https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=995d2a824a8faf71ef91eb8b7a7b3054209565d8

commit 995d2a824a8faf71ef91eb8b7a7b3054209565d8
Author: Corinna Vinschen <[email protected]>
Date:   Fri Jun 29 15:29:36 2018 +0200

    Cygwin: tape: Handle non-standard "no medium" error code
    
    Certain tape drives (known example: QUANTUM_ULTRIUM-HH6) return
    the non-standard ERROR_NOT_READY rather than ERROR_NO_MEDIA_IN_DRIVE
    if no media is present.  ERROR_NOT_READY is not documented as valid
    return code from GetTapeStatus.  Without handling this error code
    Cygwin's tape code can't report an offline state to user space.
    
    Fix this by converting ERROR_NOT_READY to ERROR_NO_MEDIA_IN_DRIVE
    where appropriate.
    
    Add a debug_printf to mtinfo_drive::get_status to allow requesting
    user info without having to rebuild the DLL.
    
    Signed-off-by: Corinna Vinschen <[email protected]>

Diff:
---
 winsup/cygwin/fhandler_tape.cc | 27 ++++++++++++++++++++++-----
 winsup/cygwin/release/2.11.0   |  4 ++++
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/winsup/cygwin/fhandler_tape.cc b/winsup/cygwin/fhandler_tape.cc
index 9cfa2bb..a7f64ea 100644
--- a/winsup/cygwin/fhandler_tape.cc
+++ b/winsup/cygwin/fhandler_tape.cc
@@ -32,6 +32,16 @@ details. */
                            part (partition)->initialize (0); \
                          }
 
+/* Certain tape drives (known example: QUANTUM_ULTRIUM-HH6) return
+   ERROR_NOT_READY rather than ERROR_NO_MEDIA_IN_DRIVE if no media
+   is in the drive.  Convert this to the only sane error code. */
+#define GET_TAPE_STATUS(_h) ({ \
+                               int _err = GetTapeStatus (_h); \
+                               if (_err == ERROR_NOT_READY) \
+                                 _err = ERROR_NO_MEDIA_IN_DRIVE; \
+                               _err; \
+                          })
+
 #define IS_BOT(err) ((err) == ERROR_BEGINNING_OF_MEDIA)
 
 #define IS_EOF(err) ((err) == ERROR_FILEMARK_DETECTED \
@@ -98,6 +108,9 @@ mtinfo_drive::get_mp (HANDLE mt)
 {
   DWORD len = sizeof _mp;
   TAPE_FUNC (GetTapeParameters (mt, GET_TAPE_MEDIA_INFORMATION, &len, &_mp));
+  /* See GET_TAPE_STATUS comment. */
+  if (lasterr == ERROR_NOT_READY)
+    lasterr = ERROR_NO_MEDIA_IN_DRIVE;
   return error ("get_mp");
 }
 
@@ -130,7 +143,7 @@ int
 mtinfo_drive::close (HANDLE mt, bool rewind)
 {
   lasterr = 0;
-  if (GetTapeStatus (mt) == ERROR_NO_MEDIA_IN_DRIVE)
+  if (GET_TAPE_STATUS (mt) == ERROR_NO_MEDIA_IN_DRIVE)
     dirty = clean;
   if (dirty >= has_written)
     {
@@ -187,7 +200,7 @@ mtinfo_drive::read (HANDLE mt, LPOVERLAPPED pov, void *ptr, 
size_t &ulen)
   BOOL ret;
   DWORD bytes_read = 0;
 
-  if (GetTapeStatus (mt) == ERROR_NO_MEDIA_IN_DRIVE)
+  if (GET_TAPE_STATUS (mt) == ERROR_NO_MEDIA_IN_DRIVE)
     return lasterr = ERROR_NO_MEDIA_IN_DRIVE;
   if (lasterr == ERROR_BUS_RESET)
     {
@@ -300,7 +313,7 @@ mtinfo_drive::write (HANDLE mt, LPOVERLAPPED pov, const 
void *ptr, size_t &len)
   DWORD bytes_written = 0;
   int async_err = 0;
 
-  if (GetTapeStatus (mt) == ERROR_NO_MEDIA_IN_DRIVE)
+  if (GET_TAPE_STATUS (mt) == ERROR_NO_MEDIA_IN_DRIVE)
     return lasterr = ERROR_NO_MEDIA_IN_DRIVE;
   if (lasterr == ERROR_BUS_RESET)
     {
@@ -762,8 +775,12 @@ mtinfo_drive::get_status (HANDLE mt, struct mtget *get)
   if (!get)
     return ERROR_INVALID_PARAMETER;
 
-  if ((tstat = GetTapeStatus (mt)) == ERROR_NO_MEDIA_IN_DRIVE
-      || get_mp (mt) == ERROR_NO_MEDIA_IN_DRIVE)
+  tstat = GET_TAPE_STATUS (mt);
+  DWORD mpstat = (DWORD) get_mp (mt);
+
+  debug_printf ("GetTapeStatus: %u, get_mp: %d", tstat, mpstat);
+
+  if (tstat == ERROR_NO_MEDIA_IN_DRIVE || mpstat == ERROR_NO_MEDIA_IN_DRIVE)
     notape = 1;
 
   memset (get, 0, sizeof *get);
diff --git a/winsup/cygwin/release/2.11.0 b/winsup/cygwin/release/2.11.0
index b1aaaf3..9e73e0a 100644
--- a/winsup/cygwin/release/2.11.0
+++ b/winsup/cygwin/release/2.11.0
@@ -40,3 +40,7 @@ Bug Fixes
 
 - Fix Unicode table.
   Addresses: https://cygwin.com/ml/cygwin/2018-06/msg00248.html
+
+- Handle a non-standard return value from some tape drives to
+  report a "no-media" error.
+  Addresses: https://cygwin.com/ml/cygwin/2018-06/msg00245.html

Reply via email to