[PATCH 6/7] lib/database: index user headers.

[David Bremner]

There is a O(log(#user headers)) penalty for the second lookup of the
prefix name.
---
 lib/database.cc          |  6 ++++++
 lib/index.cc             | 28 ++++++++++++++++++++++++++++
 lib/notmuch-private.h    |  5 +++++
 test/T730-user-header.sh | 17 +++++++++++++++++
 4 files changed, 56 insertions(+)

diff --git a/lib/database.cc b/lib/database.cc
index 19aff0e8..2219a76a 100644
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -308,6 +308,12 @@ _setup_query_field_default (const prefix_t *prefix, notmuch_database_t *notmuch)
 	notmuch->query_parser->add_boolean_prefix (prefix->name, prefix->prefix);
 }
 
+notmuch_string_map_iterator_t *
+_notmuch_database_user_headers (notmuch_database_t *notmuch)
+{
+    return _notmuch_string_map_iterator_create (notmuch->user_header, "", false);
+}
+
 const char *
 _user_prefix (void *ctx, const char* name)
 {
diff --git a/lib/index.cc b/lib/index.cc
index efd9da4c..ef3369fd 100644
--- a/lib/index.cc
+++ b/lib/index.cc
@@ -595,6 +595,32 @@ _index_encrypted_mime_part (notmuch_message_t *message,
 
 }
 
+static notmuch_status_t
+_notmuch_message_index_user_headers (notmuch_message_t *message, GMimeMessage *mime_message)
+{
+
+    notmuch_database_t *notmuch = notmuch_message_get_database (message);
+    notmuch_string_map_iterator_t *iter = _notmuch_database_user_headers (notmuch);
+
+    for (; _notmuch_string_map_iterator_valid (iter);
+	 _notmuch_string_map_iterator_move_to_next (iter)) {
+
+	const char *prefix_name = _notmuch_string_map_iterator_key (iter);
+
+	const char *header_name = _notmuch_string_map_iterator_value (iter);
+
+	const char *header = g_mime_object_get_header (GMIME_OBJECT (mime_message), header_name);
+	if (header)
+	    _notmuch_message_gen_terms (message, prefix_name, header);
+    }
+
+    if (iter)
+	_notmuch_string_map_iterator_destroy (iter);
+    return NOTMUCH_STATUS_SUCCESS;
+
+}
+
+
 notmuch_status_t
 _notmuch_message_index_file (notmuch_message_t *message,
 			     notmuch_indexopts_t *indexopts,
@@ -625,6 +651,8 @@ _notmuch_message_index_file (notmuch_message_t *message,
     subject = g_mime_message_get_subject (mime_message);
     _notmuch_message_gen_terms (message, "subject", subject);
 
+    status = _notmuch_message_index_user_headers (message, mime_message);
+
     _index_mime_part (message, indexopts, g_mime_message_get_mime_part (mime_message));
 
     return NOTMUCH_STATUS_SUCCESS;
diff --git a/lib/notmuch-private.h b/lib/notmuch-private.h
index cf08411e..e46df9a8 100644
--- a/lib/notmuch-private.h
+++ b/lib/notmuch-private.h
@@ -652,6 +652,11 @@ _notmuch_string_map_iterator_value (notmuch_string_map_iterator_t *iterator);
 void
 _notmuch_string_map_iterator_destroy (notmuch_string_map_iterator_t *iterator);
 
+/* Create an iterator for user headers. Destroy with
+ * _notmuch_string_map_iterator_destroy. Actually in database.cc*/
+notmuch_string_map_iterator_t *
+_notmuch_database_user_headers (notmuch_database_t *notmuch);
+
 /* tags.c */
 
 notmuch_tags_t *
diff --git a/test/T730-user-header.sh b/test/T730-user-header.sh
index 1531f1d6..c08985b9 100755
--- a/test/T730-user-header.sh
+++ b/test/T730-user-header.sh
@@ -56,4 +56,21 @@ Query((Tmail AND (XUlist:notmuchmail at 1 PHRASE 2 XUlist:org at 2)))
 EOF
 test_expect_equal_file EXPECTED OUTPUT
 
+test_begin_subtest "index user header"
+notmuch config set index.header.list "List-Id"
+notmuch reindex '*'
+notmuch search --output=files list:notmuch | notmuch_search_files_sanitize | sort > OUTPUT
+cat <<EOF > EXPECTED
+MAIL_DIR/bar/baz/05:2,
+MAIL_DIR/bar/baz/23:2,
+MAIL_DIR/bar/baz/24:2,
+MAIL_DIR/bar/cur/20:2,
+MAIL_DIR/bar/new/21:2,
+MAIL_DIR/bar/new/22:2,
+MAIL_DIR/foo/cur/08:2,
+MAIL_DIR/foo/new/03:2,
+MAIL_DIR/new/04:2,
+EOF
+test_expect_equal_file EXPECTED OUTPUT
+
 test_done
-- 
2.20.1