/*
 * tclProc.c --
 *
 *	This file contains routines that implement Tcl procedures, including
 *	the "proc" and "uplevel" commands.
 *
 * Copyright (c) 1987-1993 The Regents of the University of California.
 * Copyright (c) 1994-1998 Sun Microsystems, Inc.
 * Copyright (c) 2004-2006 Miguel Sofer
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclProc.c,v 1.46.2.29 2007/06/15 20:27:47 dgp Exp $
 */

#include "tclInt.h"
#include "tclCompile.h"

/*
 * Prototypes for static functions in this file
 */

static void		DupLambdaInternalRep(Tcl_Obj *objPtr,
			    Tcl_Obj *copyPtr);
static void		FreeLambdaInternalRep(Tcl_Obj *objPtr);
static int              InitArgsAndLocals(Tcl_Interp *interp,
	                    Tcl_Obj *procNameObj, int skip);
static void		InitCompiledLocals(Tcl_Interp *interp,
			    ByteCode *codePtr, CompiledLocal *localPtr,
			    Var *varPtr, Namespace *nsPtr);
static int	        PushProcCallFrame(ClientData clientData,
			    register Tcl_Interp *interp, int objc,
			    Tcl_Obj *CONST objv[], int isLambda);

static void		ProcBodyDup(Tcl_Obj *srcPtr, Tcl_Obj *dupPtr);
static void		ProcBodyFree(Tcl_Obj *objPtr);
static void		MakeProcError(Tcl_Interp *interp,
			    Tcl_Obj *procNameObj);
static void		MakeLambdaError(Tcl_Interp *interp,
			    Tcl_Obj *procNameObj);
static int		SetLambdaFromAny(Tcl_Interp *interp, Tcl_Obj *objPtr);

    }
    return (Proc *) 0;
}

/*
 *----------------------------------------------------------------------
 *
 * InitArgsAndLocals --
 *
 *	This routine is invoked in order to initialize the arguments and other
 *	compiled locals	table for a new call frame. 
 *
 * Results:
 *	A standard Tcl result.
 *
 * Side effects:
 *      Allocates memory on the stack for the compiled local variables, the
 *      caller is responsible for freeing them. Initialises all variables.
 *	May invoke various name resolvers in order to determine which
 *	variables are being referenced at runtime. 
 *
 *----------------------------------------------------------------------
 */

static int
InitArgsAndLocals(
    register Tcl_Interp *interp,/* Interpreter in which procedure was
				 * invoked. */
    Tcl_Obj *procNameObj,	/* Procedure name for error reporting. */
    int skip)			/* Number of initial arguments to be skipped,
				 * i.e., words in the "command name". */
{
    CallFrame *framePtr = ((Interp *)interp)->varFramePtr;
    register Proc *procPtr = framePtr->procPtr;
    ByteCode *codePtr = procPtr->bodyPtr->internalRep.otherValuePtr;
    register Var *varPtr;
    register CompiledLocal *localPtr;
    int localCt, numArgs, argCt, i, imax;
    Var *compiledLocals;
    Tcl_Obj *const *argObjs;
    Tcl_Obj **desiredObjs;
    const char *final;
    
    /*
     * Create the "compiledLocals" array. Make sure it is large enough to hold
     * all the procedure's compiled local variables, including its formal
     * parameters.
     */

    localCt = procPtr->numCompiledLocals;
    compiledLocals = (Var*) TclStackAlloc(interp, (int)(localCt*sizeof(Var)));
    framePtr->numCompiledLocals = localCt;
    framePtr->compiledLocals = compiledLocals;

    /*
     * Match and assign the call's actual parameters to the procedure's formal
     * arguments. The formal arguments are described by the first numArgs
     * entries in both the Proc structure's local variable list and the call
     * frame's local variable array.
     */

    numArgs = procPtr->numArgs;
    argCt = framePtr->objc - skip;	/* Set it to the number of args to the
					 * procedure. */
    argObjs = framePtr->objv + skip;
    varPtr = framePtr->compiledLocals;
    localPtr = procPtr->firstLocalPtr;
    if (numArgs == 0) {
	if (argCt) {
	    goto incorrectArgs;
	} else {
	    goto correctArgs;
	}
    }
    imax = ((argCt < numArgs - 1)? argCt : (numArgs - 1));
    for (i = 0; i < imax; i++) {
	/*
	 * "Normal" arguments; last formal is special, depends on it being
	 * 'args'.
	 */

