1 files changed, 59 insertions, 0 deletions
diff --git a/epan/fifo_string_cache.h b/epan/fifo_string_cache.h
new file mode 100644
index 00000000..9f4fd407
--- /dev/null
+++ b/epan/fifo_string_cache.h
@@ -0,0 +1,59 @@
+/* fifo_string_cache.h
+ * A string cache, possibly with a bounded size, using FIFO order to control
+ * the size.
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef __FIFO_STRING_CACHE_H__
+#define __FIFO_STRING_CACHE_H__
+
+#include <glib.h>
+#include "ws_symbol_export.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+typedef struct {
+    GHashTable          *set;
+    GSList              *head;
+    GSList              *tail;
+    guint               max_entries;
+} fifo_string_cache_t;
+
+// These functions are marked with WS_DLL_PUBLIC so they can be unit-tested
+
+// Initialize an object. If string_free_func is given, then the
+// fifo_string_cache owns the string data, and will call this string_free_func
+// during fifo_string_cache_free().
+// If string_free_func is NULL, then the caller owns the string data, and it is
+// the caller that is responsible for freeing the data.
+WS_DLL_PUBLIC void
+fifo_string_cache_init(fifo_string_cache_t *fcache, guint max_entries, GDestroyNotify string_free_func);
+
+// Free all memory owned by the fifo_string_cache. Whether or not the
+// fifoe_string_cache owns the actual strings depends on whether a
+// string_free_func was passed in during fifo_string_cache_init().
+WS_DLL_PUBLIC void
+fifo_string_cache_free(fifo_string_cache_t *fcache);
+
+// Does the cache contain a specific string?
+WS_DLL_PUBLIC gboolean
+fifo_string_cache_contains(fifo_string_cache_t *fcache, const gchar *entry);
+
+// Insert a string. The return value indicates whether the string was already
+// in the cache before this function was called. If the string was newly
+// inserted, and max_entries is > 0, and inserting the string would have caused
+// max_entries to be exceeded, the oldest inserted key is removed (FIFO order).
+WS_DLL_PUBLIC gboolean
+fifo_string_cache_insert(fifo_string_cache_t *fcache, const gchar *entry);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* __FIFO_STRING_CACHE_H__ */