Tcl Source Code

2011-04-13  Don Porter  <[email protected]>

	* generic/tclUtil.c:	Rewrite of Tcl_Concat*() routines to 
	prevent segfaults on buffer overflow.  Build them out of existing
	primitives already coded to handle overflow properly.  Uses the
	new TclTrim*() routines. [Bug 3285375]

	* generic/tclCmdMZ.c:	New internal utility routines TclTrimLeft()
	* generic/tclInt.h:	and TclTrimRight().  Refactor the
	* generic/tclUtil.c:	[string trim*] implementations to use them.

2011-04-13  Miguel Sofer  <[email protected]>

	* generic/tclVar.c: fix for [Bug 2662380], crash caused by
	appending to a variable with a write trace that unsets it.

2011-04-13  Donal K. Fellows  <[email protected]>

static int
StringTrimCmd(
    ClientData dummy,		/* Not used. */
    Tcl_Interp *interp,		/* Current interpreter. */
    int objc,			/* Number of arguments. */
    Tcl_Obj *const objv[])	/* Argument objects. */
{


    const char *string1, *string2;
    int triml, trimr, length1, length2;

    if (objc == 3) {
	string2 = TclGetStringFromObj(objv[2], &length2);
    } else if (objc == 2) {
	string2 = DEFAULT_TRIM_SET;
	length2 = strlen(DEFAULT_TRIM_SET);
    } else {
	Tcl_WrongNumArgs(interp, 1, objv, "string ?chars?");
	return TCL_ERROR;
    }
    string1 = TclGetStringFromObj(objv[1], &length1);








    triml = TclTrimLeft(string1, length1, string2, length2);



    trimr = TclTrimRight(string1 + triml, length1 - triml, string2, length2);






































    Tcl_SetObjResult(interp,
	    Tcl_NewStringObj(string1 + triml, length1 - triml - trimr));
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * StringTrimLCmd --

static int
StringTrimLCmd(
    ClientData dummy,		/* Not used. */
    Tcl_Interp *interp,		/* Current interpreter. */
    int objc,			/* Number of arguments. */
    Tcl_Obj *const objv[])	/* Argument objects. */
{


    const char *string1, *string2;
    int trim, length1, length2;

    if (objc == 3) {
	string2 = TclGetStringFromObj(objv[2], &length2);
    } else if (objc == 2) {
	string2 = DEFAULT_TRIM_SET;
	length2 = strlen(DEFAULT_TRIM_SET);
    } else {
	Tcl_WrongNumArgs(interp, 1, objv, "string ?chars?");
	return TCL_ERROR;
    }
    string1 = TclGetStringFromObj(objv[1], &length1);








    trim = TclTrimLeft(string1, length1, string2, length2);


















    Tcl_SetObjResult(interp, Tcl_NewStringObj(string1+trim, length1-trim));
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * StringTrimRCmd --

static int
StringTrimRCmd(
    ClientData dummy,		/* Not used. */
    Tcl_Interp *interp,		/* Current interpreter. */
    int objc,			/* Number of arguments. */
    Tcl_Obj *const objv[])	/* Argument objects. */
{


    const char *string1, *string2;
    int trim, length1, length2;

    if (objc == 3) {
	string2 = TclGetStringFromObj(objv[2], &length2);
    } else if (objc == 2) {
	string2 = DEFAULT_TRIM_SET;
	length2 = strlen(DEFAULT_TRIM_SET);
    } else {
	Tcl_WrongNumArgs(interp, 1, objv, "string ?chars?");
	return TCL_ERROR;
    }
    string1 = TclGetStringFromObj(objv[1], &length1);







    trim = TclTrimRight(string1, length1, string2, length2);


















    Tcl_SetObjResult(interp, Tcl_NewStringObj(string1, length1-trim));
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * TclInitStringCmd --

			    Tcl_Obj *const opts[], int *flagPtr);
MODULE_SCOPE void	TclSubstParse(Tcl_Interp *interp, const char *bytes,
			    int numBytes, int flags, Tcl_Parse *parsePtr,
			    Tcl_InterpState *statePtr);
MODULE_SCOPE int	TclSubstTokens(Tcl_Interp *interp, Tcl_Token *tokenPtr,
			    int count, int *tokensLeftPtr, int line,
			    int *clNextOuter, const char *outerScript);
MODULE_SCOPE int	TclTrimLeft(const char *bytes, int numBytes,
			    const char *trim, int numTrim);
MODULE_SCOPE int	TclTrimRight(const char *bytes, int numBytes,
			    const char *trim, int numTrim);
MODULE_SCOPE Tcl_Obj *	TclpNativeToNormalized(ClientData clientData);
MODULE_SCOPE Tcl_Obj *	TclpFilesystemPathType(Tcl_Obj *pathPtr);
MODULE_SCOPE int	TclpDlopen(Tcl_Interp *interp, Tcl_Obj *pathPtr,
			    Tcl_LoadHandle *loadHandle,
			    Tcl_FSUnloadFileProc **unloadProcPtr);
MODULE_SCOPE int	TclpUtime(Tcl_Obj *pathPtr, struct utimbuf *tval);
#ifdef TCL_LOAD_FROM_MEMORY

