tclfilename.c

linux系统下的音频通信

/* 
 * tclFileName.c --
 *
 *	This file contains routines for converting file names betwen
 *	native and network form.
 *
 * Copyright (c) 1995-1996 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * SCCS: @(#) tclFileName.c 1.32 97/08/19 18:44:03
 */

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

/*
 * This variable indicates whether the cleanup procedure has been
 * registered for this file yet.
 */

static int initialized = 0;

/*
 * The following regular expression matches the root portion of a Windows
 * absolute or volume relative path.  It will match both UNC and drive relative
 * paths.
 */

#define WIN_ROOT_PATTERN "^(([a-zA-Z]:)|[/\\][/\\]+([^/\\]+)[/\\]+([^/\\]+)|([/\\]))([/\\])*"

/*
 * The following regular expression matches the root portion of a Macintosh
 * absolute path.  It will match degenerate Unix-style paths, tilde paths,
 * Unix-style paths, and Mac paths.
 */

#define MAC_ROOT_PATTERN "^((/+([.][.]?/+)*([.][.]?)?)|(~[^:/]*)(/[^:]*)?|(~[^:]*)(:.*)?|/+([.][.]?/+)*([^:/]+)(/[^:]*)?|([^:]+):.*)$"

/*
 * The following variables are used to hold precompiled regular expressions
 * for use in filename matching.
 */

static regexp *winRootPatternPtr = NULL;
static regexp *macRootPatternPtr = NULL;

/*
 * The following variable is set in the TclPlatformInit call to one
 * of: TCL_PLATFORM_UNIX, TCL_PLATFORM_MAC, or TCL_PLATFORM_WINDOWS.
 */

TclPlatformType tclPlatform = TCL_PLATFORM_UNIX;

/*
 * Prototypes for local procedures defined in this file:
 */

static char *		DoTildeSubst _ANSI_ARGS_((Tcl_Interp *interp,
			    char *user, Tcl_DString *resultPtr));
static char *		ExtractWinRoot _ANSI_ARGS_((char *path,
			    Tcl_DString *resultPtr, int offset));
static void		FileNameCleanup _ANSI_ARGS_((ClientData clientData));
static int		SkipToChar _ANSI_ARGS_((char **stringPtr,
			    char *match));
static char *		SplitMacPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));
static char *		SplitWinPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));
static char *		SplitUnixPath _ANSI_ARGS_((char *path,
			    Tcl_DString *bufPtr));

/*
 *----------------------------------------------------------------------
 *
 * FileNameCleanup --
 *
 *	This procedure is a Tcl_ExitProc used to clean up the static
 *	data structures used in this file.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Deallocates storage used by the procedures in this file.
 *
 *----------------------------------------------------------------------
 */

static void
FileNameCleanup(clientData)
    ClientData clientData;	/* Not used. */
{
    if (winRootPatternPtr != NULL) {
	ckfree((char *)winRootPatternPtr);
        winRootPatternPtr = (regexp *) NULL;
    }
    if (macRootPatternPtr != NULL) {
	ckfree((char *)macRootPatternPtr);
        macRootPatternPtr = (regexp *) NULL;
    }
    initialized = 0;
}

/*
 *----------------------------------------------------------------------
 *
 * ExtractWinRoot --
 *
 *	Matches the root portion of a Windows path and appends it
 *	to the specified Tcl_DString.
 *	
 * Results:
 *	Returns the position in the path immediately after the root
 *	including any trailing slashes.
 *	Appends a cleaned up version of the root to the Tcl_DString
 *	at the specified offest.
 *
 * Side effects:
 *	Modifies the specified Tcl_DString.
 *
 *----------------------------------------------------------------------
 */

static char *
ExtractWinRoot(path, resultPtr, offset)
    char *path;			/* Path to parse. */
    Tcl_DString *resultPtr;	/* Buffer to hold result. */
    int offset;			/* Offset in buffer where result should be
				 * stored. */
{
    int length;

    /*
     * Initialize the path name parser for Windows path names.
     */

    if (winRootPatternPtr == NULL) {
	winRootPatternPtr = TclRegComp(WIN_ROOT_PATTERN);
	if (!initialized) {
	    Tcl_CreateExitHandler(FileNameCleanup, NULL);
	    initialized = 1;
	}
    }

