ObjFW  Artifact [7e257a10c2]

Artifact 7e257a10c2df655c1a4adcfd069e43b7a3245cd4220d540095b72e9c59139909:

• File src/OFFileManager.m — part of check-in [f3c452dfef] at 2015-08-22 10:57:14 on branch trunk — Move file management to its own class

  This makes it possible to add support for delegates for file management
  operations and on top makes it easier to add support for file management
  operations on URLs. (user: js, size: 21377) [annotate] [blame] [check-ins using]

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015
 *   Jonathan Schleifer <js@webkeks.org>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *
 * Alternatively, it may be distributed under the terms of the GNU General
 * Public License, either version 2 or 3, which can be found in the file
 * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
 * file.
 */

#include "config.h"

#include <errno.h>

#include <dirent.h>
#include <unistd.h>

#ifdef HAVE_PWD_H
# include <pwd.h>
#endif
#ifdef HAVE_GRP_H
# include <grp.h>
#endif

#import "OFFileManager.h"
#import "OFFile.h"
#import "OFString.h"
#import "OFArray.h"
#import "OFDate.h"
#import "OFSystemInfo.h"

#ifdef OF_HAVE_THREADS
# import "threading.h"
#endif

#import "OFChangeCurrentDirectoryPathFailedException.h"
#import "OFChangeOwnerFailedException.h"
#import "OFChangePermissionsFailedException.h"
#import "OFCopyItemFailedException.h"
#import "OFCreateDirectoryFailedException.h"
#import "OFCreateSymbolicLinkFailedException.h"
#import "OFInitializationFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFLinkFailedException.h"
#import "OFLockFailedException.h"
#import "OFMoveItemFailedException.h"
#import "OFOpenItemFailedException.h"
#import "OFOutOfMemoryException.h"
#import "OFReadFailedException.h"
#import "OFRemoveItemFailedException.h"
#import "OFStatItemFailedException.h"
#import "OFUnlockFailedException.h"

#ifdef _WIN32
# include <windows.h>
# include <direct.h>
#endif

#ifndef S_IRGRP
# define S_IRGRP 0
#endif
#ifndef S_IROTH
# define S_IROTH 0
#endif
#ifndef S_IWGRP
# define S_IWGRP 0
#endif
#ifndef S_IWOTH
# define S_IWOTH 0
#endif

#define DEFAULT_MODE S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH
#define DIR_MODE DEFAULT_MODE | S_IXUSR | S_IXGRP | S_IXOTH

static OFFileManager *defaultManager;

#if defined(OF_HAVE_CHOWN) && defined(OF_HAVE_THREADS)
static of_mutex_t chownMutex;
#endif
#if !defined(HAVE_READDIR_R) && !defined(_WIN32) && defined(OF_HAVE_THREADS)
static of_mutex_t readdirMutex;
#endif

int
of_stat(OFString *path, of_stat_t *buffer)
{
#if defined(_WIN32)
	return _wstat64([path UTF16String], buffer);
#elif defined(OF_HAVE_OFF64_T)
	return stat64([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
#else
	return stat([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
#endif
}

int
of_lstat(OFString *path, of_stat_t *buffer)
{
#if defined(_WIN32)
	return _wstat64([path UTF16String], buffer);
#elif defined(HAVE_LSTAT)
# ifdef OF_HAVE_OFF64_T
	return lstat64([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
# else
	return lstat([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
# endif
#else
# ifdef OF_HAVE_OFF64_T
	return stat64([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
# else
	return stat([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]], buffer);
# endif
#endif
}

@implementation OFFileManager
+ (void)initialize
{
	if (self != [OFFileManager class])
		return;

	/*
	 * Make sure OFFile is initialized.
	 * On some systems, this is needed to initialize the file system driver.
	 */
	[OFFile class];

#if defined(OF_HAVE_CHOWN) && defined(OF_HAVE_THREADS)
	if (!of_mutex_new(&chownMutex))
		@throw [OFInitializationFailedException
		    exceptionWithClass: self];
#endif

#if !defined(HAVE_READDIR_R) && !defined(_WIN32) && defined(OF_HAVE_THREADS)
	if (!of_mutex_new(&readdirMutex))
		@throw [OFInitializationFailedException
		    exceptionWithClass: self];
#endif

	defaultManager = [[OFFileManager alloc] init];
}

+ (OFFileManager*)defaultManager
{
	return defaultManager;
}

- (OFString*)currentDirectoryPath
{
	OFString *ret;
#ifndef _WIN32
	char *buffer = getcwd(NULL, 0);
#else
	wchar_t *buffer = _wgetcwd(NULL, 0);
#endif

