1 files changed, 61 insertions, 0 deletions
diff --git a/gdb/filename-seen-cache.h b/gdb/filename-seen-cache.h
new file mode 100644
index 0000000..549effd
--- /dev/null
+++ b/gdb/filename-seen-cache.h
@@ -0,0 +1,61 @@
+/* Filename-seen cache for the GNU debugger, GDB.
+
+   Copyright (C) 1986-2017 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   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 <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "common/function-view.h"
+
+/* Cache to watch for file names already seen.  */
+
+class filename_seen_cache
+{
+public:
+  filename_seen_cache ();
+  ~filename_seen_cache ();
+
+  DISABLE_COPY_AND_ASSIGN (filename_seen_cache);
+
+  /* Empty the cache, but do not delete it.  */
+  void clear ();
+
+  /* If FILE is not already in the table of files in CACHE, add it and
+     return false; otherwise return true.
+
+     NOTE: We don't manage space for FILE, we assume FILE lives as
+     long as the caller needs.  */
+  bool seen (const char *file);
+
+  /* Traverse all cache entries, calling CALLBACK on each.  The
+     filename is passed as argument to CALLBACK.  */
+  void traverse (gdb::function_view<void (const char *filename)> callback)
+  {
+    auto erased_cb = [] (void **slot, void *info) -> int
+      {
+	auto filename = (const char *) *slot;
+	auto restored_cb = (decltype (callback) *) info;
+	(*restored_cb) (filename);
+	return 1;
+      };
+
+    htab_traverse_noresize (m_tab, erased_cb, &callback);
+  }
+
+private:
+  /* Table of files seen so far.  */
+  htab_t m_tab;
+};