tclbasic.c

linux系统下的音频通信

    Namespace *nsPtr;
    Tcl_HashEntry *hPtr;
    Tcl_HashTable *hTblPtr;
    int new;

    if (iPtr->flags & DELETED) {
        /*
         * The interpreter is being deleted. Do not create any new
         * structures, because it is not safe to modify the interpreter.
         */
        
        return TCL_ERROR;
    }

    /*
     * Check that we have a regular name for the command
     * (that the user is not trying to do an expose and a rename
     *  (to another namespace) at the same time)
     */

    if (strstr(cmdName, "::") != NULL) {
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                "can not expose to a namespace ",
		"(use expose to toplevel, then rename)",
                 (char *) NULL);
        return TCL_ERROR;
    }

    /*
     * Find the hash table for the hidden commands; error out if there
     * is none.
     */

    hTblPtr = (Tcl_HashTable *) Tcl_GetAssocData(interp, "tclHiddenCmds",
            NULL);
    if (hTblPtr == NULL) {
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                "unknown hidden command \"", hiddenCmdToken,
                "\"", (char *) NULL);
        return TCL_ERROR;
    }
        
    /*
     * Get the command from the hidden command table:
     */

    hPtr = Tcl_FindHashEntry(hTblPtr, hiddenCmdToken);
    if (hPtr == (Tcl_HashEntry *) NULL) {
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                "unknown hidden command \"", hiddenCmdToken,
                "\"", (char *) NULL);
        return TCL_ERROR;
    }
    cmdPtr = (Command *) Tcl_GetHashValue(hPtr);
    

    /*
     * Check that we have a true global namespace
     * command (enforced by Tcl_HideCommand() but let's double
     * check. (If it was not, we would not really know how to
     * handle it).
     */
    if ( cmdPtr->nsPtr != iPtr->globalNsPtr ) {
	/* 
	 * This case is theoritically impossible,
	 * we might rather panic() than 'nicely' erroring out ?
	 */
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                "trying to expose a non global command name space command",
		(char *) NULL);
        return TCL_ERROR;
    }
    
    /* This is the global table */
    nsPtr = cmdPtr->nsPtr;

    /*
     * It is an error to overwrite an existing exposed command as a result
     * of exposing a previously hidden command.
     */

    hPtr = Tcl_CreateHashEntry(&nsPtr->cmdTable, cmdName, &new);
    if (!new) {
        Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
                "exposed command \"", cmdName,
                "\" already exists", (char *) NULL);
        return TCL_ERROR;
    }

    /*
     * Remove the hash entry for the command from the interpreter hidden
     * command table.
     */

    if (cmdPtr->hPtr != NULL) {
        Tcl_DeleteHashEntry(cmdPtr->hPtr);
        cmdPtr->hPtr = NULL;
    }

    /*
     * Now link the hash table entry with the command structure.
     * This is like creating a new command, so deal with any shadowing
     * of commands in the global namespace.
     */
    
    cmdPtr->hPtr = hPtr;

    Tcl_SetHashValue(hPtr, (ClientData) cmdPtr);

    /*
     * Not needed as we are only in the global namespace
     * (but would be needed again if we supported namespace command hiding)
     *
     * TclResetShadowedCmdRefs(interp, cmdPtr);
     */


    /*
     * If the command being exposed has a compile procedure, increment
     * interpreter's compileEpoch to invalidate its compiled code. This
     * makes sure that we don't later try to execute old code compiled
     * assuming the command is hidden. This field is checked in Tcl_EvalObj
     * and ObjInterpProc, and code whose compilation epoch doesn't match is
     * recompiled.
     */

    if (cmdPtr->compileProc != NULL) {
	iPtr->compileEpoch++;
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_CreateCommand --
 *
 *	Define a new command in a command table.
 *
 * Results:
 *	The return value is a token for the command, which can
 *	be used in future calls to Tcl_GetCommandName.
 *
 * Side effects:
 *	If a command named cmdName already exists for interp, it is deleted.
 *	In the future, when cmdName is seen as the name of a command by
 *	Tcl_Eval, proc will be called. To support the bytecode interpreter,
 *	the command is created with a wrapper Tcl_ObjCmdProc
 *	(TclInvokeStringCommand) that eventially calls proc. When the
 *	command is deleted from the table, deleteProc will be called.
 *	See the manual entry for details on the calling sequence.
 *
 *----------------------------------------------------------------------
 */

