* Copyright (c) 1994-1997 Sun Microsystems, Inc.
 * Copyright (c) 2001-2004 Vincent Darley.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#if defined(HAVE_SYS_STAT_H) && !defined _WIN32
#   include <sys/stat.h>
#endif
#include "tclInt.h"
#ifdef __WIN32__
#   include "tclWinInt.h"
#endif
#include "tclFileSystem.h"

/*
 * struct FilesystemRecord --
 *
 * A filesystem record is used to keep track of each filesystem currently
 * registered with the core, in a linked list.
 */

typedef struct FilesystemRecord {
    ClientData clientData;	/* Client specific data for the new filesystem
				 * (can be NULL) */
    const Tcl_Filesystem *fsPtr;/* Pointer to filesystem dispatch table. */
    struct FilesystemRecord *nextPtr;
				/* The next filesystem registered to Tcl, or
				 * NULL if no more. */
    struct FilesystemRecord *prevPtr;
				/* The previous filesystem registered to Tcl,
				 * or NULL if no more. */
} FilesystemRecord;

/*
 * This structure holds per-thread private copy of the current directory
 * maintained by the global cwdPathPtr. This structure holds per-thread
 * private copies of some global data. This way we avoid most of the
 * synchronization calls which boosts performance, at cost of having to update
 * this information each time the corresponding epoch counter changes.
 */

typedef struct ThreadSpecificData {
    int initialized;
    int cwdPathEpoch;
    int filesystemEpoch;
    Tcl_Obj *cwdPathPtr;
    ClientData cwdClientData;
    FilesystemRecord *filesystemList;
    int claims;
} ThreadSpecificData;

/*
 * Prototypes for functions defined later in this file.
 */

static int		EvalFileCallback(ClientData data[],
			    Tcl_Interp *interp, int result);
static FilesystemRecord*FsGetFirstFilesystem(void);
static void		FsThrExitProc(ClientData cd);
static Tcl_Obj *	FsListMounts(Tcl_Obj *pathPtr, const char *pattern);
static void		FsAddMountsToGlobResult(Tcl_Obj *resultPtr,
			    Tcl_Obj *pathPtr, const char *pattern,
			    Tcl_GlobTypeData *types);
static void		FsUpdateCwd(Tcl_Obj *cwdObj, ClientData clientData);

static void		FsRecacheFilesystemList(void);
static void		Claim(void);
static void		Disclaim(void);

static void *		DivertFindSymbol(Tcl_Interp *interp,
			    Tcl_LoadHandle loadHandle, const char *symbol);
static void		DivertUnloadFile(Tcl_LoadHandle loadHandle);

/*
 * These form part of the native filesystem support. They are needed here
 * because we have a few native filesystem functions (which are the same for

    TclpObjCreateDirectory,
    TclpObjRemoveDirectory,
    TclpObjDeleteFile,
    TclpObjCopyFile,
    TclpObjRenameFile,
    TclpObjCopyDirectory,
    TclpObjLstat,

    /* Needs casts since we're using version_2. */
    (Tcl_FSLoadFileProc *) TclpDlopen,
    (Tcl_FSGetCwdProc *) TclpGetNativeCwd,
    TclpObjChdir
};

/*
 * Define the tail of the linked list. Note that for unconventional uses of
 * Tcl without a native filesystem, we may in the future wish to modify the
 * current approach of hard-coding the native filesystem in the lookup list
 * 'filesystemList' below.
 *
 * We initialize the record so that it thinks one file uses it. This means it
 * will never be freed.
 */

static FilesystemRecord nativeFilesystemRecord = {
    NULL,
    &tclNativeFilesystem,

    NULL,
    NULL
};

/*
 * This is incremented each time we modify the linked list of filesystems. Any
 * time it changes, all cached filesystem representations are suspect and must
 * be freed. For multithreading builds, change of the filesystem epoch will
 * trigger cache cleanup in all threads.
 */

static int theFilesystemEpoch = 1;

