* generic/tclStubInit.c:

* generic/tclObj.c:
* generic/tclInt.h:
* generic/tclHash.c:
* generic/tclDecls.h:
* generic/tcl.h:
* generic/tcl.decls:
* doc/Hash.3: Applied patch from Paul Duffin to extend hash tables
to allow custom key types, such as Tcl_Obj *'s, and others.

7 files changed, 1115 insertions, 653 deletions

diff --git a/generic/tcl.decls b/generic/tcl.decls
index 39a6c21..fd5bb54 100644
--- a/generic/tcl.decls
+++ b/generic/tcl.decls
@@ -10,7 +10,7 @@
 # See the file "license.terms" for information on usage and redistribution
 # of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 # 
-# RCS: @(#) $Id: tcl.decls,v 1.35 2000/05/08 21:59:58 hobbs Exp $
+# RCS: @(#) $Id: tcl.decls,v 1.36 2000/07/19 22:15:29 ericm Exp $
 
 library tcl
 
@@ -1388,6 +1388,25 @@ declare 402 generic {
 	    CONST Tcl_UniChar *pattern, int nocase)
 }
 
+declare 403 generic {
+    Tcl_HashEntry *Tcl_FindHashEntry(Tcl_HashTable *tablePtr, \
+	    CONST char *key)
+}
+
+declare 404 generic {
+    Tcl_HashEntry *Tcl_CreateHashEntry(Tcl_HashTable *tablePtr, \
+	    CONST char *key, int *newPtr)
+}
+
+declare 405 generic {
+    void Tcl_InitHashTableEx(Tcl_HashTable *tablePtr, int keyType, \
+	    Tcl_HashKeyType *typePtr)
+}
+
+declare 406 generic {
+    void Tcl_InitObjHashTable(Tcl_HashTable *tablePtr)
+}
+
 ##############################################################################
 
 # Define the platform specific public Tcl interface.  These functions are
diff --git a/generic/tcl.h b/generic/tcl.h
index ed6c2ac..2add458 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -12,7 +12,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tcl.h,v 1.72 2000/06/24 00:26:08 ericm Exp $
+ * RCS: @(#) $Id: tcl.h,v 1.73 2000/07/19 22:15:29 ericm Exp $
  */
 
 #ifndef _TCL
@@ -337,6 +337,14 @@ typedef long LONG;
 #endif
 
 /*
+ * This flag controls whether binary compatability is maintained with
+ * extensions built against a previous version of Tcl.
+ */
+#ifndef TCL_PRESERVE_BINARY_COMPATABILITY
+#define TCL_PRESERVE_BINARY_COMPATABILITY 1
+#endif
+    
+/*
  * Data structures defined opaquely in this module. The definitions below
  * just provide dummy types. A few fields are made visible in Tcl_Interp
  * structures, namely those used for returning a string result from
@@ -942,13 +950,30 @@ typedef struct Tcl_DString {
 #define TCL_LINK_READ_ONLY	0x80
 
 /*
- * Forward declaration of Tcl_HashTable.  Needed by some C++ compilers
- * to prevent errors when the forward reference to Tcl_HashTable is
- * encountered in the Tcl_HashEntry structure.
+ * Forward declarations of Tcl_HashTable and related types.
  */
 
-#ifdef __cplusplus
-struct Tcl_HashTable;
+typedef struct Tcl_HashKeyType Tcl_HashKeyType;
+typedef struct Tcl_HashTable Tcl_HashTable;
+typedef struct Tcl_HashEntry Tcl_HashEntry;
+    
+typedef unsigned int (Tcl_HashKeyProc) _ANSI_ARGS_((Tcl_HashTable *tablePtr,
+	VOID *keyPtr));
+typedef int (Tcl_CompareHashKeysProc) _ANSI_ARGS_((VOID *keyPtr,
+	Tcl_HashEntry *hPtr));
+typedef Tcl_HashEntry *(Tcl_AllocHashEntryProc) _ANSI_ARGS_((
+	Tcl_HashTable *tablePtr, VOID *keyPtr));
+typedef void (Tcl_FreeHashEntryProc) _ANSI_ARGS_((Tcl_HashEntry *hPtr));
+
+/*
+ * This flag controls whether the hash table stores the hash of a key, or
+ * recalculates it. There should be no reason for turning this flag off
+ * as it is completely binary and source compatible unless you directly
+ * access the bucketPtr member of the Tcl_HashTableEntry structure. This
+ * member has been removed and the space used to store the hash value.
+ */
+#ifndef TCL_HASH_KEY_STORE_HASH
+#define TCL_HASH_KEY_STORE_HASH 1
 #endif
 
 /*
@@ -957,14 +982,25 @@ struct Tcl_HashTable;
  * defined below.
  */
 
-typedef struct Tcl_HashEntry {
-    struct Tcl_HashEntry *nextPtr;	/* Pointer to next entry in this
+struct Tcl_HashEntry {
+    Tcl_HashEntry *nextPtr;		/* Pointer to next entry in this
 					 * hash bucket, or NULL for end of
 					 * chain. */
-    struct Tcl_HashTable *tablePtr;	/* Pointer to table containing entry. */
-    struct Tcl_HashEntry **bucketPtr;	/* Pointer to bucket that points to
+    Tcl_HashTable *tablePtr;		/* Pointer to table containing entry. */
+#if TCL_HASH_KEY_STORE_HASH
+#   if TCL_PRESERVE_BINARY_COMPATABILITY
+    VOID *hash;				/* Hash value, stored as pointer to
+					 * ensure that the offsets of the
+					 * fields in this structure are not
+					 * changed. */
+#   else
+    unsigned int hash;			/* Hash value. */
+#   endif
+#else
+    Tcl_HashEntry **bucketPtr;		/* Pointer to bucket that points to
 					 * first entry in this entry's chain:
 					 * used for deleting the entry. */
+#endif
     ClientData clientData;		/* Application stores something here
 					 * with Tcl_SetHashValue. */
     union {				/* Key has one of these forms: */
@@ -978,16 +1014,72 @@ typedef struct Tcl_HashEntry {
 					 * will be as large as needed to hold
 					 * the key. */
     } key;				/* MUST BE LAST FIELD IN RECORD!! */
-} Tcl_HashEntry;
+};
 
 /*
+ * Flags used in Tcl_HashKeyType.
+ *
+ * TCL_HASH_KEY_RANDOMIZE_HASH:
+ *				There are some things, pointers for example
+ *				which don't hash well because they do not use
+ *				the lower bits. If this flag is set then the
+ *				hash table will attempt to rectify this by
+ *				randomising the bits and then using the upper
+ *				N bits as the index into the table.
+ */
+#define TCL_HASH_KEY_RANDOMIZE_HASH 0x1
+    
+/*
+ * Structure definition for the methods associated with a hash table
+ * key type.
+ */
+#define TCL_HASH_KEY_TYPE_VERSION 1
+struct Tcl_HashKeyType {
+    int version;		/* Version of the table. If this structure is
+				 * extended in future then the version can be
+				 * used to distinguish between different
+				 * structures. 
+				 */
+
+    int flags;			/* Flags, see above for details. */
+    
+    /* Calculates a hash value for the key. If this is NULL then the pointer
+     * itself is used as a hash value.
+     */
+    Tcl_HashKeyProc *hashKeyProc;
+
+    /* Compares two keys and returns zero if they do not match, and non-zero
+     * if they do. If this is NULL then the pointers are compared.
+     */
+    Tcl_CompareHashKeysProc *compareKeysProc;
+
+    /* Called to allocate memory for a new entry, i.e. if the key is a
+     * string then this could allocate a single block which contains enough
+     * space for both the entry and the string. Only the key field of the
+     * allocated Tcl_HashEntry structure needs to be filled in. If something
+     * else needs to be done to the key, i.e. incrementing a reference count
+     * then that should be done by this function. If this is NULL then Tcl_Alloc
+     * is used to allocate enough space for a Tcl_HashEntry and the key pointer
+     * is assigned to key.oneWordValue.
+     */
+    Tcl_AllocHashEntryProc *allocEntryProc;
+
+    /* Called to free memory associated with an entry. If something else needs
+     * to be done to the key, i.e. decrementing a reference count then that
+     * should be done by this function. If this is NULL then Tcl_Free is used
+     * to free the Tcl_HashEntry.
+     */
+    Tcl_FreeHashEntryProc *freeEntryProc;
+};
+    
+/*
  * Structure definition for a hash table.  Must be in tcl.h so clients
  * can allocate space for these structures, but clients should never
  * access any fields in this structure.
  */
 
 #define TCL_SMALL_HASH_TABLE 4
-typedef struct Tcl_HashTable {
+struct Tcl_HashTable {
     Tcl_HashEntry **buckets;		/* Pointer to bucket array.  Each
 					 * element points to first entry in
 					 * bucket's hash chain, or NULL. */
@@ -1006,16 +1098,20 @@ typedef struct Tcl_HashTable {
     int mask;				/* Mask value used in hashing
 					 * function. */
     int keyType;			/* Type of keys used in this table. 
-					 * It's either TCL_OBJ_KEYS,
+					 * It's either TCL_CUSTOM_KEYS,
 					 * TCL_STRING_KEYS, TCL_ONE_WORD_KEYS,
 					 * or an integer giving the number of
 					 * ints that is the size of the key.
 					 */
-    Tcl_HashEntry *(*findProc) _ANSI_ARGS_((struct Tcl_HashTable *tablePtr,
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    Tcl_HashEntry *(*findProc) _ANSI_ARGS_((Tcl_HashTable *tablePtr,
 	    CONST char *key));
-    Tcl_HashEntry *(*createProc) _ANSI_ARGS_((struct Tcl_HashTable *tablePtr,
+    Tcl_HashEntry *(*createProc) _ANSI_ARGS_((Tcl_HashTable *tablePtr,
 	    CONST char *key, int *newPtr));
-} Tcl_HashTable;
+#endif
+    Tcl_HashKeyType *typePtr;		/* Type of the keys used in the
+					 * Tcl_HashTable. */
+};
 
 /*
  * Structure definition for information used to keep track of searches
@@ -1032,35 +1128,75 @@ typedef struct Tcl_HashSearch {
 
