plain_io.c - platform/external/mtools - Git at Google

 /*  Copyright 1995-2007,2009,2011 Alain Knaff.
  *  This file is part of mtools.
  *
  *  Mtools is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation, either version 3 of the License, or
  *  (at your option) any later version.
  *
  *  Mtools is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with Mtools.  If not, see <http://www.gnu.org/licenses/>.
  *
  * Io to a plain file or device
  *
  * written by:
  *
  * Alain L. Knaff
  * alain@knaff.lu
  *
  */

 #include "sysincludes.h"
 #include "stream.h"
 #include "mtools.h"
 #include "msdos.h"
 #include "open_image.h"
 #include "devices.h"
 #include "plain_io.h"
 #include "llong.h"

 #ifdef HAVE_LINUX_FS_H
 # include <linux/fs.h>
 #endif

 typedef struct SimpleFile_t {
     struct Stream_t head;

     struct MT_STAT statbuf;
     int fd;
     mt_off_t lastwhere;
     int seekable;
     int privileged;
 #ifdef OS_hpux
     int size_limited;
 #endif
 } SimpleFile_t;


 #include "lockdev.h"

 typedef ssize_t (*iofn) (int, void *, size_t);

 static ssize_t file_io(SimpleFile_t *This, char *buf,
 		       mt_off_t where, size_t len,
 		       iofn io)
 {
 	ssize_t ret;

 	if (This->seekable && where != This->lastwhere ){
 		if(mt_lseek( This->fd, where, SEEK_SET) < 0 ){
 			perror("seek");
 			return -1; /* If seek failed, lastwhere did
 				      not change */
 		}
 		This->lastwhere = where;
 	}

 #ifdef OS_hpux
 	/*
 	 * On HP/UX, we can not write more than MAX_LEN bytes in one go.
 	 * If more are written, the write fails with EINVAL
 	 */
 	#define MAX_SCSI_LEN (127*1024)
 	if(This->size_limited && len > MAX_SCSI_LEN)
 		len = MAX_SCSI_LEN;
 #endif
 	ret = io(This->fd, buf, len);

 #ifdef OS_hpux
 	if (ret == -1 &&
 		errno == EINVAL && /* if we got EINVAL */
 		len > MAX_SCSI_LEN) {
 		This->size_limited = 1;
 		len = MAX_SCSI_LEN;
 		ret = io(This->fd, buf, len);
 	}
 #endif

 	if ( ret == -1 ){
 		perror("plain_io");
 		return -1;
 	}
 	This->lastwhere = where + ret;
 	return ret;
 }

 static ssize_t file_read(Stream_t *Stream, char *buf, size_t len)
 {
 	DeclareThis(SimpleFile_t);
 	return file_io(This, buf, This->lastwhere, len, read);
 }

 static ssize_t file_write(Stream_t *Stream, char *buf, size_t len)
 {
 	DeclareThis(SimpleFile_t);
 	return file_io(This, buf, This->lastwhere, len, (iofn) write);
 }

 static ssize_t file_pread(Stream_t *Stream, char *buf,
 			  mt_off_t where, size_t len)
 {
 	DeclareThis(SimpleFile_t);
 	return file_io(This, buf, where, len, read);
 }

 static ssize_t file_pwrite(Stream_t *Stream, char *buf,
 			   mt_off_t where, size_t len)
 {
 	DeclareThis(SimpleFile_t);
 	return file_io(This, buf, where, len, (iofn) write);
 }

 static int file_flush(Stream_t *Stream UNUSEDP)
 {
 #if 0
 	DeclareThis(SimpleFile_t);

 	return fsync(This->fd);
 #endif
 	return 0;
 }

 static int file_free(Stream_t *Stream)
 {
 	DeclareThis(SimpleFile_t);

