diff options
Diffstat (limited to 'generic/tclStringObj.c')
| -rw-r--r-- | generic/tclStringObj.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/generic/tclStringObj.c b/generic/tclStringObj.c index fefb014..7fd7cc1 100644 --- a/generic/tclStringObj.c +++ b/generic/tclStringObj.c @@ -2609,6 +2609,235 @@ TclGetStringStorage( *sizePtr = stringPtr->allocated; return objPtr->bytes; } + +/* + *--------------------------------------------------------------------------- + * + * TclStringCatObjv -- + * + * Performs the [string cat] function. + * + * Results: + * A standard Tcl result. + * + * Side effects: + * Writes to *objPtrPtr the address of Tcl_Obj that is concatenation + * of all objc values in objv. + * + *--------------------------------------------------------------------------- + */ + +int +TclStringCatObjv( + Tcl_Interp *interp, + int inPlace, + int objc, + Tcl_Obj * const objv[], + Tcl_Obj **objPtrPtr) +{ + Tcl_Obj *objPtr, *objResultPtr, * const *ov; + int oc, length = 0, binary = 1, first = 0; + int allowUniChar = 1, requestUniChar = 0; + + /* assert (objc >= 2) */ + + /* + * Analyze to determine what representation result should be. + * GOALS: Avoid shimmering & string rep generation. + * Produce pure bytearray when possible. + * Error on overflow. + */ + + ov = objv, oc = objc; + while (oc-- && (binary || allowUniChar)) { + objPtr = *ov++; + + if (objPtr->bytes) { + /* Value has a string rep. */ + if (objPtr->length) { + /* + * Non-empty string rep. Not a pure bytearray, so we + * won't create a pure bytearray + */ + binary = 0; + if ((objPtr->typePtr) && (objPtr->typePtr != &tclStringType)) { + /* Prevent shimmer of non-string types. */ + allowUniChar = 0; + } + } + } else { + /* assert (objPtr->typePtr != NULL) -- stork! */ + if (TclIsPureByteArray(objPtr)) { + allowUniChar = 0; + } else { + binary = 0; + if (objPtr->typePtr == &tclStringType) { + /* Have a pure Unicode value; ask to preserve it */ + requestUniChar = 1; + } else { + /* Have another type; prevent shimmer */ + allowUniChar = 0; + } + } + } + } + + if (binary) { + /* Result will be pure byte array. Pre-size it */ + ov = objv; oc = objc; + while (oc-- && (length >= 0)) { + objPtr = *ov++; + + if (objPtr->bytes == NULL) { + int numBytes; + + Tcl_GetByteArrayFromObj(objPtr, &numBytes); + if (length == 0) { + first = objc - oc - 1; + } + length += numBytes; + } + } + } else if (allowUniChar && requestUniChar) { + /* Result will be pure Tcl_UniChar array. Pre-size it. */ + ov = objv; oc = objc; + while (oc-- && (length >= 0)) { + objPtr = *ov++; + + if ((objPtr->bytes == NULL) || (objPtr->length)) { + int numChars; + + Tcl_GetUnicodeFromObj(objPtr, &numChars); + if (length == 0) { + first = objc - oc - 1; + } + length += numChars; + } + } + } else { + /* Result will be concat of string reps. Pre-size it. */ + ov = objv; oc = objc; + while (oc-- && (length >= 0)) { + int numBytes; + + objPtr = *ov++; + + Tcl_GetStringFromObj(objPtr, &numBytes); + if ((length == 0) && numBytes) { + first = objc - oc - 1; + } + length += numBytes; + } + } + + if (length < 0) { + if (interp) { + Tcl_SetObjResult(interp, Tcl_ObjPrintf( + "max size for a Tcl value (%d bytes) exceeded", INT_MAX)); + Tcl_SetErrorCode(interp, "TCL", "MEMORY", NULL); + } + return TCL_ERROR; + } + + if (length == 0) { + /* Total length of zero means every value has length zero */ + *objPtrPtr = objv[0]; + return TCL_OK; + } + + objv += first; objc -= first; + + if (binary) { + /* Efficiently produce a pure byte array result */ + unsigned char *dst; + + if (inPlace && !Tcl_IsShared(*objv)) { + int start; + + objResultPtr = *objv++; objc--; + Tcl_GetByteArrayFromObj(objResultPtr, &start); + dst = Tcl_SetByteArrayLength(objResultPtr, length) + start; + } else { + objResultPtr = Tcl_NewByteArrayObj(NULL, length); + dst = Tcl_SetByteArrayLength(objResultPtr, length); + } + while (objc--) { + Tcl_Obj *objPtr = *objv++; + + if (objPtr->bytes == NULL) { + int more; + unsigned char *src = Tcl_GetByteArrayFromObj(objPtr, &more); + memcpy(dst, src, (size_t) more); + dst += more; + } + } + } else if (allowUniChar && requestUniChar) { + /* Efficiently produce a pure Tcl_UniChar array result */ + Tcl_UniChar *dst; + + if (inPlace && !Tcl_IsShared(*objv)) { + int start; + + objResultPtr = *objv++; objc--; + + /* Ugly interface! Force resize of the unicode array. */ + Tcl_GetUnicodeFromObj(objResultPtr, &start); + Tcl_InvalidateStringRep(objResultPtr); + Tcl_SetObjLength(objResultPtr, length); + dst = Tcl_GetUnicode(objResultPtr) + start; + } else { + Tcl_UniChar ch = 0; + + /* Ugly interface! No scheme to init array size. */ + objResultPtr = Tcl_NewUnicodeObj(&ch, 0); + Tcl_SetObjLength(objResultPtr, length); + dst = Tcl_GetUnicode(objResultPtr); + } + while (objc--) { + Tcl_Obj *objPtr = *objv++; + + if ((objPtr->bytes == NULL) || (objPtr->length)) { + int more; + Tcl_UniChar *src = Tcl_GetUnicodeFromObj(objPtr, &more); + memcpy(dst, src, more * sizeof(Tcl_UniChar)); + dst += more; + } + } + } else { + /* Efficiently concatenate string reps */ + char *dst; + + if (inPlace && !Tcl_IsShared(*objv)) { + int start; + + objResultPtr = *objv++; objc--; + + Tcl_GetStringFromObj(objResultPtr, &start); + Tcl_SetObjLength(objResultPtr, length); + dst = Tcl_GetString(objResultPtr) + start; + if (length > start) { + TclFreeIntRep(objResultPtr); + } + } else { + objResultPtr = Tcl_NewObj(); + Tcl_SetObjLength(objResultPtr, length); + dst = Tcl_GetString(objResultPtr); + } + while (objc--) { + Tcl_Obj *objPtr = *objv++; + + if ((objPtr->bytes == NULL) || (objPtr->length)) { + int more; + char *src = Tcl_GetStringFromObj(objPtr, &more); + memcpy(dst, src, (size_t) more); + dst += more; + } + } + } + *objPtrPtr = objResultPtr; + return TCL_OK; +} + /* *--------------------------------------------------------------------------- * |