lib/config: add config_pairs iterators

The layer of shims here seems a bit wasteful compared to just calling
the corresponding string map functions directly, but it allows control
over the API (calling with notmuch_database_t *) and flexibility for
future changes.

2 files changed, 120 insertions, 0 deletions

diff --git a/lib/config.cc b/lib/config.cc
index 24418f98..ab45ae7b 100644
--- a/lib/config.cc
+++ b/lib/config.cc
@@ -38,6 +38,10 @@ struct _notmuch_config_values {
     void *children; /* talloc_context */
 };
 
+struct _notmuch_config_pairs {
+    notmuch_string_map_iterator_t *iter;
+};
+
 static const char *_notmuch_config_key_to_string (notmuch_config_key_t key);
 
 static int
@@ -339,6 +343,47 @@ notmuch_config_values_destroy (notmuch_config_values_t *values)
     talloc_free (values);
 }
 
+notmuch_config_pairs_t *
+notmuch_config_get_pairs (notmuch_database_t *notmuch,
+			  const char *prefix)
+{
+    notmuch_config_pairs_t *pairs = talloc (notmuch, notmuch_config_pairs_t);
+
+    pairs->iter = _notmuch_string_map_iterator_create (notmuch->config, prefix, false);
+    return pairs;
+}
+
+notmuch_bool_t
+notmuch_config_pairs_valid (notmuch_config_pairs_t *pairs)
+{
+    return _notmuch_string_map_iterator_valid (pairs->iter);
+}
+
+void
+notmuch_config_pairs_move_to_next (notmuch_config_pairs_t *pairs)
+{
+    _notmuch_string_map_iterator_move_to_next (pairs->iter);
+}
+
+const char *
+notmuch_config_pairs_key (notmuch_config_pairs_t *pairs)
+{
+    return _notmuch_string_map_iterator_key (pairs->iter);
+}
+
+const char *
+notmuch_config_pairs_value (notmuch_config_pairs_t *pairs)
+{
+    return _notmuch_string_map_iterator_value (pairs->iter);
+}
+
+void
+notmuch_config_pairs_destroy (notmuch_config_pairs_t *pairs)
+{
+    _notmuch_string_map_iterator_destroy (pairs->iter);
+    talloc_free (pairs);
+}
+
 notmuch_status_t
 _notmuch_config_load_from_file (notmuch_database_t *notmuch,
 				GKeyFile *file)
diff --git a/lib/notmuch.h b/lib/notmuch.h
index dd3d06a1..2a013be0 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -245,6 +245,7 @@ typedef struct _notmuch_directory notmuch_directory_t;
 typedef struct _notmuch_filenames notmuch_filenames_t;
 typedef struct _notmuch_config_list notmuch_config_list_t;
 typedef struct _notmuch_config_values notmuch_config_values_t;
+typedef struct _notmuch_config_pairs notmuch_config_pairs_t;
 typedef struct _notmuch_indexopts notmuch_indexopts_t;
 #endif /* __DOXYGEN__ */
 
@@ -2639,6 +2640,80 @@ notmuch_config_values_start (notmuch_config_values_t *values);
 void
 notmuch_config_values_destroy (notmuch_config_values_t *values);
 
+
+/**
+ * Returns an iterator for a (key, value) configuration pairs
+ *
+ * @param[in] notmuch database
+ * @param[in] prefix prefix for keys. Pass "" for all keys.
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ *
+ * @retval NULL in case of error.
+ */
+notmuch_config_pairs_t *
+notmuch_config_get_pairs (notmuch_database_t *notmuch,
+			  const char *prefix);
+
+/**
+ * Is the given 'config_pairs' iterator pointing at a valid element.
+ *
+ * @param[in] pairs iterator
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ *
+ * @retval FALSE if passed a NULL pointer, or the iterator is exhausted.
+ *
+ */
+notmuch_bool_t
+notmuch_config_pairs_valid (notmuch_config_pairs_t *pairs);
+
+/**
+ * Move the 'config_pairs' iterator to the next element
+ *
+ * @param[in,out] pairs iterator
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ *
+ */
+void
+notmuch_config_pairs_move_to_next (notmuch_config_pairs_t *pairs);
+
+/**
+ * Get the current key from the 'config_pairs' iterator
+ *
+ * @param[in] pairs iterator
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ *
+ * @retval a string with the same lifetime as the iterator
+ */
+const char *
+notmuch_config_pairs_key (notmuch_config_pairs_t *pairs);
+
+/**
+ * Get the current value from the 'config_pairs' iterator
+ *
+ * @param[in] pairs iterator
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ *
+ * @retval a string with the same lifetime as the iterator
+ */
+const char *
+notmuch_config_pairs_value (notmuch_config_pairs_t *pairs);
+
+/**
+ * Destroy a config_pairs iterator, along with any associated
+ * resources.
+ *
+ * @param[in,out] pairs iterator
+ *
+ * @since libnotmuch 5.4 (notmuch 0.32)
+ */
+void
+notmuch_config_pairs_destroy (notmuch_config_pairs_t *pairs);
+
 /**
  * get a configuration value from an open database as Boolean
  *