	@try {
#ifndef _WIN32
		ret = [OFString
		    stringWithCString: buffer
			     encoding: [OFSystemInfo native8BitEncoding]];
#else
		ret = [OFString stringWithUTF16String: buffer];
#endif
	} @finally {
		free(buffer);
	}

	return ret;
}

- (bool)fileExistsAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) == -1)
		return false;

	if (S_ISREG(s.st_mode))
		return true;

	return false;
}

- (bool)directoryExistsAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) == -1)
		return false;

	if (S_ISDIR(s.st_mode))
		return true;

	return false;
}

#ifdef OF_HAVE_SYMLINK
- (bool)symbolicLinkExistsAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_lstat(path, &s) == -1)
		return false;

	if (S_ISLNK(s.st_mode))
		return true;

	return false;
}
#endif

- (void)createDirectoryAtPath: (OFString*)path
{
	if (path == nil)
		@throw [OFInvalidArgumentException exception];

#ifndef _WIN32
	if (mkdir([path cStringWithEncoding: [OFSystemInfo native8BitEncoding]],
	    DIR_MODE) != 0)
#else
	if (_wmkdir([path UTF16String]) != 0)
#endif
		@throw [OFCreateDirectoryFailedException
		    exceptionWithPath: path
				errNo: errno];
}

- (void)createDirectoryAtPath: (OFString*)path
		createParents: (bool)createParents
{
	void *pool;
	OFArray *pathComponents;
	OFString *currentPath = nil, *component;
	OFEnumerator *enumerator;

	if (!createParents) {
		[self createDirectoryAtPath: path];
		return;
	}

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();

	pathComponents = [path pathComponents];
	enumerator = [pathComponents objectEnumerator];
	while ((component = [enumerator nextObject]) != nil) {
		void *pool2 = objc_autoreleasePoolPush();

		if (currentPath != nil)
			currentPath = [currentPath
			    stringByAppendingPathComponent: component];
		else
			currentPath = component;

		if ([currentPath length] > 0 &&
		    ![self directoryExistsAtPath: currentPath])
			[self createDirectoryAtPath: currentPath];

		[currentPath retain];

		objc_autoreleasePoolPop(pool2);

		[currentPath autorelease];
	}

	objc_autoreleasePoolPop(pool);
}

- (OFArray*)contentsOfDirectoryAtPath: (OFString*)path
{
	OFMutableArray *files;
#ifndef _WIN32
	of_string_encoding_t encoding;
#endif

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	files = [OFMutableArray array];

#ifndef _WIN32
	DIR *dir;

	encoding = [OFSystemInfo native8BitEncoding];

	if ((dir = opendir([path cStringWithEncoding: encoding])) == NULL)
		@throw [OFOpenItemFailedException exceptionWithPath: path
							      errNo: errno];

# if !defined(HAVE_READDIR_R) && defined(OF_HAVE_THREADS)
	if (!of_mutex_lock(&readdirMutex))
		@throw [OFLockFailedException exception];
# endif

	@try {
		for (;;) {
			struct dirent *dirent;
# ifdef HAVE_READDIR_R
			struct dirent buffer;
# endif
			void *pool;
			OFString *file;

# ifdef HAVE_READDIR_R
			if (readdir_r(dir, &buffer, &dirent) != 0)
				@throw [OFReadFailedException
				    exceptionWithObject: self
					requestedLength: 0
						  errNo: errno];

			if (dirent == NULL)
				break;
# else
			if ((dirent = readdir(dir)) == NULL) {
				if (errno == 0)
					break;
				else
					@throw [OFReadFailedException
					    exceptionWithObject: self
						requestedLength: 0
							  errNo: errno];
			}
# endif

			if (strcmp(dirent->d_name, ".") == 0 ||
			    strcmp(dirent->d_name, "..") == 0)
				continue;

			pool = objc_autoreleasePoolPush();

			file = [OFString stringWithCString: dirent->d_name
						  encoding: encoding];
			[files addObject: file];

			objc_autoreleasePoolPop(pool);
		}
	} @finally {
		closedir(dir);
# if !defined(HAVE_READDIR_R) && defined(OF_HAVE_THREADS)
		if (!of_mutex_unlock(&readdirMutex))
			@throw [OFUnlockFailedException exception];
# endif
	}
#else
	void *pool = objc_autoreleasePoolPush();
	HANDLE handle;
	WIN32_FIND_DATAW fd;

	path = [path stringByAppendingString: @"\\*"];

	if ((handle = FindFirstFileW([path UTF16String],
	    &fd)) == INVALID_HANDLE_VALUE) {
		int errNo = 0;

		if (GetLastError() == ERROR_FILE_NOT_FOUND)
			errNo = ENOENT;

