tclcmdil.c

tcl源码详细资料

#ifndef EXCLUDE_TCL

/* 
 * tclCmdIL.c --
 *
 *	This file contains the top-level command routines for most of
 *	the Tcl built-in commands whose names begin with the letters
 *	I through L.  It contains only commands in the generic core
 *	(i.e. those that don't depend much upon UNIX facilities).
 *
 * Copyright 1987-1991 Regents of the University of California
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies.  The University of California
 * makes no representations about the suitability of this
 * software for any purpose.  It is provided "as is" without
 * express or implied warranty.
 */

#include "tclInt.h"

/*
 * Forward declarations for procedures defined in this file:
 */

static int		SortCompareProc _ANSI_ARGS_((CONST VOID *first,
			    CONST VOID *second));

/*
 *----------------------------------------------------------------------
 *
 * Tcl_IfCmd --
 *
 *	This procedure is invoked to process the "if" 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_IfCmd(dummy, interp, argc, argv)
    ClientData dummy;			/* Not used. */
    Tcl_Interp *interp;			/* Current interpreter. */
    int argc;				/* Number of arguments. */
    char **argv;			/* Argument strings. */
{
    int i, result, value;

    i = 1;
    while (1) {
	/*
	 * At this point in the loop, argv and argc refer to an expression
	 * to test, either for the main expression or an expression
	 * following an "elseif".  The arguments after the expression must
	 * be "then" (optional) and a script to execute if the expression is
	 * true.
	 */

	if (i >= argc) {
	    Tcl_AppendResult(interp, "wrong # args: no expression after \"",
		    argv[i-1], "\" argument", (char *) NULL);
	    return TCL_ERROR;
	}
	result = Tcl_ExprBoolean(interp, argv[i], &value);
	if (result != TCL_OK) {
	    return result;
	}
	i++;
	if ((i < argc) && (strcmp(argv[i], "then") == 0)) {
	    i++;
	}
	if (i >= argc) {
	    Tcl_AppendResult(interp, "wrong # args: no script following \"",
		    argv[i-1], "\" argument", (char *) NULL);
	    return TCL_ERROR;
	}
	if (value) {
	    return Tcl_Eval(interp, argv[i], 0, (char **) NULL);
	}

	/*
	 * The expression evaluated to false.  Skip the command, then
	 * see if there is an "else" or "elseif" clause.
	 */

	i++;
	if (i >= argc) {
	    return TCL_OK;
	}
	if ((argv[i][0] == 'e') && (strcmp(argv[i], "elseif") == 0)) {
	    i++;
	    continue;
	}
	break;
    }

    /*
     * Couldn't find a "then" or "elseif" clause to execute.  Check now
     * for an "else" clause.  We know that there's at least one more
     * argument when we get here.
     */

    if (strcmp(argv[i], "else") == 0) {
	i++;
	if (i >= argc) {
	    Tcl_AppendResult(interp,
		    "wrong # args: no script following \"else\" argument",
		    (char *) NULL);
	    return TCL_ERROR;
	}
    }
    return Tcl_Eval(interp, argv[i], 0, (char **) NULL);
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_IncrCmd --
 *
 *	This procedure is invoked to process the "incr" 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_IncrCmd(dummy, interp, argc, argv)
    ClientData dummy;			/* Not used. */
    Tcl_Interp *interp;			/* Current interpreter. */
    int argc;				/* Number of arguments. */
    char **argv;			/* Argument strings. */
{
    long value;
    char *oldString, *result;
    char newString[30];

    if ((argc != 2) && (argc != 3)) {
	Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		" varName ?increment?\"", (char *) NULL);
	return TCL_ERROR;
    }

    oldString = Tcl_GetVar(interp, argv[1], TCL_LEAVE_ERR_MSG);
    if (oldString == NULL) {
	return TCL_ERROR;
    }
    if (Tcl_GetInt(interp, oldString, &value) != TCL_OK) {
	Tcl_AddErrorInfo(interp,
		"\n    (reading value of variable to increment)");
	return TCL_ERROR;
    }
    if (argc == 2) {
	value += 1;
    } else {
	long increment;

