1 files changed, 79 insertions, 0 deletions
diff --git a/tools/build/src/engine/hash.h b/tools/build/src/engine/hash.h
new file mode 100644
index 000000000..7c40e8c4a
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+++ b/tools/build/src/engine/hash.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright 1993, 1995 Christopher Seiwald.
+ *
+ * This file is part of Jam - see jam.c for Copyright information.
+ */
+
+/*
+ * hash.h - simple in-memory hashing routines
+ */
+
+#ifndef BOOST_JAM_HASH_H
+#define BOOST_JAM_HASH_H
+
+#include "object.h"
+
+/*
+ * An opaque struct representing an item in the hash table. The first element of
+ * every struct stored in the table must be an OBJECT * which is treated as the
+ * key.
+ */
+typedef struct hashdata HASHDATA;
+
+/*
+ * hashinit() - initialize a hash table, returning a handle.
+ *
+ * Parameters:
+ *   datalen - item size
+ *   name    - used for debugging
+ */
+struct hash * hashinit( int datalen, char const * name );
+
+/*
+ * hash_free() - free a hash table, given its handle
+ */
+void hash_free( struct hash * );
+void hashdone( struct hash * );
+
+/*
+ * hashenumerate() - call f(i, data) on each item, i in the hash table. The
+ * enumeration order is unspecified.
+ */
+void hashenumerate( struct hash *, void (* f)( void *, void * ), void * data );
+
+/*
+ * hash_insert() - insert a new item in a hash table, or return an existing one.
+ *
+ * Preconditions:
+ *   - hp must be a hash table created by hashinit()
+ *   - key must be an object created by object_new()
+ *
+ * Postconditions:
+ *   - if the key does not already exist in the hash table, *found == 0 and the
+ *     result will be a pointer to an uninitialized item. The key of the new
+ *     item must be set to a value equal to key before any further operations on
+ *     the hash table except hashdone().
+ *   - if the key is present then *found == 1 and the result is a pointer to the
+ *     existing record.
+ */
+HASHDATA * hash_insert( struct hash *, OBJECT * key, int * found );
+
+/*
+ * hash_find() - find a record in the table or NULL if none exists
+ */
+HASHDATA * hash_find( struct hash *, OBJECT * key );
+
+struct hashstats {
+    int count;
+    int num_items;
+    int tab_size;
+    int item_size;
+    int sets;
+    int num_hashes;
+};
+
+void hashstats_init( struct hashstats * stats );
+void hashstats_add( struct hashstats * stats, struct hash * );
+void hashstats_print( struct hashstats * stats, char const * name );
+
+#endif