		@throw [OFOpenItemFailedException exceptionWithPath: path
							      errNo: errNo];
	}

	@try {
		do {
			void *pool2 = objc_autoreleasePoolPush();
			OFString *file;

			if (!wcscmp(fd.cFileName, L".") ||
			    !wcscmp(fd.cFileName, L".."))
				continue;

			file = [OFString stringWithUTF16String: fd.cFileName];
			[files addObject: file];

			objc_autoreleasePoolPop(pool2);
		} while (FindNextFileW(handle, &fd));

		if (GetLastError() != ERROR_NO_MORE_FILES)
			@throw [OFReadFailedException exceptionWithObject: self
							  requestedLength: 0];
	} @finally {
		FindClose(handle);
	}

	objc_autoreleasePoolPop(pool);
#endif

	[files makeImmutable];

	return files;
}

- (void)changeCurrentDirectoryPath: (OFString*)path
{
	if (path == nil)
		@throw [OFInvalidArgumentException exception];

#ifndef _WIN32
	if (chdir([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]]) != 0)
#else
	if (_wchdir([path UTF16String]) != 0)
#endif
		@throw [OFChangeCurrentDirectoryPathFailedException
		    exceptionWithPath: path
				errNo: errno];
}

- (of_offset_t)sizeOfFileAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) != 0)
		@throw [OFStatItemFailedException exceptionWithPath: path
							      errNo: errno];

	return s.st_size;
}

- (OFDate*)accessTimeOfItemAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) != 0)
		@throw [OFStatItemFailedException exceptionWithPath: path
							      errNo: errno];

	/* FIXME: We could be more precise on some OSes */
	return [OFDate dateWithTimeIntervalSince1970: s.st_atime];
}

- (OFDate*)modificationTimeOfItemAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) != 0)
		@throw [OFStatItemFailedException exceptionWithPath: path
							      errNo: errno];

	/* FIXME: We could be more precise on some OSes */
	return [OFDate dateWithTimeIntervalSince1970: s.st_mtime];
}

- (OFDate*)statusChangeTimeOfItemAtPath: (OFString*)path
{
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	if (of_stat(path, &s) != 0)
		@throw [OFStatItemFailedException exceptionWithPath: path
							      errNo: errno];

	/* FIXME: We could be more precise on some OSes */
	return [OFDate dateWithTimeIntervalSince1970: s.st_ctime];
}

#ifdef OF_HAVE_CHMOD
- (void)changePermissionsOfItemAtPath: (OFString*)path
			  permissions: (mode_t)permissions
{
	if (path == nil)
		@throw [OFInvalidArgumentException exception];

# ifndef _WIN32
	if (chmod([path cStringWithEncoding: [OFSystemInfo native8BitEncoding]],
	    permissions) != 0)
# else
	if (_wchmod([path UTF16String], permissions) != 0)
# endif
		@throw [OFChangePermissionsFailedException
		    exceptionWithPath: path
			  permissions: permissions
				errNo: errno];
}
#endif

#ifdef OF_HAVE_CHOWN
- (void)changeOwnerOfItemAtPath: (OFString*)path
			  owner: (OFString*)owner
			  group: (OFString*)group
{
	uid_t uid = -1;
	gid_t gid = -1;
	of_string_encoding_t encoding;

	if (path == nil || (owner == nil && group == nil))
		@throw [OFInvalidArgumentException exception];

	encoding = [OFSystemInfo native8BitEncoding];

# ifdef OF_HAVE_THREADS
	if (!of_mutex_lock(&chownMutex))
		@throw [OFLockFailedException exception];

	@try {
# endif
		if (owner != nil) {
			struct passwd *passwd;

			if ((passwd = getpwnam([owner
			    cStringWithEncoding: encoding])) == NULL)
				@throw [OFChangeOwnerFailedException
				    exceptionWithPath: path
						owner: owner
						group: group
						errNo: errno];

			uid = passwd->pw_uid;
		}

		if (group != nil) {
			struct group *group_;

			if ((group_ = getgrnam([group
			    cStringWithEncoding: encoding])) == NULL)
				@throw [OFChangeOwnerFailedException
				    exceptionWithPath: path
						owner: owner
						group: group
						errNo: errno];

			gid = group_->gr_gid;
		}
# ifdef OF_HAVE_THREADS
	} @finally {
		if (!of_mutex_unlock(&chownMutex))
			@throw [OFUnlockFailedException exception];
	}
# endif

	if (chown([path cStringWithEncoding: encoding], uid, gid) != 0)
		@throw [OFChangeOwnerFailedException exceptionWithPath: path
								 owner: owner
								 group: group
								 errNo: errno];
}
#endif

