@@ -2388,12 +2388,14 @@ REFTABLE_OBJS += reftable/block.o
REFTABLE_OBJS += reftable/blocksource.o
REFTABLE_OBJS += reftable/publicbasics.o
REFTABLE_OBJS += reftable/record.o
+REFTABLE_OBJS += reftable/tree.o
REFTABLE_OBJS += reftable/zlib-compat.o
+REFTABLE_TEST_OBJS += reftable/basics_test.o
REFTABLE_TEST_OBJS += reftable/block_test.o
REFTABLE_TEST_OBJS += reftable/record_test.o
REFTABLE_TEST_OBJS += reftable/test_framework.o
-REFTABLE_TEST_OBJS += reftable/basics_test.o
+REFTABLE_TEST_OBJS += reftable/tree_test.o
TEST_OBJS := $(patsubst %$X,%.o,$(TEST_PROGRAMS)) $(patsubst %,t/helper/%,$(TEST_BUILTINS_OBJS))
OBJECTS := $(LIB_OBJS) $(BUILTIN_OBJS) $(PROGRAM_OBJS) $(TEST_OBJS) \
new file mode 100644
@@ -0,0 +1,63 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "tree.h"
+
+#include "basics.h"
+#include "system.h"
+
+struct tree_node *tree_search(void *key, struct tree_node **rootp,
+ int (*compare)(const void *, const void *),
+ int insert)
+{
+ int res;
+ if (*rootp == NULL) {
+ if (!insert) {
+ return NULL;
+ } else {
+ struct tree_node *n =
+ reftable_calloc(sizeof(struct tree_node));
+ n->key = key;
+ *rootp = n;
+ return *rootp;
+ }
+ }
+
+ res = compare(key, (*rootp)->key);
+ if (res < 0)
+ return tree_search(key, &(*rootp)->left, compare, insert);
+ else if (res > 0)
+ return tree_search(key, &(*rootp)->right, compare, insert);
+ return *rootp;
+}
+
+void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
+ void *arg)
+{
+ if (t->left != NULL) {
+ infix_walk(t->left, action, arg);
+ }
+ action(arg, t->key);
+ if (t->right != NULL) {
+ infix_walk(t->right, action, arg);
+ }
+}
+
+void tree_free(struct tree_node *t)
+{
+ if (t == NULL) {
+ return;
+ }
+ if (t->left != NULL) {
+ tree_free(t->left);
+ }
+ if (t->right != NULL) {
+ tree_free(t->right);
+ }
+ reftable_free(t);
+}
new file mode 100644
@@ -0,0 +1,34 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef TREE_H
+#define TREE_H
+
+/* tree_node is a generic binary search tree. */
+struct tree_node {
+ void *key;
+ struct tree_node *left, *right;
+};
+
+/* looks for `key` in `rootp` using `compare` as comparison function. If insert
+ * is set, insert the key if it's not found. Else, return NULL.
+ */
+struct tree_node *tree_search(void *key, struct tree_node **rootp,
+ int (*compare)(const void *, const void *),
+ int insert);
+
+/* performs an infix walk of the tree. */
+void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
+ void *arg);
+
+/*
+ * deallocates the tree nodes recursively. Keys should be deallocated separately
+ * by walking over the tree. */
+void tree_free(struct tree_node *t);
+
+#endif
new file mode 100644
@@ -0,0 +1,61 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#include "tree.h"
+
+#include "basics.h"
+#include "record.h"
+#include "test_framework.h"
+#include "reftable-tests.h"
+
+static int test_compare(const void *a, const void *b)
+{
+ return (char *)a - (char *)b;
+}
+
+struct curry {
+ void *last;
+};
+
+static void check_increasing(void *arg, void *key)
+{
+ struct curry *c = (struct curry *)arg;
+ if (c->last != NULL) {
+ assert(test_compare(c->last, key) < 0);
+ }
+ c->last = key;
+}
+
+static void test_tree(void)
+{
+ struct tree_node *root = NULL;
+
+ void *values[11] = { NULL };
+ struct tree_node *nodes[11] = { NULL };
+ int i = 1;
+ struct curry c = { NULL };
+ do {
+ nodes[i] = tree_search(values + i, &root, &test_compare, 1);
+ i = (i * 7) % 11;
+ } while (i != 1);
+
+ for (i = 1; i < ARRAY_SIZE(nodes); i++) {
+ assert(values + i == nodes[i]->key);
+ assert(nodes[i] ==
+ tree_search(values + i, &root, &test_compare, 0));
+ }
+
+ infix_walk(root, check_increasing, &c);
+ tree_free(root);
+}
+
+int tree_test_main(int argc, const char *argv[])
+{
+ RUN_TEST(test_tree);
+ return 0;
+}
@@ -6,5 +6,6 @@ int cmd__reftable(int argc, const char **argv)
basics_test_main(argc, argv);
block_test_main(argc, argv);
record_test_main(argc, argv);
+ tree_test_main(argc, argv);
return 0;
}