source: trunk/tcl/tclCmdAH.c

/* 
 * tclCmdAH.c --
 *
 *      This file contains the top-level command routines for most of
 *      the Tcl built-in commands whose names begin with the letters
 *      A to H.
 *
 * Copyright (c) 1987-1993 The Regents of the University of California.
 * Copyright (c) 1994-1997 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: tclCmdAH.c,v 1.1 2008-06-04 13:58:04 demin Exp $
 */

#include "tclInt.h"
#include "tclPort.h"

/*
 *----------------------------------------------------------------------
 *
 * Tcl_BreakCmd --
 *
 *      This procedure is invoked to process the "break" Tcl command.
 *      See the user documentation for details on what it does.
 *
 *      With the bytecode compiler, this procedure is only called when
 *      a command name is computed at runtime, and is "break" or the name
 *      to which "break" was renamed: e.g., "set z break; $z"
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_BreakCmd(dummy, interp, argc, argv)
    ClientData dummy;                   /* Not used. */
    Tcl_Interp *interp;                 /* Current interpreter. */
    int argc;                           /* Number of arguments. */
    char **argv;                        /* Argument strings. */
{
    if (argc != 1) {
        Tcl_AppendResult(interp, "wrong # args: should be \"",
                argv[0], "\"", (char *) NULL);
        return TCL_ERROR;
    }
    return TCL_BREAK;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_CaseObjCmd --
 *
 *      This procedure is invoked to process the "case" Tcl command.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_CaseObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    register int i;
    int body, result;
    char *string, *arg;
    int argLen, caseObjc;
    Tcl_Obj *CONST *caseObjv;
    Tcl_Obj *armPtr;

    if (objc < 3) {
        Tcl_WrongNumArgs(interp, 1, objv,
                "string ?in? patList body ... ?default body?");
        return TCL_ERROR;
    }

    /*
     * THIS FAILS IF AN OBJECT'S STRING REP HAS A NULL BYTE.
     */
    
    string = Tcl_GetStringFromObj(objv[1], &argLen);
    body = -1;

    arg = Tcl_GetStringFromObj(objv[2], &argLen);
    if (strcmp(arg, "in") == 0) {
        i = 3;
    } else {
        i = 2;
    }
    caseObjc = objc - i;
    caseObjv = objv + i;

    /*
     * If all of the pattern/command pairs are lumped into a single
     * argument, split them out again.
     * THIS FAILS IF THE ARG'S STRING REP CONTAINS A NULL
     */

    if (caseObjc == 1) {
        Tcl_Obj **newObjv;
        
        Tcl_ListObjGetElements(interp, caseObjv[0], &caseObjc, &newObjv);
        caseObjv = newObjv;
    }

    for (i = 0;  i < caseObjc;  i += 2) {
        int patObjc, j;
        char **patObjv;
        char *pat;
        register char *p;

        if (i == (caseObjc-1)) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "extra case pattern with no body", -1);
            return TCL_ERROR;
        }

        /*
         * Check for special case of single pattern (no list) with
         * no backslash sequences.
         */

        pat = Tcl_GetStringFromObj(caseObjv[i], &argLen);
        for (p = pat;  *p != 0;  p++) { /* FAILS IF NULL BYTE */
            if (isspace(UCHAR(*p)) || (*p == '\\')) {
                break;
            }
        }
        if (*p == 0) {
            if ((*pat == 'd') && (strcmp(pat, "default") == 0)) {
                body = i+1;
            }
            if (Tcl_StringMatch(string, pat)) {
                body = i+1;
                goto match;
            }
            continue;
        }


        /*
         * Break up pattern lists, then check each of the patterns
         * in the list.
         */

        result = Tcl_SplitList(interp, pat, &patObjc, &patObjv);
        if (result != TCL_OK) {
            return result;
        }
        for (j = 0; j < patObjc; j++) {
            if (Tcl_StringMatch(string, patObjv[j])) {
                body = i+1;
                break;
            }
        }
        ckfree((char *) patObjv);
        if (j < patObjc) {
            break;
        }
    }

    match:
    if (body != -1) {
        armPtr = caseObjv[body-1];
        result = Tcl_EvalObj(interp, caseObjv[body]);
        if (result == TCL_ERROR) {
            char msg[100];
            
            arg = Tcl_GetStringFromObj(armPtr, &argLen);
            sprintf(msg, "\n    (\"%.*s\" arm line %d)", argLen, arg,
                    interp->errorLine);
            Tcl_AddObjErrorInfo(interp, msg, -1);
        }
        return result;
    }

