notmuch-reply.c: implement notmuch_reply_format_headers_only

This command only generates References, To, and Cc headers.
The purpose is primarily for use in

  git send-email --notmuch id:<MESSAGE-ID>

to get proper threading and address the relevant parties.  Hooks for
other SCMs may come later.

Signed-off-by: Jed Brown <jed@59A2.org>

diff --git a/notmuch-reply.c b/notmuch-reply.c
index 17eb38d95f92d69531f38cca55a89ca271715ef0..e85568c082ef8d519c1e391221e29867fc02d2aa 100644 (file)
--- a/notmuch-reply.c
+++ b/notmuch-reply.c
@@ -283,6 +283,74 @@ notmuch_reply_format_default(void *ctx, notmuch_config_t *config, notmuch_query_
     return 0;
 }
 
+/* This format is currently tuned for a git send-email --notmuch hook */
+static int
+notmuch_reply_format_headers_only(void *ctx, notmuch_config_t *config, notmuch_query_t *query)
+{
+    GMimeMessage *reply;
+    notmuch_messages_t *messages;
+    notmuch_message_t *message;
+    const char *recipients, *in_reply_to, *orig_references, *references;
+    char *reply_headers;
+    unsigned int i;
+
+    for (messages = notmuch_query_search_messages (query);
+        notmuch_messages_has_more (messages);
+        notmuch_messages_advance (messages))
+    {
+       message = notmuch_messages_get (messages);
+
+       /* The 0 means we do not want headers in a "pretty" order. */
+       reply = g_mime_message_new (0);
+       if (reply == NULL) {
+           fprintf (stderr, "Out of memory\n");
+           return 1;
+       }
+
+       in_reply_to = talloc_asprintf (ctx, "<%s>",
+                            notmuch_message_get_message_id (message));
+
+       orig_references = notmuch_message_get_header (message, "references");
+
+       /* We print References first because git format-patch treats it specially.
+        * Git uses the first entry of References to create In-Reply-To.
+        */
+       references = talloc_asprintf (ctx, "%s%s%s",
+                                     in_reply_to,
+                                     orig_references ? orig_references : "",
+                                     orig_references ? " " : "");
+       g_mime_object_set_header (GMIME_OBJECT (reply),
+                                 "References", references);
+
+       for (i = 0; i < ARRAY_SIZE (reply_to_map); i++) {
+           const char *addr;
+
+           recipients = notmuch_message_get_header (message,
+                                                    reply_to_map[i].header);
+           if ((recipients == NULL || recipients[0] == '\0') && reply_to_map[i].fallback)
+               recipients = notmuch_message_get_header (message,
+                                                        reply_to_map[i].fallback);
+
+           addr = add_recipients_for_string (reply, config,
+                                             reply_to_map[i].recipient_type,
+                                             recipients);
+       }
+
+       g_mime_object_set_header (GMIME_OBJECT (reply), "Bcc",
+                          notmuch_config_get_user_primary_email (config));
+
+       reply_headers = g_mime_object_to_string (GMIME_OBJECT (reply));
+       printf ("%s", reply_headers);
+       free (reply_headers);
+
+       g_object_unref (G_OBJECT (reply));
+       reply = NULL;
+
+       notmuch_message_destroy (message);
+    }
+    return 0;
+}
+
 int
 notmuch_reply_command (void *ctx, int argc, char *argv[])
 {
@@ -304,6 +372,8 @@ notmuch_reply_command (void *ctx, int argc, char *argv[])
            opt = argv[i] + sizeof ("--format=") - 1;
            if (strcmp (opt, "default") == 0) {
                reply_format_func = notmuch_reply_format_default;
+           } else if (strcmp (opt, "headers-only") == 0) {
+               reply_format_func = notmuch_reply_format_headers_only;
            } else {
                fprintf (stderr, "Invalid value for --format: %s\n", opt);
                return 1;