* errno.cc (errmap): Map ERROR_SHARING_VIOLATION to EBUSY,

ERROR_EOM_OVERFLOW and ERROR_NO_DATA_DETECTED to EIO.  Add mappings
	for ERROR_NO_MEDIA_IN_DRIVE, ERROR_DEVICE_REQUIRES_CLEANING and
	ERROR_DEVICE_DOOR_OPEN.
	* fhandler.h (class fhandler_dev_raw): Drop varblkop member.
	(fhandler_dev_raw::is_eom): De-virtualize.
	(fhandler_dev_raw::is_eof): Ditto.
	(class fhandler_dev_tape): Drop lasterr and dp member.  Add mt_mtx
	member.  Drop all private methods formerly used by ioctl.
	(fhandler_dev_tape::is_rewind_device): Use get_minor for clarity.
	(fhandler_dev_tape::driveno): New method.
	(fhandler_dev_tape::drive_init): New method.
	(fhandler_dev_tape::clear): Remove method.
	(fhandler_dev_tape::is_eom): Ditto.
	(fhandler_dev_tape::is_eof): Ditto.
	(fhandler_dev_tape::write_file): Ditto.
	(fhandler_dev_tape::read_file): Ditto.
	(fhandler_dev_tape::_lock): New method.
	(fhandler_dev_tape::unlock): New method.
	(fhandler_dev_tape::raw_read): New method.
	(fhandler_dev_tape::raw_write): New method.
	* fhandler_raw.cc (fhandler_dev_raw::is_eom): New method.
	(fhandler_dev_raw::is_eof): New method.
	(fhandler_dev_raw::open): Allow setting write through option by
	using the O_TEXT flag as ... flag.
	(fhandler_dev_raw::writebuf): Remove usage of varblkop and other
	tape specific code.
	(fhandler_dev_raw::raw_read): Ditto.
	(fhandler_dev_raw::dup): Ditto.
	* fhandler_tape.cc: Rewrite tape operations entirely.  Implement
	new tape driver classes mtinfo, mtinfo_drive and mtinfo_part.
	Reduce fhandler_dev_tape methods to mostly just calling appropriate
	mtinfo_drive methods.
	(mtinfo_init): New function adding the mtinfo shared memory area.
	* mtinfo.h: New file, containing the definition of the new tape
	driver classes.
	* shared.cc: Include mtinfo.h.
	(offsets): Add entry for mtinfo shared memory area.
	(memory_init): Call mtinfo_init.
	* shared_info.h (shared_locations): Add SH_MTINFO shared location.
	* include/cygwin/mtio.h: Change and add various comments.  Add GMT_xxx
	macros for new generic flags.  Add MT_ST_xxx bitfield definitions
	for MTSETDRVBUFFER ioctl.
	* include/cygwin/version.h: Bump API minor version number.

