diff options
Diffstat (limited to 'generic/tclHash.c')
| -rw-r--r-- | generic/tclHash.c | 790 |
1 files changed, 350 insertions, 440 deletions
diff --git a/generic/tclHash.c b/generic/tclHash.c index ae2eca8..90be511 100644 --- a/generic/tclHash.c +++ b/generic/tclHash.c @@ -1,4 +1,4 @@ -/* +/* * tclHash.c -- * * Implementation of in-memory hash tables for Tcl and Tcl-based @@ -7,10 +7,8 @@ * Copyright (c) 1991-1993 The Regents of the University of California. * Copyright (c) 1994 Sun Microsystems, Inc. * - * 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 1.12.2.1 2004/11/11 01:18:07 das Exp $ + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. */ #include "tclInt.h" @@ -19,84 +17,69 @@ * Prevent macros from clashing with function definitions. */ -#if TCL_PRESERVE_BINARY_COMPATABILITY -# undef Tcl_FindHashEntry -# undef Tcl_CreateHashEntry -#endif +#undef Tcl_FindHashEntry +#undef Tcl_CreateHashEntry /* - * When there are this many entries per bucket, on average, rebuild - * the hash table to make it larger. + * 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 - * to make it so that preliminary values that are arbitrarily similar - * will end up in different buckets. The hash function was taken - * from a random-number generator. + * The following macro takes a preliminary integer hash value and produces an + * index into a hash tables bucket list. The idea is to make it so that + * preliminary values that are arbitrarily similar will end up in different + * buckets. The hash function was taken from a random-number generator. */ #define RANDOM_INDEX(tablePtr, i) \ - (((((long) (i))*1103515245) >> (tablePtr)->downShift) & (tablePtr)->mask) + ((((i)*1103515245L) >> (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)); +static Tcl_HashEntry * AllocArrayEntry(Tcl_HashTable *tablePtr, void *keyPtr); +static int CompareArrayKeys(void *keyPtr, Tcl_HashEntry *hPtr); +static unsigned int HashArrayKey(Tcl_HashTable *tablePtr, void *keyPtr); /* - * Prototypes for the one word hash key methods. + * Prototypes for the one word hash key methods. Not actually declared because + * this is a critical path that is implemented in the core hash table access + * function. */ #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, - VOID *keyPtr)); +static Tcl_HashEntry * AllocOneWordEntry(Tcl_HashTable *tablePtr, + void *keyPtr); +static int CompareOneWordKeys(void *keyPtr, Tcl_HashEntry *hPtr); +static unsigned int HashOneWordKey(Tcl_HashTable *tablePtr, void *keyPtr); #endif /* * 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)); +static Tcl_HashEntry * AllocStringEntry(Tcl_HashTable *tablePtr, + void *keyPtr); +static int CompareStringKeys(void *keyPtr, Tcl_HashEntry *hPtr); +static unsigned int HashStringKey(Tcl_HashTable *tablePtr, void *keyPtr); /* - * Procedure prototypes for static procedures in this file: + * Function prototypes for static functions in this file: */ -#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)); -#endif - -static void RebuildTable _ANSI_ARGS_((Tcl_HashTable *tablePtr)); +static Tcl_HashEntry * BogusFind(Tcl_HashTable *tablePtr, const char *key); +static Tcl_HashEntry * BogusCreate(Tcl_HashTable *tablePtr, const char *key, + int *newPtr); +static Tcl_HashEntry * CreateHashEntry(Tcl_HashTable *tablePtr, const char *key, + int *newPtr); +static Tcl_HashEntry * FindHashEntry(Tcl_HashTable *tablePtr, const char *key); +static void RebuildTable(Tcl_HashTable *tablePtr); -Tcl_HashKeyType tclArrayHashKeyType = { +const Tcl_HashKeyType tclArrayHashKeyType = { TCL_HASH_KEY_TYPE_VERSION, /* version */ TCL_HASH_KEY_RANDOMIZE_HASH, /* flags */ HashArrayKey, /* hashKeyProc */ @@ -105,7 +88,7 @@ Tcl_HashKeyType tclArrayHashKeyType = { NULL /* freeEntryProc */ }; -Tcl_HashKeyType tclOneWordHashKeyType = { +const Tcl_HashKeyType tclOneWordHashKeyType = { TCL_HASH_KEY_TYPE_VERSION, /* version */ 0, /* flags */ NULL, /* HashOneWordKey, */ /* hashProc */ @@ -114,7 +97,7 @@ Tcl_HashKeyType tclOneWordHashKeyType = { NULL /* FreeOneWordKey, */ /* freeEntryProc */ }; -Tcl_HashKeyType tclStringHashKeyType = { +const Tcl_HashKeyType tclStringHashKeyType = { TCL_HASH_KEY_TYPE_VERSION, /* version */ 0, /* flags */ HashStringKey, /* hashKeyProc */ @@ -122,15 +105,14 @@ Tcl_HashKeyType tclStringHashKeyType = { AllocStringEntry, /* allocEntryProc */ NULL /* freeEntryProc */ }; - /* *---------------------------------------------------------------------- * * Tcl_InitHashTable -- * - * Given storage for a hash table, set up the fields to prepare - * the hash table for use. + * Given storage for a hash table, set up the fields to prepare the hash + * table for use. * * Results: * None. @@ -142,22 +124,23 @@ Tcl_HashKeyType tclStringHashKeyType = { *---------------------------------------------------------------------- */ -#undef Tcl_InitHashTable void -Tcl_InitHashTable(tablePtr, keyType) - 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, - * or an integer >= 2. */ +Tcl_InitHashTable( + 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, 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. + * 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_InitCustomHashTable(tablePtr, keyType, (Tcl_HashKeyType *) -1); + + Tcl_InitCustomHashTable(tablePtr, keyType, (const Tcl_HashKeyType *) -1); } /* @@ -165,9 +148,9 @@ Tcl_InitHashTable(tablePtr, keyType) * * Tcl_InitCustomHashTable -- * - * Given storage for a hash table, set up the fields to prepare - * the hash table for use. This is an extended version of - * Tcl_InitHashTable which supports user defined keys. + * Given storage for a hash table, set up the fields to prepare the hash + * table for use. This is an extended version of Tcl_InitHashTable which + * supports user defined keys. * * Results: * None. @@ -180,22 +163,22 @@ Tcl_InitHashTable(tablePtr, keyType) */ void -Tcl_InitCustomHashTable(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. */ +Tcl_InitCustomHashTable( + 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. */ + const Tcl_HashKeyType *typePtr) /* Pointer to structure which defines the + * behaviour of this table. */ { -#if (TCL_SMALL_HASH_TABLE != 4) - panic("Tcl_InitCustomHashTable: TCL_SMALL_HASH_TABLE is %d, not 4\n", +#if (TCL_SMALL_HASH_TABLE != 4) + Tcl_Panic("Tcl_InitCustomHashTable: TCL_SMALL_HASH_TABLE is %d, not 4", TCL_SMALL_HASH_TABLE); #endif - + tablePtr->buckets = tablePtr->staticBuckets; tablePtr->staticBuckets[0] = tablePtr->staticBuckets[1] = 0; tablePtr->staticBuckets[2] = tablePtr->staticBuckets[3] = 0; @@ -205,9 +188,8 @@ Tcl_InitCustomHashTable(tablePtr, keyType, typePtr) tablePtr->downShift = 28; tablePtr->mask = 3; tablePtr->keyType = keyType; -#if TCL_PRESERVE_BINARY_COMPATABILITY - tablePtr->findProc = Tcl_FindHashEntry; - tablePtr->createProc = Tcl_CreateHashEntry; + tablePtr->findProc = FindHashEntry; + tablePtr->createProc = CreateHashEntry; if (typePtr == NULL) { /* @@ -216,41 +198,16 @@ Tcl_InitCustomHashTable(tablePtr, keyType, typePtr) */ } else if (typePtr != (Tcl_HashKeyType *) -1) { /* - * The caller is requesting a customized hash table so it must be - * an extended version. + * 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. + * 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 } /* @@ -261,8 +218,8 @@ Tcl_InitCustomHashTable(tablePtr, keyType, typePtr) * 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. + * 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. @@ -271,94 +228,36 @@ Tcl_InitCustomHashTable(tablePtr, keyType, typePtr) */ 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. */ +Tcl_FindHashEntry( + Tcl_HashTable *tablePtr, /* Table in which to lookup entry. */ + const