/*
 * Stores the linked list of filesystems. A 1:1 copy of this list is also
 * maintained in the TSD for each thread. This is to avoid synchronization
 * issues.
 */

static FilesystemRecord *filesystemList = &nativeFilesystemRecord;
TCL_DECLARE_MUTEX(filesystemMutex)

/*
 * Used to implement Tcl_FSGetCwd in a file-system independent way.
 */

static Tcl_Obj *cwdPathPtr = NULL;
static int cwdPathEpoch = 0;
static ClientData cwdClientData = NULL;
TCL_DECLARE_MUTEX(cwdMutex)

static Tcl_ThreadDataKey fsDataKey;

/*
 * One of these structures is used each time we successfully load a file from
 * a file system by way of making a temporary copy of the file on the native
 * filesystem. We need to store both the actual unloadProc/clientData
 * combination which was used, and the original and modified filenames, so
 * that we can correctly undo the entire operation when we want to unload the

{
    Tcl_Obj *cwd = Tcl_FSGetCwd(interp);

    if (cwd == NULL) {
	return NULL;
    }
    Tcl_DStringInit(cwdPtr);
    TclDStringAppendObj(cwdPtr, cwd);
    Tcl_DecrRefCount(cwd);
    return Tcl_DStringValue(cwdPtr);
}

/* Obsolete */
int
Tcl_EvalFile(

    /*
     * Trash the filesystems cache.
     */

    fsRecPtr = tsdPtr->filesystemList;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = fsRecPtr->nextPtr;
	fsRecPtr->fsPtr = NULL;
	ckfree(fsRecPtr);

	fsRecPtr = tmpFsRecPtr;
    }
    tsdPtr->filesystemList = NULL;
    tsdPtr->initialized = 0;
}

int
TclFSCwdIsNative(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    if (tsdPtr->cwdClientData != NULL) {
	return 1;
    } else {
	return 0;
    }
}

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

int
TclFSCwdPointerEquals(
    Tcl_Obj **pathPtrPtr)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    Tcl_MutexLock(&cwdMutex);
    if (tsdPtr->cwdPathPtr == NULL
	    || tsdPtr->cwdPathEpoch != cwdPathEpoch) {
	if (tsdPtr->cwdPathPtr != NULL) {
	    Tcl_DecrRefCount(tsdPtr->cwdPathPtr);
	}

	    return 1;
	} else {
	    return 0;
	}
    }
}


static void
FsRecacheFilesystemList(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
    FilesystemRecord *fsRecPtr, *tmpFsRecPtr = NULL, *toFree = NULL, *list;

    /*
     * Trash the current cache.
     */

    fsRecPtr = tsdPtr->filesystemList;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = fsRecPtr->nextPtr;
	fsRecPtr->nextPtr = toFree;
	toFree = fsRecPtr;

	fsRecPtr = tmpFsRecPtr;
    }


    /*



     * Locate tail of the global filesystem list.
     */

    Tcl_MutexLock(&filesystemMutex);
    fsRecPtr = filesystemList;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = fsRecPtr;
	fsRecPtr = fsRecPtr->nextPtr;
    }

    /*
     * Refill the cache honouring the order.
     */

    list = NULL;
    fsRecPtr = tmpFsRecPtr;
    while (fsRecPtr != NULL) {
	tmpFsRecPtr = ckalloc(sizeof(FilesystemRecord));
	*tmpFsRecPtr = *fsRecPtr;
	tmpFsRecPtr->nextPtr = list;
	tmpFsRecPtr->prevPtr = NULL;

	list = tmpFsRecPtr;
	fsRecPtr = fsRecPtr->prevPtr;
    }
    tsdPtr->filesystemList = list;
    tsdPtr->filesystemEpoch = theFilesystemEpoch;
    Tcl_MutexUnlock(&filesystemMutex);

    while (toFree) {
	FilesystemRecord *next = toFree->nextPtr;
	toFree->fsPtr = NULL;
	ckfree(toFree);
	toFree = next;
    }