winsup/cygwin/ChangeLog

@@ -1,3 +1,50 @@
+2004-03-26  Corinna Vinschen  <corinna@vinschen.de>
+
+	* errno.cc (errmap): Map ERROR_SHARING_VIOLATION to EBUSY,
+	ERROR_EOM_OVERFLOW and ERROR_NO_DATA_DETECTED to EIO.  Add mappings
+	for ERROR_NO_MEDIA_IN_DRIVE, ERROR_DEVICE_REQUIRES_CLEANING and
+	ERROR_DEVICE_DOOR_OPEN.
+	* fhandler.h (class fhandler_dev_raw): Drop varblkop member.
+	(fhandler_dev_raw::is_eom): De-virtualize.
+	(fhandler_dev_raw::is_eof): Ditto.
+	(class fhandler_dev_tape): Drop lasterr and dp member.  Add mt_mtx
+	member.  Drop all private methods formerly used by ioctl.
+	(fhandler_dev_tape::is_rewind_device): Use get_minor for clarity.
+	(fhandler_dev_tape::driveno): New method.
+	(fhandler_dev_tape::drive_init): New method.
+	(fhandler_dev_tape::clear): Remove method.
+	(fhandler_dev_tape::is_eom): Ditto.
+	(fhandler_dev_tape::is_eof): Ditto.
+	(fhandler_dev_tape::write_file): Ditto.
+	(fhandler_dev_tape::read_file): Ditto.
+	(fhandler_dev_tape::_lock): New method.
+	(fhandler_dev_tape::unlock): New method.
+	(fhandler_dev_tape::raw_read): New method.
+	(fhandler_dev_tape::raw_write): New method.
+	* fhandler_raw.cc (fhandler_dev_raw::is_eom): New method.
+	(fhandler_dev_raw::is_eof): New method.
+	(fhandler_dev_raw::open): Allow setting write through option by
+	using the O_TEXT flag as ... flag.
+	(fhandler_dev_raw::writebuf): Remove usage of varblkop and other
+	tape specific code.
+	(fhandler_dev_raw::raw_read): Ditto.
+	(fhandler_dev_raw::dup): Ditto.
+	* fhandler_tape.cc: Rewrite tape operations entirely.  Implement
+	new tape driver classes mtinfo, mtinfo_drive and mtinfo_part.
+	Reduce fhandler_dev_tape methods to mostly just calling appropriate
+	mtinfo_drive methods.
+	(mtinfo_init): New function adding the mtinfo shared memory area.
+	* mtinfo.h: New file, containing the definition of the new tape
+	driver classes.
+	* shared.cc: Include mtinfo.h.
+	(offsets): Add entry for mtinfo shared memory area.
+	(memory_init): Call mtinfo_init.
+	* shared_info.h (shared_locations): Add SH_MTINFO shared location.
+	* include/cygwin/mtio.h: Change and add various comments.  Add GMT_xxx
+	macros for new generic flags.  Add MT_ST_xxx bitfield definitions
+	for MTSETDRVBUFFER ioctl.
+	* include/cygwin/version.h: Bump API minor version number.
+
 2004-03-26  Christopher Faylor  <cgf@redhat.com>
 
 	* path.cc (path_conv::check): Use 'strchr' rather than 'strrchr' to

winsup/cygwin/errno.cc

@@ -48,7 +48,7 @@ static NO_COPY struct
   X (NO_MORE_FILES,		ENMFILE),
   X (WRITE_PROTECT,		EROFS),
   X (BAD_UNIT,			ENODEV),
-  X (SHARING_VIOLATION,		EACCES),
+  X (SHARING_VIOLATION,		EBUSY),
   X (LOCK_VIOLATION,		EACCES),
   X (SHARING_BUFFER_EXCEEDED,	ENOLCK),
   X (HANDLE_EOF,		ENODATA),
@@ -101,10 +101,10 @@ static NO_COPY struct
   X (IO_DEVICE,			EIO),
   X (NOT_OWNER,			EPERM),
   X (END_OF_MEDIA,		ENOSPC),
-  X (EOM_OVERFLOW,		ENOSPC),
+  X (EOM_OVERFLOW,		EIO),
   X (BEGINNING_OF_MEDIA,	EIO),
   X (SETMARK_DETECTED,		EIO),
-  X (NO_DATA_DETECTED,		ENOSPC),
+  X (NO_DATA_DETECTED,		EIO),
   X (POSSIBLE_DEADLOCK,		EDEADLOCK),
   X (CRC,			EIO),
   X (NEGATIVE_SEEK,		EINVAL),
@@ -116,6 +116,9 @@ static NO_COPY struct
   X (INVALID_BLOCK_LENGTH,	EIO),
   X (BUS_RESET,			EIO),
   X (FILEMARK_DETECTED,		EIO),
+  X (NO_MEDIA_IN_DRIVE,		ENOMEDIUM),
+  X (DEVICE_REQUIRES_CLEANING,	EIO),
+  X (DEVICE_DOOR_OPEN,		EIO),
   { 0, NULL, 0}
 };
 

winsup/cygwin/fhandler.h

@@ -509,7 +509,6 @@ class fhandler_dev_raw: public fhandler_base
   int lastblk_to_read : 1;
   int is_writing      : 1;
   int has_written     : 1;
-  int varblkop	      : 1;
 
   virtual void clear (void);
   virtual BOOL write_file (const void *buf, DWORD to_write,
@@ -518,9 +517,9 @@ class fhandler_dev_raw: public fhandler_base
   virtual int writebuf (void);
 