 	if (This->fd > 2)
 		return close(This->fd);
 	else
 		return 0;
 }

 static int init_geom_with_reg(int fd, struct device *dev,
 			      struct device *orig_dev,
 			      struct MT_STAT *statbuf) {
 	if(S_ISREG(statbuf->st_mode)) {
 		/* Regular file (image file) */
 		mt_off_t sectors;
 		if(statbuf->st_size == 0) {
 			/* zero sized image => newly created.
 			   Size not actually known...
 			*/
 			return 0;
 		}
 		sectors = statbuf->st_size /
 			(mt_off_t)(dev->sector_size ? dev->sector_size : 512);
 		dev->tot_sectors =
 			((smt_off_t) sectors > UINT32_MAX)
 			? UINT32_MAX
 			: (uint32_t) sectors;
 		return 0;
 	} else {
 		/* All the rest (devices, etc.) */
 		return init_geom(fd, dev, orig_dev, statbuf);
 	}
 }

 static int file_geom(Stream_t *Stream, struct device *dev,
 		     struct device *orig_dev)
 {
 	int ret;
 	DeclareThis(SimpleFile_t);

 	if(dev->sector_size && dev->sector_size != 512) {
 		dev->sectors =
 			(uint16_t) (dev->sectors * dev->sector_size / 512);
 	}

 #ifdef JPD
 	printf("file_geom:media=%0X=>cyl=%d,heads=%d,sects=%d,ssize=%d,use2m=%X\n",
 	       media, dev->tracks, dev->heads, dev->sectors, dev->ssize,
 	       dev->use_2m);
 #endif
 	ret = init_geom_with_reg(This->fd,dev, orig_dev, &This->statbuf);
 	if(dev->sector_size && dev->sector_size != 512) {
 		dev->sectors =
 			(uint16_t) (dev->sectors * 512 / dev->sector_size);
 	}
 #ifdef JPD
 	printf("f_geom: after init_geom(), sects=%d\n", dev->sectors);
 #endif
 	return ret;
 }


 static int file_data(Stream_t *Stream, time_t *date, mt_off_t *size,
 		     int *type, uint32_t *address)
 {
 	DeclareThis(SimpleFile_t);

 	if(date)
 		*date = This->statbuf.st_mtime;
 	if(size)
 		*size = This->statbuf.st_size;
 	if(type)
 		*type = S_ISDIR(This->statbuf.st_mode);
 	if(address)
 		*address = 0;
 	return 0;
 }

 static int file_discard(Stream_t *Stream UNUSEDP)
 {
 #ifdef BLKFLSBUF
 	int ret;
 	DeclareThis(SimpleFile_t);
 	ret= ioctl(This->fd, BLKFLSBUF);
 	if(ret < 0)
 		perror("BLKFLSBUF");
 	return ret;
 #else
 	return 0;
 #endif
 }

 static Class_t SimpleFileClass = {
 	file_read,
 	file_write,
 	file_pread,
 	file_pwrite,
 	file_flush,
 	file_free,
 	file_geom,
 	file_data,
 	0, /* pre_allocate */
 	0, /* dos-convert */
 	file_discard
 };


 int LockDevice(int fd, struct device *dev,
 	       int locked, int lockMode,
 	       char *errmsg)
 {
 #ifndef __EMX__
 #ifndef __CYGWIN__
 #ifndef OS_mingw32msvc
 	/* lock the device on writes */
 	if (locked && lock_dev(fd, (lockMode&O_ACCMODE) == O_RDWR, dev)) {
 		if(errmsg)
 #ifdef HAVE_SNPRINTF
 			snprintf(errmsg,199,
 				"plain floppy: device \"%s\" busy (%s):",
 				dev ? dev->name : "unknown", strerror(errno));
 #else
 			sprintf(errmsg,
 				"plain floppy: device \"%s\" busy (%s):",
 				(dev && strlen(dev->name) < 50) ?
 				 dev->name : "unknown", strerror(errno));
 #endif

 		if(errno != EOPNOTSUPP || (lockMode&O_ACCMODE) == O_RDWR) {
 			/* If error is "not supported", and we're only
 			 * reading from the device anyways, then ignore. Some
 			 * OS'es don't support locks on read-only devices, even
 			 * if they are shared (read-only) locks */
 			return -1;
 		}
 	}
 #endif
 #endif
 #endif
 	return 0;
 }