void *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 { - 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. - */ + return (*((tablePtr)->findProc))(tablePtr, key); +} - if (typePtr->compareKeysProc) { - Tcl_CompareHashKeysProc *compareKeysProc = 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 (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; +static Tcl_HashEntry * +FindHashEntry( + Tcl_HashTable *tablePtr, /* Table in which to lookup entry. */ + const char *key) /* Key to use to find matching entry. */ +{ + return CreateHashEntry(tablePtr, key, 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. + * 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. + * 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. @@ -367,47 +266,50 @@ Tcl_FindHashEntry(tablePtr, key) */ 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 +Tcl_CreateHashEntry( + Tcl_HashTable *tablePtr, /* Table in which to lookup entry. */ + const void *key, /* Key to use to find or create matching + * entry. */ + int *newPtr) /* Store info here telling whether a new entry + * was created. */ +{ + return (*((tablePtr)->createProc))(tablePtr, key, newPtr); +} + +static Tcl_HashEntry * +CreateHashEntry( + 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. */ + int *newPtr) /* Store info here telling whether a new entry + * was created. */ { register Tcl_HashEntry *hPtr; - Tcl_HashKeyType *typePtr; + const 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) { + || 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); + hash = typePtr->hashKeyProc(tablePtr, (void *) key); if (typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) { - index = RANDOM_INDEX (tablePtr, hash); + index = RANDOM_INDEX(tablePtr, hash); } else { index = hash & tablePtr->mask; } } else { - hash = (unsigned int) key; - index = RANDOM_INDEX (tablePtr, hash); + hash = PTR2UINT(key); + index = RANDOM_INDEX(tablePtr, hash); } /* @@ -416,65 +318,70 @@ Tcl_CreateHashEntry(tablePtr, key, newPtr) if (typePtr->compareKeysProc) { Tcl_CompareHashKeysProc *compareKeysProc = typePtr->compareKeysProc; + for (hPtr = tablePtr->buckets[index]; hPtr != NULL; - hPtr = hPtr->nextPtr) { + hPtr = hPtr->nextPtr) { #if TCL_HASH_KEY_STORE_HASH - if (hash != (unsigned int) hPtr->hash) { + if (hash != PTR2UINT(hPtr->hash)) { continue; } #endif - if (compareKeysProc ((VOID *) key, hPtr)) { - *newPtr = 0; + if (compareKeysProc((void *) key, hPtr)) { + if (newPtr) { + *newPtr = 0; + } return hPtr; } } } else { for (hPtr = tablePtr->buckets[index]; hPtr != NULL; - hPtr = hPtr->nextPtr) { + hPtr = hPtr->nextPtr) { #if TCL_HASH_KEY_STORE_HASH - if (hash != (unsigned int) hPtr->hash) { + if (hash != PTR2UINT(hPtr->hash)) { continue; } #endif if (key == hPtr->key.oneWordValue) { - *newPtr = 0; + if (newPtr) { + *newPtr = 0; + } return hPtr; } } } + if (!newPtr) { + return NULL; + } + /* - * Entry not found. Add a new one to the bucket. + * Entry not found. Add a new one to the bucket. */ *newPtr = 1; if (typePtr->allocEntryProc) { - hPtr = typePtr->allocEntryProc (tablePtr, (VOID *) key); + hPtr = typePtr->allocEntryProc(tablePtr, (void *) key); } else { - hPtr = (Tcl_HashEntry *) ckalloc((unsigned) sizeof(Tcl_HashEntry)); + hPtr = ckalloc(sizeof(Tcl_HashEntry)); hPtr->key.oneWordValue = (char *) key; + hPtr->clientData = 0; } - + hPtr->tablePtr = tablePtr; #if TCL_HASH_KEY_STORE_HASH -# if TCL_PRESERVE_BINARY_COMPATABILITY - hPtr->hash = (VOID *) hash; -# else - hPtr->hash = hash; -# endif + hPtr->hash = UINT2PTR(hash); hPtr->nextPtr = tablePtr->buckets[index]; tablePtr->buckets[index] = hPtr; #else - hPtr->bucketPtr = &(tablePtr->buckets[index]); + 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 the table has exceeded a decent size, rebuild it with many more + * buckets. */ if (tablePtr->numEntries >= tablePtr->rebuildSize) { @@ -494,20 +401,19 @@ Tcl_CreateHashEntry(tablePtr, key, newPtr) * None. * * Side effects: - * The entry given by entryPtr is deleted from its table and - * should never again be used by the caller. It is up to the - * caller to free the clientData field of the entry, if that - * is relevant. + * The entry given by entryPtr is deleted from its table and should never + * again be used by the caller. It is up to the caller to free the + * clientData field of the entry, if that is relevant. * *---------------------------------------------------------------------- */ void -Tcl_DeleteHashEntry(entryPtr) - Tcl_HashEntry *entryPtr; +Tcl_DeleteHashEntry( + Tcl_HashEntry *entryPtr) { register Tcl_HashEntry *prevPtr; - Tcl_HashKeyType *typePtr; + const Tcl_HashKeyType *typePtr; Tcl_HashTable *tablePtr; Tcl_HashEntry **bucketPtr; #if TCL_HASH_KEY_STORE_HASH @@ -516,40 +422,36 @@ Tcl_DeleteHashEntry(entryPtr) tablePtr = entryPtr->tablePtr; -#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) { + || tablePtr->keyType == TCL_CUSTOM_PTR_KEYS) { typePtr = tablePtr->typePtr; } else { 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); + || typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) { + index = RANDOM_INDEX(tablePtr, PTR2INT(entryPtr->hash)); } else { - index = ((unsigned int) entryPtr->hash) & tablePtr->mask; + index = PTR2UINT(entryPtr->hash) & tablePtr->mask; } - bucketPtr = &(tablePtr->buckets[index]); + 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"); + Tcl_Panic("malformed bucket chain in Tcl_DeleteHashEntry"); } if (prevPtr->nextPtr == entryPtr) { prevPtr->nextPtr = entryPtr->nextPtr; @@ -560,9 +462,9 @@ Tcl_DeleteHashEntry(entryPtr) tablePtr->numEntries--; if (typePtr->freeEntryProc) { - typePtr->freeEntryProc (entryPtr); + typePtr->freeEntryProc(entryPtr); } else { - ckfree((char *) entryPtr); + ckfree(entryPtr); } } @@ -571,8 +473,8 @@ Tcl_DeleteHashEntry(entryPtr) * * Tcl_DeleteHashTable -- * - * Free up everything associated with a hash table except for - * the record for the table itself. + * Free up everything associated with a hash table except for the record + * for the table itself. * * Results: * None. @@ -584,27 +486,23 @@ Tcl_DeleteHashEntry(entryPtr) */ void -Tcl_DeleteHashTable(tablePtr) - register Tcl_HashTable *tablePtr; /* Table to delete. */ +Tcl_DeleteHashTable( + register Tcl_HashTable *tablePtr) /* Table to delete. */ { register Tcl_HashEntry *hPtr, *nextPtr; - Tcl_HashKeyType *typePtr; + const 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) { + || 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. @@ -615,9 +513,9 @@ Tcl_DeleteHashTable(tablePtr) while (hPtr != NULL) { nextPtr = hPtr->nextPtr; if (typePtr->freeEntryProc) { - typePtr->freeEntryProc (hPtr); + typePtr->freeEntryProc(hPtr); } else { - ckfree((char *) hPtr); + ckfree(hPtr); } hPtr = nextPtr; } @@ -628,7 +526,11 @@ Tcl_DeleteHashTable(tablePtr) */ if (tablePtr->buckets != tablePtr->staticBuckets) { - ckfree((char *) tablePtr->buckets); + if (typePtr->flags & TCL_HASH_KEY_SYSTEM_HASH) { + TclpSysFree((char *) tablePtr->buckets); + } else { + ckfree(tablePtr->buckets); + } } /* @@ -636,12 +538,8 @@ Tcl_DeleteHashTable(tablePtr) * re-initialization. */ -#if TCL_PRESERVE_BINARY_COMPATABILITY tablePtr->findProc = BogusFind; tablePtr->createProc = BogusCreate; -#else - tablePtr->typePtr = NULL; -#endif } /* @@ -649,16 +547,14 @@ Tcl_DeleteHashTable(tablePtr) * * Tcl_FirstHashEntry -- * - * Locate the first entry in a hash table and set up a record - * that can be used to step through all the remaining entries - * of the table. + * Locate the first entry in a hash table and set up a record that can be + * used to step through all the remaining entries of the table. * * Results: - * The return value is a pointer to the first entry in tablePtr, - * or NULL