   /* returns not null, if `win_error' determines an end of media condition */
-  virtual int is_eom(int win_error) = 0;
+  virtual int is_eom(int win_error);
   /* returns not null, if `win_error' determines an end of file condition */
-  virtual int is_eof(int win_error) = 0;
+  virtual int is_eof(int win_error);
 
   fhandler_dev_raw ();
 
@@ -569,18 +568,14 @@ class fhandler_dev_floppy: public fhandler_dev_raw
 
 class fhandler_dev_tape: public fhandler_dev_raw
 {
-  int lasterr;
+  HANDLE mt_mtx;
-  TAPE_GET_DRIVE_PARAMETERS dp;
 
-  bool is_rewind_device () { return get_unit () < 128; }
+  bool is_rewind_device () { return get_minor () < 128; }
+  unsigned int driveno () { return (unsigned int) get_minor () & 0x7f; }
+  void drive_init (void);
 
- protected:
+  inline bool _lock ();
-  virtual void clear (void);
+  inline int unlock (int ret = 0);
-  virtual int is_eom (int win_error);
-  virtual int is_eof (int win_error);
-  virtual BOOL write_file (const void *buf, DWORD to_write,
-			   DWORD *written, int *err);
-  virtual BOOL read_file (void *buf, DWORD to_read, DWORD *read, int *err);
 
  public:
   fhandler_dev_tape ();
@@ -588,33 +583,15 @@ class fhandler_dev_tape: public fhandler_dev_raw
   virtual int open (int flags, mode_t mode = 0);
   virtual int close (void);
 
+  void raw_read (void *ptr, size_t& ulen);
+  int raw_write (const void *ptr, size_t ulen);
+
   virtual _off64_t lseek (_off64_t offset, int whence);
 
   virtual int __stdcall fstat (struct __stat64 *buf) __attribute__ ((regparm (2)));
 
   virtual int dup (fhandler_base *child);
-
   virtual int ioctl (unsigned int cmd, void *buf);
-
- private:
-  inline bool tape_get_feature (DWORD parm)
-    {
-      return ((parm & TAPE_DRIVE_HIGH_FEATURES)
-	      ? ((dp.FeaturesHigh & parm) != 0)
-	      : ((dp.FeaturesLow & parm) != 0));
-    }
-  int tape_error (const char *txt);
-  int tape_write_marks (int marktype, DWORD len);
-  int tape_get_pos (unsigned long *block, unsigned long *partition = NULL);
-  int tape_set_pos (int mode, long count, bool sfm_func = false);
-  int _tape_set_pos (int mode, long count, int partition = 0);
-  int tape_erase (int mode);
-  int tape_prepare (int action);
-  int tape_set_blocksize (long count);
-  int tape_status (struct mtget *get);
-  int tape_compression (long count);
-  int tape_partition (long count);
-  int tape_set_partition (long count);
 };
 
 /* Standard disk file */

winsup/cygwin/fhandler_raw.cc

@@ -37,9 +37,21 @@ fhandler_dev_raw::clear (void)
   eom_detected = 0;
   eof_detected = 0;
   lastblk_to_read = 0;
-  varblkop = 0;
 }
 
+int
+fhandler_dev_raw::is_eom (int win_error)
+{
+  return 0;
+}
+
+int
+fhandler_dev_raw::is_eof (int)
+{
+  return 0;
+}
+
+
 /* Wrapper functions to allow fhandler_dev_tape to detect and care for
    media changes and bus resets. */
 
@@ -76,16 +88,13 @@ fhandler_dev_raw::writebuf (void)
   DWORD written;
   int ret = 0;
 
