static unsigned char
getByte (BrailleDisplay *brl) {
unsigned char byte;
while (!gioAwaitInput(brl->gioEndpoint, 1000000000));
gioReadByte(brl->gioEndpoint, &byte, 0);
return byte;
}
static unsigned char
getByte (void) {
unsigned char byte;
while (!gioAwaitInput(gioEndpoint, 1000000000));
gioReadByte(gioEndpoint, &byte, 0);
return byte;
}
unsigned char serialAvailable(
GioEndpoint *gioEndpoint){
#ifdef ARDUINO
return Serial.available();
#endif
#ifdef BRLTTY
return gioAwaitInput(gioEndpoint,0);
#endif
}
int
probeBrailleDisplay (
BrailleDisplay *brl, unsigned int retryLimit,
GioEndpoint *endpoint, int inputTimeout,
BrailleRequestWriter *writeRequest,
BraillePacketReader *readPacket, void *responsePacket, size_t responseSize,
BrailleResponseHandler *handleResponse
) {
unsigned int retryCount = 0;
if (!endpoint) endpoint = brl->gioEndpoint;
while (writeRequest(brl)) {
drainBrailleOutput(brl, 0);
while (gioAwaitInput(endpoint, inputTimeout)) {
size_t size = readPacket(brl, responsePacket, responseSize);
if (!size) break;
{
BrailleResponseResult result = handleResponse(brl, responsePacket, size);
switch (result) {
case BRL_RSP_DONE:
return 1;
case BRL_RSP_UNEXPECTED:
logUnexpectedPacket(responsePacket, size);
case BRL_RSP_CONTINUE:
break;
default:
logMessage(LOG_WARNING, "unimplemented braille response result: %u", result);
case BRL_RSP_FAIL:
return 0;
}
}
}
if (errno != EAGAIN)
#ifdef ETIMEDOUT
if (errno != ETIMEDOUT)
#endif /* ETIMEDOUT */
break;
if (retryCount == retryLimit) break;
retryCount += 1;
}
return 0;
}
static int
nextSerialPacket (unsigned char code, unsigned char *buffer, int size, int wait) {
int length;
if (wait)
if (!gioAwaitInput(gioEndpoint, SERIAL_WAIT_TIMEOUT))
return 0;
while ((length = readSerialPacket(buffer, size))) {
if (buffer[0] == code) return length;
logUnexpectedPacket(buffer, length);
}
return 0;
}
static int
startDisplayMode (BrailleDisplay *brl) {
static const unsigned char data[] = {MM_BLINK_NO, 0};
if (writePacket(brl, MM_CMD_StartDisplayMode, 0, data, sizeof(data))) {
if (gioAwaitInput(brl->gioEndpoint, START_INPUT_TIMEOUT)) {
MM_CommandPacket response;
size_t size = readPacket(brl, &response);
if (size) {
if (response.fields.header.id1 == MM_HEADER_ACK) return 1;
logUnexpectedPacket(response.bytes, size);
}
}
}
return 0;
}
static int
getSyncBrailleCellCount (BrailleDisplay *brl, unsigned int *count) {
static const unsigned char data[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
if (writePacket(brl, 0XFB, 0X01, data, sizeof(data), NULL, 0)) {
InputPacket packet;
while (gioAwaitInput(brl->data->gioEndpoint, 1000)) {
if (readPacket(brl, &packet)) {
if (packet.data.type == IPT_CELLS) {
*count = packet.data.data;
return 1;
}
}
}
}
return 0;
}
static int
readPacket (BrailleDisplay *brl, Packet *packet) {
while (1) {
int size = sizeof(PacketHeader);
int hasPayload = 0;
if (brl->data->inputCount >= sizeof(PacketHeader)) {
if (brl->data->inputBuffer.packet.header.type & 0X80) {
hasPayload = 1;
size += brl->data->inputBuffer.packet.header.arg1 + 1;
}
}
if (size <= brl->data->inputCount) {
logInputPacket(brl->data->inputBuffer.bytes, size);
if (hasPayload) {
unsigned char checksum = 0;
int index;
for (index=0; index<size; index+=1)
checksum -= brl->data->inputBuffer.bytes[index];
if (checksum) logMessage(LOG_WARNING, "Input packet checksum error.");
}
memcpy(packet, &brl->data->inputBuffer, size);
memmove(&brl->data->inputBuffer.bytes[0], &brl->data->inputBuffer.bytes[size],
brl->data->inputCount -= size);
return size;
}
retry:
{
int count = gioReadData(brl->data->gioEndpoint,
&brl->data->inputBuffer.bytes[brl->data->inputCount],
size - brl->data->inputCount,
0);
if (count < 1) {
if (count == -1) {
logSystemError("read");
} else if ((count == 0) && (brl->data->inputCount > 0)) {
if (gioAwaitInput(brl->data->gioEndpoint, 1000)) goto retry;
if (errno != EAGAIN) count = -1;
logPartialPacket(brl->data->inputBuffer.bytes, brl->data->inputCount);
brl->data->inputCount = 0;
}
return count;
}
brl->data->acknowledgementsMissing = 0;
if (!brl->data->inputCount) {
static const unsigned char packets[] = {
PKT_ACK, PKT_NAK,
PKT_KEY, PKT_EXTKEY, PKT_BUTTON, PKT_WHEEL,
PKT_INFO
};
int first;
for (first=0; first<count; first+=1)
if (memchr(packets, brl->data->inputBuffer.bytes[first], sizeof(packets)))
break;
if (first) {
logDiscardedBytes(brl->data->inputBuffer.bytes, first);
memmove(&brl->data->inputBuffer.bytes[0], &brl->data->inputBuffer.bytes[first], count-=first);
}
}
brl->data->inputCount += count;
}
}
}