 Stream_t *SimpleFileOpen(struct device *dev, struct device *orig_dev,
 			 const char *name, int mode, char *errmsg,
 			 int mode2, int locked, mt_off_t *maxSize) {
 	return SimpleFileOpenWithLm(dev, orig_dev, name, mode,
 				    errmsg, mode2, locked, mode, maxSize,
 				    NULL);
 }

 Stream_t *SimpleFileOpenWithLm(struct device *dev, struct device *orig_dev,
 			       const char *name, int mode, char *errmsg,
 			       int mode2, int locked, int lockMode,
 			       mt_off_t *maxSize, int *geomFailure)
 {
 	SimpleFile_t *This;
 #ifdef __EMX__
 HFILE FileHandle;
 ULONG Action;
 APIRET rc;
 #endif
 	if (IS_SCSI(dev))
 		return NULL;
 	This = New(SimpleFile_t);
 	if (!This){
 		printOom();
 		return 0;
 	}
 	memset((void*)This, 0, sizeof(SimpleFile_t));
 	This->seekable = 1;
 #ifdef OS_hpux
 	This->size_limited = 0;
 #endif
 	init_head(&This->head, &SimpleFileClass, NULL);
 	if (!name || strcmp(name,"-") == 0 ){
 		if (mode == O_RDONLY)
 			This->fd = 0;
 		else
 			This->fd = 1;
 		This->seekable = 0;
 		if (MT_FSTAT(This->fd, &This->statbuf) < 0) {
 		    Free(This);
 		    if(errmsg)
 #ifdef HAVE_SNPRINTF
 			snprintf(errmsg,199,"Can't stat -: %s",
 				strerror(errno));
 #else
 			sprintf(errmsg,"Can't stat -: %s",
 				strerror(errno));
 #endif
 		    return NULL;
 		}

 		return &This->head;
 	}


 	if(dev) {
 		if(!(mode2 & NO_PRIV))
 			This->privileged = IS_PRIVILEGED(dev);
 		mode |= dev->mode;
 	}

 	precmd(dev);
 	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
 		reclaim_privs();

 #ifdef __EMX__
 #define DOSOPEN_FLAGS	(OPEN_FLAGS_DASD | OPEN_FLAGS_WRITE_THROUGH | \
 			OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_RANDOM | \
 			OPEN_FLAGS_NO_CACHE)
 #define DOSOPEN_FD_ACCESS (OPEN_SHARE_DENYREADWRITE | OPEN_ACCESS_READWRITE)
 #define DOSOPEN_HD_ACCESS (OPEN_SHARE_DENYNONE | OPEN_ACCESS_READONLY)

 	if (isalpha(*name) && (*(name+1) == ':')) {
 		rc = DosOpen(
 			name, &FileHandle, &Action, 0L, FILE_NORMAL,
 			OPEN_ACTION_OPEN_IF_EXISTS, DOSOPEN_FLAGS |
 			(IS_NOLOCK(dev)?DOSOPEN_HD_ACCESS:DOSOPEN_FD_ACCESS),
 			0L);
 #if DEBUG
 		if (rc != NO_ERROR) fprintf (stderr, "DosOpen() returned %d\n", rc);
 #endif
 		if (!IS_NOLOCK(dev)) {
 			rc = DosDevIOCtl(
 			FileHandle, 0x08L, DSK_LOCKDRIVE, 0, 0, 0, 0, 0, 0);
 #if DEBUG
 			if (rc != NO_ERROR) fprintf (stderr, "DosDevIOCtl() returned %d\n", rc);
 #endif
 		}
 		if (rc == NO_ERROR)
 			This->fd = _imphandle(FileHandle); else This->fd = -1;
 	} else
 #endif
 	    {
 		    This->fd = open(name, mode | O_LARGEFILE | O_BINARY,
 				    IS_NOLOCK(dev)?0444:0666);
 	    }

