Tcl Source Code

2011-05-03  Don Porter  <[email protected]>


	* generic/tclDictObj.c:	Tighten SetDictFromAny().

2011-05-02  Don Porter  <[email protected]>

	* generic/tclCmdMZ.c:	Revised TclFindElement() interface.  The
	* generic/tclDictObj.c:	final argument had been bracePtr, the address
	* generic/tclListObj.c:	of a boolean var, where the caller can be told

 */

static int
SetListFromAny(
    Tcl_Interp *interp,		/* Used for error reporting if not NULL. */
    Tcl_Obj *objPtr)		/* The object to convert. */
{
    char *string, *s;
    const char *elemStart, *nextElem;
    int lenRemain, length, estCount, elemSize, i, j, result;
    const char *limit;		/* Points just after string's last byte. */
    register const char *p;
    register Tcl_Obj **elemPtrs;
    register Tcl_Obj *elemPtr;
    List *listRepPtr;


    /*
     * Dictionaries are a special case; they have a string representation such
     * that *all* valid dictionaries are valid lists. Hence we can convert
     * more directly. Only do this when there's no existing string rep; if
     * there is, it is the string rep that's authoritative (because it could
     * describe duplicate keys).

	/*
	 * Populate the list representation.
	 */

	elemPtrs = &listRepPtr->elements;
	Tcl_DictObjFirst(NULL, objPtr, &search, &keyPtr, &valuePtr, &done);
	i = 0;
	while (!done) {
	    elemPtrs[i++] = keyPtr;
	    elemPtrs[i++] = valuePtr;
	    Tcl_IncrRefCount(keyPtr);
	    Tcl_IncrRefCount(valuePtr);
	    Tcl_DictObjNext(&search, &keyPtr, &valuePtr, &done);
	}

	/*
	 * Swap the representations.
	 */

	goto commitRepresentation;
    }

    /*
     * Get the string representation. Make it up-to-date if necessary.
     */

    string = TclGetStringFromObj(objPtr, &length);

    /*
     * Parse the string into separate string objects, and create a List
     * structure that points to the element string objects. 
     *
     * First, allocate enough space to hold a (Tcl_Obj *) for each
     * (possible) list element.
     */

    estCount = TclMaxListLength(string, length, &limit);
    estCount += (estCount == 0); /* Smallest List struct holds 1 element. */
    listRepPtr = AttemptNewList(interp, estCount, NULL);
    if (listRepPtr == NULL) {
	return TCL_ERROR;
    }
    elemPtrs = &listRepPtr->elements;

    /* Each iteration, parse and store a list element */
    for (p=string, lenRemain=length, i=0;
	    lenRemain > 0;
	    p=nextElem, lenRemain=limit-nextElem, i++) {

	int literal;

	result = TclFindElement(interp, p, lenRemain, &elemStart, &nextElem,
		&elemSize, &literal);
	if (result != TCL_OK) {
	    for (j = 0;  j < i;  j++) {
		elemPtr = elemPtrs[j];
		Tcl_DecrRefCount(elemPtr);
	    }
	    ckfree((char *) listRepPtr);
	    return result;
	}
	if (elemStart >= limit) {
	    break;
	}
	if (i > estCount) {
	    Tcl_Panic("SetListFromAny: bad size estimate for list");
	}

	/*
	 * Allocate a Tcl object for the element and initialize it from the
	 * "elemSize" bytes starting at "elemStart".
	 */

	s = ckalloc((unsigned) elemSize + 1);
	if (literal) {
	    memcpy(s, elemStart, (size_t) elemSize);
	    s[elemSize] = 0;
	} else {


	    elemSize = TclCopyAndCollapse(elemSize, elemStart, s);

	}

	TclNewObj(elemPtr);
	elemPtr->bytes = s;
	elemPtr->length = elemSize;
	elemPtrs[i] = elemPtr;
	Tcl_IncrRefCount(elemPtr);	/* Since list now holds ref to it. */
    }

    listRepPtr->elemCount = i;


    /*
     * Free the old internalRep before setting the new one. We do this as late
     * as possible to allow the conversion code, in particular
     * Tcl_GetStringFromObj, to use that old internalRep.
     */

  commitRepresentation:
    TclFreeIntRep(objPtr);
    ListSetIntRep(objPtr, listRepPtr);
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------