	Tcl_Obj *objPtr = argObjs[i];

	varPtr->value.objPtr = objPtr;
	Tcl_IncrRefCount(objPtr);	/* Local var is a reference. */
	varPtr->name = localPtr->name;
	varPtr->nsPtr = NULL;
	varPtr->hPtr = NULL;
	varPtr->refCount = 0;
	varPtr->tracePtr = NULL;
	varPtr->searchPtr = NULL;
	varPtr->flags = localPtr->flags;
	varPtr++;
	localPtr = localPtr->nextPtr;
    }
    for (; i < (numArgs - 1); i++) {
	/*
	 * This loop is entered if argCt < (numArgs-1). Set default values;
	 * last formal is special.
	 */

	if (localPtr->defValuePtr != NULL) {
	    Tcl_Obj *objPtr = localPtr->defValuePtr;

	    varPtr->value.objPtr = objPtr;
	    Tcl_IncrRefCount(objPtr);	/* Local var is a reference. */
	    varPtr->name = localPtr->name;
	    varPtr->nsPtr = NULL;
	    varPtr->hPtr = NULL;
	    varPtr->refCount = 0;
	    varPtr->tracePtr = NULL;
	    varPtr->searchPtr = NULL;
	    varPtr->flags = localPtr->flags;
	    varPtr++;
	    localPtr = localPtr->nextPtr;
	} else {
	    goto incorrectArgs;
	}
    }

    /*
     * When we get here, the last formal argument remains to be defined:
     * localPtr and varPtr point to the last argument to be initialized.
     */

    if (localPtr->flags & VAR_IS_ARGS) {
	Tcl_Obj *listPtr = Tcl_NewListObj(argCt-i, argObjs+i);

	varPtr->value.objPtr = listPtr;
	Tcl_IncrRefCount(listPtr);	/* Local var is a reference. */
    } else if (argCt == numArgs) {
	Tcl_Obj *objPtr = argObjs[i];

	varPtr->value.objPtr = objPtr;
	Tcl_IncrRefCount(objPtr);	/* Local var is a reference. */
    } else if ((argCt < numArgs) && (localPtr->defValuePtr != NULL)) {
	Tcl_Obj *objPtr = localPtr->defValuePtr;

	varPtr->value.objPtr = objPtr;
	Tcl_IncrRefCount(objPtr);	/* Local var is a reference. */
    } else {

	goto incorrectArgs;
    }

    varPtr->name = localPtr->name;
    varPtr->nsPtr = NULL;
    varPtr->hPtr = NULL;
    varPtr->refCount = 0;
    varPtr->tracePtr = NULL;
    varPtr->searchPtr = NULL;
    varPtr->flags = localPtr->flags;

    localPtr = localPtr->nextPtr;
    varPtr++;

    /*
     * Initialise and resolve the remaining compiledLocals.
     */

  correctArgs:
    if (localPtr) {
	InitCompiledLocals(interp, codePtr, localPtr, varPtr, framePtr->nsPtr);
    }

    return TCL_OK;


    incorrectArgs:
    /*
     * Do initialise all compiled locals, to avoid problems at
     * DeleteLocalVars.
     */

    final = NULL;
    InitCompiledLocals(interp, codePtr, localPtr, varPtr, framePtr->nsPtr);
    
    /*
     * Build up desired argument list for Tcl_WrongNumArgs
     */
    
    desiredObjs = (Tcl_Obj **) TclStackAlloc(interp,
	    (int) sizeof(Tcl_Obj *) * (numArgs+1));
    