    /*
     * Nothing matched: return nothing.
     */

    return TCL_OK;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_CatchObjCmd --
 *
 *      This object-based procedure is invoked to process the "catch" Tcl 
 *      command. See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_CatchObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    Tcl_Obj *varNamePtr = NULL;
    int result;

    if ((objc != 2) && (objc != 3)) {
        Tcl_WrongNumArgs(interp, 1, objv, "command ?varName?");
        return TCL_ERROR;
    }

    /*
     * Save a pointer to the variable name object, if any, in case the
     * Tcl_EvalObj reallocates the bytecode interpreter's evaluation
     * stack rendering objv invalid.
     */
    
    if (objc == 3) {
        varNamePtr = objv[2];
    }
    
    result = Tcl_EvalObj(interp, objv[1]);
    
    if (objc == 3) {
        if (Tcl_ObjSetVar2(interp, varNamePtr, NULL,
                    Tcl_GetObjResult(interp), TCL_PARSE_PART1) == NULL) {
            Tcl_ResetResult(interp);
            Tcl_AppendToObj(Tcl_GetObjResult(interp),  
                    "couldn't save command result in variable", -1);
            return TCL_ERROR;
        }
    }

    /*
     * Set the interpreter's object result to an integer object holding the
     * integer Tcl_EvalObj result. Note that we don't bother generating a
     * string representation. We reset the interpreter's object result
     * to an unshared empty object and then set it to be an integer object.
     */

    Tcl_ResetResult(interp);
    Tcl_SetIntObj(Tcl_GetObjResult(interp), result);
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_ConcatObjCmd --
 *
 *      This object-based procedure is invoked to process the "concat" Tcl
 *      command. See the user documentation for details on what it does/
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ConcatObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    if (objc >= 2) {
        Tcl_SetObjResult(interp, Tcl_ConcatObj(objc-1, objv+1));
    }
    return TCL_OK;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_ContinueCmd -
 *
 *      This procedure is invoked to process the "continue" Tcl command.
 *      See the user documentation for details on what it does.
 *
 *      With the bytecode compiler, this procedure is only called when
 *      a command name is computed at runtime, and is "continue" or the name
 *      to which "continue" was renamed: e.g., "set z continue; $z"
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ContinueCmd(dummy, interp, argc, argv)
    ClientData dummy;                   /* Not used. */
    Tcl_Interp *interp;                 /* Current interpreter. */
    int argc;                           /* Number of arguments. */
    char **argv;                        /* Argument strings. */
{
    if (argc != 1) {
        Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
                "\"", (char *) NULL);
        return TCL_ERROR;
    }
    return TCL_CONTINUE;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_ErrorObjCmd --
 *
 *      This procedure is invoked to process the "error" Tcl command.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ErrorObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    Interp *iPtr = (Interp *) interp;
    register Tcl_Obj *namePtr;
    char *info;
    int infoLen;

    if ((objc < 2) || (objc > 4)) {
        Tcl_WrongNumArgs(interp, 1, objv, "message ?errorInfo? ?errorCode?");
        return TCL_ERROR;
    }
    
    if (objc >= 3) {            /* process the optional info argument */
        info = Tcl_GetStringFromObj(objv[2], &infoLen);
        if (*info != 0) {
            Tcl_AddObjErrorInfo(interp, info, infoLen);
            iPtr->flags |= ERR_ALREADY_LOGGED;
        }
    }
    
    if (objc == 4) {
        namePtr = Tcl_NewStringObj("errorCode", -1);
        Tcl_ObjSetVar2(interp, namePtr, (Tcl_Obj *) NULL, objv[3],
                TCL_GLOBAL_ONLY);
        iPtr->flags |= ERROR_CODE_SET;
        Tcl_DecrRefCount(namePtr); /* we're done with name object */
    }
    
    Tcl_SetObjResult(interp, objv[1]);
    return TCL_ERROR;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_EvalObjCmd --
 *
 *      This object-based procedure is invoked to process the "eval" Tcl 
 *      command. See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_EvalObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    int result;
    register Tcl_Obj *objPtr;