 /*
  * Acceptable key types for hash tables:
+ *
+ * TCL_STRING_KEYS:		The keys are strings, they are copied into
+ *				the entry.
+ * TCL_ONE_WORD_KEYS:		The keys are pointers, the pointer is stored
+ *				in the entry.
+ * TCL_CUSTOM_TYPE_KEYS:	The keys are arbitrary types which are copied
+ *				into the entry.
+ * TCL_CUSTOM_PTR_KEYS:		The keys are pointers to arbitrary types, the
+ *				pointer is stored in the entry.
+ *
+ * While maintaining binary compatability the above have to be distinct
+ * values as they are used to differentiate between old versions of the
+ * hash table which don't have a typePtr and new ones which do. Once binary
+ * compatability is discarded in favour of making more wide spread changes
+ * TCL_STRING_KEYS can be the same as TCL_CUSTOM_TYPE_KEYS, and
+ * TCL_ONE_WORD_KEYS can be the same as TCL_CUSTOM_PTR_KEYS because they
+ * simply determine how the key is accessed from the entry and not the
+ * behaviour.
  */
 
-#define TCL_OBJ_KEYS		-1
 #define TCL_STRING_KEYS		0
 #define TCL_ONE_WORD_KEYS	1
 
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+#   define TCL_CUSTOM_TYPE_KEYS		-2
+#   define TCL_CUSTOM_PTR_KEYS		-1
+#else
+#   define TCL_CUSTOM_TYPE_KEYS		TCL_STRING_KEYS
+#   define TCL_CUSTOM_PTR_KEYS		TCL_ONE_WORD_KEYS
+#endif
+
 /*
  * Macros for clients to use to access fields of hash entries:
  */
 
 #define Tcl_GetHashValue(h) ((h)->clientData)
 #define Tcl_SetHashValue(h, value) ((h)->clientData = (ClientData) (value))
-#define Tcl_GetHashKey(tablePtr, h) \
-    ((char *) (((tablePtr)->keyType == TCL_ONE_WORD_KEYS || \
-		(tablePtr)->keyType == TCL_OBJ_KEYS) \
-	       ? (h)->key.oneWordValue \
-	       : (h)->key.string))
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+#   define Tcl_GetHashKey(tablePtr, h) \
+	((char *) (((tablePtr)->keyType == TCL_ONE_WORD_KEYS || \
+		    (tablePtr)->keyType == TCL_CUSTOM_PTR_KEYS) \
+		   ? (h)->key.oneWordValue \
+		   : (h)->key.string))
+#else
+#   define Tcl_GetHashKey(tablePtr, h) \
+	((char *) (((tablePtr)->keyType == TCL_ONE_WORD_KEYS) \
+		   ? (h)->key.oneWordValue \
+		   : (h)->key.string))
+#endif
 
 /*
  * Macros to use for clients to use to invoke find and create procedures
  * for hash tables:
  */
 
-#define Tcl_FindHashEntry(tablePtr, key) \
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+#   define Tcl_FindHashEntry(tablePtr, key) \
 	(*((tablePtr)->findProc))(tablePtr, key)
-#define Tcl_CreateHashEntry(tablePtr, key, newPtr) \
+#   define Tcl_CreateHashEntry(tablePtr, key, newPtr) \
 	(*((tablePtr)->createProc))(tablePtr, key, newPtr)
+#endif
 
 /*
+ * Macro to use new extended version of Tcl_InitHashTable.
+ */
+#define Tcl_InitHashTable(tablePtr, keyType) \
+	Tcl_InitHashTableEx(tablePtr, keyType, NULL)
+    
+/*
  * Flag values to pass to Tcl_DoOneEvent to disable searches
  * for some kinds of events:
  */
diff --git a/generic/tclDecls.h b/generic/tclDecls.h
index 56c1d76..098010b 100644
--- a/generic/tclDecls.h
+++ b/generic/tclDecls.h
@@ -8,7 +8,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclDecls.h,v 1.36 2000/05/08 21:59:59 hobbs Exp $
+ * RCS: @(#) $Id: tclDecls.h,v 1.37 2000/07/19 22:15:29 ericm Exp $
  */
 
 #ifndef _TCLDECLS
@@ -1254,6 +1254,20 @@ EXTERN int		Tcl_UniCharNcasecmp _ANSI_ARGS_((
 EXTERN int		Tcl_UniCharCaseMatch _ANSI_ARGS_((
 				CONST Tcl_UniChar * ustr, 
 				CONST Tcl_UniChar * pattern, int nocase));
+/* 403 */
+EXTERN Tcl_HashEntry *	Tcl_FindHashEntry _ANSI_ARGS_((
+				Tcl_HashTable * tablePtr, CONST char * key));
+/* 404 */
+EXTERN Tcl_HashEntry *	Tcl_CreateHashEntry _ANSI_ARGS_((
+				Tcl_HashTable * tablePtr, CONST char * key, 
+				int * newPtr));
+/* 405 */
+EXTERN void		Tcl_InitHashTableEx _ANSI_ARGS_((
+				Tcl_HashTable * tablePtr, int keyType, 
+				Tcl_HashKeyType * typePtr));
+/* 406 */
+EXTERN void		Tcl_InitObjHashTable _ANSI_ARGS_((
+				Tcl_HashTable * tablePtr));
 
 typedef struct TclStubHooks {
     struct TclPlatStubs *tclPlatStubs;
@@ -1724,6 +1738,10 @@ typedef struct TclStubs {
     int (*tcl_IsChannelExisting) _ANSI_ARGS_((CONST char* channelName)); /* 400 */
     int (*tcl_UniCharNcasecmp) _ANSI_ARGS_((CONST Tcl_UniChar * cs, CONST Tcl_UniChar * ct, unsigned long n)); /* 401 */
     int (*tcl_UniCharCaseMatch) _ANSI_ARGS_((CONST Tcl_UniChar * ustr, CONST Tcl_UniChar * pattern, int nocase)); /* 402 */
+    Tcl_HashEntry * (*tcl_FindHashEntry) _ANSI_ARGS_((Tcl_HashTable * tablePtr, CONST char * key)); /* 403 */
+    Tcl_HashEntry * (*tcl_CreateHashEntry) _ANSI_ARGS_((Tcl_HashTable * tablePtr, CONST char * key, int * newPtr)); /* 404 */
+    void (*tcl_InitHashTableEx) _ANSI_ARGS_((Tcl_HashTable * tablePtr, int keyType, Tcl_HashKeyType * typePtr)); /* 405 */
+    void (*tcl_InitObjHashTable) _ANSI_ARGS_((Tcl_HashTable * tablePtr)); /* 406 */
 } TclStubs;
 
 #ifdef __cplusplus
@@ -3381,6 +3399,22 @@ extern TclStubs *tclStubsPtr;
 #define Tcl_UniCharCaseMatch \
 	(tclStubsPtr->tcl_UniCharCaseMatch) /* 402 */
 #endif
+#ifndef Tcl_FindHashEntry
+#define Tcl_FindHashEntry \
+	(tclStubsPtr->tcl_FindHashEntry) /* 403 */
+#endif
+#ifndef Tcl_CreateHashEntry
+#define Tcl_CreateHashEntry \
+	(tclStubsPtr->tcl_CreateHashEntry) /* 404 */
+#endif
+#ifndef Tcl_InitHashTableEx
+#define Tcl_InitHashTableEx \
+	(tclStubsPtr->tcl_InitHashTableEx) /* 405 */
+#endif
+#ifndef Tcl_InitObjHashTable
+#define Tcl_InitObjHashTable \
+	(tclStubsPtr->tcl_InitObjHashTable) /* 406 */
+#endif
 
 #endif /* defined(USE_TCL_STUBS) && !defined(USE_TCL_STUB_PROCS) */
 
diff --git a/generic/tclHash.c b/generic/tclHash.c
index 374f0e5..026f730 100644
--- a/generic/tclHash.c
+++ b/generic/tclHash.c
@@ -10,19 +10,27 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclHash.c,v 1.4 2000/06/24 00:26:09 ericm Exp $
+ * RCS: @(#) $Id: tclHash.c,v 1.5 2000/07/19 22:15:30 ericm Exp $
  */
 
 #include "tclInt.h"
 
 /*
+ * Prevent macros from clashing with function definitions.
+ */
+
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+#   undef Tcl_FindHashEntry
+#   undef Tcl_CreateHashEntry
+#endif
+
+/*
  * When there are this many entries per bucket, on average, rebuild
  * the hash table to make it larger.
  */
 
 #define REBUILD_MULTIPLIER	3
 
-
 /*
  * The following macro takes a preliminary integer hash value and
  * produces an index into a hash tables bucket list.  The idea is
@@ -35,32 +43,86 @@
     (((((long) (i))*1103515245) >> (tablePtr)->downShift) & (tablePtr)->mask)
 
 /*
+ * Prototypes for the array hash key methods.
+ */
+
+static Tcl_HashEntry *	AllocArrayEntry _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+static int		CompareArrayKeys _ANSI_ARGS_((
+			    VOID *keyPtr, Tcl_HashEntry *hPtr));
+static unsigned int	HashArrayKey _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+
+/*
+ * Prototypes for the one word hash key methods.
+ */
+
+#if 0
+static Tcl_HashEntry *	AllocOneWordEntry _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+static int		CompareOneWordKeys _ANSI_ARGS_((
+			    VOID *keyPtr, Tcl_HashEntry *hPtr));
+static unsigned int	HashOneWordKey _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+#endif			    VOID *keyPtr));
+
+
+/*
+ * Prototypes for the string hash key methods.
+ */
+
+static Tcl_HashEntry *	AllocStringEntry _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+static int		CompareStringKeys _ANSI_ARGS_((
+			    VOID *keyPtr, Tcl_HashEntry *hPtr));
+static unsigned int	HashStringKey _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+
+/*
  * Procedure prototypes for static procedures in this file:
  */
 