#ifdef AVOID_HACKS_FOR_ITCL
    desiredObjs[0] = framePtr->objv[skip-1];
#else
    desiredObjs[0] = ((framePtr->isProcCallFrame & FRAME_IS_LAMBDA)
	    ? framePtr->objv[skip-1]
	    : Tcl_NewListObj(skip, framePtr->objv));
#endif /* AVOID_HACKS_FOR_ITCL */
    Tcl_IncrRefCount(desiredObjs[0]);
    
    localPtr = procPtr->firstLocalPtr;
    for (i=1 ; i<=numArgs ; i++) {
	Tcl_Obj *argObj;
	
	if (localPtr->defValuePtr != NULL) {
	    TclNewObj(argObj);
	    Tcl_AppendStringsToObj(argObj, "?", localPtr->name, "?", NULL);
	} else if ((i==numArgs) && !strcmp(localPtr->name, "args")) {
	    numArgs--;
	    final = "...";
	    break;
	} else {
	    argObj = Tcl_NewStringObj(localPtr->name, -1);
	}
	desiredObjs[i] = argObj;
	localPtr = localPtr->nextPtr;
    }
    
    Tcl_ResetResult(interp);
    Tcl_WrongNumArgs(interp, numArgs+1, desiredObjs, final);
    
    for (i=0 ; i<=numArgs ; i++) {
	Tcl_DecrRefCount(desiredObjs[i]);
    }
    TclStackFree(interp);
    return TCL_ERROR;
}

/*
 *----------------------------------------------------------------------
 *
 * InitCompiledLocals --
 *
 *	This routine is invoked in order to initialize the compiled locals
 *	table for a new call frame.
 *
 * Results:
 *	None.

    InitCompiledLocals(interp, codePtr, localPtr, varPtr, nsPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * PushProcCallFrame --
 *
 *	Compiles a proc body if necessary, then pushes a CallFrame suitable
 *	for executing it.
 *
 * Results:
 *	A standard Tcl object result value.
 *
 * Side effects:
 *	The proc's body may be recompiled. A CallFrame is pushed, it will have
 *      to be popped by the caller.
 *
 *----------------------------------------------------------------------
 */

static int
PushProcCallFrame(
    ClientData clientData, 	/* Record describing procedure to be
				 * interpreted. */
    register Tcl_Interp *interp,/* Interpreter in which procedure was
				 * invoked. */
    int objc,			/* Count of number of arguments to this
				 * procedure. */
    Tcl_Obj *CONST objv[],	/* Argument value objects. */
    int isLambda)		/* 1 if this is a call by ApplyObjCmd: it
				 * needs special rules for error msg */
{
    Proc *procPtr = (Proc *) clientData;
    Namespace *nsPtr = procPtr->cmdPtr->nsPtr;
    CallFrame *framePtr, **framePtrPtr;
    int result;

    /*
     * If necessary (i.e. if we haven't got a suitable compilation already
     * cached) compile the procedure's body. The compiler will allocate frame
     * slots for the procedure's non-argument local variables. Note that
     * compiling the body might increase procPtr->numCompiledLocals if new
     * local variables are found while compiling.
     */

    if (procPtr->bodyPtr->typePtr == &tclByteCodeType) {
	Interp *iPtr = (Interp *) interp;
	ByteCode *codePtr = procPtr->bodyPtr->internalRep.otherValuePtr;

	/*
	 * When we've got bytecode, this is the check for validity. That is,
	 * the bytecode must be for the right interpreter (no cross-leaks!),
	 * the code must be from the current epoch (so subcommand compilation
	 * is up-to-date), the namespace must match (so variable handling
	 * is right) and the resolverEpoch must match (so that new shadowed
	 * commands and/or resolver changes are considered).
	 */

 	if (((Interp *) *codePtr->interpHandle != iPtr)
		|| (codePtr->compileEpoch != iPtr->compileEpoch)
		|| (codePtr->nsPtr != nsPtr)
		|| (codePtr->nsEpoch != nsPtr->resolverEpoch)) {
	    goto doCompilation;
	}
    } else {
    doCompilation:
	result = ProcCompileProc(interp, procPtr, procPtr->bodyPtr, nsPtr,
		(isLambda ? "body of lambda term" : "body of proc"),
		TclGetString(objv[isLambda]), &procPtr);
	if (result != TCL_OK) {
	    return result;
	}
    }