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "arg ?arg ...?");
        return TCL_ERROR;
    }
    
    if (objc == 2) {
        result = Tcl_EvalObj(interp, objv[1]);
    } else {
        /*
         * More than one argument: concatenate them together with spaces
         * between, then evaluate the result.
         */
    
        objPtr = Tcl_ConcatObj(objc-1, objv+1);
        result = Tcl_EvalObj(interp, objPtr);
        Tcl_DecrRefCount(objPtr);  /* we're done with the object */
    }
    if (result == TCL_ERROR) {
        char msg[60];
        sprintf(msg, "\n    (\"eval\" body line %d)", interp->errorLine);
        Tcl_AddObjErrorInfo(interp, msg, -1);
    }
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_ExprObjCmd --
 *
 *      This object-based procedure is invoked to process the "expr" Tcl
 *      command. See the user documentation for details on what it does.
 *
 *      With the bytecode compiler, this procedure is called in two
 *      circumstances: 1) to execute expr commands that are too complicated
 *      or too unsafe to try compiling directly into an inline sequence of
 *      instructions, and 2) to execute commands where the command name is
 *      computed at runtime and is "expr" or the name to which "expr" was
 *      renamed (e.g., "set z expr; $z 2+3")
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ExprObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    register Tcl_Obj *objPtr;
    Tcl_Obj *resultPtr;
    register char *bytes;
    int length, i, result;

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "arg ?arg ...?");
        return TCL_ERROR;
    }

    if (objc == 2) {
        result = Tcl_ExprObj(interp, objv[1], &resultPtr);
        if (result == TCL_OK) {
            Tcl_SetObjResult(interp, resultPtr);
            Tcl_DecrRefCount(resultPtr);  /* done with the result object */
        }
        return result;
    }

    /*
     * Create a new object holding the concatenated argument strings.
     * THIS FAILS IF AN OBJECT'S STRING REP HAS A NULL BYTE.
     */

    bytes = Tcl_GetStringFromObj(objv[1], &length);
    objPtr = Tcl_NewStringObj(bytes, length);
    Tcl_IncrRefCount(objPtr);
    for (i = 2;  i < objc;  i++) {
        Tcl_AppendToObj(objPtr, " ", 1);
        bytes = Tcl_GetStringFromObj(objv[i], &length);
        Tcl_AppendToObj(objPtr, bytes, length);
    }

    /*
     * Evaluate the concatenated string object.
     */

    result = Tcl_ExprObj(interp, objPtr, &resultPtr);
    if (result == TCL_OK) {
        Tcl_SetObjResult(interp, resultPtr);
        Tcl_DecrRefCount(resultPtr);  /* done with the result object */
    }

    /*
     * Free allocated resources.
     */
    
    Tcl_DecrRefCount(objPtr);
    return result;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_ForCmd --
 *
 *      This procedure is invoked to process the "for" Tcl command.
 *      See the user documentation for details on what it does.
 *
 *      With the bytecode compiler, this procedure is only called when
 *      a command name is computed at runtime, and is "for" or the name
 *      to which "for" was renamed: e.g.,
 *      "set z for; $z {set i 0} {$i<100} {incr i} {puts $i}"
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ForCmd(dummy, interp, argc, argv)
    ClientData dummy;                   /* Not used. */
    Tcl_Interp *interp;                 /* Current interpreter. */
    int argc;                           /* Number of arguments. */
    char **argv;                        /* Argument strings. */
{
    int result, value;

    if (argc != 5) {
        Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
                " start test next command\"", (char *) NULL);
        return TCL_ERROR;
    }

    result = Tcl_Eval(interp, argv[1]);
    if (result != TCL_OK) {
        if (result == TCL_ERROR) {
            Tcl_AddErrorInfo(interp, "\n    (\"for\" initial command)");
        }
        return result;
    }
    while (1) {
        result = Tcl_ExprBoolean(interp, argv[2], &value);
        if (result != TCL_OK) {
            return result;
        }
        if (!value) {
            break;
        }
        result = Tcl_Eval(interp, argv[4]);
        if ((result != TCL_OK) && (result != TCL_CONTINUE)) {
            if (result == TCL_ERROR) {
                char msg[60];
                sprintf(msg, "\n    (\"for\" body line %d)",interp->errorLine);
                Tcl_AddErrorInfo(interp, msg);
            }
            break;
        }
        result = Tcl_Eval(interp, argv[3]);
        if (result == TCL_BREAK) {
            break;
        } else if (result != TCL_OK) {
            if (result == TCL_ERROR) {
                Tcl_AddErrorInfo(interp, "\n    (\"for\" loop-end command)");
            }
            return result;
        }
    }
    if (result == TCL_BREAK) {
        result = TCL_OK;
    }
    if (result == TCL_OK) {
        Tcl_ResetResult(interp);
    }
    return result;
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_ForeachObjCmd --
 *
 *      This object-based procedure is invoked to process the "foreach" Tcl
 *      command.  See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl object result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_ForeachObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    int result = TCL_OK;
    int i;                      /* i selects a value list */
    int j, maxj;                /* Number of loop iterations */
    int v;                      /* v selects a loop variable */
    int numLists;               /* Count of value lists */
    Tcl_Obj *bodyPtr;

