1 files changed, 84 insertions, 0 deletions
diff --git a/lib/trace-cmd/trace-hash.c b/lib/trace-cmd/trace-hash.c
new file mode 100644
index 00000000..bed97323
--- /dev/null
+++ b/lib/trace-cmd/trace-hash.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2014, Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <errno.h>
+
+#include "trace-cmd-private.h"
+#include "trace-hash.h"
+
+int __hidden trace_hash_init(struct trace_hash *hash, int buckets)
+{
+	memset(hash, 0, sizeof(*hash));
+
+	hash->buckets = calloc(sizeof(*hash->buckets), buckets);
+	if (!hash->buckets)
+		return -ENOMEM;
+	hash->nr_buckets = buckets;
+
+	/* If a power of two then we can shortcut */
+	if (!(buckets & (buckets - 1)))
+		hash->power = buckets - 1;
+
+	return 0;
+}
+
+void __hidden trace_hash_free(struct trace_hash *hash)
+{
+	free(hash->buckets);
+}
+
+int __hidden trace_hash_empty(struct trace_hash *hash)
+{
+	struct trace_hash_item **bucket;
+
+	trace_hash_for_each_bucket(bucket, hash)
+		if (*bucket)
+			return 0;
+	return 1;
+}
+
+int __hidden trace_hash_add(struct trace_hash *hash, struct trace_hash_item *item)
+{
+	struct trace_hash_item *next;
+	int bucket = hash->power ? item->key & hash->power :
+		item->key % hash->nr_buckets;
+
+	if (hash->buckets[bucket]) {
+		next = hash->buckets[bucket];
+		next->prev = item;
+	} else
+		next = NULL;
+
+	item->next = next;
+	item->prev = (struct trace_hash_item *)&hash->buckets[bucket];
+
+	hash->buckets[bucket] = item;
+
+	return 1;
+}
+
+ __hidden struct trace_hash_item *
+trace_hash_find(struct trace_hash *hash, unsigned long long key,
+		trace_hash_func match, void *data)
+{
+	struct trace_hash_item *item;
+	int bucket = hash->power ? key & hash->power :
+		key % hash->nr_buckets;
+
+	for (item = hash->buckets[bucket]; item; item = item->next) {
+		if (item->key == key) {
+			if (!match)
+				return item;
+			if (match(item, data))
+				return item;
+		}
+	}
+
+	return NULL;
+}