    /*
     * Match the root portion of a Windows path name.
     */

    if (!TclRegExec(winRootPatternPtr, path, path)) {
	return path;
    }

    Tcl_DStringSetLength(resultPtr, offset);

    if (winRootPatternPtr->startp[2] != NULL) {
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[2], 2);
	if (winRootPatternPtr->startp[6] != NULL) {
	    Tcl_DStringAppend(resultPtr, "/", 1);
	}
    } else if (winRootPatternPtr->startp[4] != NULL) {
	Tcl_DStringAppend(resultPtr, "//", 2);
	length = winRootPatternPtr->endp[3]
	    - winRootPatternPtr->startp[3];
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[3], length);
	Tcl_DStringAppend(resultPtr, "/", 1);
	length = winRootPatternPtr->endp[4]
	    - winRootPatternPtr->startp[4];
	Tcl_DStringAppend(resultPtr, winRootPatternPtr->startp[4], length);
    } else {
	Tcl_DStringAppend(resultPtr, "/", 1);
    }
    return winRootPatternPtr->endp[0];
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetPathType --
 *
 *	Determines whether a given path is relative to the current
 *	directory, relative to the current volume, or absolute.
 *
 * Results:
 *	Returns one of TCL_PATH_ABSOLUTE, TCL_PATH_RELATIVE, or
 *	TCL_PATH_VOLUME_RELATIVE.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

Tcl_PathType
Tcl_GetPathType(path)
    char *path;
{
    Tcl_PathType type = TCL_PATH_ABSOLUTE;

    switch (tclPlatform) {
   	case TCL_PLATFORM_UNIX:
	    /*
	     * Paths that begin with / or ~ are absolute.
	     */

	    if ((path[0] != '/') && (path[0] != '~')) {
		type = TCL_PATH_RELATIVE;
	    }
	    break;

	case TCL_PLATFORM_MAC:
	    if (path[0] == ':') {
		type = TCL_PATH_RELATIVE;
	    } else if (path[0] != '~') {

		/*
		 * Since we have eliminated the easy cases, use the
		 * root pattern to look for the other types.
		 */

		if (!macRootPatternPtr) {
		    macRootPatternPtr = TclRegComp(MAC_ROOT_PATTERN);
		    if (!initialized) {
			Tcl_CreateExitHandler(FileNameCleanup, NULL);
			initialized = 1;
		    }
		}
		if (!TclRegExec(macRootPatternPtr, path, path)
			|| (macRootPatternPtr->startp[2] != NULL)) {
		    type = TCL_PATH_RELATIVE;
		}
	    }
	    break;
	
	case TCL_PLATFORM_WINDOWS:
	    if (path[0] != '~') {

		/*
		 * Since we have eliminated the easy cases, check for
		 * drive relative paths using the regular expression.
		 */

		if (!winRootPatternPtr) {
		    winRootPatternPtr = TclRegComp(WIN_ROOT_PATTERN);
		    if (!initialized) {
			Tcl_CreateExitHandler(FileNameCleanup, NULL);
			initialized = 1;
		    }
		}
		if (TclRegExec(winRootPatternPtr, path, path)) {
		    if (winRootPatternPtr->startp[5]
			    || (winRootPatternPtr->startp[2]
				    && !(winRootPatternPtr->startp[6]))) {
			type = TCL_PATH_VOLUME_RELATIVE;
		    }
		} else {
		    type = TCL_PATH_RELATIVE;
		}
	    }
	    break;
    }
    return type;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SplitPath --
 *
 *	Split a path into a list of path components.  The first element
 *	of the list will have the same path type as the original path.
 *
 * Results:
 *	Returns a standard Tcl result.  The interpreter result contains
 *	a list of path components.
 *	*argvPtr will be filled in with the address of an array
 *	whose elements point to the elements of path, in order.
 *	*argcPtr will get filled in with the number of valid elements
 *	in the array.  A single block of memory is dynamically allocated
 *	to hold both the argv array and a copy of the path elements.
 *	The caller must eventually free this memory by calling ckfree()
 *	on *argvPtr.  Note:  *argvPtr and *argcPtr are only modified
 *	if the procedure returns normally.
 *
 * Side effects:
 *	Allocates memory.
 *
 *----------------------------------------------------------------------
 */

void
Tcl_SplitPath(path, argcPtr, argvPtr)
    char *path;			/* Pointer to string containing a path. */
    int *argcPtr;		/* Pointer to location to fill in with
				 * the number of elements in the path. */
    char ***argvPtr;		/* Pointer to place to store pointer to array
				 * of pointers to path elements. */
{
    int i, size;
    char *p;
    Tcl_DString buffer;
    Tcl_DStringInit(&buffer);

    /*
     * Perform platform specific splitting.  These routines will leave the
     * result in the specified buffer.  Individual elements are terminated
     * with a null character.
     */

    p = NULL;			/* Needed only to prevent gcc warnings. */
    switch (tclPlatform) {
   	case TCL_PLATFORM_UNIX:
	    p = SplitUnixPath(path, &buffer);
	    break;

	case TCL_PLATFORM_WINDOWS:
	    p = SplitWinPath(path, &buffer);
	    break;
	    
	case TCL_PLATFORM_MAC:
	    p = SplitMacPath(path, &buffer);
	    break;
    }

    /*
     * Compute the number of elements in the result.
     */

    size = Tcl_DStringLength(&buffer);
    *argcPtr = 0;
    for (i = 0; i < size; i++) {
	if (p[i] == '\0') {
	    (*argcPtr)++;
	}
    }
    
