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 * except in compliance with the License. You may obtain a copy of
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 *
 * Software distributed under the License is distributed on an "AS
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package org.jruby.ext.ffi.io;

import org.jruby.Ruby;
import org.jruby.RubyClass;
import org.jruby.RubyIO;
import org.jruby.RubyModule;
import org.jruby.RubyNumeric;
import org.jruby.anno.JRubyClass;
import org.jruby.anno.JRubyMethod;
import org.jruby.runtime.ObjectAllocator;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.util.io.BadDescriptorException;
import org.jruby.util.io.ChannelDescriptor;
import org.jruby.util.io.ChannelStream;
import org.jruby.util.io.ModeFlags;

/**
 * An IO implementation that reads/writes to a native file descriptor.
 */
@JRubyClass(name="FFI::" + FileDescriptorIO.CLASS_NAME, parent="IO")
public class FileDescriptorIO extends RubyIO {
    public static final String CLASS_NAME = "FileDescriptorIO";
    private static final class Allocator implements ObjectAllocator {
        public final IRubyObject allocate(Ruby runtime, RubyClass klass) {
            return new FileDescriptorIO(runtime, klass);
        }
        private static final ObjectAllocator INSTANCE = new Allocator();
    }
    public FileDescriptorIO(Ruby runtime, RubyClass klass) {
        super(runtime, klass);
    }
    public FileDescriptorIO(Ruby runtime, IRubyObject fd) {
        super(runtime, runtime.getModule("FFI").getClass(CLASS_NAME));
        ModeFlags modes;
        try {
            modes = newModeFlags(runtime, ModeFlags.RDWR);
            openFile.setMainStream(ChannelStream.open(getRuntime(),
                    new ChannelDescriptor(new FileDescriptorByteChannel(getRuntime(), RubyNumeric.fix2int(fd)),
                    modes)));
            openFile.setPipeStream(openFile.getMainStreamSafe());
            openFile.setMode(modes.getOpenFileFlags());
            openFile.getMainStreamSafe().setSync(true);
        } catch (BadDescriptorException e) {
            throw runtime.newErrnoEBADFError();
        }
    }
    public static RubyClass createFileDescriptorIOClass(Ruby runtime, RubyModule module) {
        RubyClass result = runtime.defineClassUnder(CLASS_NAME, runtime.getClass("IO"),
                Allocator.INSTANCE, module);
        result.defineAnnotatedMethods(FileDescriptorIO.class);
        result.defineAnnotatedConstants(FileDescriptorIO.class);

        return result;
    }
    @JRubyMethod(name = "new", meta = true)
    public static FileDescriptorIO newInstance(ThreadContext context, IRubyObject recv, IRubyObject fd) {
        return new FileDescriptorIO(context.getRuntime(), fd);
    }
    @JRubyMethod(name = "wrap", required = 1, meta = true)
    public static RubyIO wrap(ThreadContext context, IRubyObject recv, IRubyObject fd) {
        return new FileDescriptorIO(context.getRuntime(), fd);
    }
}