Tcl_Command
Tcl_CreateCommand(interp, cmdName, proc, clientData, deleteProc)
    Tcl_Interp *interp;		/* Token for command interpreter returned by
				 * a previous call to Tcl_CreateInterp. */
    char *cmdName;		/* Name of command. If it contains namespace
				 * qualifiers, the new command is put in the
				 * specified namespace; otherwise it is put
				 * in the global namespace. */
    Tcl_CmdProc *proc;		/* Procedure to associate with cmdName. */
    ClientData clientData;	/* Arbitrary value passed to string proc. */
    Tcl_CmdDeleteProc *deleteProc;
				/* If not NULL, gives a procedure to call
				 * when this command is deleted. */
{
    Interp *iPtr = (Interp *) interp;
    ImportRef *oldRefPtr = NULL;
    Namespace *nsPtr, *dummy1, *dummy2;
    Command *cmdPtr, *refCmdPtr;
    Tcl_HashEntry *hPtr;
    char *tail;
    int new, result;
    ImportedCmdData *dataPtr;

    if (iPtr->flags & DELETED) {
	/*
	 * The interpreter is being deleted.  Don't create any new
	 * commands; it's not safe to muck with the interpreter anymore.
	 */

	return (Tcl_Command) NULL;
    }

    /*
     * Determine where the command should reside. If its name contains 
     * namespace qualifiers, we put it in the specified namespace; 
     * otherwise, we always put it in the global namespace.
     */

    if (strstr(cmdName, "::") != NULL) {
	result = TclGetNamespaceForQualName(interp, cmdName, 
                (Namespace *) NULL, CREATE_NS_IF_UNKNOWN, &nsPtr, 
                &dummy1, &dummy2, &tail);
	if ((result != TCL_OK) || (nsPtr == NULL) || (tail == NULL)) {
	    return (Tcl_Command) NULL;
	}
    } else {
	nsPtr = iPtr->globalNsPtr;
	tail = cmdName;
    }
    
    hPtr = Tcl_CreateHashEntry(&nsPtr->cmdTable, tail, &new);
    if (!new) {
	/*
	 * Command already exists. Delete the old one.
	 * Be careful to preserve any existing import links so we can
	 * restore them down below.  That way, you can redefine a
	 * command and its import status will remain intact.
	 */

	cmdPtr = (Command *) Tcl_GetHashValue(hPtr);
	oldRefPtr = cmdPtr->importRefPtr;
	cmdPtr->importRefPtr = NULL;

	Tcl_DeleteCommandFromToken(interp, (Tcl_Command) cmdPtr);
	hPtr = Tcl_CreateHashEntry(&nsPtr->cmdTable, tail, &new);
	if (!new) {
	    /*
	     * If the deletion callback recreated the command, just throw
             * away the new command (if we try to delete it again, we
             * could get stuck in an infinite loop).
	     */

	     ckfree((char*) cmdPtr);
	}
    }
    cmdPtr = (Command *) ckalloc(sizeof(Command));
    Tcl_SetHashValue(hPtr, cmdPtr);
    cmdPtr->hPtr = hPtr;
    cmdPtr->nsPtr = nsPtr;
    cmdPtr->refCount = 1;
    cmdPtr->cmdEpoch = 0;
    cmdPtr->compileProc = (CompileProc *) NULL;
    cmdPtr->objProc = TclInvokeStringCommand;
    cmdPtr->objClientData = (ClientData) cmdPtr;
    cmdPtr->proc = proc;
    cmdPtr->clientData = clientData;
    cmdPtr->deleteProc = deleteProc;
    cmdPtr->deleteData = clientData;
    cmdPtr->deleted = 0;
    cmdPtr->importRefPtr = NULL;

    /*
     * Plug in any existing import references found above.  Be sure
     * to update all of these references to point to the new command.
     */

    if (oldRefPtr != NULL) {
	cmdPtr->importRefPtr = oldRefPtr;
	while (oldRefPtr != NULL) {
	    refCmdPtr = oldRefPtr->importedCmdPtr;
	    dataPtr = (ImportedCmdData*)refCmdPtr->objClientData;
	    dataPtr->realCmdPtr = cmdPtr;
	    oldRefPtr = oldRefPtr->nextPtr;
	}
    }

    /*
     * We just created a command, so in its namespace and all of its parent
     * namespaces, it may shadow global commands with the same name. If any
     * shadowed commands are found, invalidate all cached command references
     * in the affected namespaces.
     */
    
    TclResetShadowedCmdRefs(interp, cmdPtr);
    return (Tcl_Command) cmdPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_CreateObjCommand --
 *
 *	Define a new object-based command in a command table.
 *
 * Results:
 *	The return value is a token for the command, which can
 *	be used in future calls to Tcl_NameOfCommand.
 *
 * Side effects:
 *	If no command named "cmdName" already exists for interp, one is
 *	created. Otherwise, if a command does exist, then if the
 *	object-based Tcl_ObjCmdProc is TclInvokeStringCommand, we assume
 *	Tcl_CreateCommand was called previously for the same command and
 *	just set its Tcl_ObjCmdProc to the argument "proc"; otherwise, we
 *	delete the old command.
 *
 *	In the future, during bytecode evaluation when "cmdName" is seen as
 *	the name of a command by Tcl_EvalObj or Tcl_Eval, the object-based
 *	Tcl_ObjCmdProc proc will be called. When the command is deleted from
 *	the table, deleteProc will be called. See the manual entry for
 *	details on the calling sequence.
 *
 *----------------------------------------------------------------------
 */

