/**
* Writes from a byte array using the supplied file descriptor.
*
* @param src The source buffer.
* @return Number of bytes written.
* @throws IOException
*/
public int write(byte[] src, int pos, int len) throws IOException {
if (MemoryManager.willNeverMove(src)) {
return write(nfd.getNativeFD(), src, pos, len);
} else {
byte[] buffer;
// Rebuffer the IO in a thread-local DirectBuffer
buffer = localByteArray.get(len);
if (VM.VerifyAssertions) VM._assert(MemoryManager.willNeverMove(buffer));
System.arraycopy(src, pos, buffer, 0, len);
return write(nfd.getNativeFD(), buffer, 0, len);
}
}
/**
* Reads a byte array directly. Performs optimal buffering.
*
* <p>If the target buffer is pinned, use it directly. Otherwise allocate one of the thread-local
* buffers, perform the IO to that, and copy the result to the target array.
*
* @param dst Byte array to read to
* @return Number of bytes read.
* @throws IOException If an error occurs or dst is not a direct buffers.
*/
private int read(byte[] dst, int pos, int len) throws IOException {
if (MemoryManager.willNeverMove(dst)) {
return read(nfd.getNativeFD(), dst, pos, len);
} else {
byte[] buffer;
// Rebuffer the IO in a thread-local byte array
buffer = localByteArray.get(len);
/* perform the read */
int bytes = read(nfd.getNativeFD(), buffer, 0, len);
if (bytes > 0) System.arraycopy(buffer, 0, dst, pos, bytes);
return bytes;
}
}
