Add a type to map names to short identifiers

We'll be using this for four kinds of identifier in dispatch.c

1 files changed, 34 insertions, 0 deletions

diff --git a/src/lib/container/namemap_st.h b/src/lib/container/namemap_st.h
new file mode 100644
index 0000000000..5717352fa2
--- /dev/null
+++ b/src/lib/container/namemap_st.h
@@ -0,0 +1,34 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef NAMEMAP_ST_H
+#define NAMEMAP_ST_H
+
+#include "lib/cc/compat_compiler.h"
+#include "ext/ht.h"
+
+struct smartlist_t;
+
+/** Longest allowed name that's allowed in a namemap_t. */
+#define MAX_NAMEMAP_NAME_LEN 128
+
+/** An entry inside a namemap_t. Maps a string to a numeric identifier. */
+typedef struct mapped_name_t {
+  HT_ENTRY(mapped_name_t) node;
+  unsigned intval;
+  char name[FLEXIBLE_ARRAY_MEMBER];
+} mapped_name_t;
+
+/** A structure that allocates small numeric identifiers for names and maps
+ * back and forth between them.  */
+struct namemap_t {
+  HT_HEAD(namemap_ht, mapped_name_t) ht;
+  struct smartlist_t *names;
+};
+
+/** Macro to initialize a namemap. */
+#define NAMEMAP_INIT() { HT_INITIALIZER(), NULL }
+
+#endif