Import notmuch_0.27.orig.tar.gz

[dgit import orig notmuch_0.27.orig.tar.gz]

1 files changed, 228 insertions, 0 deletions

diff --git a/lib/string-map.c b/lib/string-map.c
new file mode 100644
index 00000000..ad818207
--- /dev/null
+++ b/lib/string-map.c
@@ -0,0 +1,228 @@
+/* string-map.c - associative arrays of strings
+ *
+ *
+ * Copyright © 2016 David Bremner
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/ .
+ *
+ * Author: David Bremner <david@tethera.net>
+ */
+
+#include "notmuch-private.h"
+
+/* Create a new notmuch_string_map_t object, with 'ctx' as its
+ * talloc owner.
+ *
+ * This function can return NULL in case of out-of-memory.
+ */
+
+typedef struct _notmuch_string_pair_t {
+    char *key;
+    char *value;
+} notmuch_string_pair_t;
+
+struct _notmuch_string_map {
+    bool sorted;
+    size_t length;
+    notmuch_string_pair_t *pairs;
+};
+
+struct _notmuch_string_map_iterator {
+    notmuch_string_pair_t *current;
+    bool exact;
+    const char *key;
+};
+
+notmuch_string_map_t *
+_notmuch_string_map_create (const void *ctx)
+{
+    notmuch_string_map_t *map;
+
+    map = talloc (ctx, notmuch_string_map_t);
+    if (unlikely (map == NULL))
+	return NULL;
+
+    map->length = 0;
+    map->pairs = NULL;
+    map->sorted = true;
+
+    return map;
+}
+
+void
+_notmuch_string_map_append (notmuch_string_map_t *map,
+			    const char *key,
+			    const char *value)
+{
+
+    map->length++;
+    map->sorted = false;
+
+    if (map->pairs)
+	map->pairs = talloc_realloc (map, map->pairs, notmuch_string_pair_t, map->length + 1);
+    else
+	map->pairs = talloc_array (map, notmuch_string_pair_t, map->length + 1);
+
+    map->pairs[map->length - 1].key = talloc_strdup (map, key);
+    map->pairs[map->length - 1].value = talloc_strdup (map, value);
+
+    /* Add sentinel */
+    map->pairs[map->length].key = NULL;
+    map->pairs[map->length].value = NULL;
+
+}
+
+static int
+cmppair (const void *pa, const void *pb)
+{
+    notmuch_string_pair_t *a = (notmuch_string_pair_t *) pa;
+    notmuch_string_pair_t *b = (notmuch_string_pair_t *) pb;
+
+    return strcmp (a->key, b->key);
+}
+
+static void
+_notmuch_string_map_sort (notmuch_string_map_t *map)
+{
+    if (map->length == 0)
+	return;
+
+    if (map->sorted)
+	return;
+
+    qsort (map->pairs, map->length, sizeof (notmuch_string_pair_t), cmppair);
+
+    map->sorted = true;
+}
+
+static bool
+string_cmp (const char *a, const char *b, bool exact)
+{
+    if (exact)
+	return (strcmp (a, b));
+    else
+	return (strncmp (a, b, strlen (a)));
+}
+
+static notmuch_string_pair_t *
+bsearch_first (notmuch_string_pair_t *array, size_t len, const char *key, bool exact)
+{
+    size_t first = 0;
+    size_t last = len - 1;
+    size_t mid;
+
+    if (len <= 0)
+	return NULL;
+
+    while (last > first) {
+	mid = (first + last) / 2;
+	int sign = string_cmp (key, array[mid].key, exact);
+
+	if (sign <= 0)
+	    last = mid;
+	else
+	    first = mid + 1;
+    }
+
+
+    if (string_cmp (key, array[first].key, exact) == 0)
+	return array + first;
+    else
+	return NULL;
+
+}
+
+const char *
+_notmuch_string_map_get (notmuch_string_map_t *map, const char *key)
+{
+    notmuch_string_pair_t *pair;
+
+    /* this means that calling append invalidates iterators */
+    _notmuch_string_map_sort (map);
+
+    pair = bsearch_first (map->pairs, map->length, key, true);
+    if (! pair)
+	return NULL;
+
+    return pair->value;
+}
+
+notmuch_string_map_iterator_t *
+_notmuch_string_map_iterator_create (notmuch_string_map_t *map, const char *key,
+				     bool exact)
+{
+    notmuch_string_map_iterator_t *iter;
+
+    _notmuch_string_map_sort (map);
+
+    iter = talloc (map, notmuch_string_map_iterator_t);
+    if (unlikely (iter == NULL))
+	return NULL;
+
+    if (unlikely (talloc_reference (iter, map) == NULL))
+	return NULL;
+
+    iter->key = talloc_strdup (iter, key);
+    iter->exact = exact;
+    iter->current = bsearch_first (map->pairs, map->length, key, exact);
+    return iter;
+}
+
+bool
+_notmuch_string_map_iterator_valid (notmuch_string_map_iterator_t *iterator)
+{
+    if (iterator->current == NULL)
+	return false;
+
+    /* sentinel */
+    if (iterator->current->key == NULL)
+	return false;
+
+    return (0 == string_cmp (iterator->key, iterator->current->key, iterator->exact));
+
+}
+
+void
+_notmuch_string_map_iterator_move_to_next (notmuch_string_map_iterator_t *iterator)
+{
+
+    if (! _notmuch_string_map_iterator_valid (iterator))
+	return;
+
+    (iterator->current)++;
+}
+
+const char *
+_notmuch_string_map_iterator_key (notmuch_string_map_iterator_t *iterator)
+{
+    if (! _notmuch_string_map_iterator_valid (iterator))
+	return NULL;
+
+    return iterator->current->key;
+}
+
+const char *
+_notmuch_string_map_iterator_value (notmuch_string_map_iterator_t *iterator)
+{
+    if (! _notmuch_string_map_iterator_valid (iterator))
+	return NULL;
+
+    return iterator->current->value;
+}
+
+void
+_notmuch_string_map_iterator_destroy (notmuch_string_map_iterator_t *iterator)
+{
+    talloc_free (iterator);
+}