-  if (!varblkop && is_writing && devbuf && devbufend)
+  if (is_writing && devbuf && devbufend)
     {
       DWORD to_write;
       int ret = 0;
 
       memset (devbuf + devbufend, 0, devbufsiz - devbufend);
-      if (get_major () != DEV_TAPE_MAJOR)
+      to_write = ((devbufend - 1) / 512 + 1) * 512;
-	to_write = ((devbufend - 1) / 512 + 1) * 512;
-      else
-	to_write = devbufsiz;
       if (!write_file (devbuf, to_write, &written, &ret)
 	  && is_eom (ret))
 	eom_detected = 1;
@@ -141,7 +150,7 @@ fhandler_dev_raw::open (int flags, mode_t)
     }
 
   /* Check for illegal flags. */
-  if (flags & (O_APPEND | O_EXCL))
+  if (get_major () != DEV_TAPE_MAJOR && (flags & (O_APPEND | O_EXCL)))
     {
       set_errno (EINVAL);
       return 0;
@@ -162,11 +171,16 @@ fhandler_dev_raw::open (int flags, mode_t)
   WCHAR devname[CYG_MAX_PATH + 1];
   str2buf2uni (dev, devname, get_win32_name ());
   OBJECT_ATTRIBUTES attr;
+  ULONG options = FILE_SYNCHRONOUS_IO_NONALERT;
+  /* The O_TEXT flag is used to indicate write-through on tape devices */
+  if (get_major () == DEV_TAPE_MAJOR && (flags & O_TEXT))
+    options |= FILE_WRITE_THROUGH;
+  flags &= ~O_TEXT;
   InitializeObjectAttributes (&attr, &dev, OBJ_CASE_INSENSITIVE, NULL, NULL);
 
   HANDLE h;
   IO_STATUS_BLOCK io;
-  NTSTATUS status = NtOpenFile (&h, access, &attr, &io, wincap.shared (),
+  NTSTATUS status = NtOpenFile (&h, access, &attr, &io, 0 /* excl. access */,
 				FILE_SYNCHRONOUS_IO_NONALERT);
   if (!NT_SUCCESS (status))
     {
@@ -234,7 +248,8 @@ fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
 	    {
 	      bytes_to_read = min (len, devbufend - devbufstart);
 	      debug_printf ("read %d bytes from buffer (rest %d)",
-			    bytes_to_read, devbufend - devbufend);
+			    bytes_to_read,
+			    devbufend - devbufstart - bytes_to_read);
 	      memcpy (p, devbuf + devbufstart, bytes_to_read);
 	      len -= bytes_to_read;
 	      p += bytes_to_read;
@@ -251,10 +266,7 @@ fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
 	    {
 	      if (len >= devbufsiz)
 		{
-		  if (get_major () == DEV_TAPE_MAJOR)
+		  bytes_to_read = (len / 512) * 512;
-		    bytes_to_read = (len / devbufsiz) * devbufsiz;
-		  else
-		    bytes_to_read = (len / 512) * 512;
 		  tgt = p;
 		  debug_printf ("read %d bytes direct from file",bytes_to_read);
 		}
@@ -310,11 +322,6 @@ fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
     {
       if (!is_eof (ret) && !is_eom (ret))
 	{
-	  if (varblkop && ret == ERROR_MORE_DATA)
-	    /* *ulen < blocksize.  Linux returns ENOMEM here
-	       when reading with variable blocksize . */
-	    set_errno (ENOMEM);
-	  else
 	  __seterrno ();
 	  goto err;
 	}
@@ -470,7 +477,6 @@ fhandler_dev_raw::dup (fhandler_base *child)
       fhc->eom_detected = eom_detected;
       fhc->eof_detected = eof_detected;
       fhc->lastblk_to_read = 0;
-      fhc->varblkop = varblkop;
     }
   return ret;
 }

winsup/cygwin/include/cygwin/mtio.h

@@ -35,7 +35,7 @@ struct	mtop {
 };
 