    /*
     * Allocate a buffer large enough to hold the contents of the
     * DString plus the argv pointers and the terminating NULL pointer.
     */

    *argvPtr = (char **) ckalloc((unsigned)
	    ((((*argcPtr) + 1) * sizeof(char *)) + size));

    /*
     * Position p after the last argv pointer and copy the contents of
     * the DString.
     */

    p = (char *) &(*argvPtr)[(*argcPtr) + 1];
    memcpy((VOID *) p, (VOID *) Tcl_DStringValue(&buffer), (size_t) size);

    /*
     * Now set up the argv pointers.
     */

    for (i = 0; i < *argcPtr; i++) {
	(*argvPtr)[i] = p;
	while ((*p++) != '\0') {}
    }
    (*argvPtr)[i] = NULL;

    Tcl_DStringFree(&buffer);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitUnixPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Unix paths.
 *
 * Results:
 *	Stores a null separated array of strings in the specified
 *	Tcl_DString.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitUnixPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int length;
    char *p, *elementStart;

    /*
     * Deal with the root directory as a special case.
     */

    if (path[0] == '/') {
	Tcl_DStringAppend(bufPtr, "/", 2);
	p = path+1;
    } else {
	p = path;
    }

    /*
     * Split on slashes.  Embedded elements that start with tilde will be
     * prefixed with "./" so they are not affected by tilde substitution.
     */

    for (;;) {
	elementStart = p;
	while ((*p != '\0') && (*p != '/')) {
	    p++;
	}
	length = p - elementStart;
	if (length > 0) {
	    if ((elementStart[0] == '~') && (elementStart != path)) {
		Tcl_DStringAppend(bufPtr, "./", 2);
	    }
	    Tcl_DStringAppend(bufPtr, elementStart, length);
	    Tcl_DStringAppend(bufPtr, "", 1);
	}
	if (*p++ == '\0') {
	    break;
	}
    }
    return Tcl_DStringValue(bufPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitWinPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Windows paths.
 *
 * Results:
 *	Stores a null separated array of strings in the specified
 *	Tcl_DString.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitWinPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int length;
    char *p, *elementStart;

    p = ExtractWinRoot(path, bufPtr, 0);

    /*
     * Terminate the root portion, if we matched something.
     */

    if (p != path) {
	Tcl_DStringAppend(bufPtr, "", 1);
    }

    /*
     * Split on slashes.  Embedded elements that start with tilde will be
     * prefixed with "./" so they are not affected by tilde substitution.
     */

    do {
	elementStart = p;
	while ((*p != '\0') && (*p != '/') && (*p != '\\')) {
	    p++;
	}
	length = p - elementStart;
	if (length > 0) {
	    if ((elementStart[0] == '~') && (elementStart != path)) {
		Tcl_DStringAppend(bufPtr, "./", 2);
	    }
	    Tcl_DStringAppend(bufPtr, elementStart, length);
	    Tcl_DStringAppend(bufPtr, "", 1);
	}
    } while (*p++ != '\0');

    return Tcl_DStringValue(bufPtr);
}

/*
 *----------------------------------------------------------------------
 *
 * SplitMacPath --
 *
 *	This routine is used by Tcl_SplitPath to handle splitting
 *	Macintosh paths.
 *
 * Results:
 *	Returns a newly allocated argv array.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
SplitMacPath(path, bufPtr)
    char *path;			/* Pointer to string containing a path. */
    Tcl_DString *bufPtr;	/* Pointer to DString to use for the result. */
{
    int isMac = 0;		/* 1 if is Mac-style, 0 if Unix-style path. */
    int i, length;
    char *p, *elementStart;

    /*
     * Initialize the path name parser for Macintosh path names.
     */

    if (macRootPatternPtr == NULL) {
	macRootPatternPtr = TclRegComp(MAC_ROOT_PATTERN);
	if (!initialized) {
	    Tcl_CreateExitHandler(FileNameCleanup, NULL);
	    initialized = 1;
	}
    }

    /*
     * Match the root portion of a Mac path name.
     */

    i = 0;			/* Needed only to prevent gcc warnings. */
    if (TclRegExec(macRootPatternPtr, path, path) == 1) {
	/*
	 * Treat degenerate absolute paths like / and /../.. as
	 * Mac relative file names for lack of anything else to do.
	 */

	if (macRootPatternPtr->startp[2] != NULL) {
	    Tcl_DStringAppend(bufPtr, ":", 1);
	    Tcl_DStringAppend(bufPtr, path, macRootPatternPtr->endp[0]
		    - macRootPatternPtr->startp[0] + 1);
	    return Tcl_DStringValue(bufPtr);