/** @inheritDoc */
public int writeBuf(int fd, byte buffer[], int off, int len) throws IOException {
int result = 0;
byte[] buf = buffer;
if (off != 0) {
buf = new byte[len];
System.arraycopy(buffer, off, buf, 0, len);
}
if (DEBUG) {
System.err.println("writeBuf(" + fd + ") before write.");
}
result = libc.write(fd, buf, len); // We rely on open0() for setting the socket to non-blocking
if (result < 0) {
int err_code = LibCUtil.errno();
if (err_code == LibC.EWOULDBLOCK) {
VMThread.getSystemEvents().waitForWriteEvent(fd);
if (DEBUG) {
System.err.println("writeBuf(" + fd + ") returned from select. retry.");
}
result =
libc.write(fd, buf, len); // We rely on open0() for setting the socket to non-blocking
}
if (DEBUG) {
System.err.println("writeBuf(" + fd + ") error:");
}
LibCUtil.errCheckNeg(result);
}
return result;
}
/** @inheritDoc */
public void close(int fd) throws IOException {
// NOTE: this would block the VM. A real implementation should
// make this a async native method.
sockets.shutdown(fd, 2);
libc.close(fd);
if (DEBUG) {
System.out.println("close(" + fd + ")");
}
}
private void set_blocking_flags(int fd, boolean is_blocking) throws IOException {
if (tryFcntl) {
int flags = libc.fcntl(fd, LibC.F_GETFL, 0);
if (DEBUG) {
System.out.println("set_blocking_flags: fcntl F_GETFL = " + flags);
}
if (flags >= 0) {
if (is_blocking == true) {
flags &= ~LibC.O_NONBLOCK;
} else {
flags |= LibC.O_NONBLOCK;
}
if (DEBUG) {
System.out.println("set_blocking_flags: calling fcntl F_SETFL flags: " + flags);
}
int res = libc.fcntl(fd, LibC.F_SETFL, flags);
if (res != -1) {
return;
}
} else if (LibCUtil.errno() == LibC.EOPNOTSUPP) {
tryFcntl = false; // once this fails, don't try again
}
}
if (!tryFcntl) {
if (DEBUG) {
System.out.println("set_blocking_flags: calling ioctl FIONBIO = " + !is_blocking);
}
IntByReference setting =
new IntByReference(is_blocking ? 0 : 1); /* if "is_blocking"==true, NBIO = FALSE */
int res = ioctl.ioctl(fd, Ioctl.FIONBIO, setting);
setting.free();
if (DEBUG) {
System.out.println("set_blocking_flags: ioctl returned: " + res);
}
if (res >= 0) {
return;
}
}
throw newError(fd, "set_blocking_flags");
}
/** Read errno, try to clean up fd, and create exception. */
private IOException newError(int fd, String msg) {
if (DEBUG) {
VM.print(msg);
VM.print(": errno: ");
}
int err_code = LibCUtil.errno();
if (DEBUG) {
VM.print(err_code);
VM.println();
}
sockets.shutdown(fd, 2);
libc.close(fd);
return new IOException(" errno: " + err_code + " on fd: " + fd + " during " + msg);
}
/** @inheritDoc */
public int readBuf(int fd, byte b[], int offset, int length) throws IOException {
byte[] buf = b;
int result;
if (offset != 0) {
if (DEBUG) {
System.err.println("readBuf() into temp buf");
}
buf = new byte[length];
}
if (NBIO_WORKS) {
result =
libc.read(fd, buf, length); // We rely on open0() for setting the socket to non-blocking
if (result < 0) {
int err_code = LibCUtil.errno();
if (err_code == LibC.EWOULDBLOCK) {
if (DEBUG) {
System.err.println("Wait for read in select...");
}
VMThread.getSystemEvents().waitForReadEvent(fd);
result =
libc.read(
fd, buf, length); // We rely on open0() for setting the socket to non-blocking
}
LibCUtil.errCheckNeg(result);
}
} else {
// If non-blocking IO doesn't seems to be working, try this hack...
int bAvail = available(fd); // may throw IOException
if (bAvail == 0) {
if (DEBUG) {
System.err.println("Wait for read in select...");
}
VMThread.getSystemEvents().waitForReadEvent(fd);
bAvail = available(fd);
if (bAvail == 0) { // woke up because connection is closed
if (DEBUG) {
System.err.println("readBuf(" + fd + ") signalling EOF.");
}
return -1; // signal EOF
}
}
if (DEBUG) {
System.err.println("readBuf(" + fd + ") returned from select. retry.");
}
int n = Math.min(bAvail, length); // don't read more than is asked for...
result = libc.read(fd, buf, n); // only read what we know is there...
LibCUtil.errCheckNeg(result);
}
if (result == 0) {
// If remote side has shut down the connection gracefully, and all
// data has been received, recv() will complete immediately with
// zero bytes received.
//
// This is true for Win32/CE and Linux
if (DEBUG) {
System.err.println("readBuf(" + fd + ") saw remote side shutdown.");
}
result = -1;
}
if (offset != 0 && result > 0) {
System.arraycopy(buf, 0, b, offset, result);
}
if (DEBUG) {
System.out.println("readBuf(" + fd + ") = " + result);
}
return result;
}