailbox *mailbox;
+
+    header = notmuch_message_get_header (message, "reply-to");
+    if (*header == '\0')
+	return 0;
+
+    list = internet_address_list_parse_string (header);
+
+    if (internet_address_list_length (list) != 1)
+	return 0;
+
+    address = internet_address_list_get_address (list, 0);
+    if (INTERNET_ADDRESS_IS_GROUP (address))
+	return 0;
+
+    mailbox = INTERNET_ADDRESS_MAILBOX (address);
+    addr = internet_address_mailbox_get_addr (mailbox);
+
+    if (strstr (notmuch_message_get_header (message, "to"), addr) != 0 ||
+	strstr (notmuch_message_get_header (message, "cc"), addr) != 0)
+    {
+	return 1;
+    }
+
+    return 0;
+}
+
 /* Augments the recipients of reply from the headers of message.
  *
  * If any of the user's addresses were found in these headers, the first
@@ -198,7 +234,7 @@ add_recipients_from_message (GMimeMessage *reply,
 			     notmuch_config_t *config,
 			     notmuch_message_t *message)
 {
-    static const struct {
+    struct {
 	const char *header;
 	const char *fallback;
 	GMimeRecipientType recipient_type;
@@ -211,6 +247,22 @@ add_recipients_from_message (GMimeMessage *reply,
     const char *from_addr = NULL;
     unsigned int i;
 
+    /* Some mailing lists munge the Reply-To header despite it being A Bad
+     * Thing, see http://www.unicom.com/pw/reply-to-harmful.html
+     *
+     * The munging is easy to detect, because it results in a
+     * redundant reply-to header, (with an address that already exists
+     * in either To or Cc). So in this case, we ignore the Reply-To
+     * field and use the From header. Thie ensures the original sender
+     * will get the reply even if not subscribed to the list. Note
+     * that the address in the Reply-To header will always appear in
+     * the reply.
+     */
+    if (reply_to_header_is_redundant (message)) {
+	reply_to_map[0].header = "from";
+	reply_to_map[0].fallback = NULL;
+    }
+
     for (i = 0; i < ARRAY_SIZE (reply_to_map); i++) {
 	const char *addr, *recipients;
 
@@ -226,6 +278,7 @@ add_recipients_from_message (GMimeMessage *reply,
 	if (from_addr == NULL)
 	    from_addr = addr;
     }
+
     return from_addr;
 }