-static Tcl_HashEntry *	ArrayFind _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key));
-static Tcl_HashEntry *	ArrayCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key, int *newPtr));
+#if TCL_PRESERVE_BINARY_COMPATABILITY
 static Tcl_HashEntry *	BogusFind _ANSI_ARGS_((Tcl_HashTable *tablePtr,
 			    CONST char *key));
 static Tcl_HashEntry *	BogusCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
 			    CONST char *key, int *newPtr));
-static unsigned int	HashString _ANSI_ARGS_((CONST char *string));
+#endif
+
 static void		RebuildTable _ANSI_ARGS_((Tcl_HashTable *tablePtr));
-static Tcl_HashEntry *	StringFind _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key));
-static Tcl_HashEntry *	StringCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key, int *newPtr));
-static Tcl_HashEntry *	OneWordFind _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key));
-static Tcl_HashEntry *	OneWordCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key, int *newPtr));
-static unsigned int	HashObj _ANSI_ARGS_((Tcl_Obj *objPtr));
-static Tcl_HashEntry *	ObjFind _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key));
-static Tcl_HashEntry *	ObjCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
-			    CONST char *key, int *newPtr));
+
+Tcl_HashKeyType tclArrayHashKeyType = {
+    TCL_HASH_KEY_TYPE_VERSION,		/* version */
+    TCL_HASH_KEY_RANDOMIZE_HASH,	/* flags */
+    HashArrayKey,			/* hashKeyProc */
+    CompareArrayKeys,			/* compareKeysProc */
+    AllocArrayEntry,			/* allocEntryProc */
+    NULL				/* freeEntryProc */
+};
+
+Tcl_HashKeyType tclOneWordHashKeyType = {
+    TCL_HASH_KEY_TYPE_VERSION,		/* version */
+    0,					/* flags */
+    NULL, /* HashOneWordKey, */		/* hashProc */
+    NULL, /* CompareOneWordKey, */	/* compareProc */
+    NULL, /* AllocOneWordKey, */	/* allocEntryProc */
+    NULL  /* FreeOneWordKey, */		/* freeEntryProc */
+};
+
+Tcl_HashKeyType tclStringHashKeyType = {
+    TCL_HASH_KEY_TYPE_VERSION,		/* version */
+    0,					/* flags */
+    HashStringKey,			/* hashKeyProc */
+    CompareStringKeys,			/* compareKeysProc */
+    AllocStringEntry,			/* allocEntryProc */
+    NULL				/* freeEntryProc */
+};
+
 
 /*
  *----------------------------------------------------------------------
@@ -80,6 +142,7 @@ static Tcl_HashEntry *	ObjCreate _ANSI_ARGS_((Tcl_HashTable *tablePtr,
  *----------------------------------------------------------------------
  */
 
+#undef Tcl_InitHashTable
 void
 Tcl_InitHashTable(tablePtr, keyType)
     register Tcl_HashTable *tablePtr;	/* Pointer to table record, which
@@ -88,8 +151,48 @@ Tcl_InitHashTable(tablePtr, keyType)
 					 * TCL_STRING_KEYS, TCL_ONE_WORD_KEYS,
 					 * or an integer >= 2. */
 {
+    /*
+     * Use a special value to inform the extended version that it must
+     * not access any of the new fields in the Tcl_HashTable. If an
+     * extension is rebuilt then any calls to this function will be
+     * redirected to the extended version by a macro.
+     */
+    Tcl_InitHashTableEx(tablePtr, keyType, (Tcl_HashKeyType *) -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_InitHashTableEx --
+ *
+ *	Given storage for a hash table, set up the fields to prepare
+ *	the hash table for use. This is an extended version of
+ *	Tcl_InitHashTableEx which supports user defined keys.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	TablePtr is now ready to be passed to Tcl_FindHashEntry and
+ *	Tcl_CreateHashEntry.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_InitHashTableEx(tablePtr, keyType, typePtr)
+    register Tcl_HashTable *tablePtr;	/* Pointer to table record, which
+					 * is supplied by the caller. */
+    int keyType;			/* Type of keys to use in table:
+					 * TCL_STRING_KEYS, TCL_ONE_WORD_KEYS,
+					 * TCL_CUSTOM_TYPE_KEYS,
+					 * TCL_CUSTOM_PTR_KEYS,  or an
+					 * integer >= 2. */
+    Tcl_HashKeyType *typePtr;		/* Pointer to structure which defines
+					 * the behaviour of this table. */
+{
 #if (TCL_SMALL_HASH_TABLE != 4) 
-    panic("Tcl_InitHashTable: TCL_SMALL_HASH_TABLE is %d, not 4\n",
+    panic("Tcl_InitHashTableEx: TCL_SMALL_HASH_TABLE is %d, not 4\n",
 	    TCL_SMALL_HASH_TABLE);
 #endif
     
@@ -102,19 +205,280 @@ Tcl_InitHashTable(tablePtr, keyType)
     tablePtr->downShift = 28;
     tablePtr->mask = 3;
     tablePtr->keyType = keyType;
-    if (keyType == TCL_OBJ_KEYS) {
-	tablePtr->findProc = ObjFind;
-	tablePtr->createProc = ObjCreate;
-    } else if (keyType == TCL_STRING_KEYS) {
-	tablePtr->findProc = StringFind;
-	tablePtr->createProc = StringCreate;
-    } else if (keyType == TCL_ONE_WORD_KEYS) {
-	tablePtr->findProc = OneWordFind;
-	tablePtr->createProc = OneWordCreate;
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    tablePtr->findProc = Tcl_FindHashEntry;
+    tablePtr->createProc = Tcl_CreateHashEntry;
+
+    if (typePtr == NULL) {
+	/*
+	 * The caller has been rebuilt so the hash table is an extended
+	 * version.
+	 */
+    } else if (typePtr != (Tcl_HashKeyType *) -1) {
+	/*
+	 * The caller is requesting a customized hash table so it must be
+	 * an extended version.
+	 */
+	tablePtr->typePtr = typePtr;
+    } else {
+	/*
+	 * The caller has not been rebuilt so the hash table is not
+	 * extended.
+	 */
+    }
+#else
+    if (typePtr == NULL) {
+	/*
+	 * Use the key type to decide which key type is needed.
+	 */
+	if (keyType == TCL_STRING_KEYS) {
+	    typePtr = &tclStringHashKeyType;
+	} else if (keyType == TCL_ONE_WORD_KEYS) {
+	    typePtr = &tclOneWordHashKeyType;
+	} else if (keyType == TCL_CUSTOM_TYPE_KEYS) {
+	    Tcl_Panic ("No type structure specified for TCL_CUSTOM_TYPE_KEYS");
+	} else if (keyType == TCL_CUSTOM_PTR_KEYS) {
+	    Tcl_Panic ("No type structure specified for TCL_CUSTOM_PTR_KEYS");
+	} else {
+	    typePtr = &tclArrayHashKeyType;
+	}
+    } else if (typePtr == (Tcl_HashKeyType *) -1) {
+	/*
+	 * If the caller has not been rebuilt then we cannot continue as
+	 * the hash table is not an extended version.
+	 */
+	Tcl_Panic ("Hash table is not compatible");
+    }
+    tablePtr->typePtr = typePtr;
+#endif
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_FindHashEntry --
+ *
+ *	Given a hash table find the entry with a matching key.
+ *
+ * Results:
+ *	The return value is a token for the matching entry in the
+ *	hash table, or NULL if there was no matching entry.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_HashEntry *
+Tcl_FindHashEntry(tablePtr, key)
+    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
+    CONST char *key;		/* Key to use to find matching entry. */
+{
+    register Tcl_HashEntry *hPtr;
+    Tcl_HashKeyType *typePtr;
+    unsigned int hash;
+    int index;
+
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    if (tablePtr->keyType == TCL_STRING_KEYS) {
+	typePtr = &tclStringHashKeyType;
+    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
+	typePtr = &tclOneWordHashKeyType;
+    } else if (tablePtr->keyType == TCL_CUSTOM_TYPE_KEYS
+	       || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) {
+	typePtr = tablePtr->typePtr;
     } else {
-	tablePtr->findProc = ArrayFind;
-	tablePtr->createProc = ArrayCreate;
-    };
+	typePtr = &tclArrayHashKeyType;
+    }
+#else
+    typePtr = tablePtr->typePtr;
+    if (typePtr == NULL) {
+	Tcl_Panic("called Tcl_FindHashEntry on deleted table");
+	return NULL;
+    }
+#endif
+
+    if (typePtr->hashKeyProc) {
+	hash = typePtr->hashKeyProc (tablePtr, (VOID *) key);
+	if (typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) {
+	    index = RANDOM_INDEX (tablePtr, hash);
+	} else {
+	    index = hash & tablePtr->mask;
+	}
+    } else {
+	hash = (unsigned int) key;
+	index = RANDOM_INDEX (tablePtr, hash);
+    }
+
+    /*
+     * Search all of the entries in the appropriate bucket.
+     */
+
+    if (typePtr->compareKeysProc) {
+	for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
+	        hPtr = hPtr->nextPtr) {
+#if TCL_HASH_KEY_STORE_HASH
+	    if (hash != (unsigned int) hPtr->hash) {
+		continue;
+	    }
+#endif
+	    if (typePtr->compareKeysProc ((VOID *) key, hPtr)) {
+		return hPtr;
+	    }
+	}
+    } else {
+	for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
+	        hPtr = hPtr->nextPtr) {
+#if TCL_HASH_KEY_STORE_HASH
+	    if (hash != (unsigned int) hPtr->hash) {
+		continue;
+	    }
+#endif
+	    if (key == hPtr->key.oneWordValue) {
+		return hPtr;
+	    }
+	}
+    }
+    
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_CreateHashEntry --
+ *
+ *	Given a hash table with string keys, and a string key, find
+ *	the entry with a matching key.  If there is no matching entry,
+ *	then create a new entry that does match.
+ *
+ * Results:
+ *	The return value is a pointer to the matching entry.  If this
+ *	is a newly-created entry, then *newPtr will be set to a non-zero
+ *	value;  otherwise *newPtr will be set to 0.  If this is a new
+ *	entry the value stored in the entry will initially be 0.
+ *
+ * Side effects:
+ *	A new entry may be added to the hash table.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_HashEntry *
+Tcl_CreateHashEntry(tablePtr, key, newPtr)
+    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
+    CONST char *key;		/* Key to use to find or create matching
+				 * entry. */
+    int *newPtr;		/* Store info here telling whether a new
+				 * entry was created. */
+{
+    register Tcl_HashEntry *hPtr;
+    Tcl_HashKeyType *typePtr;
+    unsigned int hash;
+    int index;
+
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    if (tablePtr->keyType == TCL_STRING_KEYS) {
+	typePtr = &tclStringHashKeyType;
+    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
+	typePtr = &tclOneWordHashKeyType;
+    } else if (tablePtr->keyType == TCL_CUSTOM_TYPE_KEYS
+	       || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) {
+	typePtr = tablePtr->typePtr;
+    } else {
+	typePtr = &tclArrayHashKeyType;
+    }
+#else
+    typePtr = tablePtr->typePtr;
+    if (typePtr == NULL) {
+	Tcl_Panic("called Tcl_CreateHashEntry on deleted table");
+	return NULL;
+    }
+#endif
+
+    if (typePtr->hashKeyProc) {
+	hash = typePtr->hashKeyProc (tablePtr, (VOID *) key);
+	if (typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) {
+	    index = RANDOM_INDEX (tablePtr, hash);
+	} else {
+	    index = hash & tablePtr->mask;
+	}
+    } else {
+	hash = (unsigned int) key;
+	index = RANDOM_INDEX (tablePtr, hash);
+    }
+
+    /*
+     * Search all of the entries in the appropriate bucket.
+     */
+
+    if (typePtr->compareKeysProc) {
+	for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
+	        hPtr = hPtr->nextPtr) {
+#if TCL_HASH_KEY_STORE_HASH
+	    if (hash != (unsigned int) hPtr->hash) {
+		continue;
+	    }
+#endif
+	    if (typePtr->compareKeysProc ((VOID *) key, hPtr)) {
+		*newPtr = 0;
+		return hPtr;
+	    }
+	}
+    } else {
+	for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
+	        hPtr = hPtr->nextPtr) {
+#if TCL_HASH_KEY_STORE_HASH
+	    if (hash != (unsigned int) hPtr->hash) {
+		continue;
+	    }
+#endif
+	    if (key == hPtr->key.oneWordValue) {
+		*newPtr = 0;
+		return hPtr;
+	    }
+	}
+    }
+
+    /*
+     * Entry not found.  Add a new one to the bucket.
+     */
+
+    *newPtr = 1;
+    if (typePtr->allocEntryProc) {
+	hPtr = typePtr->allocEntryProc (tablePtr, (VOID *) key);
+    } else {
+	hPtr = (Tcl_HashEntry *) ckalloc((unsigned) sizeof(Tcl_HashEntry));
+	hPtr->key.oneWordValue = (char *) key;
+    }
+					 
+    hPtr->tablePtr = tablePtr;
+#if TCL_HASH_KEY_STORE_HASH
+#   if TCL_PRESERVE_BINARY_COMPATABILITY
+    hPtr->hash = (VOID *) hash;
+#   else
+    hPtr->hash = hash;
+#   endif
+    hPtr->nextPtr = tablePtr->buckets[index];
+    tablePtr->buckets[index] = hPtr;
+#else
+    hPtr->bucketPtr = &(tablePtr->buckets[index]);
+    hPtr->nextPtr = *hPtr->bucketPtr;
+    *hPtr->bucketPtr = hPtr;
+#endif
+    hPtr->clientData = 0;
+    tablePtr->numEntries++;
+
+    /*
+     * If the table has exceeded a decent size, rebuild it with many
+     * more buckets.
+     */
+
+    if (tablePtr->numEntries >= tablePtr->rebuildSize) {
+	RebuildTable(tablePtr);
+    }
+    return hPtr;
 }
 