	if (Tcl_GetInt(interp, argv[2], &increment) != TCL_OK) {
	    Tcl_AddErrorInfo(interp,
		    "\n    (reading increment)");
	    return TCL_ERROR;
	}
	value += increment;
    }
    sprintf(newString, "%ld", value);
    result = Tcl_SetVar(interp, argv[1], newString, TCL_LEAVE_ERR_MSG);
    if (result == NULL) {
	return TCL_ERROR;
    }
    interp->result = result;
    return TCL_OK; 
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_InfoCmd --
 *
 *	This procedure is invoked to process the "info" 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_InfoCmd(dummy, interp, argc, argv)
    ClientData dummy;			/* Not used. */
    Tcl_Interp *interp;			/* Current interpreter. */
    int argc;				/* Number of arguments. */
    char **argv;			/* Argument strings. */
{
    register Interp *iPtr = (Interp *) interp;
    int length;
    char c;
    Arg *argPtr;
    Proc *procPtr;
    Var *varPtr;
    Command *cmdPtr;
    Tcl_HashEntry *hPtr;
    Tcl_HashSearch search;

    if (argc < 2) {
	Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		" option ?arg arg ...?\"", (char *) NULL);
	return TCL_ERROR;
    }
    c = argv[1][0];
    length = strlen(argv[1]);
    if ((c == 'a') && (strncmp(argv[1], "args", length)) == 0) {
	if (argc != 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"",
		    argv[0], " args procname\"", (char *) NULL);
	    return TCL_ERROR;
	}
	procPtr = TclFindProc(iPtr, argv[2]);
	if (procPtr == NULL) {
	    infoNoSuchProc:
	    Tcl_AppendResult(interp, "\"", argv[2],
		    "\" isn't a procedure", (char *) NULL);
	    return TCL_ERROR;
	}
	for (argPtr = procPtr->argPtr; argPtr != NULL;
		argPtr = argPtr->nextPtr) {
	    Tcl_AppendElement(interp, argPtr->name, 0);
	}
	return TCL_OK;
    } else if ((c == 'b') && (strncmp(argv[1], "body", length)) == 0) {
	if (argc != 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " body procname\"", (char *) NULL);
	    return TCL_ERROR;
	}
	procPtr = TclFindProc(iPtr, argv[2]);
	if (procPtr == NULL) {
	    goto infoNoSuchProc;
	}
	iPtr->result = procPtr->command;
	return TCL_OK;
    } else if ((c == 'c') && (strncmp(argv[1], "cmdcount", length) == 0)
	    && (length >= 2)) {
	if (argc != 2) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " cmdcount\"", (char *) NULL);
	    return TCL_ERROR;
	}
	sprintf(iPtr->result, "%d", iPtr->cmdCount);
	return TCL_OK;
    } else if ((c == 'c') && (strncmp(argv[1], "commands", length) == 0)
	    && (length >= 4)) {
	if (argc > 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " commands [pattern]\"", (char *) NULL);
	    return TCL_ERROR;
	}
	for (hPtr = Tcl_FirstHashEntry(&iPtr->commandTable, &search);
		hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
	    char *name = Tcl_GetHashKey(&iPtr->commandTable, hPtr);
	    if ((argc == 3) && !Tcl_StringMatch(name, argv[2])) {
		continue;
	    }
	    Tcl_AppendElement(interp, name, 0);
	}
	return TCL_OK;
    } else if ((c == 'c') && (strncmp(argv[1], "complete", length) == 0)
	    && (length >= 4)) {
	if (argc != 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " complete command\"", (char *) NULL);
	    return TCL_ERROR;
	}
	if (Tcl_CommandComplete(argv[2])) {
	    interp->result = "1";
	} else {
	    interp->result = "0";
	}
	return TCL_OK;
    } else if ((c == 'd') && (strncmp(argv[1], "default", length)) == 0) {
	if (argc != 5) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"",
		    argv[0], " default procname arg varname\"",
		    (char *) NULL);
	    return TCL_ERROR;
	}
	procPtr = TclFindProc(iPtr, argv[2]);
	if (procPtr == NULL) {
	    goto infoNoSuchProc;
	}
	for (argPtr = procPtr->argPtr; ; argPtr = argPtr->nextPtr) {
	    if (argPtr == NULL) {
		Tcl_AppendResult(interp, "procedure \"", argv[2],
			"\" doesn't have an argument \"", argv[3],
			"\"", (char *) NULL);
		return TCL_ERROR;
	    }
	    if (strcmp(argv[3], argPtr->name) == 0) {
		if (argPtr->defValue != NULL) {
		    if (Tcl_SetVar((Tcl_Interp *) iPtr, argv[4],
			    argPtr->defValue, 0) == NULL) {
			defStoreError:
			Tcl_AppendResult(interp,
				"couldn't store default value in variable \"",
				argv[4], "\"", (char *) NULL);
			return TCL_ERROR;
		    }
		    iPtr->result = "1";
		} else {
		    if (Tcl_SetVar((Tcl_Interp *) iPtr, argv[4], "", 0)
			    == NULL) {
			goto defStoreError;
		    }
		    iPtr->result = "0";
		}
		return TCL_OK;
	    }
	}
    } else if ((c == 'e') && (strncmp(argv[1], "exists", length) == 0)) {
	char *p;
	if (argc != 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " exists varName\"", (char *) NULL);
	    return TCL_ERROR;
	}
	p = Tcl_GetVar((Tcl_Interp *) iPtr, argv[2], 0);

