* fhandler_raw.cc (fhandler_dev_raw::raw_read): When reading with

	variable block size, read only one block, read directly into user
	supplied buffer, return ENOMEM if user supplied buffer is smaller
	than size of next block to read.  Use read2 instead of bytes_to_read
	to count number of bytes read.
	* fhandler_tape.cc (fhandler_dev_tape::open): Add debug output.

1 files changed, 26 insertions, 11 deletions

diff --git a/winsup/cygwin/fhandler_raw.cc b/winsup/cygwin/fhandler_raw.cc
index afa478b7f..8baa6ae09 100644
--- a/winsup/cygwin/fhandler_raw.cc
+++ b/winsup/cygwin/fhandler_raw.cc
@@ -275,21 +275,29 @@ fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
 		  tgt = (char *) ptr;
 		  debug_printf ("read %d bytes direct from file",bytes_to_read);
 		}
+	      else if (varblkop)
+		{
+		  tgt = (char *) ptr;
+		  bytes_to_read = len;
+		  debug_printf ("read variable bytes direct from file");
+		}
 	      else
 		{
-		  bytes_to_read = devbufsiz;
 		  tgt = devbuf;
-		  if (varblkop)
-		    debug_printf ("read variable bytes from file into buffer");
-		  else
-		    debug_printf ("read %d bytes from file into buffer",
-				  bytes_to_read);
+		  bytes_to_read = devbufsiz;
+		  debug_printf ("read %d bytes from file into buffer",
+				bytes_to_read);
 		}
 	      if (!read_file (get_handle (), tgt, bytes_to_read, &read2, &ret))
 		{
 		  if (!is_eof (ret) && !is_eom (ret))
 		    {
-		      __seterrno ();
+		      if (varblkop && ret == ERROR_MORE_DATA)
+		        /* *ulen < blocksize.  Linux returns ENOMEM here
+			   when reading with variable blocksize . */
+		        set_errno (ENOMEM);
+		      else
+			__seterrno ();
 		      goto err;
 		    }
 
@@ -310,18 +318,25 @@ fhandler_dev_raw::raw_read (void *ptr, size_t& ulen)
 		    }
 		  lastblk_to_read = 1;
 		}
-	      if (! read2)
+	      if (!read2)
 	       break;
 	      if (tgt == devbuf)
 		{
 		  devbufstart = 0;
 		  devbufend = read2;
 		}
+	      else if (varblkop)
+		{
+		  /* When reading tapes with variable block size, we
+		     leave right after reading one block. */
+		  bytes_read = read2;
+		  break;
+		}
 	      else
 		{
-		  len -= bytes_to_read;
-		  ptr = (void *) ((char *) ptr + bytes_to_read);
-		  bytes_read += bytes_to_read;
+		  len -= read2;
+		  ptr = (void *) ((char *) ptr + read2);
+		  bytes_read += read2;
 		}
 	    }
 	}