if tablePtr has no entries in it. The memory at - * *searchPtr is initialized so that subsequent calls to - * Tcl_NextHashEntry will return all of the entries in the table, - * one at a time. + * The return value is a pointer to the first entry in tablePtr, or NULL + * if tablePtr has no entries in it. The memory at *searchPtr is + * initialized so that subsequent calls to Tcl_NextHashEntry will return + * all of the entries in the table, one at a time. * * Side effects: * None. @@ -667,10 +563,10 @@ Tcl_DeleteHashTable(tablePtr) */ Tcl_HashEntry * -Tcl_FirstHashEntry(tablePtr, searchPtr) - Tcl_HashTable *tablePtr; /* Table to search. */ - Tcl_HashSearch *searchPtr; /* Place to store information about - * progress through the table. */ +Tcl_FirstHashEntry( + Tcl_HashTable *tablePtr, /* Table to search. */ + Tcl_HashSearch *searchPtr) /* Place to store information about progress + * through the table. */ { searchPtr->tablePtr = tablePtr; searchPtr->nextIndex = 0; @@ -684,12 +580,12 @@ Tcl_FirstHashEntry(tablePtr, searchPtr) * Tcl_NextHashEntry -- * * Once a hash table enumeration has been initiated by calling - * Tcl_FirstHashEntry, this procedure may be called to return - * successive elements of the table. + * Tcl_FirstHashEntry, this function may be called to return successive + * elements of the table. * * Results: - * The return value is the next entry in the hash table being - * enumerated, or NULL if the end of the table is reached. + * The return value is the next entry in the hash table being enumerated, + * or NULL if the end of the table is reached. * * Side effects: * None. @@ -698,11 +594,12 @@ Tcl_FirstHashEntry(tablePtr, searchPtr) */ Tcl_HashEntry * -Tcl_NextHashEntry(searchPtr) - register Tcl_HashSearch *searchPtr; /* Place to store information about - * progress through the table. Must - * have been initialized by calling - * Tcl_FirstHashEntry. */ +Tcl_NextHashEntry( + register Tcl_HashSearch *searchPtr) + /* Place to store information about progress + * through the table. Must have been + * initialized by calling + * Tcl_FirstHashEntry. */ { Tcl_HashEntry *hPtr; Tcl_HashTable *tablePtr = searchPtr->tablePtr; @@ -725,13 +622,12 @@ Tcl_NextHashEntry(searchPtr) * * Tcl_HashStats -- * - * Return statistics describing the layout of the hash table - * in its hash buckets. + * Return statistics describing the layout of the hash table in its hash + * buckets. * * Results: - * The return value is a malloc-ed string containing information - * about tablePtr. It is the caller's responsibility to free - * this string. + * The return value is a malloc-ed string containing information about + * tablePtr. It is the caller's responsibility to free this string. * * Side effects: * None. @@ -739,9 +635,9 @@ Tcl_NextHashEntry(searchPtr) *---------------------------------------------------------------------- */ -CONST char * -Tcl_HashStats(tablePtr) - Tcl_HashTable *tablePtr; /* Table for which to produce stats. */ +char * +Tcl_HashStats( + Tcl_HashTable *tablePtr) /* Table for which to produce stats. */ { #define NUM_COUNTERS 10 int count[NUM_COUNTERS], overflow, i, j; @@ -769,14 +665,16 @@ Tcl_HashStats(tablePtr) overflow++; } tmp = j; - average += (tmp+1.0)*(tmp/tablePtr->numEntries)/2.0; + if (tablePtr->numEntries != 0) { + average += (tmp+1.0)*(tmp/tablePtr->numEntries)/2.0; + } } /* * Print out the histogram and a few other pieces of information. */ - result = (char *) ckalloc((unsigned) ((NUM_COUNTERS*60) + 300)); + result = ckalloc((NUM_COUNTERS * 60) + 300); sprintf(result, "%d entries in table, %d buckets\n", tablePtr->numEntries, tablePtr->numBuckets); p = result + strlen(result); @@ -809,9 +707,9 @@ Tcl_HashStats(tablePtr) */ static Tcl_HashEntry * -AllocArrayEntry(tablePtr, keyPtr) - Tcl_HashTable *tablePtr; /* Hash table. */ - VOID *keyPtr; /* Key to store