 	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
 		drop_privs();

 	if (This->fd < 0) {
 		if(errmsg) {
 #ifdef HAVE_SNPRINTF
 			snprintf(errmsg, 199, "Can't open %s: %s",
 				name, strerror(errno));
 #else
 			sprintf(errmsg, "Can't open %s: %s",
 				name, strerror(errno));
 #endif
 		}
 		goto exit_1;
 	}

 	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
 		closeExec(This->fd);

 #ifdef __EMX__
 	if (*(name+1) != ':')
 #endif
 	if (MT_FSTAT(This->fd, &This->statbuf) < 0
 #ifdef OS_mingw32msvc
 	    && strncmp(name, "\\\\.\\", 4) != 0
 #endif
 	   ) {
 		if(errmsg) {
 #ifdef HAVE_SNPRINTF
 			snprintf(errmsg,199,"Can't stat %s: %s",
 				name, strerror(errno));
 #else
 			if(strlen(name) > 50) {
 			    sprintf(errmsg,"Can't stat file: %s",
 				    strerror(errno));
 			} else {
 			    sprintf(errmsg,"Can't stat %s: %s",
 				name, strerror(errno));
 			}
 #endif
 		}
 		goto exit_0;
 	}

 	if(LockDevice(This->fd, dev, locked, lockMode, errmsg) < 0)
 		goto exit_0;

 	/* set default parameters, if needed */
 	if (dev){
 		errno=0;
 		if (((!IS_MFORMAT_ONLY(dev) && dev->tracks) ||
 		     mode2 & ALWAYS_GET_GEOMETRY) &&
 		    init_geom_with_reg(This->fd, dev, orig_dev,
 				       &This->statbuf)){
 			if(geomFailure && (errno==EBADF || errno==EPERM)) {
 				*geomFailure=1;
 				return NULL;
 			} else if(errmsg)
 				sprintf(errmsg,"init: set default params");
 			goto exit_0;
 		}
 	}

 	if(maxSize)
 		*maxSize = max_off_t_seek;

 	This->lastwhere = 0;

 	return &This->head;
  exit_0:
 	close(This->fd);
  exit_1:
 	Free(This);
 	return NULL;
 }

 int get_fd(Stream_t *Stream)
 {
 	Class_t *clazz;
 	DeclareThis(SimpleFile_t);
 	clazz = This->head.Class;
 	if(clazz != &SimpleFileClass)
 	  return -1;
 	else
 	  return This->fd;
 }
	/* Copyright 1995-2007,2009,2011 Alain Knaff.
	* This file is part of mtools.
	*
	* Mtools is free software: you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation, either version 3 of the License, or
	* (at your option) any later version.
	*
	* Mtools is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with Mtools. If not, see <http://www.gnu.org/licenses/>.
	*
	* Io to a plain file or device
	*
	* written by:
	*
	* Alain L. Knaff
	* alain@knaff.lu
	*
	*/

	#include "sysincludes.h"
	#include "stream.h"
	#include "mtools.h"
	#include "msdos.h"
	#include "open_image.h"
	#include "devices.h"
	#include "plain_io.h"
	#include "llong.h"

	#ifdef HAVE_LINUX_FS_H
	# include <linux/fs.h>
	#endif

	typedef struct SimpleFile_t {
	struct Stream_t head;

	struct MT_STAT statbuf;
	int fd;
	mt_off_t lastwhere;
	int seekable;
	int privileged;
	#ifdef OS_hpux
	int size_limited;
	#endif
	} SimpleFile_t;


	#include "lockdev.h"

	typedef ssize_t (iofn) (int, void , size_t);

	static ssize_t file_io(SimpleFile_t This, char buf,
	mt_off_t where, size_t len,
	iofn io)
	{
	ssize_t ret;

	if (This->seekable && where != This->lastwhere ){
	if(mt_lseek( This->fd, where, SEEK_SET) < 0 ){
	perror("seek");
	return -1; /* If seek failed, lastwhere did
	not change */
	}
	This->lastwhere = where;
	}