 /*
@@ -141,11 +505,47 @@ Tcl_DeleteHashEntry(entryPtr)
     Tcl_HashEntry *entryPtr;
 {
     register Tcl_HashEntry *prevPtr;
+    Tcl_HashKeyType *typePtr;
+    Tcl_HashTable *tablePtr;
+    Tcl_HashEntry **bucketPtr;
+#if TCL_HASH_KEY_STORE_HASH
+    int index;
+#endif
+
+    tablePtr = entryPtr->tablePtr;
 
-    if (*entryPtr->bucketPtr == entryPtr) {
-	*entryPtr->bucketPtr = entryPtr->nextPtr;
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    if (tablePtr->keyType == TCL_STRING_KEYS) {
+	typePtr = &tclStringHashKeyType;
+    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
+	typePtr = &tclOneWordHashKeyType;
+    } else if (tablePtr->keyType == TCL_CUSTOM_TYPE_KEYS
+	       || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) {
+	typePtr = tablePtr->typePtr;
     } else {
-	for (prevPtr = *entryPtr->bucketPtr; ; prevPtr = prevPtr->nextPtr) {
+	typePtr = &tclArrayHashKeyType;
+    }
+#else
+    typePtr = tablePtr->typePtr;
+#endif
+    
+#if TCL_HASH_KEY_STORE_HASH
+    if (typePtr->hashKeyProc == NULL
+	|| typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) {
+	index = RANDOM_INDEX (tablePtr, entryPtr->hash);
+    } else {
+	index = ((unsigned int) entryPtr->hash) & tablePtr->mask;
+    }
+
+    bucketPtr = &(tablePtr->buckets[index]);
+#else
+    bucketPtr = entryPtr->bucketPtr;
+#endif
+    
+    if (*bucketPtr == entryPtr) {
+	*bucketPtr = entryPtr->nextPtr;
+    } else {
+	for (prevPtr = *bucketPtr; ; prevPtr = prevPtr->nextPtr) {
 	    if (prevPtr == NULL) {
 		panic("malformed bucket chain in Tcl_DeleteHashEntry");
 	    }
@@ -155,12 +555,13 @@ Tcl_DeleteHashEntry(entryPtr)
 	    }
 	}
     }
-    
-    if (entryPtr->tablePtr->keyType == TCL_OBJ_KEYS) {
-	Tcl_DecrRefCount (entryPtr->key.objPtr);
+
+    tablePtr->numEntries--;
+    if (typePtr->freeEntryProc) {
+	typePtr->freeEntryProc (entryPtr);
+    } else {
+	ckfree((char *) entryPtr);
     }
-    entryPtr->tablePtr->numEntries--;
-    ckfree((char *) entryPtr);
 }
 
 /*
@@ -185,8 +586,24 @@ Tcl_DeleteHashTable(tablePtr)
     register Tcl_HashTable *tablePtr;		/* Table to delete. */
 {
     register Tcl_HashEntry *hPtr, *nextPtr;
+    Tcl_HashKeyType *typePtr;
     int i;
 
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    if (tablePtr->keyType == TCL_STRING_KEYS) {
+	typePtr = &tclStringHashKeyType;
+    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
+	typePtr = &tclOneWordHashKeyType;
+    } else if (tablePtr->keyType == TCL_CUSTOM_TYPE_KEYS
+	       || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) {
+	typePtr = tablePtr->typePtr;
+    } else {
+	typePtr = &tclArrayHashKeyType;
+    }
+#else
+    typePtr = tablePtr->typePtr;
+#endif
+
     /*
      * Free up all the entries in the table.
      */
@@ -195,10 +612,11 @@ Tcl_DeleteHashTable(tablePtr)
 	hPtr = tablePtr->buckets[i];
 	while (hPtr != NULL) {
 	    nextPtr = hPtr->nextPtr;
-	    if (tablePtr->keyType == TCL_OBJ_KEYS) {
-		Tcl_DecrRefCount (hPtr->key.objPtr);
+	    if (typePtr->freeEntryProc) {
+		typePtr->freeEntryProc (hPtr);
+	    } else {
+		ckfree((char *) hPtr);
 	    }
-	    ckfree((char *) hPtr);
 	    hPtr = nextPtr;
 	}
     }
@@ -216,8 +634,12 @@ Tcl_DeleteHashTable(tablePtr)
      * re-initialization.
      */
 
+#if TCL_PRESERVE_BINARY_COMPATABILITY
     tablePtr->findProc = BogusFind;
     tablePtr->createProc = BogusCreate;
+#else
+    tablePtr->typePtr = NULL;
+#endif
 }
 
 /*
@@ -370,14 +792,12 @@ Tcl_HashStats(tablePtr)
 /*
  *----------------------------------------------------------------------
  *
- * HashString --
+ * AllocArrayEntry --
  *
- *	Compute a one-word summary of a text string, which can be
- *	used to generate a hash index.
+ *	Allocate space for a Tcl_HashEntry containing the array key.
  *
  * Results:
- *	The return value is a one-word summary of the information in
- *	string.
+ *	The return value is a pointer to the created entry.
  *
  * Side effects:
  *	None.
@@ -385,52 +805,39 @@ Tcl_HashStats(tablePtr)
  *----------------------------------------------------------------------
  */
 
-static unsigned int
-HashString(string)
-    register CONST char *string;/* String from which to compute hash value. */
+static Tcl_HashEntry *
+AllocArrayEntry(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key to store in the hash table entry. */
 {
-    register unsigned int result;
-    register int c;
-
-    /*
-     * I tried a zillion different hash functions and asked many other
-     * people for advice.  Many people had their own favorite functions,
-     * all different, but no-one had much idea why they were good ones.
-     * I chose the one below (multiply by 9 and add new character)
-     * because of the following reasons:
-     *
-     * 1. Multiplying by 10 is perfect for keys that are decimal strings,
-     *    and multiplying by 9 is just about as good.
-     * 2. Times-9 is (shift-left-3) plus (old).  This means that each
-     *    character's bits hang around in the low-order bits of the
-     *    hash value for ever, plus they spread fairly rapidly up to
-     *    the high-order bits to fill out the hash value.  This seems
-     *    works well both for decimal and non-decimal strings.
-     */
+    int *array = (int *) keyPtr;
+    register int *iPtr1, *iPtr2;
+    Tcl_HashEntry *hPtr;
+    int count;
 