Tcl_Command
Tcl_CreateObjCommand(interp, cmdName, proc, clientData, deleteProc)
    Tcl_Interp *interp;		/* Token for command interpreter (returned
				 * by previous call to Tcl_CreateInterp). */
    char *cmdName;		/* Name of command. If it contains namespace
				 * qualifiers, the new command is put in the
				 * specified namespace; otherwise it is put
				 * in the global namespace. */
    Tcl_ObjCmdProc *proc;	/* Object-based procedure to associate with
				 * name. */
    ClientData clientData;	/* Arbitrary value to pass to object
    				 * procedure. */
    Tcl_CmdDeleteProc *deleteProc;
				/* If not NULL, gives a procedure to call
				 * when this command is deleted. */
{
    Interp *iPtr = (Interp *) interp;
    ImportRef *oldRefPtr = NULL;
    Namespace *nsPtr, *dummy1, *dummy2;
    Command *cmdPtr, *refCmdPtr;
    Tcl_HashEntry *hPtr;
    char *tail;
    int new, result;
    ImportedCmdData *dataPtr;

    if (iPtr->flags & DELETED) {
	/*
	 * The interpreter is being deleted.  Don't create any new
	 * commands;  it's not safe to muck with the interpreter anymore.
	 */

	return (Tcl_Command) NULL;
    }

    /*
     * Determine where the command should reside. If its name contains 
     * namespace qualifiers, we put it in the specified namespace; 
     * otherwise, we always put it in the global namespace.
     */

    if (strstr(cmdName, "::") != NULL) {
	result = TclGetNamespaceForQualName(interp, cmdName, 
                (Namespace *) NULL, CREATE_NS_IF_UNKNOWN, &nsPtr, 
                &dummy1, &dummy2, &tail);
	if ((result != TCL_OK) || (nsPtr == NULL) || (tail == NULL)) {
	    return (Tcl_Command) NULL;
	}
    } else {
	nsPtr = iPtr->globalNsPtr;
	tail = cmdName;
    }

    hPtr = Tcl_CreateHashEntry(&nsPtr->cmdTable, tail, &new);
    if (!new) {
	cmdPtr = (Command *) Tcl_GetHashValue(hPtr);

	/*
	 * Command already exists. If its object-based Tcl_ObjCmdProc is
	 * TclInvokeStringCommand, we just set its Tcl_ObjCmdProc to the
	 * argument "proc". Otherwise, we delete the old command. 
	 */

	if (cmdPtr->objProc == TclInvokeStringCommand) {
	    cmdPtr->objProc = proc;
	    cmdPtr->objClientData = clientData;
            cmdPtr->deleteProc = deleteProc;
            cmdPtr->deleteData = clientData;
	    return (Tcl_Command) cmdPtr;
	}

	/*
	 * Otherwise, we delete the old command.  Be careful to preserve
	 * any existing import links so we can restore them down below.
	 * That way, you can redefine a command and its import status
	 * will remain intact.
	 */

	oldRefPtr = cmdPtr->importRefPtr;
	cmdPtr->importRefPtr = NULL;

	Tcl_DeleteCommandFromToken(interp, (Tcl_Command) cmdPtr);
	hPtr = Tcl_CreateHashEntry(&nsPtr->cmdTable, tail, &new);
	if (!new) {
	    /*
	     * If the deletion callback recreated the command, just throw
	     * away the new command (if we try to delete it again, we
	     * could get stuck in an infinite loop).
	     */

	     ckfree((char *) Tcl_GetHashValue(hPtr));
	}
    }
    cmdPtr = (Command *) ckalloc(sizeof(Command));
    Tcl_SetHashValue(hPtr, cmdPtr);
    cmdPtr->hPtr = hPtr;
    cmdPtr->nsPtr = nsPtr;
    cmdPtr->refCount = 1;
    cmdPtr->cmdEpoch = 0;
    cmdPtr->compileProc = (CompileProc *) NULL;
    cmdPtr->objProc = proc;
    cmdPtr->objClientData = clientData;
    cmdPtr->proc = TclInvokeObjectCommand;
    cmdPtr->clientData = (ClientData) cmdPtr;
    cmdPtr->deleteProc = deleteProc;
    cmdPtr->deleteData = clientData;
    cmdPtr->deleted = 0;
    cmdPtr->importRefPtr = NULL;

    /*
     * Plug in any existing import references found above.  Be sure
     * to update all of these references to point to the new command.
     */

    if (oldRefPtr != NULL) {
	cmdPtr->importRefPtr = oldRefPtr;
	while (oldRefPtr != NULL) {