static int
writePacket (
BrailleDisplay *brl,
unsigned char type,
unsigned char arg1,
unsigned char arg2,
unsigned char arg3,
const unsigned char *data
) {
FS_Packet packet;
int size = sizeof(packet.header);
unsigned char checksum = 0;
checksum -= (packet.header.type = type);
checksum -= (packet.header.arg1 = arg1);
checksum -= (packet.header.arg2 = arg2);
checksum -= (packet.header.arg3 = arg3);
if (data) {
unsigned char length = packet.header.arg1;
int index;
for (index=0; index<length; index+=1)
checksum -= (packet.payload.bytes[index] = data[index]);
packet.payload.bytes[length] = checksum;
size += length + 1;
}
return writeBraillePacket(brl, NULL, &packet, size);
}
static int
writePacket (BrailleDisplay *brl, unsigned char type, unsigned char length, const void *data) {
HW_Packet packet;
packet.fields.header = ESC;
packet.fields.type = type;
packet.fields.length = length;
memcpy(packet.fields.data.bytes, data, length);
length += packet.fields.data.bytes - packet.bytes;
return writeBraillePacket(brl, brl->data->gioEndpoint, &packet, length);
}
static int
writePacket (BrailleDisplay *brl, const unsigned char *packet, int size) {
unsigned char buffer[1 + (size * 2)];
unsigned char *byte = buffer;
*byte++ = BN_REQ_BEGIN;
while (size > 0) {
if ((*byte++ = *packet++) == BN_REQ_BEGIN) *byte++ = BN_REQ_BEGIN;
--size;
}
return writeBraillePacket(brl, NULL, buffer, byte-buffer);
}
static int
writeSerialPacket (BrailleDisplay *brl, unsigned char code, unsigned char *data, unsigned char count) {
unsigned char buffer[2 + (count * 2)];
unsigned char size = 0;
unsigned char index;
buffer[size++] = ESC;
buffer[size++] = code;
for (index=0; index<count; ++index)
if ((buffer[size++] = data[index]) == buffer[0])
buffer[size++] = buffer[0];
return writeBraillePacket(brl, NULL, buffer, size);
}
static int
writeBytes (BrailleDisplay *brl, const unsigned char *bytes, size_t count) {
return writeBraillePacket(brl, NULL, bytes, count);
}
static int
writeBytes (BrailleDisplay *brl, const unsigned char *bytes, size_t count) {
return writeBraillePacket(brl, brl->data->gioEndpoint, bytes, count);
}
static int
writePacket (BrailleDisplay *brl, const void *packet, size_t size) {
return writeBraillePacket(brl, gioEndpoint, packet, size);
}
static int
writePacket (
BrailleDisplay *brl,
unsigned char type, unsigned char mode,
const unsigned char *data1, size_t length1,
const unsigned char *data2, size_t length2
) {
unsigned char packet[2 + 1 + 1 + 2 + length1 + 1 + 1 + 2 + length2 + 1 + 4 + 1 + 2];
unsigned char *byte = packet;
unsigned char *checksum;
/* DS */
*byte++ = type;
*byte++ = type;
/* M */
*byte++ = mode;
/* DS1 */
*byte++ = 0XF0;
/* Cnt1 */
*byte++ = (length1 >> 0) & 0XFF;
*byte++ = (length1 >> 8) & 0XFF;
/* D1 */
byte = mempcpy(byte, data1, length1);
/* DE1 */
*byte++ = 0XF1;
/* DS2 */
*byte++ = 0XF2;
/* Cnt2 */
*byte++ = (length2 >> 0) & 0XFF;
*byte++ = (length2 >> 8) & 0XFF;
/* D2 */
byte = mempcpy(byte, data2, length2);
/* DE2 */
*byte++ = 0XF3;
/* Reserved */
{
int count = 4;
while (count--) *byte++ = 0;
}
/* Chk */
*(checksum = byte++) = 0;
/* DE */
*byte++ = 0XFD;
*byte++ = 0XFD;
{
unsigned char sum = 0;
const unsigned char *ptr = packet;
while (ptr != byte) sum += *ptr++;
*checksum = sum;
}
return writeBraillePacket(brl, brl->data->gioEndpoint, packet, byte - packet);
}