-    result = 0;
-    while (1) {
-	c = *string;
-	string++;
-	if (c == 0) {
-	    break;
-	}
-	result += (result<<3) + c;
+    count = tablePtr->keyType;
+    
+    hPtr = (Tcl_HashEntry *) ckalloc((unsigned) (sizeof(Tcl_HashEntry)
+	    + (count*sizeof(int)) - sizeof(hPtr->key)));
+    
+    for (iPtr1 = array, iPtr2 = hPtr->key.words;
+	    count > 0; count--, iPtr1++, iPtr2++) {
+	*iPtr2 = *iPtr1;
     }
-    return result;
+
+    return hPtr;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * StringFind --
+ * CompareArrayKeys --
  *
- *	Given a hash table with string keys, and a string key, find
- *	the entry with a matching key.
+ *	Compares two array keys.
  *
  * Results:
- *	The return value is a token for the matching entry in the
- *	hash table, or NULL if there was no matching entry.
+ *	The return value is 0 if they are different and 1 if they are
+ *	the same.
  *
  * Side effects:
  *	None.
@@ -438,124 +845,38 @@ HashString(string)
  *----------------------------------------------------------------------
  */
 
-static Tcl_HashEntry *
-StringFind(tablePtr, key)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    CONST char *key;		/* Key to use to find matching entry. */
+static int
+CompareArrayKeys(keyPtr, hPtr)
+    VOID *keyPtr;		/* New key to compare. */
+    Tcl_HashEntry *hPtr;	/* Existing key to compare. */
 {
-    register Tcl_HashEntry *hPtr;
-    register CONST char *p1, *p2;
-    int index;
-
-    index = HashString(key) & tablePtr->mask;
-
-    /*
-     * Search all of the entries in the appropriate bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	for (p1 = key, p2 = hPtr->key.string; ; p1++, p2++) {
-	    if (*p1 != *p2) {
-		break;
-	    }
-	    if (*p1 == '\0') {
-		return hPtr;
-	    }
+    register CONST char *iPtr1 = (CONST char *) keyPtr;
+    register CONST char *iPtr2 = (CONST char *) hPtr->key.words;
+    Tcl_HashTable *tablePtr = hPtr->tablePtr;
+    int count;
+
+    for (count = tablePtr->keyType; ; count--, iPtr1++, iPtr2++) {
+	if (count == 0) {
+	    return 1;
 	}
-    }
-    return NULL;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * StringCreate --
- *
- *	Given a hash table with string keys, and a string key, find
- *	the entry with a matching key.  If there is no matching entry,
- *	then create a new entry that does match.
- *
- * Results:
- *	The return value is a pointer to the matching entry.  If this
- *	is a newly-created entry, then *newPtr will be set to a non-zero
- *	value;  otherwise *newPtr will be set to 0.  If this is a new
- *	entry the value stored in the entry will initially be 0.
- *
- * Side effects:
- *	A new entry may be added to the hash table.
- *
- *----------------------------------------------------------------------
- */
-
-static Tcl_HashEntry *
-StringCreate(tablePtr, key, newPtr)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    CONST char *key;		/* Key to use to find or create matching
-				 * entry. */
-    int *newPtr;		/* Store info here telling whether a new
-				 * entry was created. */
-{
-    register Tcl_HashEntry *hPtr;
-    register CONST char *p1, *p2;
-    int index;
-
-    index = HashString(key) & tablePtr->mask;
-
-    /*
-     * Search all of the entries in this bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	for (p1 = key, p2 = hPtr->key.string; ; p1++, p2++) {
-	    if (*p1 != *p2) {
-		break;
-	    }
-	    if (*p1 == '\0') {
-		*newPtr = 0;
-		return hPtr;
-	    }
+	if (*iPtr1 != *iPtr2) {
+	    break;
 	}
     }
-
-    /*
-     * Entry not found.  Add a new one to the bucket.
-     */
-
-    *newPtr = 1;
-    hPtr = (Tcl_HashEntry *) ckalloc((unsigned)
-	    (sizeof(Tcl_HashEntry) + strlen(key) - (sizeof(hPtr->key) -1)));
-    hPtr->tablePtr = tablePtr;
-    hPtr->bucketPtr = &(tablePtr->buckets[index]);
-    hPtr->nextPtr = *hPtr->bucketPtr;
-    hPtr->clientData = 0;
-    strcpy(hPtr->key.string, key);
-    *hPtr->bucketPtr = hPtr;
-    tablePtr->numEntries++;
-
-    /*
-     * If the table has exceeded a decent size, rebuild it with many
-     * more buckets.
-     */
-
-    if (tablePtr->numEntries >= tablePtr->rebuildSize) {
-	RebuildTable(tablePtr);
-    }
-    return hPtr;
+    return 0;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * OneWordFind --
+ * HashArrayKey --
  *
- *	Given a hash table with one-word keys, and a one-word key, find
- *	the entry with a matching key.
+ *	Compute a one-word summary of an array, which can be
+ *	used to generate a hash index.
  *
  * Results:
- *	The return value is a token for the matching entry in the
- *	hash table, or NULL if there was no matching entry.
+ *	The return value is a one-word summary of the information in
+ *	string.
  *
  * Side effects:
  *	None.
@@ -563,111 +884,63 @@ StringCreate(tablePtr, key, newPtr)
  *----------------------------------------------------------------------
  */
 
-static Tcl_HashEntry *
-OneWordFind(tablePtr, key)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    register CONST char *key;	/* Key to use to find matching entry. */
+static unsigned int
+HashArrayKey(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key from which to compute hash value. */
 {
-    register Tcl_HashEntry *hPtr;
-    int index;
-
-    index = RANDOM_INDEX(tablePtr, key);
-
-    /*
-     * Search all of the entries in the appropriate bucket.
-     */
+    register CONST char *array = (CONST char *) keyPtr;
+    register unsigned int result;
+    int count;
 
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	if (hPtr->key.oneWordValue == key) {
-	    return hPtr;
-	}
+    for (result = 0, count = tablePtr->keyType; count > 0;
+	    count--, array++) {
+	result += *array;
     }
-    return NULL;
+    return result;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * OneWordCreate --
+ * AllocStringEntry --
  *
- *	Given a hash table with one-word keys, and a one-word key, find
- *	the entry with a matching key.  If there is no matching entry,
- *	then create a new entry that does match.
+ *	Allocate space for a Tcl_HashEntry containing the string key.
  *
  * Results:
- *	The return value is a pointer to the matching entry.  If this
- *	is a newly-created entry, then *newPtr will be set to a non-zero
- *	value;  otherwise *newPtr will be set to 0.  If this is a new
- *	entry the value stored in the entry will initially be 0.
+ *	The return value is a pointer to the created entry.
  *
  * Side effects:
- *	A new entry may be added to the hash table.
+ *	None.
  *
  *----------------------------------------------------------------------
  */
 
 static Tcl_HashEntry *
-OneWordCreate(tablePtr, key, newPtr)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    register CONST char *key;	/* Key to use to find or create matching
-				 * entry. */
-    int *newPtr;		/* Store info here telling whether a new
-				 * entry was created. */
+AllocStringEntry(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key to store in the hash table entry. */
 {
-    register Tcl_HashEntry *hPtr;
-    int index;
-
-    index = RANDOM_INDEX(tablePtr, key);
-
-    /*
-     * Search all of the entries in this bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	if (hPtr->key.oneWordValue == key) {
-	    *newPtr = 0;
-	    return hPtr;
-	}
-    }
-
-    /*
-     * Entry not found.  Add a new one to the bucket.
-     */
-
-    *newPtr = 1;
-    hPtr = (Tcl_HashEntry *) ckalloc(sizeof(Tcl_HashEntry));
-    hPtr->tablePtr = tablePtr;
-    hPtr->bucketPtr = &(tablePtr->buckets[index]);
-    hPtr->nextPtr = *hPtr->bucketPtr;
-    hPtr->clientData = 0;
-    hPtr->key.oneWordValue = (char *) key;	/* CONST XXXX */
-    *hPtr->bucketPtr = hPtr;
-    tablePtr->numEntries++;
+    CONST char *string = (CONST char *) keyPtr;
+    Tcl_HashEntry *hPtr;
 
-    /*
-     * If the table has exceeded a decent size, rebuild it with many
-     * more buckets.
-     */
+    hPtr = (Tcl_HashEntry *) ckalloc((unsigned)
+	    (sizeof(Tcl_HashEntry) + strlen(string) + 1 - sizeof(hPtr->key)));
+    strcpy(hPtr->key.string, string);
 
-    if (tablePtr->numEntries >= tablePtr->rebuildSize) {
-	RebuildTable(tablePtr);
-    }
     return hPtr;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * ArrayFind --
+ * CompareStringKeys --
  *
- *	Given a hash table with array-of-int keys, and a key, find
- *	the entry with a matching key.
+ *	Compares two string keys.
  *
  * Results:
- *	The return value is a token for the matching entry in the
- *	hash table, or NULL if there was no matching entry.
+ *	The return value is 0 if they are different and 1 if they are
+ *	the same.
  *
  * Side effects:
  *	None.
@@ -675,198 +948,36 @@ OneWordCreate(tablePtr, key, newPtr)
  *----------------------------------------------------------------------
  */
 
-static Tcl_HashEntry *
-ArrayFind(tablePtr, key)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    CONST char *key;		/* Key to use to find matching entry. */
+static int
+CompareStringKeys(keyPtr, hPtr)
+    VOID *keyPtr;		/* New key to compare. */
+    Tcl_HashEntry *hPtr;		/* Existing key to compare. */
 {
-    register Tcl_HashEntry *hPtr;
-    int *arrayPtr = (int *) key;
-    register int *iPtr1, *iPtr2;
-    int index, count;
-
-    for (index = 0, count = tablePtr->keyType, iPtr1 = arrayPtr;
-	    count > 0; count--, iPtr1++) {
-	index += *iPtr1;
-    }
-    index = RANDOM_INDEX(tablePtr, index);
+    register CONST char *p1 = (CONST char *) keyPtr;
+    register CONST char *p2 = (CONST char *) hPtr->key.string;
 