    /*
     * We copy the argument object pointers into a local array to avoid
     * the problem that "objv" might become invalid. It is a pointer into
     * the evaluation stack and that stack might be grown and reallocated
     * if the loop body requires a large amount of stack space.
     */
    
#define NUM_ARGS 9
    Tcl_Obj *(argObjStorage[NUM_ARGS]);
    Tcl_Obj **argObjv = argObjStorage;
    
#define STATIC_LIST_SIZE 4
    int indexArray[STATIC_LIST_SIZE];     /* Array of value list indices */
    int varcListArray[STATIC_LIST_SIZE];  /* # loop variables per list */
    Tcl_Obj **varvListArray[STATIC_LIST_SIZE]; /* Array of var name lists */
    int argcListArray[STATIC_LIST_SIZE];  /* Array of value list sizes */
    Tcl_Obj **argvListArray[STATIC_LIST_SIZE]; /* Array of value lists */

    int *index = indexArray;
    int *varcList = varcListArray;
    Tcl_Obj ***varvList = varvListArray;
    int *argcList = argcListArray;
    Tcl_Obj ***argvList = argvListArray;

    if (objc < 4 || (objc%2 != 0)) {
        Tcl_WrongNumArgs(interp, 1, objv,
                "varList list ?varList list ...? command");
        return TCL_ERROR;
    }

    /*
     * Create the object argument array "argObjv". Make sure argObjv is
     * large enough to hold the objc arguments.
     */

    if (objc > NUM_ARGS) {
        argObjv = (Tcl_Obj **) ckalloc(objc * sizeof(Tcl_Obj *));
    }
    for (i = 0;  i < objc;  i++) {
        argObjv[i] = objv[i];
    }

    /*
     * Manage numList parallel value lists.
     * argvList[i] is a value list counted by argcList[i]
     * varvList[i] is the list of variables associated with the value list
     * varcList[i] is the number of variables associated with the value list
     * index[i] is the current pointer into the value list argvList[i]
     */

    numLists = (objc-2)/2;
    if (numLists > STATIC_LIST_SIZE) {
        index = (int *) ckalloc(numLists * sizeof(int));
        varcList = (int *) ckalloc(numLists * sizeof(int));
        varvList = (Tcl_Obj ***) ckalloc(numLists * sizeof(Tcl_Obj **));
        argcList = (int *) ckalloc(numLists * sizeof(int));
        argvList = (Tcl_Obj ***) ckalloc(numLists * sizeof(Tcl_Obj **));
    }
    for (i = 0;  i < numLists;  i++) {
        index[i] = 0;
        varcList[i] = 0;
        varvList[i] = (Tcl_Obj **) NULL;
        argcList[i] = 0;
        argvList[i] = (Tcl_Obj **) NULL;
    }

    /*
     * Break up the value lists and variable lists into elements
     * THIS FAILS IF THE OBJECT'S STRING REP HAS A NULL BYTE.
     */

    maxj = 0;
    for (i = 0;  i < numLists;  i++) {
        result = Tcl_ListObjGetElements(interp, argObjv[1+i*2],
                &varcList[i], &varvList[i]);
        if (result != TCL_OK) {
            goto done;
        }
        if (varcList[i] < 1) {
            Tcl_AppendToObj(Tcl_GetObjResult(interp),
                    "foreach varlist is empty", -1);
            result = TCL_ERROR;
            goto done;
        }
        
        result = Tcl_ListObjGetElements(interp, argObjv[2+i*2],
                &argcList[i], &argvList[i]);
        if (result != TCL_OK) {
            goto done;
        }
        
        j = argcList[i] / varcList[i];
        if ((argcList[i] % varcList[i]) != 0) {
            j++;
        }
        if (j > maxj) {
            maxj = j;
        }
    }