 /* Magnetic Tape operations [Not all operations supported by all drivers]: */
-#define MTRESET 0	/* +reset drive in case of problems */
+#define MTRESET 0	/* reset drive in case of problems */
 #define MTFSF	1	/* forward space over FileMark,
 			 * position at first record of next file
 			 */
@@ -80,15 +80,14 @@ struct	mtop {
 /* structure for MTIOCGET - mag tape get status command */
 
 struct	mtget {
-	long	mt_type;	/* type of magtape device
+	long	mt_type;	/* type of magtape device */
-				 * Cygwin: MT_ISUNKNOWN */
 	long	mt_resid;	/* residual count: (not sure)
 				 *	number of bytes ignored, or
 				 *	number of files not skipped, or
 				 *	number of records not skipped.
 				 *  Cygwin: remaining KB until 1.5.7.
-				 *          active partition since 1.5.8,
+				 *          active partition since 1.5.8
-				 *          same as on linux.
+				 *          (same as on GNU-Linux).
 				 */
 	/* the following registers are device dependent */
 	long	mt_dsreg;	/* status register, Contains blocksize and
@@ -133,17 +132,27 @@ struct	mtpos {
 #define GMT_SM(x)               ((x) & 0x10000000)  /* DDS setmark */
 #define GMT_EOD(x)              ((x) & 0x08000000)  /* DDS EOD */
 #define GMT_WR_PROT(x)          ((x) & 0x04000000)
-/* #define GMT_ ?		((x) & 0x02000000) */
+#define GMT_REP_SM(x)           ((x) & 0x02000000)  /* Cygwin: rep. setmarks */
 #define GMT_ONLINE(x)           ((x) & 0x01000000)
 #define GMT_D_6250(x)           ((x) & 0x00800000)
 #define GMT_D_1600(x)           ((x) & 0x00400000)
 #define GMT_D_800(x)            ((x) & 0x00200000)
-#define GMT_PADDING(x)		((x) & 0x00100000)  /* data padding */
+#define GMT_PADDING(x)          ((x) & 0x00100000)  /* Cygwin: data padding */
-#define GMT_HW_ECC(x)		((x) & 0x00080000)  /* HW error correction */
+#define GMT_HW_ECC(x)           ((x) & 0x00080000)  /* Cygwin: HW error corr. */
 #define GMT_DR_OPEN(x)          ((x) & 0x00040000)  /* door open (no tape) */
-#define GMT_HW_COMP(x)		((x) & 0x00020000)  /* HW compression */
+#define GMT_HW_COMP(x)          ((x) & 0x00020000)  /* Cygwin: HW compression */
 #define GMT_IM_REP_EN(x)        ((x) & 0x00010000)  /* immediate report mode */
-/* 16 generic status bits unused */
+#define GMT_CLN(x)              ((x) & 0x00008000)  /* cleaning requested */
+/* 15 generic status bits unused */
+/* Cygwin only: The below settings are also used by the GNU-Linux SCSI tape
+   driver but they aren't usually reported here.  Unfortunately, there's no
+   other official method to retrieve the values of these settings and
+   reporting them here apparently doesn't hurt. */
+#define GMT_TWO_FM(x)           ((x) & 0x00000080)  /* two fm after write */
+#define GMT_FAST_MTEOM(x)       ((x) & 0x00000040)  /* fast seek to eom */
+#define GMT_AUTO_LOCK(x)        ((x) & 0x00000020)  /* auto door lock on r/w */
+#define GMT_SYSV(x)		((x) & 0x00000010)  /* SYSV read semantics */
+#define GMT_NOWAIT(x)		((x) & 0x00000008)  /* don't wait for positioning commands */
 
 
 /* SCSI-tape specific definitions */
@@ -156,6 +165,33 @@ struct	mtpos {
 #define MT_ST_SOFTERR_SHIFT	0
 #define MT_ST_SOFTERR_MASK	0xffff
 