    /*
     * Set up and push a new call frame for the new procedure invocation.
     * This call frame will execute in the proc's namespace, which might be
     * different than the current namespace. The proc's namespace is that of
     * its command, which can change if the command is renamed from one
     * namespace to another.
     */

    framePtrPtr = &framePtr;
    result = TclPushStackFrame(interp, (Tcl_CallFrame **) framePtrPtr,
	    (Tcl_Namespace *) nsPtr,
	    (isLambda? (FRAME_IS_PROC|FRAME_IS_LAMBDA) : FRAME_IS_PROC));
    if (result != TCL_OK) {
	return result;
    }

    framePtr->objc = objc;
    framePtr->objv = objv;
    framePtr->procPtr = procPtr;

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * TclObjInterpProc --
 *
 *	When a Tcl procedure gets invoked during bytecode evaluation, this
 *	object-based routine gets invoked to interpret the procedure.
 *
 * Results:
 *	A standard Tcl object result value.
 *

				 * interpreted. */
    register Tcl_Interp *interp,/* Interpreter in which procedure was
				 * invoked. */
    int objc,			/* Count of number of arguments to this
				 * procedure. */
    Tcl_Obj *CONST objv[])	/* Argument value objects. */
{





















    int result;
    







    result = PushProcCallFrame(clientData, interp, objc, objv, /*isLambda*/ 0);



    if (result == TCL_OK) {







	return TclObjInterpProcCore(interp, objv[0], 1, &MakeProcError);





    } else {





	return TCL_ERROR;
    }























}

/*
 *----------------------------------------------------------------------
 *
 * TclObjInterpProcCore --
 *

 *----------------------------------------------------------------------
 */

int
TclObjInterpProcCore(
    register Tcl_Interp *interp,/* Interpreter in which procedure was
				 * invoked. */


    Tcl_Obj *procNameObj,	/* Procedure name for error reporting. */


    int skip,			/* Number of initial arguments to be skipped,
				 * i.e., words in the "command name". */
    ProcErrorProc errorProc)	/* How to convert results from the script into
				 * results of the overall procedure. */
{
    CallFrame *framePtr = ((Interp *)interp)->varFramePtr;
    register Proc *procPtr = framePtr->procPtr;



















































































































    ByteCode *codePtr = procPtr->bodyPtr->internalRep.otherValuePtr;

    int result;






    result = InitArgsAndLocals(interp, procNameObj, skip);






    if (result != TCL_OK) {
































	goto procDone;






















    }

#if defined(TCL_COMPILE_DEBUG)
    if (tclTraceExec >= 1) {
	if (framePtr->isProcCallFrame & FRAME_IS_LAMBDA) {
	    fprintf(stdout, "Calling lambda ");
	} else {
	    fprintf(stdout, "Calling proc ");
	}
	for (i = 0; i < framePtr->objc; i++) {
	    TclPrintObject(stdout, framePtr->objv[i], 15);
	    fprintf(stdout, " ");
	}
	fprintf(stdout, "\n");
	fflush(stdout);
    }
#endif /*TCL_COMPILE_DEBUG*/

    /*
     * Invoke the commands in the procedure's body.
     */

    procPtr->refCount++;
    ((Interp *)interp)->numLevels++;


    if (TclInterpReady(interp) == TCL_ERROR) {
	result = TCL_ERROR;

    } else {
	codePtr->refCount++;
	result = TclExecuteByteCode(interp, codePtr);
	codePtr->refCount--;
	if (codePtr->refCount <= 0) {
	    TclCleanupByteCode(codePtr);
	}
    }

    ((Interp *)interp)->numLevels--;
    procPtr->refCount--;
    if (procPtr->refCount <= 0) {
	TclProcCleanupProc(procPtr);
    }