    /*
     * Iterate maxj times through the lists in parallel
     * If some value lists run out of values, set loop vars to ""
     */
    
    bodyPtr = argObjv[objc-1];
    for (j = 0;  j < maxj;  j++) {
        for (i = 0;  i < numLists;  i++) {
            /*
             * If a variable or value list object has been converted to
             * another kind of Tcl object, convert it back to a list object
             * and refetch the pointer to its element array.
             */

            if (argObjv[1+i*2]->typePtr != &tclListType) {
                result = Tcl_ListObjGetElements(interp, argObjv[1+i*2],
                        &varcList[i], &varvList[i]);
                if (result != TCL_OK) {
                    panic("Tcl_ForeachObjCmd: could not reconvert variable list %d to a list object\n", i);
                }
            }
            if (argObjv[2+i*2]->typePtr != &tclListType) {
                result = Tcl_ListObjGetElements(interp, argObjv[2+i*2],
                        &argcList[i], &argvList[i]);
                if (result != TCL_OK) {
                    panic("Tcl_ForeachObjCmd: could not reconvert value list %d to a list object\n", i);
                }
            }
            
            for (v = 0;  v < varcList[i];  v++) {
                int k = index[i]++;
                Tcl_Obj *valuePtr, *varValuePtr;
                int isEmptyObj = 0;
                
                if (k < argcList[i]) {
                    valuePtr = argvList[i][k];
                } else {
                    valuePtr = Tcl_NewObj(); /* empty string */
                    isEmptyObj = 1;
                }
                varValuePtr = Tcl_ObjSetVar2(interp, varvList[i][v], NULL,
                        valuePtr, TCL_PARSE_PART1);
                if (varValuePtr == NULL) {
                    if (isEmptyObj) {
                        Tcl_DecrRefCount(valuePtr);
                    }
                    Tcl_ResetResult(interp);
                    Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                        "couldn't set loop variable: \"",
                        Tcl_GetStringFromObj(varvList[i][v], (int *) NULL),
                        "\"", (char *) NULL);
                    result = TCL_ERROR;
                    goto done;
                }

            }
        }

        result = Tcl_EvalObj(interp, bodyPtr);
        if (result != TCL_OK) {
            if (result == TCL_CONTINUE) {
                result = TCL_OK;
            } else if (result == TCL_BREAK) {
                result = TCL_OK;
                break;
            } else if (result == TCL_ERROR) {
                char msg[100];
                sprintf(msg, "\n    (\"foreach\" body line %d)",
                        interp->errorLine);
                Tcl_AddObjErrorInfo(interp, msg, -1);
                break;
            } else {
                break;
            }
        }
    }
    if (result == TCL_OK) {
        Tcl_ResetResult(interp);
    }

    done:
    if (numLists > STATIC_LIST_SIZE) {
        ckfree((char *) index);
        ckfree((char *) varcList);
        ckfree((char *) argcList);
        ckfree((char *) varvList);
        ckfree((char *) argvList);
    }
    if (argObjv != argObjStorage) {
        ckfree((char *) argObjv);
    }
    return result;
#undef STATIC_LIST_SIZE
#undef NUM_ARGS
}


/*
 *----------------------------------------------------------------------
 *
 * Tcl_FormatObjCmd --
 *
 *      This procedure is invoked to process the "format" Tcl command.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

        /* ARGSUSED */
int
Tcl_FormatObjCmd(dummy, interp, objc, objv)
    ClientData dummy;           /* Not used. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    register char *format;      /* Used to read characters from the format
                                 * string. */
    int formatLen;              /* The length of the format string */
    char *endPtr;               /* Points to the last char in format array */
    char newFormat[40];         /* A new format specifier is generated here. */
    int width;                  /* Field width from field specifier, or 0 if
                                 * no width given. */
    int precision;              /* Field precision from field specifier, or 0
                                 * if no precision given. */
    int size;                   /* Number of bytes needed for result of
                                 * conversion, based on type of conversion
                                 * ("e", "s", etc.), width, and precision. */
    int intValue;               /* Used to hold value to pass to sprintf, if
                                 * it's a one-word integer or char value */
    char *ptrValue = NULL;      /* Used to hold value to pass to sprintf, if
                                 * it's a one-word value. */
    double doubleValue;         /* Used to hold value to pass to sprintf if
                                 * it's a double value. */
    int whichValue;             /* Indicates which of intValue, ptrValue,
                                 * or doubleValue has the value to pass to
                                 * sprintf, according to the following
                                 * definitions: */
#   define INT_VALUE 0
#   define PTR_VALUE 1
#   define DOUBLE_VALUE 2
#   define MAX_FLOAT_SIZE 320
    
