diff -r 000000000000 -r 6474c204b198 js/jsd/jshash.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/jsd/jshash.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,118 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jshash_h___
+#define jshash_h___
+
+/*
+ * API to portable hash table code.
+ */
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+extern "C" {
+
+typedef uint32_t JSHashNumber;
+typedef struct JSHashEntry JSHashEntry;
+typedef struct JSHashTable JSHashTable;
+
+#define JS_HASH_BITS 32
+#define JS_GOLDEN_RATIO 0x9E3779B9U
+
+typedef JSHashNumber (* JSHashFunction)(const void *key);
+typedef int (* JSHashComparator)(const void *v1, const void *v2);
+typedef int (* JSHashEnumerator)(JSHashEntry *he, int i, void *arg);
+
+/* Flag bits in JSHashEnumerator's return value */
+#define HT_ENUMERATE_NEXT       0       /* continue enumerating entries */
+#define HT_ENUMERATE_STOP       1       /* stop enumerating entries */
+#define HT_ENUMERATE_REMOVE     2       /* remove and free the current entry */
+
+typedef struct JSHashAllocOps {
+    void *              (*allocTable)(void *pool, size_t size);
+    void                (*freeTable)(void *pool, void *item, size_t size);
+    JSHashEntry *       (*allocEntry)(void *pool, const void *key);
+    void                (*freeEntry)(void *pool, JSHashEntry *he, unsigned flag);
+} JSHashAllocOps;
+
+#define HT_FREE_VALUE   0               /* just free the entry's value */
+#define HT_FREE_ENTRY   1               /* free value and entire entry */
+
+struct JSHashEntry {
+    JSHashEntry         *next;          /* hash chain linkage */
+    JSHashNumber        keyHash;        /* key hash function result */
+    const void          *key;           /* ptr to opaque key */
+    void                *value;         /* ptr to opaque value */
+};
+
+struct JSHashTable {
+    JSHashEntry         **buckets;      /* vector of hash buckets */
+    uint32_t            nentries;       /* number of entries in table */
+    uint32_t            shift;          /* multiplicative hash shift */
+    JSHashFunction      keyHash;        /* key hash function */
+    JSHashComparator    keyCompare;     /* key comparison function */
+    JSHashComparator    valueCompare;   /* value comparison function */
+    const JSHashAllocOps *allocOps;     /* allocation operations */
+    void                *allocPriv;     /* allocation private data */
+#ifdef JS_HASHMETER
+    uint32_t            nlookups;       /* total number of lookups */
+    uint32_t            nsteps;         /* number of hash chains traversed */
+    uint32_t            ngrows;         /* number of table expansions */
+    uint32_t            nshrinks;       /* number of table contractions */
+#endif
+};
+
+/*
+ * Create a new hash table.
+ * If allocOps is null, use default allocator ops built on top of malloc().
+ */
+extern JSHashTable * 
+JS_NewHashTable(uint32_t n, JSHashFunction keyHash,
+                JSHashComparator keyCompare, JSHashComparator valueCompare,
+                const JSHashAllocOps *allocOps, void *allocPriv);
+
+extern void
+JS_HashTableDestroy(JSHashTable *ht);
+
+/* Low level access methods */
+extern JSHashEntry **
+JS_HashTableRawLookup(JSHashTable *ht, JSHashNumber keyHash, const void *key);
+
+extern JSHashEntry *
+JS_HashTableRawAdd(JSHashTable *ht, JSHashEntry **&hep, JSHashNumber keyHash,
+                   const void *key, void *value);
+
+extern void
+JS_HashTableRawRemove(JSHashTable *ht, JSHashEntry **hep, JSHashEntry *he);
+
+/* Higher level access methods */
+extern JSHashEntry *
+JS_HashTableAdd(JSHashTable *ht, const void *key, void *value);
+
+extern bool
+JS_HashTableRemove(JSHashTable *ht, const void *key);
+
+extern int
+JS_HashTableEnumerateEntries(JSHashTable *ht, JSHashEnumerator f, void *arg);
+
+extern void *
+JS_HashTableLookup(JSHashTable *ht, const void *key);
+
+extern int
+JS_HashTableDump(JSHashTable *ht, JSHashEnumerator dump, FILE *fp);
+
+/* General-purpose C string hash function. */
+extern JSHashNumber
+JS_HashString(const void *key);
+
+/* Stub function just returns v1 == v2 */
+extern int
+JS_CompareValues(const void *v1, const void *v2);
+
+} // extern "C"
+
+#endif /* jshash_h___ */