in the hash table entry. */ +AllocArrayEntry( + Tcl_HashTable *tablePtr, /* Hash table. */ + void *keyPtr) /* Key to store in the hash table entry. */ { int *array = (int *) keyPtr; register int *iPtr1, *iPtr2; @@ -820,16 +718,18 @@ AllocArrayEntry(tablePtr, keyPtr) unsigned int size; count = tablePtr->keyType; - + size = sizeof(Tcl_HashEntry) + (count*sizeof(int)) - sizeof(hPtr->key); - if (size < sizeof(Tcl_HashEntry)) + if (size < sizeof(Tcl_HashEntry)) { size = sizeof(Tcl_HashEntry); - hPtr = (Tcl_HashEntry *) ckalloc(size); - + } + hPtr = ckalloc(size); + for (iPtr1 = array, iPtr2 = hPtr->key.words; count > 0; count--, iPtr1++, iPtr2++) { *iPtr2 = *iPtr1; } + hPtr->clientData = 0; return hPtr; } @@ -842,8 +742,8 @@ AllocArrayEntry(tablePtr, keyPtr) * Compares two array keys. * * Results: - * The return value is 0 if they are different and 1 if they are - * the same. + * The return value is 0 if they are different and 1 if they are the + * same. * * Side effects: * None. @@ -852,12 +752,12 @@ AllocArrayEntry(tablePtr, keyPtr) */ static int -CompareArrayKeys(keyPtr, hPtr) - VOID *keyPtr; /* New key to compare. */ - Tcl_HashEntry *hPtr; /* Existing key to compare. */ +CompareArrayKeys( + void *keyPtr, /* New key to compare. */ + Tcl_HashEntry *hPtr) /* Existing key to compare. */ { - register CONST int *iPtr1 = (CONST int *) keyPtr; - register CONST int *iPtr2 = (CONST int *) hPtr->key.words; + register const int *iPtr1 = (const int *) keyPtr; + register const int *iPtr2 = (const int *) hPtr->key.words; Tcl_HashTable *tablePtr = hPtr->tablePtr; int count; @@ -877,8 +777,8 @@ CompareArrayKeys(keyPtr, hPtr) * * HashArrayKey -- * - * Compute a one-word summary of an array, which can be - * used to generate a hash index. + * Compute a one-word summary of an array, which can be used to generate + * a hash index. * * Results: * The return value is a one-word summary of the information in @@ -891,11 +791,11 @@ CompareArrayKeys(keyPtr, hPtr) */ static unsigned int -HashArrayKey(tablePtr, keyPtr) - Tcl_HashTable *tablePtr; /* Hash table. */ - VOID *keyPtr; /* Key from which to compute hash value. */ +HashArrayKey( + Tcl_HashTable *tablePtr, /* Hash table. */ + void *keyPtr) /* Key from which to compute hash value. */ { - register CONST int *array = (CONST int *) keyPtr; + register const int *array = (const int *) keyPtr; register unsigned int result; int count; @@ -923,20 +823,21 @@ HashArrayKey(tablePtr, keyPtr) */ static Tcl_HashEntry * -AllocStringEntry(tablePtr, keyPtr) - Tcl_HashTable *tablePtr; /* Hash table. */ - VOID *keyPtr; /* Key to store in the hash table entry. */ +AllocStringEntry( + Tcl_HashTable *tablePtr, /* Hash table. */ + void *keyPtr) /* Key to store in the hash table entry. */ { - CONST char *string = (CONST char *) keyPtr; + const char *string = (const char *) keyPtr; Tcl_HashEntry *hPtr; - unsigned int size; - - size = sizeof(Tcl_HashEntry) + strlen(string) + 1 - sizeof(hPtr->key); - if (size < sizeof(Tcl_HashEntry)) - size = sizeof(Tcl_HashEntry); - hPtr = (Tcl_HashEntry *) ckalloc(size); - strcpy(hPtr->key.string, string); + unsigned int size, allocsize; + allocsize = size = strlen(string) + 1; + if (size < sizeof(hPtr->key)) { + allocsize = sizeof(hPtr->key); + } + hPtr = ckalloc(TclOffset(Tcl_HashEntry, key) + allocsize); + memcpy(hPtr->key.string, string, size); + hPtr->clientData = 0; return hPtr; } @@ -948,8 +849,8 @@ AllocStringEntry(tablePtr, keyPtr) * Compares two string keys. * * Results: - * The return value is 0 if they are different and 1 if they are - * the same. + * The return value is 0 if they are different and 1 if they are the + * same. * * Side effects: * None. @@ -958,22 +859,14 @@ AllocStringEntry(tablePtr, keyPtr) */ static int -CompareStringKeys(keyPtr, hPtr) - VOID *keyPtr; /* New key to compare. */ - Tcl_HashEntry *hPtr; /* Existing