    TclUtfToUniChar(buf, &ch);
    return (char) ch;
}

/*
 *----------------------------------------------------------------------
 *
 * TclTrimRight --
 *	Takes two counted strings in the Tcl encoding which must both be
 *	null terminated.  Conceptually trims from the right side of the
 *	first string all characters found in the second string.
 *
 * Results:
 *	The number of bytes to be removed from the end of the string.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclTrimRight(
    const char *bytes,	/* String to be trimmed... */
    int numBytes,	/* ...and its length in bytes */
    const char *trim,	/* String of trim characters... */
    int numTrim)	/* ...and its length in bytes */
{
    const char *p = bytes + numBytes;
    int pInc;

    if ((bytes[numBytes] != '\0') || (trim[numTrim] != '\0')) {
	Tcl_Panic("TclTrimRight works only on null-terminated strings");
    }

    /* Empty strings -> nothing to do */
    if ((numBytes == 0) || (numTrim == 0)) {
	return 0;
    }

    /* Outer loop: iterate over string to be trimmed */
    do {
	Tcl_UniChar ch1;
	const char *q = trim;
	int bytesLeft = numTrim;

	p = Tcl_UtfPrev(p, bytes);
 	pInc = TclUtfToUniChar(p, &ch1);

	/* Inner loop: scan trim string for match to current character */
	do {
	    Tcl_UniChar ch2;
	    int qInc = TclUtfToUniChar(q, &ch2);

	    if (ch1 == ch2) {
		break;
	    }

	    q += qInc;
	    bytesLeft -= qInc;
	} while (bytesLeft);

	if (bytesLeft == 0) {
	    /* No match; trim task done; *p is last non-trimmed char */
	    break;
	}
	pInc = 0;
    } while (p > bytes);

    return numBytes - (p - bytes) - pInc;
}

/*
 *----------------------------------------------------------------------
 *
 * TclTrimLeft --
 *	Takes two counted strings in the Tcl encoding which must both be
 *	null terminated.  Conceptually trims from the left side of the
 *	first string all characters found in the second string.
 *
 * Results:
 *	An integer index into the first string, pointing to the first
 *	character not to be trimmed.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclTrimLeft(
    const char *bytes,	/* String to be trimmed... */
    int numBytes,	/* ...and its length in bytes */
    const char *trim,	/* String of trim characters... */
    int numTrim)	/* ...and its length in bytes */
{
    const char *p = bytes;

    if ((bytes[numBytes] != '\0') || (trim[numTrim] != '\0')) {
	Tcl_Panic("TclTrimLeft works only on null-terminated strings");
    }

    /* Empty strings -> nothing to do */
    if ((numBytes == 0) || (numTrim == 0)) {
	return 0;
    }

    /* Outer loop: iterate over string to be trimmed */
    do {
	Tcl_UniChar ch1;
	int pInc = TclUtfToUniChar(p, &ch1);
	const char *q = trim;
	int bytesLeft = numTrim;

	/* Inner loop: scan trim string for match to current character */
	do {
	    Tcl_UniChar ch2;
	    int qInc = TclUtfToUniChar(q, &ch2);

	    if (ch1 == ch2) {
		break;
	    }

	    q += qInc;
	    bytesLeft -= qInc;
	} while (bytesLeft);

	if (bytesLeft == 0) {
	    /* No match; trim task done; *p is first non-trimmed char */
	    break;
	}

	p += pInc;
	numBytes -= pInc;
    } while (numBytes);

    return p - bytes;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_Concat --
 *
 *	Concatenate a set of strings into a single large string.
 *
 * Results:
 *	The return value is dynamically-allocated string containing a
 *	concatenation of all the strings in argv, with spaces between the

{
    int totalSize, i;
    char *p;
    char *result;

    for (totalSize = 1, i = 0; i < argc; i++) {
	totalSize += strlen(argv[i]) + 1;
	if (totalSize <= 0) {
	    Tcl_Panic("Tcl_Concat: max size of Tcl value exceeded");
	}
    }
    result = ckalloc(totalSize);
    if (argc == 0) {
	*result = '\0';
	return result;
    }
    for (p = result, i = 0; i < argc; i++) {

 */

Tcl_Obj *
Tcl_ConcatObj(
    int objc,			/* Number of objects to concatenate. */
    Tcl_Obj *const objv[])	/* Array of objects to concatenate. */
{
    int i, needSpace = 0;



    Tcl_Obj *objPtr, *resPtr;

    /*
     * Check first to see if all the items are of list type or empty. If so,
     * we will concat them together as lists, and return a list object. This
     * is only valid when the lists are in canonical form.



     */

    for (i = 0;  i < objc;  i++) {
	List *listRepPtr;

	objPtr = objv[i];
	if (objPtr->typePtr != &tclListType) {

    }

    /*
     * Something cannot be determined to be safe, so build the concatenation
     * the slow way, using the string representations.
     */

    TclNewObj(resPtr);
    for (i = 0;  i < objc;  i++) {
	int trim, elemLength;
	const char *element;
	
	objPtr = objv[i];
	element = TclGetStringFromObj(objPtr, &elemLength);







	/* Trim away the leading whitespace */
	trim = TclTrimLeft(element, elemLength, " \f\v\r\t\n", 6);
	element += trim;

	elemLength -= trim;


	/*




	 * Trim away the trailing whitespace.  Do not permit trimming

	 * to expose a final backslash character.




	 */














	trim = TclTrimRight(element, elemLength, " \f\v\r\t\n", 6);







	trim -= trim && (element[elemLength - trim - 1] == '\\');


	elemLength -= trim;

	/* If we're left with empty element after trimming, do nothing */
	if (elemLength == 0) {
	    continue;
	}






	/* Append to the result with space if needed */
	if (needSpace) {




	    Tcl_AppendToObj(resPtr, " ", 1);
	}
	Tcl_AppendToObj(resPtr, element, elemLength);
	needSpace = 1;
    }




    return resPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_StringMatch --
 *