static jint
receiveBytes(SharedMemoryConnection *connection, void *bytes, jint length)
{
Stream *stream = &connection->incoming;
SharedStream *shared = stream->shared;
jint fragmentStart;
jint fragmentLength;
jint index = 0;
jint maxLength;
CHECK_ERROR(enterMutex(stream, connection->shutdown));
while (index < length) {
CHECK_ERROR(waitForData(connection, stream));
SHMEM_ASSERT(!EMPTY(stream));
fragmentStart = shared->readOffset;
if (fragmentStart < shared->writeOffset) {
maxLength = shared->writeOffset - fragmentStart;
} else {
maxLength = SHARED_BUFFER_SIZE - fragmentStart;
}
fragmentLength = MIN(maxLength, length - index);
memcpy((jbyte *)bytes + index, shared->buffer + fragmentStart, fragmentLength);
shared->readOffset = ADD_OFFSET(fragmentStart, fragmentLength);
index += fragmentLength;
shared->isFull = JNI_FALSE;
STREAM_INVARIANT(stream);
CHECK_ERROR(signalSpace(stream));
}
CHECK_ERROR(leaveMutex(stream));
return SYS_OK;
}
jint
shmemBase_sendByte(SharedMemoryConnection *connection, jbyte data)
{
Stream *stream = &connection->outgoing;
SharedStream *shared = stream->shared;
int offset;
CHECK_ERROR(enterMutex(stream, connection->shutdown));
CHECK_ERROR(waitForSpace(connection, stream));
SHMEM_ASSERT(!FULL(stream));
offset = shared->writeOffset;
shared->buffer[offset] = data;
shared->writeOffset = ADD_OFFSET(offset, 1);
shared->isFull = (shared->readOffset == shared->writeOffset);
STREAM_INVARIANT(stream);
CHECK_ERROR(leaveMutex(stream));
CHECK_ERROR(signalData(stream));
return SYS_OK;
}
jint
shmemBase_receiveByte(SharedMemoryConnection *connection, jbyte *data)
{
Stream *stream = &connection->incoming;
SharedStream *shared = stream->shared;
int offset;
CHECK_ERROR(enterMutex(stream, connection->shutdown));
CHECK_ERROR(waitForData(connection, stream));
SHMEM_ASSERT(!EMPTY(stream));
offset = shared->readOffset;
*data = shared->buffer[offset];
shared->readOffset = ADD_OFFSET(offset, 1);
shared->isFull = JNI_FALSE;
STREAM_INVARIANT(stream);
CHECK_ERROR(leaveMutex(stream));
CHECK_ERROR(signalSpace(stream));
return SYS_OK;
}
static jint
sendBytes(SharedMemoryConnection *connection, const void *bytes, jint length)
{
Stream *stream = &connection->outgoing;
SharedStream *shared = stream->shared;
jint fragmentStart;
jint fragmentLength;
jint index = 0;
jint maxLength;
clearLastError();
CHECK_ERROR(enterMutex(stream, connection->shutdown));
while (index < length) {
CHECK_ERROR(waitForSpace(connection, stream));
SHMEM_ASSERT(!FULL(stream));
fragmentStart = shared->writeOffset;
if (fragmentStart < shared->readOffset) {
maxLength = shared->readOffset - fragmentStart;
} else {
maxLength = SHARED_BUFFER_SIZE - fragmentStart;
}
fragmentLength = MIN(maxLength, length - index);
memcpy(shared->buffer + fragmentStart, (jbyte *)bytes + index, fragmentLength);
shared->writeOffset = ADD_OFFSET(fragmentStart, fragmentLength);
index += fragmentLength;
shared->isFull = (shared->readOffset == shared->writeOffset);
STREAM_INVARIANT(stream);
CHECK_ERROR(signalData(stream));
}
CHECK_ERROR(leaveMutex(stream));
return SYS_OK;
}