	#ifdef OS_hpux
	/*
	* On HP/UX, we can not write more than MAX_LEN bytes in one go.
	* If more are written, the write fails with EINVAL
	*/
	#define MAX_SCSI_LEN (127*1024)
	if(This->size_limited && len > MAX_SCSI_LEN)
	len = MAX_SCSI_LEN;
	#endif
	ret = io(This->fd, buf, len);

	#ifdef OS_hpux
	if (ret == -1 &&
	errno == EINVAL && /* if we got EINVAL */
	len > MAX_SCSI_LEN) {
	This->size_limited = 1;
	len = MAX_SCSI_LEN;
	ret = io(This->fd, buf, len);
	}
	#endif

	if ( ret == -1 ){
	perror("plain_io");
	return -1;
	}
	This->lastwhere = where + ret;
	return ret;
	}

	static ssize_t file_read(Stream_t Stream, char buf, size_t len)
	{
	DeclareThis(SimpleFile_t);
	return file_io(This, buf, This->lastwhere, len, read);
	}

	static ssize_t file_write(Stream_t Stream, char buf, size_t len)
	{
	DeclareThis(SimpleFile_t);
	return file_io(This, buf, This->lastwhere, len, (iofn) write);
	}

	static ssize_t file_pread(Stream_t Stream, char buf,
	mt_off_t where, size_t len)
	{
	DeclareThis(SimpleFile_t);
	return file_io(This, buf, where, len, read);
	}

	static ssize_t file_pwrite(Stream_t Stream, char buf,
	mt_off_t where, size_t len)
	{
	DeclareThis(SimpleFile_t);
	return file_io(This, buf, where, len, (iofn) write);
	}

	static int file_flush(Stream_t *Stream UNUSEDP)
	{
	#if 0
	DeclareThis(SimpleFile_t);

	return fsync(This->fd);
	#endif
	return 0;
	}

	static int file_free(Stream_t *Stream)
	{
	DeclareThis(SimpleFile_t);

	if (This->fd > 2)
	return close(This->fd);
	else
	return 0;
	}

	static int init_geom_with_reg(int fd, struct device *dev,
	struct device *orig_dev,
	struct MT_STAT *statbuf) {
	if(S_ISREG(statbuf->st_mode)) {
	/* Regular file (image file) */
	mt_off_t sectors;
	if(statbuf->st_size == 0) {
	/* zero sized image => newly created.
	Size not actually known...
	*/
	return 0;
	}
	sectors = statbuf->st_size /
	(mt_off_t)(dev->sector_size ? dev->sector_size : 512);
	dev->tot_sectors =
	((smt_off_t) sectors > UINT32_MAX)
	? UINT32_MAX
	: (uint32_t) sectors;
	return 0;
	} else {
	/* All the rest (devices, etc.) */
	return init_geom(fd, dev, orig_dev, statbuf);
	}
	}

	static int file_geom(Stream_t Stream, struct device dev,
	struct device *orig_dev)
	{
	int ret;
	DeclareThis(SimpleFile_t);

	if(dev->sector_size && dev->sector_size != 512) {
	dev->sectors =
	(uint16_t) (dev->sectors * dev->sector_size / 512);
	}

	#ifdef JPD
	printf("file_geom:media=%0X=>cyl=%d,heads=%d,sects=%d,ssize=%d,use2m=%X\n",
	media, dev->tracks, dev->heads, dev->sectors, dev->ssize,
	dev->use_2m);
	#endif
	ret = init_geom_with_reg(This->fd,dev, orig_dev, &This->statbuf);
	if(dev->sector_size && dev->sector_size != 512) {
	dev->sectors =
	(uint16_t) (dev->sectors * 512 / dev->sector_size);
	}
	#ifdef JPD
	printf("f_geom: after init_geom(), sects=%d\n", dev->sectors);
	#endif
	return ret;
	}


	static int file_data(Stream_t Stream, time_t date, mt_off_t *size,
	int type, uint32_t address)
	{
	DeclareThis(SimpleFile_t);