    /*
     * Make sure the above gets released on thread exit.
     */

    if (tsdPtr->initialized == 0) {
	Tcl_CreateThreadExitHandler(FsThrExitProc, tsdPtr);
	tsdPtr->initialized = 1;
    }
}


static FilesystemRecord *
FsGetFirstFilesystem(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);







    if (tsdPtr->filesystemList == NULL || ((tsdPtr->claims == 0)
	    && (tsdPtr->filesystemEpoch != theFilesystemEpoch))) {
	FsRecacheFilesystemList();

    }

    return tsdPtr->filesystemList;


}

/*
 * The epoch can be changed both by filesystems being added or removed and by
 * env(HOME) changing.
 */

int
TclFSEpochOk(
    int filesystemEpoch)
{
    return (filesystemEpoch == 0 || filesystemEpoch == theFilesystemEpoch);
}

static void
Claim(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    tsdPtr->claims++;
}

static void
Disclaim(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    tsdPtr->claims--;
}

int
TclFSEpoch(void)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    return tsdPtr->filesystemEpoch;
}


/*
 * If non-NULL, clientData is owned by us and must be freed later.
 */

static void
FsUpdateCwd(
    Tcl_Obj *cwdObj,
    ClientData clientData)
{
    int len;
    const char *str = NULL;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    if (cwdObj != NULL) {
	str = Tcl_GetStringFromObj(cwdObj, &len);
    }

    Tcl_MutexLock(&cwdMutex);
    if (cwdPathPtr != NULL) {

     * needed.
     */

    fsRecPtr = filesystemList;
    while (fsRecPtr != NULL) {
	FilesystemRecord *tmpFsRecPtr = fsRecPtr->nextPtr;



	/* The native filesystem is static, so we don't free it. */


	if (fsRecPtr != &nativeFilesystemRecord) {
	    ckfree(fsRecPtr);

	}
	fsRecPtr = tmpFsRecPtr;
    }
    theFilesystemEpoch++;
    filesystemList = NULL;

    /*
     * Now filesystemList is NULL. This means that any attempt to use the
     * filesystem is likely to fail.
     */

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

void
TclResetFilesystem(void)
{
    filesystemList = &nativeFilesystemRecord;
    theFilesystemEpoch++;





#ifdef __WIN32__
    /*
     * Cleans up the win32 API filesystem proc lookup table. This must happen
     * very late in finalization so that deleting of copied dlls can occur.
     */

    }

    newFilesystemPtr = ckalloc(sizeof(FilesystemRecord));

    newFilesystemPtr->clientData = clientData;
    newFilesystemPtr->fsPtr = fsPtr;








    /*
     * Is this lock and wait strictly speaking necessary? Since any iterators
     * out there will have grabbed a copy of the head of the list and be
     * iterating away from that, if we add a new element to the head of the
     * list, it can't possibly have any effect on any of their loops. In fact
     * it could be better not to wait, since we are adjusting the filesystem
     * epoch, any cached representations calculated by existing iterators are

    /*
     * Traverse the 'filesystemList' looking for the particular node whose
     * 'fsPtr' member matches 'fsPtr' and remove that one from the list.
     * Ensure that the "default" node cannot be removed.
     */

    fsRecPtr = filesystemList;
    while ((retVal == TCL_ERROR) && (fsRecPtr != &nativeFilesystemRecord)) {
	if (fsRecPtr->fsPtr == fsPtr) {
	    if (fsRecPtr->prevPtr) {
		fsRecPtr->prevPtr->nextPtr = fsRecPtr->nextPtr;
	    } else {
		filesystemList = fsRecPtr->nextPtr;
	    }
	    if (fsRecPtr->nextPtr) {
		fsRecPtr->nextPtr->prevPtr = fsRecPtr->prevPtr;
	    }