	/*
	 * The code below handles the special case where the name is for
	 * an array:  Tcl_GetVar will reject this since you can't read
	 * an array variable without an index.
	 */

	if (p == NULL) {
	    Tcl_HashEntry *hPtr;
	    Var *varPtr;

	    if (strchr(argv[2], '(') != NULL) {
		noVar:
		iPtr->result = "0";
		return TCL_OK;
	    }
	    if (iPtr->varFramePtr == NULL) {
		hPtr = Tcl_FindHashEntry(&iPtr->globalTable, argv[2]);
	    } else {
		hPtr = Tcl_FindHashEntry(&iPtr->varFramePtr->varTable, argv[2]);
	    }
	    if (hPtr == NULL) {
		goto noVar;
	    }
	    varPtr = (Var *) Tcl_GetHashValue(hPtr);
	    if (varPtr->flags & VAR_UPVAR) {
		varPtr = (Var *) Tcl_GetHashValue(varPtr->value.upvarPtr);
	    }
	    if (!(varPtr->flags & VAR_ARRAY)) {
		goto noVar;
	    }
	}
	iPtr->result = "1";
	return TCL_OK;
    } else if ((c == 'g') && (strncmp(argv[1], "globals", length) == 0)) {
	char *name;

	if (argc > 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " globals [pattern]\"", (char *) NULL);
	    return TCL_ERROR;
	}
	for (hPtr = Tcl_FirstHashEntry(&iPtr->globalTable, &search);
		hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
	    varPtr = (Var *) Tcl_GetHashValue(hPtr);
	    if (varPtr->flags & VAR_UNDEFINED) {
		continue;
	    }
	    name = Tcl_GetHashKey(&iPtr->globalTable, hPtr);
	    if ((argc == 3) && !Tcl_StringMatch(name, argv[2])) {
		continue;
	    }
	    Tcl_AppendElement(interp, name, 0);
	}
	return TCL_OK;
    } else if ((c == 'l') && (strncmp(argv[1], "level", length) == 0)
	    && (length >= 2)) {
	if (argc == 2) {
	    if (iPtr->varFramePtr == NULL) {
		iPtr->result = "0";
	    } else {
		sprintf(iPtr->result, "%d", iPtr->varFramePtr->level);
	    }
	    return TCL_OK;
	} else if (argc == 3) {
	    long level;
	    CallFrame *framePtr;

	    if (Tcl_GetInt(interp, argv[2], &level) != TCL_OK) {
		return TCL_ERROR;
	    }
	    if (level <= 0) {
		if (iPtr->varFramePtr == NULL) {
		    levelError:
		    Tcl_AppendResult(interp, "bad level \"", argv[2],
			    "\"", (char *) NULL);
		    return TCL_ERROR;
		}
		level += iPtr->varFramePtr->level;
	    }
	    for (framePtr = iPtr->varFramePtr; framePtr != NULL;
		    framePtr = framePtr->callerVarPtr) {
		if (framePtr->level == level) {
		    break;
		}
	    }
	    if (framePtr == NULL) {
		goto levelError;
	    }
	    iPtr->result = Tcl_Merge(framePtr->argc, framePtr->argv);
	    iPtr->freeProc = (Tcl_FreeProc *) free;
	    return TCL_OK;
	}
	Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		" level [number]\"", (char *) NULL);
	return TCL_ERROR;
    } else if ((c == 'l') && (strncmp(argv[1], "library", length) == 0)
	    && (length >= 2)) {
	if (argc != 2) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " library\"", (char *) NULL);
	    return TCL_ERROR;
	}
	interp->result = getenv("TCL_LIBRARY");
	if (interp->result == NULL) {
#ifdef TCL_LIBRARY
	    interp->result = TCL_LIBRARY;
#else
	    interp->result = "there is no Tcl library at this installation";
	    return TCL_ERROR;
#endif
	}
	return TCL_OK;
    } else if ((c == 'l') && (strncmp(argv[1], "locals", length) == 0)
	    && (length >= 2)) {
	char *name;