+/* Bitfields for the MTSETDRVBUFFER ioctl.  */
+#define MT_ST_OPTIONS           0xf0000000
+#define MT_ST_BOOLEANS          0x10000000
+#define MT_ST_SETBOOLEANS       0x30000000
+#define MT_ST_CLEARBOOLEANS     0x40000000
+#define MT_ST_WRITE_THRESHOLD   0x20000000	/* Not supported */
+#define MT_ST_DEF_OPTIONS       0x60000000	/* Not supported */
+#define MT_ST_EOT_WZ_SIZE	0xf0000000	/* Cygwin only */
+
+#define MT_ST_BUFFER_WRITES     0x00000001
+#define MT_ST_ASYNC_WRITES	0x00000002	/* Not supported */
+#define MT_ST_READ_AHEAD        0x00000004	/* Not supported */
+#define MT_ST_DEBUGGING         0x00000008	/* Not supported */
+#define MT_ST_TWO_FM		0x00000010
+#define MT_ST_FAST_MTEOM        0x00000020
+#define MT_ST_AUTO_LOCK		0x00000040
+#define MT_ST_DEF_WRITES        0x00000080	/* Not supported */
+#define MT_ST_CAN_BSR           0x00000100	/* Not supported */
+#define MT_ST_NO_BLKLIMS        0x00000200	/* Not supported */
+#define MT_ST_CAN_PARTITIONS    0x00000400	/* Not supported */
+#define MT_ST_SCSI2LOGICAL      0x00000800	/* Not supported */
+#define MT_ST_SYSV              0x00001000
+#define MT_ST_NOWAIT            0x00002000
+#define MT_ST_ECC		0x00010000	/* Cygwin only */
+#define MT_ST_PADDING		0x00020000	/* Cygwin only */
+#define MT_ST_REPORT_SM		0x00040000	/* Cygwin only */
+
 /*
  * Constants for mt_type. Not all of these are supported,
  * and these are not all of the ones that are supported.

winsup/cygwin/include/cygwin/version.h

@@ -238,12 +238,14 @@ details. */
            timer_settime
       111: Export sigqueue, sighold.
       112: Redefine some mtget fields.
+      113: Again redefine some mtget fields.  Use mt_fileno and mt_blkno as
+           on Linux.
      */
 
      /* Note that we forgot to bump the api for ualarm, strtoll, strtoull */
 
 #define CYGWIN_VERSION_API_MAJOR 0
-#define CYGWIN_VERSION_API_MINOR 112
+#define CYGWIN_VERSION_API_MINOR 113
 
      /* There is also a compatibity version number associated with the
 	shared memory regions.  It is incremented when incompatible

winsup/cygwin/mtinfo.h

@@ -0,0 +1,133 @@
+/* mtinfo.h: Defininitions for the Cygwin tape driver class.
+
+   Copyright 2004 Red Hat, Inc.
+
+This file is part of Cygwin.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#define MTINFO_MAGIC		0x179b2af0
+#define MTINFO_VERSION		1
+
+/* Maximum number of supported partitions per drive. */
+#define MAX_PARTITION_NUM	64
+/* Maximum number of supported drives. */
+#define MAX_DRIVE_NUM		8
+
+/* Values for bookkeeping of the tape position relative to filemarks
+   and eod/eom.  */
+enum eom_val
+{
+  no_eof,
+  eof_hit,
+  eof,
+  eod_hit,
+  eod,
+  eom_hit,
+  eom
+};
+
+enum dirty_state
+{
+  clean,
+  has_read,
+  has_written
+};
+
+enum lock_state
+{
+  unlocked,
+  lock_error,
+  auto_locked,
+  locked
+};
+
+/* Partition specific information */
+class mtinfo_part
+{
+public:
+  long block;		/* logical block no */
+  long file;		/* current file no */
+  long fblock;		/* relative block no */
+  bool smark;		/* At setmark? */
+  eom_val emark;	/* "end-of"-mark */
+
+  void initialize (long nblock = -1);
+};
+
+class mtinfo_drive
+{
+  int drive;
+  int lasterr;
+  long partition;
+  long block;
+  dirty_state dirty;
+  lock_state lock;
+  TAPE_GET_DRIVE_PARAMETERS _dp;
+  TAPE_GET_MEDIA_PARAMETERS _mp;
+  bool buffer_writes;
+  bool two_fm;
+  bool fast_eom;
+  bool auto_lock;
+  bool sysv;
+  bool nowait;
+  mtinfo_part _part[MAX_PARTITION_NUM];
+
+  inline int error (const char *str)
+    {
+      if (lasterr)
+        debug_printf ("%s: Win32 error %d", lasterr);
+      return lasterr;
+    }
+  inline bool get_feature (DWORD parm)
+    {
+      return ((parm & TAPE_DRIVE_HIGH_FEATURES)
+	      ? ((_dp.FeaturesHigh & parm) != 0)
+	      : ((_dp.FeaturesLow & parm) != 0));
+    }
+  int get_pos (HANDLE mt, long *ppartition = NULL, long *pblock = NULL);
+  int _set_pos (HANDLE mt, int mode, long count, int partition);
+  int create_partitions (HANDLE mt, long count);
+  int set_partition (HANDLE mt, long count);
+  int write_marks (HANDLE mt, int marktype, DWORD count);
+  int erase (HANDLE mt, int mode);
+  int prepare (HANDLE mt, int action, bool is_auto = false);
+  int set_compression (HANDLE mt, long count);
+  int set_blocksize (HANDLE mt, long count);
+  int status (HANDLE mt, struct mtget *get);
+  int set_options (HANDLE mt, long options);
+
+public:
+  void initialize (int num, bool first_time);
+  int get_dp (HANDLE mt);
+  int get_mp (HANDLE mt);
+  int open (HANDLE mt);
+  int close (HANDLE mt, bool rewind);
+  int read (HANDLE mt, void *ptr, size_t &ulen);
+  int write (HANDLE mt, const void *ptr, size_t &len);
+  int ioctl (HANDLE mt, unsigned int cmd, void *buf);
+  int set_pos (HANDLE mt, int mode, long count, bool sfm_func);
+
+  inline bool buffered_writes (void) { return buffer_writes; }
+  PTAPE_GET_DRIVE_PARAMETERS dp (void) { return &_dp; }
+  PTAPE_GET_MEDIA_PARAMETERS mp (void) { return &_mp; }
+  mtinfo_part *part (int num) { return &_part[num]; }
+};
+
+class mtinfo
+{
+  DWORD magic;
+  DWORD version;
+  mtinfo_drive _drive[MAX_DRIVE_NUM];
+
+public:
+  void initialize (void);
+  mtinfo_drive *drive (int num) { return &_drive[num]; }
+};
+
+extern HANDLE mt_h;
+extern mtinfo *mt;
+
+extern void __stdcall mtinfo_init ();

winsup/cygwin/shared.cc

@@ -26,6 +26,7 @@ details. */
 #include "registry.h"
 #include "cygwin_version.h"
 #include "child_info.h"
+#include "mtinfo.h"
 
 shared_info NO_COPY *cygwin_shared;
 user_info NO_COPY *user_shared;
@@ -58,11 +59,17 @@ static char *offsets[] =
     + pround (sizeof (shared_info))
     + pround (sizeof (user_info))
     + pround (sizeof (console_state)),
+  (char *) cygwin_shared_address
+    + pround (sizeof (shared_info))
+    + pround (sizeof (user_info))
+    + pround (sizeof (console_state))
+    + pround (sizeof (_pinfo)),
   (char *) cygwin_shared_address
     + pround (sizeof (shared_info))
     + pround (sizeof (user_info))
     + pround (sizeof (console_state))
     + pround (sizeof (_pinfo))
+    + pround (sizeof (mtinfo))
 };
 
 void * __stdcall
@@ -243,6 +250,7 @@ memory_init ()
   ProtectHandleINH (cygheap->shared_h);
 
   user_shared_initialize (false);
+  mtinfo_init ();
 }
 
 unsigned

winsup/cygwin/shared_info.h

@@ -176,6 +176,7 @@ enum shared_locations
   SH_USER_SHARED,
   SH_SHARED_CONSOLE,
   SH_MYSELF,
+  SH_MTINFO,
   SH_TOTAL_SIZE
 };
 void __stdcall memory_init ();