Fixed several append issues:

- FileChannelImpl.truncate() should not attempt to seek (would throw an exception)
- FileDispatcherImpl.write() doesn't need to seek to EOF
- FileDispatcherImpl.truncate() can't use fd.setLength() to truncate on append FileStream, so we open the file again to truncate it
- NetFileSystemProvider.newFileChannel() should not set FileSystemRights.Write in append mode

3 files changed, 31 insertions, 10 deletions

diff --git a/openjdk/sun/nio/ch/FileChannelImpl.java b/openjdk/sun/nio/ch/FileChannelImpl.java
index 86049d69..160e1f54 100644
--- a/openjdk/sun/nio/ch/FileChannelImpl.java
+++ b/openjdk/sun/nio/ch/FileChannelImpl.java
@@ -343,6 +343,10 @@ public class FileChannelImpl
                 if (!isOpen())
                     return null;
 
+                // [IKVM] in append mode we're not allowed to seek backwards, but the atomic append will honor the new file size
+                if (append)
+                    return this;
+
                 // set position to size if greater than size
                 if (p > size)
                     p = size;
diff --git a/openjdk/sun/nio/ch/FileDispatcherImpl.java b/openjdk/sun/nio/ch/FileDispatcherImpl.java
index e8d4a55b..9d836dfd 100644
--- a/openjdk/sun/nio/ch/FileDispatcherImpl.java
+++ b/openjdk/sun/nio/ch/FileDispatcherImpl.java
@@ -56,9 +56,6 @@ class FileDispatcherImpl extends FileDispatcher
     }
 
     int write(FileDescriptor fd, byte[] buf, int offset, int length) throws IOException {
-        if (append) {
-            fd.seek(fd.length());
-        }
         fd.writeBytes(buf, offset, length);
         return length;
     }
@@ -129,7 +126,14 @@ class FileDispatcherImpl extends FileDispatcher
     }
 
     int truncate(FileDescriptor fd, long size) throws IOException {
-        fd.setLength(size);
+        if (append) {
+            // HACK in append mode we're not allowed to truncate, so we try to reopen the file and truncate that
+            try (FileOutputStream fos = new FileOutputStream(((FileStream)fd.getStream()).get_Name())) {
+                fos.getFD().setLength(size);
+            }
+        } else {
+            fd.setLength(size);
+        }
         return 0;
     }
 
diff --git a/openjdk/sun/nio/fs/NetFileSystemProvider.java b/openjdk/sun/nio/fs/NetFileSystemProvider.java
index 19ee8fc7..0188273a 100644
--- a/openjdk/sun/nio/fs/NetFileSystemProvider.java
+++ b/openjdk/sun/nio/fs/NetFileSystemProvider.java
@@ -80,7 +80,6 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
             throw new NotYetImplementedError();
         }
         int mode = FileMode.Open;
-        int rights = 0;
         int share = FileShare.ReadWrite | FileShare.Delete;
         int options = FileOptions.None;
         boolean read = false;
@@ -97,7 +96,6 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
                         append = true;
                         write = true;
                         mode = FileMode.Append;
-                        rights |= FileSystemRights.AppendData;
                         break;
                     case CREATE:
                         mode = FileMode.Create;
@@ -113,7 +111,6 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
                         break;
                     case READ:
                         read = true;
-                        rights |= FileSystemRights.Read;
                         break;
                     case SPARSE:
                         sparse = true;
@@ -126,7 +123,6 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
                         break;
                     case WRITE:
                         write = true;
-                        rights |= FileSystemRights.Write;
                         break;
                     default:
                         throw new UnsupportedOperationException();
@@ -162,7 +158,6 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
         if (!read && !write)
         {
             read = true;
-            rights |= FileSystemRights.Read;
         }
 
         if (read && append)
@@ -179,7 +174,25 @@ final class NetFileSystemProvider extends AbstractFileSystemProvider
         {
             throw new UnsupportedOperationException();
         }
-        
+
+        int rights = 0;
+        if (append)
+        {
+            // for atomic append to work, we can't set FileSystemRights.Write
+            rights |= FileSystemRights.AppendData;
+        }
+        else
+        {
+            if (read)
+            {
+                rights |= FileSystemRights.Read;
+            }
+            if (write)
+            {
+                rights |= FileSystemRights.Write;
+            }
+        }
+
         FileStream fs;
         try
         {