-    /*
-     * Search all of the entries in the appropriate bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	for (iPtr1 = arrayPtr, iPtr2 = hPtr->key.words,
-		count = tablePtr->keyType; ; count--, iPtr1++, iPtr2++) {
-	    if (count == 0) {
-		return hPtr;
-	    }
-	    if (*iPtr1 != *iPtr2) {
-		break;
-	    }
+    for (;; p1++, p2++) {
+	if (*p1 != *p2) {
+	    break;
 	}
-    }
-    return NULL;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * ArrayCreate --
- *
- *	Given a hash table with one-word keys, and a one-word key, find
- *	the entry with a matching key.  If there is no matching entry,
- *	then create a new entry that does match.
- *
- * Results:
- *	The return value is a pointer to the matching entry.  If this
- *	is a newly-created entry, then *newPtr will be set to a non-zero
- *	value;  otherwise *newPtr will be set to 0.  If this is a new
- *	entry the value stored in the entry will initially be 0.
- *
- * Side effects:
- *	A new entry may be added to the hash table.
- *
- *----------------------------------------------------------------------
- */
-
-static Tcl_HashEntry *
-ArrayCreate(tablePtr, key, newPtr)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    register CONST char *key;	/* Key to use to find or create matching
-				 * entry. */
-    int *newPtr;		/* Store info here telling whether a new
-				 * entry was created. */
-{
-    register Tcl_HashEntry *hPtr;
-    int *arrayPtr = (int *) key;
-    register int *iPtr1, *iPtr2;
-    int index, count;
-
-    for (index = 0, count = tablePtr->keyType, iPtr1 = arrayPtr;
-	    count > 0; count--, iPtr1++) {
-	index += *iPtr1;
-    }
-    index = RANDOM_INDEX(tablePtr, index);
-
-    /*
-     * Search all of the entries in the appropriate bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	for (iPtr1 = arrayPtr, iPtr2 = hPtr->key.words,
-		count = tablePtr->keyType; ; count--, iPtr1++, iPtr2++) {
-	    if (count == 0) {
-		*newPtr = 0;
-		return hPtr;
-	    }
-	    if (*iPtr1 != *iPtr2) {
-		break;
-	    }
+	if (*p1 == '\0') {
+	    return 1;
 	}
     }
-
-    /*
-     * Entry not found.  Add a new one to the bucket.
-     */
-
-    *newPtr = 1;
-    hPtr = (Tcl_HashEntry *) ckalloc((unsigned) (sizeof(Tcl_HashEntry)
-	    + (tablePtr->keyType*sizeof(int)) - 4));
-    hPtr->tablePtr = tablePtr;
-    hPtr->bucketPtr = &(tablePtr->buckets[index]);
-    hPtr->nextPtr = *hPtr->bucketPtr;
-    hPtr->clientData = 0;
-    for (iPtr1 = arrayPtr, iPtr2 = hPtr->key.words, count = tablePtr->keyType;
-	    count > 0; count--, iPtr1++, iPtr2++) {
-	*iPtr2 = *iPtr1;
-    }
-    *hPtr->bucketPtr = hPtr;
-    tablePtr->numEntries++;
-
-    /*
-     * If the table has exceeded a decent size, rebuild it with many
-     * more buckets.
-     */
-
-    if (tablePtr->numEntries >= tablePtr->rebuildSize) {
-	RebuildTable(tablePtr);
-    }
-    return hPtr;
+    return 0;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * BogusFind --
+ * HashStringKey --
  *
- *	This procedure is invoked when an Tcl_FindHashEntry is called
- *	on a table that has been deleted.
- *
- * Results:
- *	If panic returns (which it shouldn't) this procedure returns
- *	NULL.
- *
- * Side effects:
- *	Generates a panic.
- *
- *----------------------------------------------------------------------
- */
-
-	/* ARGSUSED */
-static Tcl_HashEntry *
-BogusFind(tablePtr, key)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    CONST char *key;		/* Key to use to find matching entry. */
-{
-    panic("called Tcl_FindHashEntry on deleted table");
-    return NULL;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * BogusCreate --
- *
- *	This procedure is invoked when an Tcl_CreateHashEntry is called
- *	on a table that has been deleted.
- *
- * Results:
- *	If panic returns (which it shouldn't) this procedure returns
- *	NULL.
- *
- * Side effects:
- *	Generates a panic.
- *
- *----------------------------------------------------------------------
- */
-
-	/* ARGSUSED */
-static Tcl_HashEntry *
-BogusCreate(tablePtr, key, newPtr)
-    Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
-    CONST char *key;		/* Key to use to find or create matching
-				 * entry. */
-    int *newPtr;		/* Store info here telling whether a new
-				 * entry was created. */
-{
-    panic("called Tcl_CreateHashEntry on deleted table");
-    return NULL;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * HashObj --
- *
- *	Compute a one-word summary of the string representation of the
- *	Tcl_Obj, which can be used to generate a hash index.
+ *	Compute a one-word summary of a text string, which can be
+ *	used to generate a hash index.
  *
  * Results:
  *	The return value is a one-word summary of the information in
- *	the string representation of the Tcl_Obj.
+ *	string.
  *
  * Side effects:
  *	None.
@@ -875,17 +986,14 @@ BogusCreate(tablePtr, key, newPtr)
  */
 
 static unsigned int
-HashObj(objPtr)
-    Tcl_Obj *objPtr;
+HashStringKey(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key from which to compute hash value. */
 {
-    register CONST char *string;
-    register int length;
+    register CONST char *string = (CONST char *) keyPtr;
     register unsigned int result;
     register int c;
 
-    string = Tcl_GetStringFromObj (objPtr, NULL);
-    length = objPtr->length;
-    
     /*
      * I tried a zillion different hash functions and asked many other
      * people for advice.  Many people had their own favorite functions,
@@ -903,11 +1011,10 @@ HashObj(objPtr)
      */
 
     result = 0;
-    while (length) {
+    while (1) {
 	c = *string;
 	string++;
-	length--;
-	if (length == 0) {
+	if (c == 0) {
 	    break;
 	}
 	result += (result<<3) + c;
@@ -915,174 +1022,66 @@ HashObj(objPtr)
     return result;
 }
 
+#if TCL_PRESERVE_BINARY_COMPATABILITY
 /*
  *----------------------------------------------------------------------
  *
- * ObjFind --
+ * BogusFind --
  *
- *	Given a hash table with string keys, and a string key, find
- *	the entry with a matching key.
+ *	This procedure is invoked when an Tcl_FindHashEntry is called
+ *	on a table that has been deleted.
  *
  * Results:
- *	The return value is a token for the matching entry in the
- *	hash table, or NULL if there was no matching entry.
+ *	If panic returns (which it shouldn't) this procedure returns
+ *	NULL.
  *
  * Side effects:
- *	None.
+ *	Generates a panic.
  *
  *----------------------------------------------------------------------
  */
 
+	/* ARGSUSED */
 static Tcl_HashEntry *
-ObjFind(tablePtr, key)
+BogusFind(tablePtr, key)
     Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
     CONST char *key;		/* Key to use to find matching entry. */
 {
-    Tcl_Obj *objPtr = (Tcl_Obj *) key;
-    register Tcl_HashEntry *hPtr;
-    register CONST char *p1, *p2;
-    register int l1, l2;
-    int index;
-
-    index = HashObj(objPtr) & tablePtr->mask;
-
-    /*
-     * Search all of the entries in the appropriate bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	/*
-	 * If the object pointers are the same then they match.
-	 */
-	if (objPtr == hPtr->key.objPtr) {
-	    return hPtr;
-	}
-
-	p1 = Tcl_GetStringFromObj (objPtr, (int *) 0);
-	l1 = objPtr->length;
-	p2 = Tcl_GetStringFromObj (hPtr->key.objPtr, (int *) 0);
-	l2 = hPtr->key.objPtr->length;
-	
-	/*
-	 * If the lengths are different then they do not match.
-	 */
-	if (l1 != l2) {
-	    continue;
-	}
-	
-	for (;; p1++, p2++, l1--) {
-	    if (*p1 != *p2) {
-		break;
-	    }
-	    if (l1 == 0) {
-		return hPtr;
-	    }
-	}
-    }
+    panic("called Tcl_FindHashEntry on deleted table");
     return NULL;
 }
 
 /*
  *----------------------------------------------------------------------
  *
- * ObjCreate --
+ * BogusCreate --
  *
- *	Given a hash table with string keys, and a string key, find
- *	the entry with a matching key.  If there is no matching entry,
- *	then create a new entry that does match.
+ *	This procedure is invoked when an Tcl_CreateHashEntry is called
+ *	on a table that has been deleted.
  *
  * Results:
- *	The return value is a pointer to the matching entry.  If this
- *	is a newly-created entry, then *newPtr will be set to a non-zero
- *	value;  otherwise *newPtr will be set to 0.  If this is a new
- *	entry the value stored in the entry will initially be 0.
+ *	If panic returns (which it shouldn't) this procedure returns
+ *	NULL.
  *
  * Side effects:
- *	A new entry may be added to the hash table.
+ *	Generates a panic.
  *
  *----------------------------------------------------------------------
  */
 
+	/* ARGSUSED */
 static Tcl_HashEntry *
-ObjCreate(tablePtr, key, newPtr)
+BogusCreate(tablePtr, key, newPtr)
     Tcl_HashTable *tablePtr;	/* Table in which to lookup entry. */
     CONST char *key;		/* Key to use to find or create matching
 				 * entry. */
     int *newPtr;		/* Store info here telling whether a new
 				 * entry was created. */
 {
-    Tcl_Obj *objPtr = (Tcl_Obj *) key;
-    register Tcl_HashEntry *hPtr;
-    register CONST char *p1, *p2;
-    register int l1, l2;
-    int index;
-
-    index = HashObj(objPtr) & tablePtr->mask;
-
-    /*
-     * Search all of the entries in this bucket.
-     */
-
-    for (hPtr = tablePtr->buckets[index]; hPtr != NULL;
-	    hPtr = hPtr->nextPtr) {
-	/*
-	 * If the object pointers are the same then they match.
-	 */
-	if (objPtr == hPtr->key.objPtr) {
-	    *newPtr = 0;
-	    return hPtr;
-	}
-
-	p1 = Tcl_GetStringFromObj (objPtr, (int *) 0);
-	l1 = objPtr->length;
-	p2 = Tcl_GetStringFromObj (hPtr->key.objPtr, (int *) 0);
-	l2 = hPtr->key.objPtr->length;
-	
-	/*
-	 * If the lengths are different then they do not match.
-	 */
-	if (l1 != l2) {
-	    continue;
-	}
-	
-	for (;; p1++, p2++, l1--) {
-	    if (*p1 != *p2) {
-		break;
-	    }
-	    if (l1 == 0) {
-		*newPtr = 0;
-		return hPtr;
-	    }
-	}
-    }
-
-    /*
-     * Entry not found.  Add a new one to the bucket.
-     */
-
-    *newPtr = 1;
-    hPtr = (Tcl_HashEntry *)
-	Tcl_Alloc((unsigned) sizeof(Tcl_HashEntry));
-    hPtr->tablePtr = tablePtr;
-    hPtr->bucketPtr = &(tablePtr->buckets[index]);
-    hPtr->nextPtr = *hPtr->bucketPtr;
-    hPtr->clientData = 0;
-    hPtr->key.objPtr = objPtr;
-    Tcl_IncrRefCount (objPtr);
-    *hPtr->bucketPtr = hPtr;
-    tablePtr->numEntries++;
-
-    /*
-     * If the table has exceeded a decent size, rebuild it with many
-     * more buckets.
-     */
-
-    if (tablePtr->numEntries >= tablePtr->rebuildSize) {
-	RebuildTable(tablePtr);
-    }
-    return hPtr;
+    panic("called Tcl_CreateHashEntry on deleted table");
+    return NULL;
 }
+#endif
 