key to compare. */ +CompareStringKeys( + void *keyPtr, /* New key to compare. */ + Tcl_HashEntry *hPtr) /* Existing key to compare. */ { - register CONST char *p1 = (CONST char *) keyPtr; - register CONST char *p2 = (CONST char *) hPtr->key.string; + register const char *p1 = (const char *) keyPtr; + register const char *p2 = (const char *) hPtr->key.string; - for (;; p1++, p2++) { - if (*p1 != *p2) { - break; - } - if (*p1 == '\0') { - return 1; - } - } - return 0; + return !strcmp(p1, p2); } /* @@ -981,12 +874,11 @@ CompareStringKeys(keyPtr, hPtr) * * HashStringKey -- * - * Compute a one-word summary of a text string, 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 - * string. + * The return value is a one-word summary of the information in string. * * Side effects: * None. @@ -994,55 +886,65 @@ CompareStringKeys(keyPtr, hPtr) *---------------------------------------------------------------------- */ -static unsigned int -HashStringKey(tablePtr, keyPtr) - Tcl_HashTable *tablePtr; /* Hash table. */ - VOID *keyPtr; /* Key from which to compute hash value. */ +static unsigned +HashStringKey( + Tcl_HashTable *tablePtr, /* Hash table. */ + void *keyPtr) /* Key from which to compute hash value. */ { - register CONST char *string = (CONST char *) keyPtr; + register const char *string = keyPtr; register unsigned int result; - register int c; + register char 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: + * 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, but isn't strong against maliciously-chosen + * keys. + * + * Note that this function is very weak against malicious strings; it's + * very easy to generate multiple keys that have the same hashcode. On the + * other hand, that hardly ever actually occurs and this function *is* + * very cheap, even by comparison with industry-standard hashes like FNV. + * If real strength of hash is required though, use a custom hash based on + * Bob Jenkins's lookup3(), but be aware that it's significantly slower. + * Since Tcl command and namespace names are usually reasonably-named (the + * main use for string hashes in modern Tcl) speed is far more important + * than strength. * - * 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. + * See also HashString in tclLiteral.c. + * See also TclObjHashKey in tclObj.c. + * + * See [tcl-Feature Request #2958832] */ - result = 0; - while (1) { - c = *string; - if (c == 0) { - break; + if ((result = UCHAR(*string)) != 0) { + while ((c = *++string) != 0) { + result += (result << 3) + UCHAR(c); } - result += (result<<3) + c; - string++; } return result; } -#if TCL_PRESERVE_BINARY_COMPATABILITY /* *---------------------------------------------------------------------- * * BogusFind -- * - * This procedure is invoked when an Tcl_FindHashEntry is called - * on a table that has been deleted. + * This function 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. + * If Tcl_Panic returns (which it shouldn't) this function returns NULL. * * Side effects: * Generates a panic. @@ -1052,11 +954,11 @@ HashStringKey(tablePtr, keyPtr) /* 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. */ +BogusFind( + 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"); + Tcl_Panic("called %s on deleted table", "Tcl_FindHashEntry"); return NULL; } @@ -1065,12 +967,11 @@ BogusFind(tablePtr, key) * * BogusCreate -- * - * This procedure is invoked when an Tcl_CreateHashEntry is called - * on a table that has been deleted. + * This function 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. + * If panic returns (which it shouldn't) this function returns NULL. * * Side effects: * Generates a panic. @@ -1080,60 +981,72 @@ BogusFind(tablePtr, key) /* 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 +BogusCreate( + 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. */ + int *newPtr) /* Store info here telling whether a new entry + * was created. */ { - panic("called Tcl_CreateHashEntry on deleted table"); + Tcl_Panic("called %s on deleted table", "Tcl_CreateHashEntry"); return NULL; } -#endif /* *---------------------------------------------------------------------- * * RebuildTable -- * - * This procedure is invoked when the ratio of entries to hash - * buckets becomes too large. It creates a new table with a - * larger bucket array and moves all of the entries into the - * new table. + * This function is invoked when the ratio of entries to hash buckets + * becomes too large. It creates a new table with a larger bucket array + * and moves all of the entries into the new table. * * Results: * None. * * Side effects: - * Memory gets reallocated and entries get re-hashed to new - * buckets. + * Memory gets reallocated and entries get re-hashed to new buckets. * *---------------------------------------------------------------------- */ static void -RebuildTable(tablePtr) - register Tcl_HashTable *tablePtr; /* Table to enlarge. */ +RebuildTable( + register Tcl_HashTable *tablePtr) /* Table to enlarge. */ { int oldSize, count, index; Tcl_HashEntry **oldBuckets; register Tcl_HashEntry **oldChainPtr, **newChainPtr; register Tcl_HashEntry *hPtr; - Tcl_HashKeyType *typePtr; - VOID *key; + const Tcl_HashKeyType *typePtr; + + 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; + } oldSize = tablePtr->numBuckets; oldBuckets = tablePtr->buckets; /* - * Allocate and initialize the new bucket array, and set up - * hashing constants for new array size. + * Allocate and initialize the new bucket array, and set up hashing + * constants for new array size. */ tablePtr->numBuckets *= 4; - tablePtr->buckets = (Tcl_HashEntry **) ckalloc((unsigned) - (tablePtr->numBuckets * sizeof(Tcl_HashEntry *))); + if (typePtr->flags & TCL_HASH_KEY_SYSTEM_HASH) { + tablePtr->buckets = (Tcl_HashEntry **) TclpSysAlloc((unsigned) + (tablePtr->numBuckets * sizeof(Tcl_HashEntry *)), 0); + } else { + tablePtr->buckets = + ckalloc(tablePtr->numBuckets * sizeof(Tcl_HashEntry *)); + } for (count = tablePtr->numBuckets, newChainPtr = tablePtr->buckets; count > 0; count--, newChainPtr++) { *newChainPtr = NULL; @@ -1142,21 +1055,6 @@ 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. */ @@ -1164,32 +1062,32 @@ RebuildTable(tablePtr) for (oldChainPtr = oldBuckets; oldSize > 0; oldSize--, oldChainPtr++) { for (hPtr = *oldChainPtr; hPtr != NULL; hPtr = *oldChainPtr) { *oldChainPtr = hPtr->nextPtr; - - 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); + || typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) { + index = RANDOM_INDEX(tablePtr, PTR2INT(hPtr->hash)); } else { - index = ((unsigned int) hPtr->hash) & tablePtr->mask; + index = PTR2UINT(hPtr->hash) & tablePtr->mask; } hPtr->nextPtr = tablePtr->buckets[index]; tablePtr->buckets[index] = hPtr; #else + void *key = Tcl_GetHashKey(tablePtr, hPtr); + if (typePtr->hashKeyProc) { unsigned int hash; - hash = typePtr->hashKeyProc (tablePtr, (VOID *) key); + + hash = typePtr->hashKeyProc(tablePtr, key); if (typePtr->flags & TCL_HASH_KEY_RANDOMIZE_HASH) { - index = RANDOM_INDEX (tablePtr, hash); + index = RANDOM_INDEX(tablePtr, hash); } else { index = hash & tablePtr->mask; } } else { - index = RANDOM_INDEX (tablePtr, key); + index = RANDOM_INDEX(tablePtr, key); } - hPtr->bucketPtr = &(tablePtr->buckets[index]); + hPtr->bucketPtr = &tablePtr->buckets[index]; hPtr->nextPtr = *hPtr->bucketPtr; *hPtr->bucketPtr = hPtr; #endif @@ -1201,6 +1099,18 @@ RebuildTable(tablePtr) */ if (oldBuckets != tablePtr->staticBuckets) { - ckfree((char *) oldBuckets); + if (typePtr->flags & TCL_HASH_KEY_SYSTEM_HASH) { + TclpSysFree((char *) oldBuckets); + } else { + ckfree(oldBuckets); + } } } + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |