natFileDescriptorWin32.cc (setLength): New method.

2002-07-24  Tom Tromey  <tromey@redhat.com>
            Tony Kimball <alk@pobox.com>

	* java/io/natFileDescriptorWin32.cc (setLength): New method.
	* java/io/natFileDescriptorPosix.cc (setLength): New method.
	* java/io/RandomAccessFile.java (setLength): New method.
	* java/io/natFileDescriptorEcos.cc (setLength): New method.
	* java/io/FileDescriptor.java (setLength): New method.

Co-Authored-By: Tony Kimball <alk@pobox.com>

From-SVN: r55715

libjava/ChangeLog

+2002-07-24  Tom Tromey  <tromey@redhat.com>
+            Tony Kimball <alk@pobox.com>
+
+	* java/io/natFileDescriptorWin32.cc (setLength): New method.
+	* java/io/natFileDescriptorPosix.cc (setLength): New method.
+	* java/io/RandomAccessFile.java (setLength): New method.
+	* java/io/natFileDescriptorEcos.cc (setLength): New method.
+	* java/io/FileDescriptor.java (setLength): New method.
+
 2002-07-24  Mark Wielaard  <mark@klomp.org>
 
 	* java/lang/reflect/natField.cc (setAddr): Check isAccessible().

libjava/java/io/FileDescriptor.java

 // FileDescriptor.java - Open file or device
 
-/* Copyright (C) 1998, 1999, 2000, 2001  Free Software Foundation
+/* Copyright (C) 1998, 1999, 2000, 2001, 2002  Free Software Foundation
 
    This file is part of libgcj.
 
@@ -65,6 +65,7 @@ public final class FileDescriptor
   native void write (byte[] b, int offset, int len)
     throws IOException, NullPointerException, IndexOutOfBoundsException;
   native void close () throws IOException;
+  native void setLength (long pos) throws IOException;
   // EOF_TRUNC is true if a request to seek past the end of file
   // should actually stop at the end of file.  If false, then a seek
   // past the end is ok (and if a subsequent write occurs the file

libjava/java/io/RandomAccessFile.java

 // RandomAccessFile.java
 
-/* Copyright (C) 1998, 1999, 2001  Free Software Foundation
+/* Copyright (C) 1998, 1999, 2001, 2002  Free Software Foundation
 
    This file is part of libgcj.
 
@@ -40,6 +40,11 @@ public class RandomAccessFile implements DataOutput, DataInput
     return fd.getFilePointer();
   }
 
+  public void setLength (long pos) throws IOException
+  {
+    fd.setLength(pos);
+  }
+
   public long length () throws IOException
   {
     return fd.length();

libjava/java/io/natFileDescriptorEcos.cc

@@ -95,6 +95,11 @@ java::io::FileDescriptor::close (void)
 {
 }
 
+void
+java::io::FileDescriptor::setLength (long)
+{
+}
+
 jint
 java::io::FileDescriptor::seek (jlong pos, jint whence, jboolean)
 {

libjava/java/io/natFileDescriptorPosix.cc

@@ -17,6 +17,8 @@ details.  */
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/param.h>
+#include <sys/socket.h>
+#include <fcntl.h>
 
 #ifdef HAVE_SYS_IOCTL_H
 #define BSD_COMP /* Get FIONREAD on Solaris2. */
@@ -189,6 +191,38 @@ java::io::FileDescriptor::close (void)
     throw new IOException (JvNewStringLatin1 (strerror (errno)));
 }
 
+void
+java::io::FileDescriptor::setLength (jlong pos)
+{
+  struct stat sb;
+  off_t orig;
+
+  if (::fstat (fd, &sb))
+    throw new IOException (JvNewStringLatin1 (strerror (errno)));
+
+  if ((jlong) sb.st_size == pos) 
+    return;
+
+  orig = ::lseek (fd, (off_t) 0, SEEK_CUR);
+  if (orig == -1)
+    throw new IOException (JvNewStringLatin1 (strerror (errno)));
+
+  // If the file is too short, we extend it.  We can't rely on
+  // ftruncate() extending the file.  So we lseek() to 1 byte less
+  // than we want, and then we write a single byte at the end.
+  if ((jlong) sb.st_size < pos)
+    {
+      if (::lseek (fd, (off_t) (pos - 1), SEEK_SET) == -1)
+	throw new IOException (JvNewStringLatin1 (strerror (errno)));
+      char out = '\0';
+      int r = ::write (fd, &out, 1);
+      if (r <= 0 || ::lseek (fd, orig, SEEK_SET) == -1)
+	throw new IOException (JvNewStringLatin1 (strerror (errno)));
+    }
+  else if (::ftruncate (fd, (off_t) pos))
+    throw new IOException (JvNewStringLatin1 (strerror (errno)));
+}
+
 jint
 java::io::FileDescriptor::seek (jlong pos, jint whence, jboolean eof_trunc)
 {

libjava/java/io/natFileDescriptorWin32.cc

 // natFileDescriptorWin32.cc - Native part of FileDescriptor class.
 
-/* Copyright (C) 1998, 1999, 2000, 2001  Free Software Foundation, Inc.
+/* Copyright (C) 1998, 1999, 2000, 2001, 2002  Free Software Foundation, Inc.
 
    This file is part of libgcj.
 
@@ -186,6 +186,58 @@ java::io::FileDescriptor::close (void)
     throw new IOException (JvNewStringLatin1 (winerr ()));
 }
 
+void
+java::io::FileDescriptor::setLength(jlong pos)
+{
+  LONG liOrigFilePointer;
+  LONG liNewFilePointer;
+  LONG liEndFilePointer;
+
+  // Get the original file pointer.
+  if (SetFilePointer((HANDLE) fd, (LONG) 0, &liOrigFilePointer,
+		     FILE_CURRENT) != (BOOL) 0
+      && (GetLastError() != NO_ERROR))
+    throw new IOException (JvNewStringLatin1 (winerr ()));
+
+  // Get the length of the file.
+  if (SetFilePointer((HANDLE) fd, (LONG) 0, &liEndFilePointer,
+		     FILE_END) != (BOOL) 0
+      && (GetLastError() != NO_ERROR))
+    throw new IOException (JvNewStringLatin1 (winerr ()));
+
+  if ((jlong)liEndFilePointer == pos)
+    {
+      // Restore the file pointer.
+      if (liOrigFilePointer != liEndFilePointer)
+	{
+	  if (SetFilePointer((HANDLE) fd, liOrigFilePointer, &liNewFilePointer,
+			     FILE_BEGIN) != (BOOL) 0
+	      && (GetLastError() != NO_ERROR))
+	    throw new IOException (JvNewStringLatin1 (winerr ()));
+	}
+      return;
+    }
+
+  // Seek to the new end of file.
+  if (SetFilePointer((HANDLE) fd, (LONG) pos, &liNewFilePointer,
+		     FILE_BEGIN) != (BOOL) 0
+      && (GetLastError() != NO_ERROR))
+    throw new IOException (JvNewStringLatin1 (winerr ()));
+
+  // Truncate the file at this point.
+  if (SetEndOfFile((HANDLE) fd) != (BOOL) 0 && (GetLastError() != NO_ERROR))
+    throw new IOException (JvNewStringLatin1 (winerr ()));
+
+  if (liOrigFilePointer < liNewFilePointer)
+    {
+      // Restore the file pointer.
+      if (SetFilePointer((HANDLE) fd, liOrigFilePointer, &liNewFilePointer,
+			 FILE_BEGIN) != (BOOL) 0
+	  && (GetLastError() != NO_ERROR))
+	throw new IOException (JvNewStringLatin1 (winerr ()));
+    }
+}
+
 jint
 java::io::FileDescriptor::seek (jlong pos, jint whence, jboolean eof_trunc)
 {