	    /*
	     * Increment the filesystem epoch counter, since existing paths
	     * might conceivably now belong to different filesystems. This
	     * should also ensure that paths which have cached the filesystem
	     * which is about to be deleted do not reference that filesystem
	     * (which would of course lead to memory exceptions).
	     */

	    theFilesystemEpoch++;



	    ckfree(fsRecPtr);


	    retVal = TCL_OK;
	} else {
	    fsRecPtr = fsRecPtr->nextPtr;
	}
    }

     * single filesystem's implementation of Tcl_FSMatchInDirectory will have
     * to deal with it for us.
     */

    cwd = Tcl_FSGetCwd(NULL);
    if (cwd == NULL) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "glob couldn't determine the current working directory",
		    -1));
	}
	return TCL_ERROR;
    }

    fsPtr = Tcl_FSGetFileSystemForPath(cwd);
    if (fsPtr != NULL && fsPtr->matchInDirectoryProc != NULL) {
	TclNewObj(tmpResultPtr);

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

int
TclFSNormalizeToUniquePath(
    Tcl_Interp *interp,		/* Used for error messages. */
    Tcl_Obj *pathPtr,		/* The path to normalize in place. */
    int startAt)		/* Start at this char-offset. */



{
    FilesystemRecord *fsRecPtr, *firstFsRecPtr;



    /*
     * Call each of the "normalise path" functions in succession. This is a
     * special case, in which if we have a native filesystem handler, we call
     * it first. This is because the root of Tcl's filesystem is always a
     * native filesystem (i.e. '/' on unix is native).
     */

    firstFsRecPtr = FsGetFirstFilesystem();

    Claim();
    for (fsRecPtr=firstFsRecPtr; fsRecPtr!=NULL; fsRecPtr=fsRecPtr->nextPtr) {
	if (fsRecPtr->fsPtr != &tclNativeFilesystem) {
	    continue;
	}

	/*
	 * TODO: Assume that we always find the native file system; it should

	/*
	 * We could add an efficiency check like this:
	 *		if (retVal == length-of(pathPtr)) {break;}
	 * but there's not much benefit.
	 */
    }
    Disclaim();

    return startAt;
}

/*
 *---------------------------------------------------------------------------
 *

	}
	return mode;

    error:
	*seekFlagPtr = 0;
	*binaryPtr = 0;
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		    "illegal access mode \"%s\"", modeString));
	}
	return -1;
    }

    /*
     * The access modes are specified using a list of POSIX modes such as
     * O_CREAT.

	    mode |= O_EXCL;

	} else if ((c == 'N') && (strcmp(flag, "NOCTTY") == 0)) {
#ifdef O_NOCTTY
	    mode |= O_NOCTTY;
#else
	    if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"access mode \"%s\" not supported by this system",
			flag));
	    }
	    ckfree(modeArgv);
	    return -1;
#endif

	} else if ((c == 'N') && (strcmp(flag, "NONBLOCK") == 0)) {
#ifdef O_NONBLOCK
	    mode |= O_NONBLOCK;
#else
	    if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"access mode \"%s\" not supported by this system",
			flag));
	    }
	    ckfree(modeArgv);
	    return -1;
#endif

	} else if ((c == 'T') && (strcmp(flag, "TRUNC") == 0)) {
	    mode |= O_TRUNC;
	} else if ((c == 'B') && (strcmp(flag, "BINARY") == 0)) {
	    *binaryPtr = 1;
	} else {

	    if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"invalid access mode \"%s\": must be RDONLY, WRONLY, "
			"RDWR, APPEND, BINARY, CREAT, EXCL, NOCTTY, NONBLOCK,"
			" or TRUNC", flag));
	    }
	    ckfree(modeArgv);
	    return -1;
	}
    }

    ckfree(modeArgv);

    if (!gotRW) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "access mode must include either RDONLY, WRONLY, or RDWR",
		    -1));
	}
	return -1;
    }
    return mode;
}