	if (argc > 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " locals [pattern]\"", (char *) NULL);
	    return TCL_ERROR;
	}
	if (iPtr->varFramePtr == NULL) {
	    return TCL_OK;
	}
	for (hPtr = Tcl_FirstHashEntry(&iPtr->varFramePtr->varTable, &search);
		hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
	    varPtr = (Var *) Tcl_GetHashValue(hPtr);
	    if (varPtr->flags & (VAR_UNDEFINED|VAR_UPVAR)) {
		continue;
	    }
	    name = Tcl_GetHashKey(&iPtr->varFramePtr->varTable, hPtr);
	    if ((argc == 3) && !Tcl_StringMatch(name, argv[2])) {
		continue;
	    }
	    Tcl_AppendElement(interp, name, 0);
	}
	return TCL_OK;
    } else if ((c == 'p') && (strncmp(argv[1], "procs", length)) == 0) {
	if (argc > 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
		    " procs [pattern]\"", (char *) NULL);
	    return TCL_ERROR;
	}
	for (hPtr = Tcl_FirstHashEntry(&iPtr->commandTable, &search);
		hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
	    char *name = Tcl_GetHashKey(&iPtr->commandTable, hPtr);

	    cmdPtr = (Command *) Tcl_GetHashValue(hPtr);
	    if (!TclIsProc(cmdPtr)) {
		continue;
	    }
	    if ((argc == 3) && !Tcl_StringMatch(name, argv[2])) {
		continue;
	    }
	    Tcl_AppendElement(interp, name, 0);
	}
	return TCL_OK;
    } else if ((c == 's') && (strncmp(argv[1], "script", length) == 0)) {
	if (argc != 2) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"",
		    argv[0], " script\"", (char *) NULL);
	    return TCL_ERROR;
	}
	if (iPtr->scriptFile != NULL) {
	    interp->result = iPtr->scriptFile;
	}
	return TCL_OK;
    } else if ((c == 't') && (strncmp(argv[1], "tclversion", length) == 0)) {
	if (argc != 2) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"",
		    argv[0], " tclversion\"", (char *) NULL);
	    return TCL_ERROR;
	}

	/*
	 * Note:  TCL_VERSION below is expected to be set with a "-D"
	 * switch in the Makefile.
	 */

	strcpy(iPtr->result, TCL_VERSION);
	return TCL_OK;
    } else if ((c == 'v') && (strncmp(argv[1], "vars", length)) == 0) {
	Tcl_HashTable *tablePtr;
	char *name;

	if (argc > 3) {
	    Tcl_AppendResult(interp, "wrong # args: should be \"",
		    argv[0], " vars [pattern]\"", (char *) NULL);
	    return TCL_ERROR;
	}
	if (iPtr->varFramePtr == NULL) {
	    tablePtr = &iPtr->globalTable;
	} else {
	    tablePtr = &iPtr->varFramePtr->varTable;
	}
	for (hPtr = Tcl_FirstHashEntry(tablePtr, &search);
		hPtr != NULL; hPtr = Tcl_NextHashEntry(&search)) {
	    varPtr = (Var *) Tcl_GetHashValue(hPtr);
	    if (varPtr->flags & VAR_UNDEFINED) {
		continue;
	    }
	    name = Tcl_GetHashKey(tablePtr, hPtr);
	    if ((argc == 3) && !Tcl_StringMatch(name, argv[2])) {
		continue;
	    }
	    Tcl_AppendElement(interp, name, 0);
	}
	return TCL_OK;
    } else {
	Tcl_AppendResult(interp, "bad option \"", argv[1],
		"\": should be args, body, cmdcount, commands, ",
		"complete, default, ",
		"exists, globals, level, library, locals, procs, ",
		"script, tclversion, or vars",
		(char *) NULL);
	return TCL_ERROR;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_JoinCmd --
 *
 *	This procedure is invoked to process the "join" 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_JoinCmd(dummy, interp, argc, argv)
    ClientData dummy;			/* Not used. */
    Tcl_Interp *interp;			/* Current interpreter. */