 /*
  *----------------------------------------------------------------------
@@ -1112,6 +1111,8 @@ RebuildTable(tablePtr)
     Tcl_HashEntry **oldBuckets;
     register Tcl_HashEntry **oldChainPtr, **newChainPtr;
     register Tcl_HashEntry *hPtr;
+    Tcl_HashKeyType *typePtr;
+    VOID *key;
 
     oldSize = tablePtr->numBuckets;
     oldBuckets = tablePtr->buckets;
@@ -1132,6 +1133,21 @@ RebuildTable(tablePtr)
     tablePtr->downShift -= 2;
     tablePtr->mask = (tablePtr->mask << 2) + 3;
 
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+    if (tablePtr->keyType == TCL_STRING_KEYS) {
+	typePtr = &tclStringHashKeyType;
+    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
+	typePtr = &tclOneWordHashKeyType;
+    } else if (tablePtr->keyType == TCL_CUSTOM_TYPE_KEYS
+	       || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) {
+	typePtr = tablePtr->typePtr;
+    } else {
+	typePtr = &tclArrayHashKeyType;
+    }
+#else
+    typePtr = tablePtr->typePtr;
+#endif
+
     /*
      * Rehash all of the existing entries into the new bucket array.
      */
@@ -1139,25 +1155,35 @@ RebuildTable(tablePtr)
     for (oldChainPtr = oldBuckets; oldSize > 0; oldSize--, oldChainPtr++) {
 	for (hPtr = *oldChainPtr; hPtr != NULL; hPtr = *oldChainPtr) {
 	    *oldChainPtr = hPtr->nextPtr;
-	    if (tablePtr->keyType == TCL_OBJ_KEYS) {
-		index = HashObj(hPtr->key.objPtr) & tablePtr->mask;
-	    } else if (tablePtr->keyType == TCL_STRING_KEYS) {
-		index = HashString(hPtr->key.string) & tablePtr->mask;
-	    } else if (tablePtr->keyType == TCL_ONE_WORD_KEYS) {
-		index = RANDOM_INDEX(tablePtr, hPtr->key.oneWordValue);
-	    } else {
-		register int *iPtr;
-		int count;
 
-		for (index = 0, count = tablePtr->keyType,
-			iPtr = hPtr->key.words; count > 0; count--, iPtr++) {
-		    index += *iPtr;
+	    key = (VOID *) Tcl_GetHashKey (tablePtr, hPtr);
+
+#if TCL_HASH_KEY_STORE_HASH
+	    if (typePtr->hashKeyProc == NULL
+		|| typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) {
+		index = RANDOM_INDEX (tablePtr, hPtr->hash);
+	    } else {
+		index = ((unsigned int) hPtr->hash) & tablePtr->mask;
+	    }
+	    hPtr->nextPtr = tablePtr->buckets[index];
+	    tablePtr->buckets[index] = hPtr;
+#else
+	    if (typePtr->hashKeyProc) {
+		unsigned int hash;
+		hash = typePtr->hashKeyProc (tablePtr, (VOID *) key);
+		if (typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) {
+		    index = RANDOM_INDEX (tablePtr, hash);
+		} else {
+		    index = hash & tablePtr->mask;
 		}
-		index = RANDOM_INDEX(tablePtr, index);
+	    } else {
+		index = RANDOM_INDEX (tablePtr, key);
 	    }
+
 	    hPtr->bucketPtr = &(tablePtr->buckets[index]);
 	    hPtr->nextPtr = *hPtr->bucketPtr;
 	    *hPtr->bucketPtr = hPtr;
+#endif
 	}
     }
 
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 5edf6f1..b513b45 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclInt.h,v 1.45 2000/05/26 08:51:44 hobbs Exp $
+ * RCS: @(#) $Id: tclInt.h,v 1.46 2000/07/19 22:15:30 ericm Exp $
  */
 
 #ifndef _TCLINT
@@ -1540,6 +1540,15 @@ extern Tcl_ObjType	tclProcBodyType;
 extern Tcl_ObjType	tclStringType;
 
 /*
+ * Variables denoting the hash key types defined in the core.
+ */
+
+extern Tcl_HashKeyType tclArrayHashKeyType;
+extern Tcl_HashKeyType tclOneWordHashKeyType;
+extern Tcl_HashKeyType tclStringHashKeyType;
+extern Tcl_HashKeyType tclObjHashKeyType;
+
+/*
  * The head of the list of free Tcl objects, and the total number of Tcl
  * objects ever allocated and freed.
  */
diff --git a/generic/tclObj.c b/generic/tclObj.c
index ab46fe6..56555e1 100644
--- a/generic/tclObj.c
+++ b/generic/tclObj.c
@@ -1,5 +1,5 @@
 /* 
- * tclObj.c --
+ * Obj.c --
  *
  *	This file contains Tcl object-related procedures that are used by
  * 	many Tcl commands.
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclObj.c,v 1.14 2000/05/26 08:51:45 hobbs Exp $
+ * RCS: @(#) $Id: tclObj.c,v 1.15 2000/07/19 22:15:30 ericm Exp $
  */
 
 #include "tclInt.h"
@@ -36,7 +36,7 @@ Tcl_Obj *tclFreeObjList = NULL;
  */
 
 #ifdef TCL_THREADS
-Tcl_Mutex tclObjMutex;
+Tcl_Mutex ObjMutex;
 #endif
 
 /*
@@ -54,9 +54,9 @@ char *tclEmptyStringRep = &emptyString;
  */
 
 #ifdef TCL_COMPILE_STATS
-long tclObjsAlloced = 0;
-long tclObjsFreed = 0;
-long tclObjsShared[TCL_MAX_SHARED_OBJ_STATS] = { 0, 0, 0, 0, 0 };
+long ObjsAlloced = 0;
+long ObjsFreed = 0;
+long ObjsShared[TCL_MAX_SHARED_OBJ_STATS] = { 0, 0, 0, 0, 0 };
 #endif /* TCL_COMPILE_STATS */
 
 /*
@@ -74,6 +74,20 @@ static void		UpdateStringOfDouble _ANSI_ARGS_((Tcl_Obj *objPtr));
 static void		UpdateStringOfInt _ANSI_ARGS_((Tcl_Obj *objPtr));
 
 /*
+ * Prototypes for the array hash key methods.
+ */
+
+static Tcl_HashEntry *	AllocObjEntry _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr, VOID *keyPtr));
+static int		CompareObjKeys _ANSI_ARGS_((
+			    VOID *keyPtr, Tcl_HashEntry *hPtr));
+static void		FreeObjEntry _ANSI_ARGS_((
+			    Tcl_HashEntry *hPtr));
+static unsigned int	HashObjKey _ANSI_ARGS_((
+			    Tcl_HashTable *tablePtr,
+			    VOID *keyPtr));
+
+/*
  * The structures below defines the Tcl object types defined in this file by
  * means of procedures that can be invoked by generic object code. See also
  * tclStringObj.c, tclListObj.c, tclByteCode.c for other type manager
@@ -103,6 +117,18 @@ Tcl_ObjType tclIntType = {
     UpdateStringOfInt,			/* updateStringProc */
     SetIntFromAny			/* setFromAnyProc */
 };
+
+/*
+ * The structure below defines the Tcl obj hash key type.
+ */
+Tcl_HashKeyType tclObjHashKeyType = {
+    TCL_HASH_KEY_TYPE_VERSION,		/* version */
+    0,					/* flags */
+    HashObjKey,				/* hashKeyProc */
+    CompareObjKeys,			/* compareKeysProc */
+    AllocObjEntry,			/* allocEntryProc */
+    FreeObjEntry			/* freeEntryProc */
+};
 
 /*
  *-------------------------------------------------------------------------
@@ -141,16 +167,16 @@ TclInitObjSubsystem()
     Tcl_RegisterObjType(&tclProcBodyType);
 
 #ifdef TCL_COMPILE_STATS
-    Tcl_MutexLock(&tclObjMutex);
-    tclObjsAlloced = 0;
-    tclObjsFreed = 0;
+    Tcl_MutexLock(&ObjMutex);
+    ObjsAlloced = 0;
+    ObjsFreed = 0;
     {
 	int i;
 	for (i = 0;  i < TCL_MAX_SHARED_OBJ_STATS;  i++) {
-	    tclObjsShared[i] = 0;
+	    ObjsShared[i] = 0;
 	}
     }
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexUnlock(&ObjMutex);
 #endif
 }
 
@@ -181,9 +207,9 @@ TclFinalizeCompExecEnv()
         typeTableInitialized = 0;
     }
     Tcl_MutexUnlock(&tableMutex);
-    Tcl_MutexLock(&tclObjMutex);
+    Tcl_MutexLock(&ObjMutex);
     tclFreeObjList = NULL;
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexUnlock(&ObjMutex);
 