/*

    if (Tcl_FSGetNormalizedPath(interp, pathPtr) == NULL) {
	return result;
    }

    if (Tcl_FSStat(pathPtr, &statBuf) == -1) {
	Tcl_SetErrno(errno);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	return result;
    }
    chan = Tcl_FSOpenFileChannel(interp, pathPtr, "r", 0644);
    if (chan == NULL) {
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	return result;
    }

    /*
     * The eofchar is \32 (^Z). This is the usual on Windows, but we effect
     * this cross-platform to allow for scripted documents. [Bug: 2040]
     */

	    Tcl_Close(interp,chan);
	    return result;
	}
    }

    objPtr = Tcl_NewObj();
    Tcl_IncrRefCount(objPtr);

    /*
     * Try to read first character of stream, so we can check for utf-8 BOM to
     * be handled especially.
     */

    if (Tcl_ReadChars(chan, objPtr, 1, 0) < 0) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	goto end;
    }
    string = Tcl_GetString(objPtr);

    /*
     * If first character is not a BOM, append the remaining characters,
     * otherwise replace them. [Bug 3466099]
     */

    if (Tcl_ReadChars(chan, objPtr, -1,
	    memcmp(string, "\xef\xbb\xbf", 3)) < 0) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	goto end;
    }

    if (Tcl_Close(interp, chan) != TCL_OK) {
	goto end;
    }

    const char *encodingName)	/* If non-NULL, then use this encoding for the
				 * file. NULL means use the system encoding. */
{
    Tcl_StatBuf statBuf;
    Tcl_Obj *oldScriptFile, *objPtr;
    Interp *iPtr;
    Tcl_Channel chan;
    const char *string;

    if (Tcl_FSGetNormalizedPath(interp, pathPtr) == NULL) {
	return TCL_ERROR;
    }

    if (Tcl_FSStat(pathPtr, &statBuf) == -1) {
	Tcl_SetErrno(errno);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	return TCL_ERROR;
    }
    chan = Tcl_FSOpenFileChannel(interp, pathPtr, "r", 0644);
    if (chan == NULL) {
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	return TCL_ERROR;
    }

    /*
     * The eofchar is \32 (^Z). This is the usual on Windows, but we effect
     * this cross-platform to allow for scripted documents. [Bug: 2040]
     */

	    Tcl_Close(interp,chan);
	    return TCL_ERROR;
	}
    }

    objPtr = Tcl_NewObj();
    Tcl_IncrRefCount(objPtr);

    /*
     * Try to read first character of stream, so we can check for utf-8 BOM to
     * be handled especially.
     */

    if (Tcl_ReadChars(chan, objPtr, 1, 0) < 0) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	Tcl_DecrRefCount(objPtr);
	return TCL_ERROR;
    }
    string = Tcl_GetString(objPtr);

    /*
     * If first character is not a BOM, append the remaining characters,
     * otherwise replace them. [Bug 3466099]
     */

    if (Tcl_ReadChars(chan, objPtr, -1,
	    memcmp(string, "\xef\xbb\xbf", 3)) < 0) {
	Tcl_Close(interp, chan);
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't read file \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	Tcl_DecrRefCount(objPtr);
	return TCL_ERROR;
    }

    if (Tcl_Close(interp, chan) != TCL_OK) {
	Tcl_DecrRefCount(objPtr);
	return TCL_ERROR;

	/*
	 * Apply appropriate flags parsed out above.
	 */

	if (seekFlag && Tcl_Seek(retVal, (Tcl_WideInt) 0, SEEK_END)
		< (Tcl_WideInt) 0) {
	    if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"could not seek to end of file while opening \"%s\": %s",
			Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	    }
	    Tcl_Close(NULL, retVal);
	    return NULL;
	}
	if (binary) {
	    Tcl_SetChannelOption(interp, retVal, "-translation", "binary");
	}
	return retVal;
    }

    /*
     * File doesn't belong to any filesystem that can open it.
     */

    Tcl_SetErrno(ENOENT);
    if (interp != NULL) {
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't open \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
    }
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *

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

Tcl_Obj *
Tcl_FSGetCwd(
    Tcl_Interp *interp)
{
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);

    if (TclFSCwdPointerEquals(NULL)) {
	FilesystemRecord *fsRecPtr;
	Tcl_Obj *retVal = NULL;

	/*
	 * We've never been called before, try to find a cwd. Call each of the
	 * "Tcl_GetCwd" function in succession. A non-NULL return value
	 * indicates the particular function has succeeded.
	 */

	fsRecPtr = FsGetFirstFilesystem();
	Claim();
	for (; (retVal == NULL) && (fsRecPtr != NULL);
		fsRecPtr = fsRecPtr->nextPtr) {
	    ClientData retCd;
	    TclFSGetCwdProc2 *proc2;
	    if (fsRecPtr->fsPtr->getCwdProc == NULL) {
		continue;
	    }

		/*
		 * Looks like a new current directory.
		 */

		retVal = fsRecPtr->fsPtr->internalToNormalizedProc(retCd);
		Tcl_IncrRefCount(retVal);
		norm = TclFSNormalizeAbsolutePath(interp,retVal);
		if (norm != NULL) {
		    /*
		     * We found a cwd, which is now in our global storage. We
		     * must make a copy. Norm already has a refCount of 1.
		     *
		     * Threading issue: note that multiple threads at system
		     * startup could in principle call this function
		     * simultaneously. They will therefore each set the
		     * cwdPathPtr independently. That behaviour is a bit
		     * peculiar, but should be fine. Once we have a cwd, we'll
		     * always be in the 'else' branch below which is simpler.
		     */

		    FsUpdateCwd(norm, retCd);
		    Tcl_DecrRefCount(norm);
		} else {
		    fsRecPtr->fsPtr->freeInternalRepProc(retCd);
		}
		Tcl_DecrRefCount(retVal);
		retVal = NULL;
		Disclaim();
		goto cdDidNotChange;
	    } else if (interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"error getting working directory name: %s",
			Tcl_PosixError(interp)));
	    }
	}
	Disclaim();

	/*
	 * Now the 'cwd' may NOT be normalized, at least on some platforms.
	 * For the sake of efficiency, we want a completely normalized cwd at
	 * all times.
	 *
	 * Finally, if retVal is NULL, we do not have a cwd, which could be
	 * problematic.
	 */

	if (retVal != NULL) {
	    Tcl_Obj *norm = TclFSNormalizeAbsolutePath(interp, retVal);

	    if (norm != NULL) {
		/*
		 * We found a cwd, which is now in our global storage. We must
		 * make a copy. Norm already has a refCount of 1.
		 *
		 * Threading issue: note that multiple threads at system

	     * New API.
	     */

	    TclFSGetCwdProc2 *proc2 = (TclFSGetCwdProc2 *) fsPtr->getCwdProc;

	    retCd = proc2(tsdPtr->cwdClientData);
	    if (retCd == NULL && interp != NULL) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"error getting working directory name: %s",
			Tcl_PosixError(interp)));
	    }

	    if (retCd == tsdPtr->cwdClientData) {
		goto cdDidNotChange;
	    }

	    /*

	    goto cdDidNotChange;
	}

	/*
	 * Normalize the path.
	 */

	norm = TclFSNormalizeAbsolutePath(interp, retVal);

	/*
	 * Check whether cwd has changed from the value previously stored in
	 * cwdPathPtr. Really 'norm' shouldn't be NULL, but we are careful.
	 */

	if (norm == NULL) {

	     * again here. On Unix it might actually be true that we always
	     * have the correct form in the native rep in which case we could
	     * simply use:
	     *		cd = Tcl_FSGetNativePath(pathPtr);
	     * instead. This should be examined by someone on Unix.
	     */

	    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&fsDataKey);
	    ClientData cd;
	    ClientData oldcd = tsdPtr->cwdClientData;

	    /*
	     * Assumption we are using a filesystem version 2.
	     */

int
Tcl_LoadFile(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Obj *pathPtr,		/* Name of the file containing the desired
				 * code. */
    const char *const symbols[],/* Names of functions to look up in the file's
				 * symbol table. */
    int flags,			/* Flags */
    void *procVPtrs,		/* Where to return the addresses corresponding
				 * to symbols[]. */
    Tcl_LoadHandle *handlePtr)	/* Filled with token for shared library
				 * information which can be used in
				 * TclpFindSymbol. */
{
    void **procPtrs = (void **) procVPtrs;

    if (fsPtr == NULL) {
	Tcl_SetErrno(ENOENT);
	return TCL_ERROR;
    }

    if (fsPtr->loadFileProc != NULL) {
	int retVal = ((Tcl_FSLoadFileProc2 *)(fsPtr->loadFileProc))
		(interp, pathPtr, handlePtr, &unloadProcPtr, flags);

	if (retVal == TCL_OK) {
	    if (*handlePtr == NULL) {
		return TCL_ERROR;
	    }
	    Tcl_ResetResult(interp);
	    goto resolveSymbols;

     * The filesystem doesn't support 'load', so we fall back on the following
     * technique:
     *
     * First check if it is readable -- and exists!
     */

    if (Tcl_FSAccess(pathPtr, R_OK) != 0) {
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"couldn't load library \"%s\": %s",
		Tcl_GetString(pathPtr), Tcl_PosixError(interp)));
	return TCL_ERROR;
    }

#ifdef TCL_LOAD_FROM_MEMORY
    /*
     * The platform supports loading code from memory, so ask for a buffer of
     * the appropriate size, read the file into it and load the code from the

	if (!buffer) {
	    Tcl_Close(interp, data);
	    goto mustCopyToTempAnyway;
	}
	ret = Tcl_Read(data, buffer, size);
	Tcl_Close(interp, data);
	ret = TclpLoadMemory(interp, buffer, size, ret, handlePtr,
		&unloadProcPtr, flags);
	if (ret == TCL_OK && *handlePtr != NULL) {
	    goto resolveSymbols;
	}
    }

  mustCopyToTempAnyway:
    Tcl_ResetResult(interp);
#endif /* TCL_LOAD_FROM_MEMORY */

    /*
     * Get a temporary filename to use, first to copy the file into, and then
     * to load.
     */

    copyToPtr = TclpTempFileNameForLibrary(interp, pathPtr);
    Tcl_IncrRefCount(copyToPtr);

    copyFsPtr = Tcl_FSGetFileSystemForPath(copyToPtr);
    if ((copyFsPtr == NULL) || (copyFsPtr == fsPtr)) {
	/*
	 * We already know we can't use Tcl_FSLoadFile from this filesystem,
	 * and we must avoid a possible infinite loop. Try to delete the file
	 * we probably created, and then exit.
	 */

	Tcl_FSDeleteFile(copyToPtr);
	Tcl_DecrRefCount(copyToPtr);
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"couldn't load from current filesystem", -1));

	return TCL_ERROR;
    }

    if (TclCrossFilesystemCopy(interp, pathPtr, copyToPtr) != TCL_OK) {
	/*
	 * Cross-platform copy failed.
	 */

    /*
     * We need to reset the result now, because the cross-filesystem copy may
     * have stored the number of bytes in the result.
     */

    Tcl_ResetResult(interp);

    retVal = Tcl_LoadFile(interp, copyToPtr, symbols, flags, procPtrs,
	    &newLoadHandle);
    if (retVal != TCL_OK) {
	/*
	 * The file didn't load successfully.
	 */

	Tcl_FSDeleteFile(copyToPtr);

	Tcl_DecrRefCount(tvdlPtr->divertedFile);
    }

    ckfree(tvdlPtr);
    ckfree(loadHandle);
}













































/*
 *----------------------------------------------------------------------
 *
 * Tcl_FindSymbol --
 *
 *	Find a symbol in a loaded library