    Tcl_Obj *resultPtr;         /* Where result is stored finally. */
    char staticBuf[MAX_FLOAT_SIZE + 1];
                                /* A static buffer to copy the format results 
                                 * into */
    char *dst = staticBuf;      /* The buffer that sprintf writes into each
                                 * time the format processes a specifier */
    int dstSize = MAX_FLOAT_SIZE;
                                /* The size of the dst buffer */
    int noPercent;              /* Special case for speed:  indicates there's
                                 * no field specifier, just a string to copy.*/
    int objIndex;               /* Index of argument to substitute next. */
    int gotXpg = 0;             /* Non-zero means that an XPG3 %n$-style
                                 * specifier has been seen. */
    int gotSequential = 0;      /* Non-zero means that a regular sequential
                                 * (non-XPG3) conversion specifier has been
                                 * seen. */
    int useShort;               /* Value to be printed is short (half word). */
    char *end;                  /* Used to locate end of numerical fields. */

    /*
     * This procedure is a bit nasty.  The goal is to use sprintf to
     * do most of the dirty work.  There are several problems:
     * 1. this procedure can't trust its arguments.
     * 2. we must be able to provide a large enough result area to hold
     *    whatever's generated.  This is hard to estimate.
     * 2. there's no way to move the arguments from objv to the call
     *    to sprintf in a reasonable way.  This is particularly nasty
     *    because some of the arguments may be two-word values (doubles).
     * So, what happens here is to scan the format string one % group
     * at a time, making many individual calls to sprintf.
     */

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv,
                "formatString ?arg arg ...?");
        return TCL_ERROR;
    }

    format = Tcl_GetStringFromObj(objv[1], &formatLen);
    endPtr = format + formatLen;
    resultPtr = Tcl_NewObj();
    objIndex = 2;

    while (format < endPtr) {
        register char *newPtr = newFormat;

        width = precision = noPercent = useShort = 0;
        whichValue = PTR_VALUE;

        /*
         * Get rid of any characters before the next field specifier.
         */
        if (*format != '%') {
            ptrValue = format;
            while ((*format != '%') && (format < endPtr)) {
                format++;
            }
            size = format - ptrValue;
            noPercent = 1;
            goto doField;
        }

        if (format[1] == '%') {
            ptrValue = format;
            size = 1;
            noPercent = 1;
            format += 2;
            goto doField;
        }

        /*
         * Parse off a field specifier, compute how many characters
         * will be needed to store the result, and substitute for
         * "*" size specifiers.
         */
        *newPtr = '%';
        newPtr++;
        format++;
        if (isdigit(UCHAR(*format))) {
            int tmp;

            /*
             * Check for an XPG3-style %n$ specification.  Note: there
             * must not be a mixture of XPG3 specs and non-XPG3 specs
             * in the same format string.
             */

            tmp = strtoul(format, &end, 10);
            if (*end != '$') {
                goto notXpg;
            }
            format = end+1;
            gotXpg = 1;
            if (gotSequential) {
                goto mixedXPG;
            }
            objIndex = tmp+1;
            if ((objIndex < 2) || (objIndex >= objc)) {
                goto badIndex;
            }
            goto xpgCheckDone;
        }

        notXpg:
        gotSequential = 1;
        if (gotXpg) {
            goto mixedXPG;
        }

        xpgCheckDone:
        while ((*format == '-') || (*format == '#') || (*format == '0')
                || (*format == ' ') || (*format == '+')) {
            *newPtr = *format;
            newPtr++;
            format++;
        }
        if (isdigit(UCHAR(*format))) {
            width = strtoul(format, &end, 10);
            format = end;
        } else if (*format == '*') {
            if (objIndex >= objc) {
                goto badIndex;
            }
            if (Tcl_GetIntFromObj(interp, objv[objIndex], 
                    &width) != TCL_OK) {
                goto fmtError;
            }
            objIndex++;
            format++;
        }
        if (width > 100000) {
            /*
             * Don't allow arbitrarily large widths:  could cause core
             * dump when we try to allocate a zillion bytes of memory
             * below.
             */