	if(date)
	*date = This->statbuf.st_mtime;
	if(size)
	*size = This->statbuf.st_size;
	if(type)
	*type = S_ISDIR(This->statbuf.st_mode);
	if(address)
	*address = 0;
	return 0;
	}

	static int file_discard(Stream_t *Stream UNUSEDP)
	{
	#ifdef BLKFLSBUF
	int ret;
	DeclareThis(SimpleFile_t);
	ret= ioctl(This->fd, BLKFLSBUF);
	if(ret < 0)
	perror("BLKFLSBUF");
	return ret;
	#else
	return 0;
	#endif
	}

	static Class_t SimpleFileClass = {
	file_read,
	file_write,
	file_pread,
	file_pwrite,
	file_flush,
	file_free,
	file_geom,
	file_data,
	0, /* pre_allocate */
	0, /* dos-convert */
	file_discard
	};


	int LockDevice(int fd, struct device *dev,
	int locked, int lockMode,
	char *errmsg)
	{
	#ifndef __EMX__
	#ifndef __CYGWIN__
	#ifndef OS_mingw32msvc
	/* lock the device on writes */
	if (locked && lock_dev(fd, (lockMode&O_ACCMODE) == O_RDWR, dev)) {
	if(errmsg)
	#ifdef HAVE_SNPRINTF
	snprintf(errmsg,199,
	"plain floppy: device \"%s\" busy (%s):",
	dev ? dev->name : "unknown", strerror(errno));
	#else
	sprintf(errmsg,
	"plain floppy: device \"%s\" busy (%s):",
	(dev && strlen(dev->name) < 50) ?
	dev->name : "unknown", strerror(errno));
	#endif

	if(errno != EOPNOTSUPP \|\| (lockMode&O_ACCMODE) == O_RDWR) {
	/* If error is "not supported", and we're only
	* reading from the device anyways, then ignore. Some
	* OS'es don't support locks on read-only devices, even
	* if they are shared (read-only) locks */
	return -1;
	}
	}
	#endif
	#endif
	#endif
	return 0;
	}

	Stream_t SimpleFileOpen(struct device dev, struct device *orig_dev,
	const char name, int mode, char errmsg,
	int mode2, int locked, mt_off_t *maxSize) {
	return SimpleFileOpenWithLm(dev, orig_dev, name, mode,
	errmsg, mode2, locked, mode, maxSize,
	NULL);
	}

	Stream_t SimpleFileOpenWithLm(struct device dev, struct device *orig_dev,
	const char name, int mode, char errmsg,
	int mode2, int locked, int lockMode,
	mt_off_t maxSize, int geomFailure)
	{
	SimpleFile_t *This;
	#ifdef __EMX__
	HFILE FileHandle;
	ULONG Action;
	APIRET rc;
	#endif
	if (IS_SCSI(dev))
	return NULL;
	This = New(SimpleFile_t);
	if (!This){
	printOom();
	return 0;
	}
	memset((void*)This, 0, sizeof(SimpleFile_t));
	This->seekable = 1;
	#ifdef OS_hpux
	This->size_limited = 0;
	#endif
	init_head(&This->head, &SimpleFileClass, NULL);
	if (!name \|\| strcmp(name,"-") == 0 ){
	if (mode == O_RDONLY)
	This->fd = 0;
	else
	This->fd = 1;
	This->seekable = 0;
	if (MT_FSTAT(This->fd, &This->statbuf) < 0) {
	Free(This);
	if(errmsg)
	#ifdef HAVE_SNPRINTF
	snprintf(errmsg,199,"Can't stat -: %s",
	strerror(errno));
	#else
	sprintf(errmsg,"Can't stat -: %s",
	strerror(errno));
	#endif
	return NULL;
	}

	return &This->head;
	}


	if(dev) {
	if(!(mode2 & NO_PRIV))
	This->privileged = IS_PRIVILEGED(dev);
	mode \|= dev->mode;
	}

	precmd(dev);
	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
	reclaim_privs();

