diff options
Diffstat (limited to 'generic/tclObj.c')
-rw-r--r-- | generic/tclObj.c | 290 |
1 files changed, 260 insertions, 30 deletions
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; +} |