- (void)copyItemAtPath: (OFString*)source
		toPath: (OFString*)destination
{
	void *pool;
	of_stat_t s;

	if (source == nil || destination == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();

	if (of_lstat(destination, &s) == 0)
		@throw [OFCopyItemFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: EEXIST];

	if (of_lstat(source, &s) != 0)
		@throw [OFCopyItemFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: errno];

	if (S_ISDIR(s.st_mode)) {
		OFArray *contents;
		OFEnumerator *enumerator;
		OFString *item;

		@try {
			[self createDirectoryAtPath: destination];
#ifdef OF_HAVE_CHMOD
			[self changePermissionsOfItemAtPath: destination
						permissions: s.st_mode];
#endif

			contents = [self contentsOfDirectoryAtPath: source];
		} @catch (id e) {
			/*
			 * Only convert exceptions to OFCopyItemFailedException
			 * that have an errNo property. This covers all I/O
			 * related exceptions from the operations used to copy
			 * an item, all others should be left as is.
			 */
			if ([e respondsToSelector: @selector(errNo)])
				@throw [OFCopyItemFailedException
				    exceptionWithSourcePath: source
					    destinationPath: destination
						      errNo: [e errNo]];

			@throw e;
		}

		enumerator = [contents objectEnumerator];
		while ((item = [enumerator nextObject]) != nil) {
			void *pool2 = objc_autoreleasePoolPush();
			OFString *sourcePath, *destinationPath;

			sourcePath =
			    [source stringByAppendingPathComponent: item];
			destinationPath =
			    [destination stringByAppendingPathComponent: item];

			[self copyItemAtPath: sourcePath
				      toPath: destinationPath];

			objc_autoreleasePoolPop(pool2);
		}
	} else if (S_ISREG(s.st_mode)) {
		size_t pageSize = [OFSystemInfo pageSize];
		OFFile *sourceFile = nil;
		OFFile *destinationFile = nil;
		char *buffer;

		if ((buffer = malloc(pageSize)) == NULL)
			@throw [OFOutOfMemoryException
			    exceptionWithRequestedSize: pageSize];

		@try {
			sourceFile = [OFFile fileWithPath: source
						     mode: @"rb"];
			destinationFile = [OFFile fileWithPath: destination
							  mode: @"wb"];

			while (![sourceFile isAtEndOfStream]) {
				size_t length;

				length = [sourceFile readIntoBuffer: buffer
							     length: pageSize];
				[destinationFile writeBuffer: buffer
						      length: length];
			}

#ifdef OF_HAVE_CHMOD
			[self changePermissionsOfItemAtPath: destination
						permissions: s.st_mode];
#endif
		} @catch (id e) {
			/*
			 * Only convert exceptions to OFCopyItemFailedException
			 * that have an errNo property. This covers all I/O
			 * related exceptions from the operations used to copy
			 * an item, all others should be left as is.
			 */
			if ([e respondsToSelector: @selector(errNo)])
				@throw [OFCopyItemFailedException
				    exceptionWithSourcePath: source
					    destinationPath: destination
						      errNo: [e errNo]];

			@throw e;
		} @finally {
			[sourceFile close];
			[destinationFile close];
			free(buffer);
		}
#ifdef OF_HAVE_SYMLINK
	} else if (S_ISLNK(s.st_mode)) {
		@try {
			source = [self destinationOfSymbolicLinkAtPath: source];

			[self createSymbolicLinkAtPath: destination
				   withDestinationPath: source];
		} @catch (id e) {
			/*
			 * Only convert exceptions to OFCopyItemFailedException
			 * that have an errNo property. This covers all I/O
			 * related exceptions from the operations used to copy
			 * an item, all others should be left as is.
			 */
			if ([e respondsToSelector: @selector(errNo)])
				@throw [OFCopyItemFailedException
				    exceptionWithSourcePath: source
					    destinationPath: destination
						      errNo: [e errNo]];

			@throw e;
		}
#endif
	} else
		@throw [OFCopyItemFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: ENOTSUP];

	objc_autoreleasePoolPop(pool);
}

- (void)moveItemAtPath: (OFString*)source
		toPath: (OFString*)destination
{
	void *pool;
	of_stat_t s;
#ifndef _WIN32
	of_string_encoding_t encoding;
#endif

	if (source == nil || destination == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();

	if (of_lstat(destination, &s) == 0)
		@throw [OFCopyItemFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: EEXIST];