            width = 100000;
        } else if (width < 0) {
            width = 0;
        }
        if (width != 0) {
            TclFormatInt(newPtr, width);
            while (*newPtr != 0) {
                newPtr++;
            }
        }
        if (*format == '.') {
            *newPtr = '.';
            newPtr++;
            format++;
        }
        if (isdigit(UCHAR(*format))) {
            precision = strtoul(format, &end, 10);
            format = end;
        } else if (*format == '*') {
            if (objIndex >= objc) {
                goto badIndex;
            }
            if (Tcl_GetIntFromObj(interp, objv[objIndex], 
                    &precision) != TCL_OK) {
                goto fmtError;
            }
            objIndex++;
            format++;
        }
        if (precision != 0) {
            TclFormatInt(newPtr, precision);
            while (*newPtr != 0) {
                newPtr++;
            }
        }
        if (*format == 'l') {
            format++;
        } else if (*format == 'h') {
            useShort = 1;
            *newPtr = 'h';
            newPtr++;
            format++;
        }
        *newPtr = *format;
        newPtr++;
        *newPtr = 0;
        if (objIndex >= objc) {
            goto badIndex;
        }
        switch (*format) {
            case 'i':
                newPtr[-1] = 'd';
            case 'd':
            case 'o':
            case 'u':
            case 'x':
            case 'X':
                if (Tcl_GetIntFromObj(interp, objv[objIndex], 
                        (int *) &intValue) != TCL_OK) {
                    goto fmtError;
                }
                whichValue = INT_VALUE;
                size = 40 + precision;
                break;
            case 's':
                ptrValue = Tcl_GetStringFromObj(objv[objIndex], &size);
                break;
            case 'c':
                if (Tcl_GetIntFromObj(interp, objv[objIndex], 
                        (int *) &intValue) != TCL_OK) {
                    goto fmtError;
                }
                whichValue = INT_VALUE;
                size = 1;
                break;
            case 'e':
            case 'E':
            case 'f':
            case 'g':
            case 'G':
                if (Tcl_GetDoubleFromObj(interp, objv[objIndex], 
                        &doubleValue) != TCL_OK) {
                    goto fmtError;
                }
                whichValue = DOUBLE_VALUE;
                size = MAX_FLOAT_SIZE;
                if (precision > 10) {
                    size += precision;
                }
                break;
            case 0:
                Tcl_SetResult(interp,
                        "format string ended in middle of field specifier",
                        TCL_STATIC);
                goto fmtError;
            default:
                {
                    char buf[40];
                    sprintf(buf, "bad field specifier \"%c\"", *format);
                    Tcl_SetResult(interp, buf, TCL_VOLATILE);
                    goto fmtError;
                }
        }
        objIndex++;
        format++;

        /*
         * Make sure that there's enough space to hold the formatted
         * result, then format it.
         */

        doField:
        if (width > size) {
            size = width;
        }
        if (noPercent) {
            Tcl_AppendToObj(resultPtr, ptrValue, size);
        } else {
            if (size > dstSize) {
                if (dst != staticBuf) {
                    ckfree(dst);
                }
                dst = (char *) ckalloc((unsigned) (size + 1));
                dstSize = size;
            }

            if (whichValue == DOUBLE_VALUE) {
                sprintf(dst, newFormat, doubleValue);
            } else if (whichValue == INT_VALUE) {
                if (useShort) {
                    sprintf(dst, newFormat, (short) intValue);
                } else {
                    sprintf(dst, newFormat, intValue);
                }
            } else {
                sprintf(dst, newFormat, ptrValue);
            }
            Tcl_AppendToObj(resultPtr, dst, -1);
        }
    }

    Tcl_SetObjResult(interp, resultPtr);
    if(dst != staticBuf) {
        ckfree(dst);
    }
    return TCL_OK;

    mixedXPG:
    Tcl_SetResult(interp, 
            "cannot mix \"%\" and \"%n$\" conversion specifiers", TCL_STATIC);
    goto fmtError;

    badIndex:
    if (gotXpg) {
        Tcl_SetResult(interp, 
                "\"%n$\" argument index out of range", TCL_STATIC);
    } else {
        Tcl_SetResult(interp, 
                "not enough arguments for all format specifiers", TCL_STATIC);
    }

    fmtError:
    if(dst != staticBuf) {
        ckfree(dst);
    }
    Tcl_DecrRefCount(resultPtr);
    return TCL_ERROR;
}