     TclFinalizeCompilation();
     TclFinalizeExecution();
@@ -389,7 +415,7 @@ Tcl_ConvertToType(interp, objPtr, typePtr)
  *
  * Side effects:
  *	If compiling with TCL_COMPILE_STATS, this procedure increments
- *	the global count of allocated objects (tclObjsAlloced).
+ *	the global count of allocated objects (ObjsAlloced).
  *
  *----------------------------------------------------------------------
  */
@@ -415,7 +441,7 @@ Tcl_NewObj()
      * we maintain.
      */
 
-    Tcl_MutexLock(&tclObjMutex);
+    Tcl_MutexLock(&ObjMutex);
     if (tclFreeObjList == NULL) {
 	TclAllocateFreeObjects();
     }
@@ -427,9 +453,9 @@ Tcl_NewObj()
     objPtr->length   = 0;
     objPtr->typePtr  = NULL;
 #ifdef TCL_COMPILE_STATS
-    tclObjsAlloced++;
+    ObjsAlloced++;
 #endif /* TCL_COMPILE_STATS */
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexUnlock(&ObjMutex);
     return objPtr;
 }
 #endif /* TCL_MEM_DEBUG */
@@ -456,7 +482,7 @@ Tcl_NewObj()
  *
  * Side effects:
  *	If compiling with TCL_COMPILE_STATS, this procedure increments
- *	the global count of allocated objects (tclObjsAlloced).
+ *	the global count of allocated objects (ObjsAlloced).
  *
  *----------------------------------------------------------------------
  */
@@ -484,9 +510,9 @@ Tcl_DbNewObj(file, line)
     objPtr->length   = 0;
     objPtr->typePtr  = NULL;
 #ifdef TCL_COMPILE_STATS
-    Tcl_MutexLock(&tclObjMutex);
-    tclObjsAlloced++;
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexLock(&ObjMutex);
+    ObjsAlloced++;
+    Tcl_MutexUnlock(&ObjMutex);
 #endif /* TCL_COMPILE_STATS */
     return objPtr;
 }
@@ -572,7 +598,7 @@ TclAllocateFreeObjects()
  *	type-specific Tcl_FreeInternalRepProc to deallocate the object's
  *	internal representation. If compiling with TCL_COMPILE_STATS,
  *	this procedure increments the global count of freed objects
- *	(tclObjsFreed).
+ *	(ObjsFreed).
  *
  *----------------------------------------------------------------------
  */
@@ -600,7 +626,7 @@ TclFreeObj(objPtr)
      * Tcl_Obj structs we maintain.
      */
 
-    Tcl_MutexLock(&tclObjMutex);
+    Tcl_MutexLock(&ObjMutex);
 #ifdef TCL_MEM_DEBUG
     ckfree((char *) objPtr);
 #else
@@ -609,9 +635,9 @@ TclFreeObj(objPtr)
 #endif /* TCL_MEM_DEBUG */
 
 #ifdef TCL_COMPILE_STATS
-    tclObjsFreed++;
+    ObjsFreed++;
 #endif /* TCL_COMPILE_STATS */
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexUnlock(&ObjMutex);
 }
 
 /*
@@ -2086,15 +2112,219 @@ Tcl_DbIsShared(objPtr, file, line)
     }
 #endif
 #ifdef TCL_COMPILE_STATS
-    Tcl_MutexLock(&tclObjMutex);
+    Tcl_MutexLock(&ObjMutex);
     if ((objPtr)->refCount <= 1) {
-	tclObjsShared[1]++;
+	ObjsShared[1]++;
     } else if ((objPtr)->refCount < TCL_MAX_SHARED_OBJ_STATS) {
-	tclObjsShared[(objPtr)->refCount]++;
+	ObjsShared[(objPtr)->refCount]++;
     } else {
-	tclObjsShared[0]++;
+	ObjsShared[0]++;
     }
-    Tcl_MutexUnlock(&tclObjMutex);
+    Tcl_MutexUnlock(&ObjMutex);
 #endif
     return ((objPtr)->refCount > 1);
 }
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_InitObjHashTable --
+ *
+ *	Given storage for a hash table, set up the fields to prepare
+ *	the hash table for use, the keys are Tcl_Obj *.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	TablePtr is now ready to be passed to Tcl_FindHashEntry and
+ *	Tcl_CreateHashEntry.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_InitObjHashTable(tablePtr)
+    register Tcl_HashTable *tablePtr;	/* Pointer to table record, which
+					 * is supplied by the caller. */
+{
+    Tcl_InitHashTableEx (tablePtr, TCL_CUSTOM_PTR_KEYS, &tclObjHashKeyType);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * AllocObjEntry --
+ *
+ *	Allocate space for a Tcl_HashEntry containing the Tcl_Obj * key.
+ *
+ * Results:
+ *	The return value is a pointer to the created entry.
+ *
+ * Side effects:
+ *	Increments the reference count on the object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static Tcl_HashEntry *
+AllocObjEntry(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key to store in the hash table entry. */
+{
+    Tcl_Obj *objPtr = (Tcl_Obj *) keyPtr;
+    Tcl_HashEntry *hPtr;
+
+    hPtr = (Tcl_HashEntry *) ckalloc((unsigned) (sizeof(Tcl_HashEntry)));
+    hPtr->key.oneWordValue = (char *) objPtr;
+    Tcl_IncrRefCount (objPtr);
+
+    return hPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CompareObjKeys --
+ *
+ *	Compares two Tcl_Obj * keys.
+ *
+ * Results:
+ *	The return value is 0 if they are different and 1 if they are
+ *	the same.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+CompareObjKeys(keyPtr, hPtr)
+    VOID *keyPtr;		/* New key to compare. */
+    Tcl_HashEntry *hPtr;		/* Existing key to compare. */
+{
+    Tcl_Obj *objPtr1 = (Tcl_Obj *) keyPtr;
+    Tcl_Obj *objPtr2 = (Tcl_Obj *) hPtr->key.oneWordValue;
+    register CONST char *p1, *p2;
+    register int l1, l2;
+
+    /*
+     * If the object pointers are the same then they match.
+     */
+    if (objPtr1 == objPtr2) {
+	return 1;
+    }
+
+    /*
+     * Don't use Tcl_GetStringFromObj as it would prevent l1 and l2 being
+     * in a register.
+     */
+    p1 = Tcl_GetString (objPtr1);
+    l1 = objPtr1->length;
+    p2 = Tcl_GetString (objPtr2);
+    l2 = objPtr2->length;
+    
+    /*
+     * Only compare if the string representations are of the same length.
+     */
+    if (l1 == l2) {
+	for (;; p1++, p2++, l1--) {
+	    if (*p1 != *p2) {
+		break;
+	    }
+	    if (l1 == 0) {
+		return 1;
+	    }
+	}
+    }
+
+    return 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * FreeObjEntry --
+ *
+ *	Frees space for a Tcl_HashEntry containing the Tcl_Obj * key.
+ *
+ * Results:
+ *	The return value is a pointer to the created entry.
+ *
+ * Side effects:
+ *	Decrements the reference count of the object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+FreeObjEntry(hPtr)
+    Tcl_HashEntry *hPtr;	/* Hash entry to free. */
+{
+    Tcl_Obj *objPtr = (Tcl_Obj *) hPtr->key.oneWordValue;
+
+    Tcl_DecrRefCount (objPtr);
+    ckfree ((char *) hPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * HashObjKey --
+ *
+ *	Compute a one-word summary of the string representation of the
+ *	Tcl_Obj, which can be used to generate a hash index.
+ *
+ * Results:
+ *	The return value is a one-word summary of the information in
+ *	the string representation of the Tcl_Obj.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static unsigned int
+HashObjKey(tablePtr, keyPtr)
+    Tcl_HashTable *tablePtr;	/* Hash table. */
+    VOID *keyPtr;		/* Key from which to compute hash value. */
+{
+    Tcl_Obj *objPtr = (Tcl_Obj *) keyPtr;
+    register CONST char *string;
+    register int length;
+    register unsigned int result;
+    register int c;
+
+    string = Tcl_GetString (objPtr);
+    length = objPtr->length;
+    
+    /*
+     * I tried a zillion different hash functions and asked many other
+     * people for advice.  Many people had their own favorite functions,
+     * all different, but no-one had much idea why they were good ones.
+     * I chose the one below (multiply by 9 and add new character)
+     * because of the following reasons:
+     *
+     * 1. Multiplying by 10 is perfect for keys that are decimal strings,
+     *    and multiplying by 9 is just about as good.
+     * 2. Times-9 is (shift-left-3) plus (old).  This means that each
+     *    character's bits hang around in the low-order bits of the
+     *    hash value for ever, plus they spread fairly rapidly up to
+     *    the high-order bits to fill out the hash value.  This seems
+     *    works well both for decimal and non-decimal strings.
+     */
+
+    result = 0;
+    while (length) {
+	c = *string;
+	string++;
+	length--;
+	if (length == 0) {
+	    break;
+	}
+	result += (result<<3) + c;
+    }
+    return result;
+}
diff --git a/generic/tclStubInit.c b/generic/tclStubInit.c
index 93a680c..ad68ecf 100644
--- a/generic/tclStubInit.c
+++ b/generic/tclStubInit.c
@@ -8,7 +8,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclStubInit.c,v 1.38 2000/05/19 21:30:16 hobbs Exp $
+ * RCS: @(#) $Id: tclStubInit.c,v 1.39 2000/07/19 22:15:31 ericm Exp $
  */
 
 #include "tclInt.h"
@@ -31,6 +31,10 @@
 #undef Tcl_NewStringObj
 #undef Tcl_DumpActiveMemory
 #undef Tcl_ValidateAllMemory
+#if TCL_PRESERVE_BINARY_COMPATABILITY
+#   undef Tcl_FindHashEntry
+#   undef Tcl_CreateHashEntry
+#endif
 
 /*
  * WARNING: The contents of this file is automatically generated by the
@@ -801,6 +805,10 @@ TclStubs tclStubs = {
     Tcl_IsChannelExisting, /* 400 */
     Tcl_UniCharNcasecmp, /* 401 */
     Tcl_UniCharCaseMatch, /* 402 */
+    Tcl_FindHashEntry, /* 403 */
+    Tcl_CreateHashEntry, /* 404 */
+    Tcl_InitHashTableEx, /* 405 */
+    Tcl_InitObjHashTable, /* 406 */
 };
 
 /* !END!: Do not edit above this line. */