    /*
     * If the procedure is completing normally, we can skip directly to the

    Namespace *nsPtr,		/* Namespace containing procedure. */
    CONST char *description,	/* string describing this body of code. */
    CONST char *procName,	/* Name of this procedure. */
    Proc **procPtrPtr)		/* Points to storage where a replacement
				 * (Proc *) value may be written. */
{
    Interp *iPtr = (Interp *) interp;
    int i;
    Tcl_CallFrame *framePtr;
    Proc *saveProcPtr;
    ByteCode *codePtr = bodyPtr->internalRep.otherValuePtr;
    CompiledLocal *localPtr;

    /*
     * If necessary, compile the procedure's body. The compiler will allocate

     * Precompiled procedure bodies, however, are immutable and therefore they
     * are not recompiled, even if things have changed.
     */

    if (bodyPtr->typePtr == &tclByteCodeType) {
 	if (((Interp *) *codePtr->interpHandle == iPtr)
		&& (codePtr->compileEpoch == iPtr->compileEpoch)
		&& (codePtr->nsPtr == nsPtr)
		&& (codePtr->nsEpoch == nsPtr->resolverEpoch)) {
	    return TCL_OK;
	} else {
	    if (codePtr->flags & TCL_BYTECODE_PRECOMPILED) {
		if ((Interp *) *codePtr->interpHandle != iPtr) {
		    Tcl_AppendResult(interp,
			    "a precompiled script jumped interps", NULL);
		    return TCL_ERROR;
		}
		codePtr->compileEpoch = iPtr->compileEpoch;
		codePtr->nsPtr = nsPtr;
	    } else {
		bodyPtr->typePtr->freeIntRepProc(bodyPtr);
		bodyPtr->typePtr = NULL;
	    }
 	}
    }
    if (bodyPtr->typePtr != &tclByteCodeType) {
	Tcl_HashEntry *hePtr;

#ifdef TCL_COMPILE_DEBUG
 	if (tclTraceCompile >= 1) {
 	    /*
 	     * Display a line summarizing the top level command we are about
 	     * to compile.
 	     */

	    Tcl_SetCommandInfoFromToken(token, &info);

	    procPtr->refCount--;
	    *procPtrPtr = procPtr = newProc;
	}
 	iPtr->compiledProcPtr = procPtr;

 	(void) TclPushStackFrame(interp, &framePtr,
		(Tcl_Namespace *) nsPtr, /* isProcCallFrame */ 0);


	/*
	 * TIP #280: We get the invoking context from the cmdFrame which
	 * was saved by 'Tcl_ProcObjCmd' (using linePBodyPtr).
	 */

	hePtr = Tcl_FindHashEntry(iPtr->linePBodyPtr, (char *) procPtr);


	/*
	 * Constructed saved frame has body as word 0. See Tcl_ProcObjCmd.
	 */

	iPtr->invokeWord = 0;
	iPtr->invokeCmdFramePtr =
		(hePtr ? (CmdFrame *) Tcl_GetHashValue(hePtr) : NULL);
	(void) tclByteCodeType.setFromAnyProc(interp, bodyPtr);
	iPtr->invokeCmdFramePtr = NULL;
	TclPopStackFrame(interp);


 	iPtr->compiledProcPtr = saveProcPtr;














    } else if (codePtr->nsEpoch != nsPtr->resolverEpoch) {
	/*
	 * The resolver epoch has changed, but we only need to invalidate the
	 * resolver cache.
	 */

	codePtr->nsEpoch = nsPtr->resolverEpoch;
	codePtr->flags |= TCL_BYTECODE_RESOLVE_VARS;
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------

	iPtr->ensembleRewrite.sourceObjs = objv;
	iPtr->ensembleRewrite.numRemovedObjs = 1;
	iPtr->ensembleRewrite.numInsertedObjs = 0;
    } else {
	iPtr->ensembleRewrite.numInsertedObjs -= 1;
    }

    result = PushProcCallFrame((ClientData) procPtr, interp, objc, objv, 1);
    if (result == TCL_OK) {
	result = TclObjInterpProcCore(interp, objv[1], 2, &MakeLambdaError);
    }

    if (isRootEnsemble) {
	iPtr->ensembleRewrite.sourceObjs = NULL;
	iPtr->ensembleRewrite.numRemovedObjs = 0;
	iPtr->ensembleRewrite.numInsertedObjs = 0;
    }