#ifndef _WIN32
	encoding = [OFSystemInfo native8BitEncoding];

	if (rename([source cStringWithEncoding: encoding],
	    [destination cStringWithEncoding: encoding]) != 0) {
#else
	if (_wrename([source UTF16String], [destination UTF16String]) != 0) {
#endif
		if (errno != EXDEV)
			@throw [OFMoveItemFailedException
			    exceptionWithSourcePath: source
				    destinationPath: destination
					      errNo: errno];

		@try {
			[self copyItemAtPath: source
				      toPath: destination];
		} @catch (OFCopyItemFailedException *e) {
			[self removeItemAtPath: destination];

			@throw [OFMoveItemFailedException
			    exceptionWithSourcePath: source
				    destinationPath: destination
					      errNo: [e errNo]];
		}

		@try {
			[self removeItemAtPath: source];
		} @catch (OFRemoveItemFailedException *e) {
			@throw [OFMoveItemFailedException
			    exceptionWithSourcePath: source
				    destinationPath: destination
					      errNo: [e errNo]];
		}
	}

	objc_autoreleasePoolPop(pool);
}

- (void)removeItemAtPath: (OFString*)path
{
	void *pool;
	of_stat_t s;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();

	if (of_lstat(path, &s) != 0)
		@throw [OFRemoveItemFailedException exceptionWithPath: path
								errNo: errno];

	if (S_ISDIR(s.st_mode)) {
		OFArray *contents;
		OFEnumerator *enumerator;
		OFString *item;

		@try {
			contents = [self contentsOfDirectoryAtPath: path];
		} @catch (id e) {
			/*
			 * Only convert exceptions to
			 * OFRemoveItemFailedException that have an errNo
			 * property. This covers all I/O related exceptions
			 * from the operations used to remove an item, all
			 * others should be left as is.
			 */
			if ([e respondsToSelector: @selector(errNo)])
				@throw [OFRemoveItemFailedException
				    exceptionWithPath: path
						errNo: [e errNo]];

			@throw e;
		}

		enumerator = [contents objectEnumerator];
		while ((item = [enumerator nextObject]) != nil) {
			void *pool2 = objc_autoreleasePoolPush();

			[self removeItemAtPath:
			    [path stringByAppendingPathComponent: item]];

			objc_autoreleasePoolPop(pool2);
		}
	}

#ifndef _WIN32
	if (remove([path cStringWithEncoding:
	    [OFSystemInfo native8BitEncoding]]) != 0)
#else
	if (_wremove([path UTF16String]) != 0)
#endif
		@throw [OFRemoveItemFailedException exceptionWithPath: path
								errNo: errno];

	objc_autoreleasePoolPop(pool);
}

#ifdef OF_HAVE_LINK
- (void)linkItemAtPath: (OFString*)source
		toPath: (OFString*)destination
{
	void *pool;
	of_string_encoding_t encoding;

	if (source == nil || destination == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();
	encoding = [OFSystemInfo native8BitEncoding];

	if (link([source cStringWithEncoding: encoding],
	    [destination cStringWithEncoding: encoding]) != 0)
		@throw [OFLinkFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: errno];

	objc_autoreleasePoolPop(pool);
}
#endif

#ifdef OF_HAVE_SYMLINK
- (void)createSymbolicLinkAtPath: (OFString*)destination
	     withDestinationPath: (OFString*)source
{
	void *pool;
	of_string_encoding_t encoding;

	if (source == nil || destination == nil)
		@throw [OFInvalidArgumentException exception];

	pool = objc_autoreleasePoolPush();
	encoding = [OFSystemInfo native8BitEncoding];

	if (symlink([source cStringWithEncoding: encoding],
	    [destination cStringWithEncoding: encoding]) != 0)
		@throw [OFCreateSymbolicLinkFailedException
		    exceptionWithSourcePath: source
			    destinationPath: destination
				      errNo: errno];

	objc_autoreleasePoolPop(pool);
}

- (OFString*)destinationOfSymbolicLinkAtPath: (OFString*)path
{
	char destination[PATH_MAX];
	ssize_t length;
	of_string_encoding_t encoding;

	if (path == nil)
		@throw [OFInvalidArgumentException exception];

	encoding = [OFSystemInfo native8BitEncoding];
	length = readlink([path cStringWithEncoding: encoding],
	    destination, PATH_MAX);

	if (length < 0)
		@throw [OFStatItemFailedException exceptionWithPath: path
							      errNo: errno];

	return [OFString stringWithCString: destination
				  encoding: encoding
				    length: length];
}
#endif
@end