	#ifdef __EMX__
	#define DOSOPEN_FLAGS (OPEN_FLAGS_DASD \| OPEN_FLAGS_WRITE_THROUGH \| \
	OPEN_FLAGS_NOINHERIT \| OPEN_FLAGS_RANDOM \| \
	OPEN_FLAGS_NO_CACHE)
	#define DOSOPEN_FD_ACCESS (OPEN_SHARE_DENYREADWRITE \| OPEN_ACCESS_READWRITE)
	#define DOSOPEN_HD_ACCESS (OPEN_SHARE_DENYNONE \| OPEN_ACCESS_READONLY)

	if (isalpha(name) && ((name+1) == ':')) {
	rc = DosOpen(
	name, &FileHandle, &Action, 0L, FILE_NORMAL,
	OPEN_ACTION_OPEN_IF_EXISTS, DOSOPEN_FLAGS \|
	(IS_NOLOCK(dev)?DOSOPEN_HD_ACCESS:DOSOPEN_FD_ACCESS),
	0L);
	#if DEBUG
	if (rc != NO_ERROR) fprintf (stderr, "DosOpen() returned %d\n", rc);
	#endif
	if (!IS_NOLOCK(dev)) {
	rc = DosDevIOCtl(
	FileHandle, 0x08L, DSK_LOCKDRIVE, 0, 0, 0, 0, 0, 0);
	#if DEBUG
	if (rc != NO_ERROR) fprintf (stderr, "DosDevIOCtl() returned %d\n", rc);
	#endif
	}
	if (rc == NO_ERROR)
	This->fd = _imphandle(FileHandle); else This->fd = -1;
	} else
	#endif
	{
	This->fd = open(name, mode \| O_LARGEFILE \| O_BINARY,
	IS_NOLOCK(dev)?0444:0666);
	}

	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
	drop_privs();

	if (This->fd < 0) {
	if(errmsg) {
	#ifdef HAVE_SNPRINTF
	snprintf(errmsg, 199, "Can't open %s: %s",
	name, strerror(errno));
	#else
	sprintf(errmsg, "Can't open %s: %s",
	name, strerror(errno));
	#endif
	}
	goto exit_1;
	}

	if(IS_PRIVILEGED(dev) && !(mode2 & NO_PRIV))
	closeExec(This->fd);

	#ifdef __EMX__
	if (*(name+1) != ':')
	#endif
	if (MT_FSTAT(This->fd, &This->statbuf) < 0
	#ifdef OS_mingw32msvc
	&& strncmp(name, "\\\\.\\", 4) != 0
	#endif
	) {
	if(errmsg) {
	#ifdef HAVE_SNPRINTF
	snprintf(errmsg,199,"Can't stat %s: %s",
	name, strerror(errno));
	#else
	if(strlen(name) > 50) {
	sprintf(errmsg,"Can't stat file: %s",
	strerror(errno));
	} else {
	sprintf(errmsg,"Can't stat %s: %s",
	name, strerror(errno));
	}
	#endif
	}
	goto exit_0;
	}

	if(LockDevice(This->fd, dev, locked, lockMode, errmsg) < 0)
	goto exit_0;

	/* set default parameters, if needed */
	if (dev){
	errno=0;
	if (((!IS_MFORMAT_ONLY(dev) && dev->tracks) \|\|
	mode2 & ALWAYS_GET_GEOMETRY) &&
	init_geom_with_reg(This->fd, dev, orig_dev,
	&This->statbuf)){
	if(geomFailure && (errno==EBADF \|\| errno==EPERM)) {
	*geomFailure=1;
	return NULL;
	} else if(errmsg)
	sprintf(errmsg,"init: set default params");
	goto exit_0;
	}
	}

	if(maxSize)
	*maxSize = max_off_t_seek;

	This->lastwhere = 0;

	return &This->head;
	exit_0:
	close(This->fd);
	exit_1:
	Free(This);
	return NULL;
	}

	int get_fd(Stream_t *Stream)
	{
	Class_t *clazz;
	DeclareThis(SimpleFile_t);
	clazz = This->head.Class;
	if(clazz != &SimpleFileClass)
	return -1;
	else
	return This->fd;
	}