     * Call each of the "listVolumes" function in succession. A non-NULL
     * return value indicates the particular function has succeeded. We call
     * all the functions registered, since we want a list of all drives from
     * all filesystems.
     */

    fsRecPtr = FsGetFirstFilesystem();
    Claim();
    while (fsRecPtr != NULL) {
	if (fsRecPtr->fsPtr->listVolumesProc != NULL) {
	    Tcl_Obj *thisFsVolumes = fsRecPtr->fsPtr->listVolumesProc();

	    if (thisFsVolumes != NULL) {
		Tcl_ListObjAppendList(NULL, resultPtr, thisFsVolumes);
		Tcl_DecrRefCount(thisFsVolumes);
	    }
	}
	fsRecPtr = fsRecPtr->nextPtr;
    }
    Disclaim();

    return resultPtr;
}

/*
 *---------------------------------------------------------------------------
 *

     * Call each of the "matchInDirectory" functions in succession, with the
     * specific type information 'mountsOnly'. A non-NULL return value
     * indicates the particular function has succeeded. We call all the
     * functions registered, since we want a list from each filesystems.
     */

    fsRecPtr = FsGetFirstFilesystem();
    Claim();
    while (fsRecPtr != NULL) {
	if (fsRecPtr->fsPtr != &tclNativeFilesystem &&
		fsRecPtr->fsPtr->matchInDirectoryProc != NULL) {
	    if (resultPtr == NULL) {
		resultPtr = Tcl_NewObj();
	    }
	    fsRecPtr->fsPtr->matchInDirectoryProc(NULL, resultPtr, pathPtr,
		    pattern, &mountsOnly);
	}
	fsRecPtr = fsRecPtr->nextPtr;
    }
    Disclaim();

    return resultPtr;
}

/*
 *---------------------------------------------------------------------------
 *

     */

    if (lenPtr != NULL) {
	TclListObjLength(NULL, result, lenPtr);
    }
    return result;
}

























/*
 *----------------------------------------------------------------------
 *
 * TclGetPathType --
 *
 *	Helper function used by FSGetPathType.
 *

    /*
     * Call each of the "listVolumes" function in succession, checking whether
     * the given path is an absolute path on any of the volumes returned (this
     * is done by checking whether the path's prefix matches).
     */

    fsRecPtr = FsGetFirstFilesystem();
    Claim();
    while (fsRecPtr != NULL) {
	/*
	 * We want to skip the native filesystem in this loop because
	 * otherwise we won't necessarily pass all the Tcl testsuite - this is
	 * because some of the tests artificially change the current platform
	 * (between win, unix) but the list of volumes we get by calling
	 * fsRecPtr->fsPtr->listVolumesProc will reflect the current (real)

		    break;
		}
	    }
	}
	fsRecPtr = fsRecPtr->nextPtr;
    }
    Disclaim();
    return type;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tcl_FSRenameFile --

     * Check if the filesystem has changed in some way since this object's
     * internal representation was calculated. Before doing that, assure we
     * have the most up-to-date copy of the master filesystem. This is
     * accomplished by the FsGetFirstFilesystem() call.
     */

    fsRecPtr = FsGetFirstFilesystem();
    Claim();

    if (TclFSEnsureEpochOk(pathPtr, &retVal) != TCL_OK) {
	Disclaim();
	return NULL;
    } else if (retVal != NULL) {
	/* TODO: Can this happen? */
	Disclaim();
	return retVal;
    }

    /*
     * Call each of the "pathInFilesystem" functions in succession. A
     * non-return value of -1 indicates the particular function has succeeded.
     */

	if (fsRecPtr->fsPtr->pathInFilesystemProc(pathPtr, &clientData)!=-1) {
	    /*
	     * We assume the type of pathPtr hasn't been changed by the above
	     * call to the pathInFilesystemProc.
	     */

	    TclFSSetPathDetails(pathPtr, fsRecPtr->fsPtr, clientData);
	    Disclaim();
	    return fsRecPtr->fsPtr;
	}
    }
    Disclaim();

    return NULL;
}

/*
 *---------------------------------------------------------------------------
 *