Implement tabby_printer_packet_recv() and tabby_printer_response_send()

This commit is contained in:
XANTRONIX Development 2016-05-29 14:21:16 -05:00
parent c66bfade8f
commit c675fc1f54
4 changed files with 169 additions and 293 deletions

View file

@ -6,6 +6,7 @@
#include <errno.h>
#include <tabby/link.h>
#include <tabby/printer.h>
static void usage(int argc, char **argv, char *message, ...) {
if (message) {
@ -23,18 +24,12 @@ static void usage(int argc, char **argv, char *message, ...) {
}
int main(int argc, char **argv) {
int fd;
ssize_t len;
int fd, status;
uint8_t state = 0,
value = 0,
compression = 0,
dataLengthLSB = 0,
dataLengthMSB = 0,
acknowledgeCode = 129,
statusCode = 0;
tabby_printer_packet_header header;
tabby_printer_packet_footer footer;
uint16_t dataPosition = 0;
uint8_t body[TABBY_PRINTER_MAX_PACKET_SIZE];
if (argc != 2) {
usage(argc, argv, "No device specified");
@ -47,291 +42,17 @@ int main(int argc, char **argv) {
goto error_link_open;
}
while ((len = tabby_link_recv(fd, &value, 1)) >= 0) {
uint8_t response = 0;
while (1) {
status = tabby_printer_packet_recv(fd, &header, &body, &footer);
fprintf(stderr, "state %d recv 0x%02x\n", state, value);
if (status < 0) {
fprintf(stderr, "%s: %s: %s\n",
argv[0], "tabby_printer_packet_recv()", strerror(errno));
switch (state) {
case 0: {
if (value == 136) {
state = 1;
continue;
}
response = 0;
break;
}
case 1: {
if (value == 51) {
state = 2;
response = 0;
} else {
state = 0;
response = 0;
}
break;
}
case 2: {
if (value == 1) {
state = 3;
response = 0;
compression = 0;
dataLengthLSB = 0;
dataLengthMSB = 0;
} else if (value == 2) {
state = 50;
response = 0;
} else if (value == 4) {
state = 20;
response = 0;
} else if (value == 15) {
state = 90;
response = 0;
} else {
state = 0;
response = 5;
}
break;
}
case 3: {
compression = value;
response = 0;
state = 4;
break;
}
case 4: {
dataLengthLSB = value;
response = 0;
state = 5;
break;
}
case 5: {
dataLengthMSB = value;
response = 0;
state = 6;
break;
}
case 6: {
response = 0;
state = 7;
break;
}
case 7: {
response = 129;
state = 8;
break;
}
case 8: {
response = statusCode;
state = 0;
break;
}
case 20: {
compression = value;
response = 0;
state = 21;
break;
}
case 21: {
dataLengthLSB = value;
response = 0;
state = 22;
break;
}
case 22: {
dataLengthMSB = value;
response = 0;
state = 23;
dataPosition = 256 * dataLengthMSB + dataLengthLSB;
break;
}
case 23: {
dataPosition--;
if (dataPosition == 0 || dataPosition == 65535) {
state = 24;
} else {
state = 23;
}
response = 0;
break;
}
case 24: {
response = 0;
state = 25;
break;
}
case 26: {
response = acknowledgeCode;
state = 27;
break;
}
case 27: {
response = statusCode;
state = 0;
break;
}
case 50: {
response = 0;
state = 51;
break;
}
case 51: {
response = 0;
state = 52;
break;
}
case 52: {
response = 0;
state = 53;
break;
}
case 53: {
response = 0;
state = 54;
break;
}
case 54: {
response = 0;
state = 55;
break;
}
case 55: {
response = 0;
state = 56;
break;
}
case 56: {
response = 0;
state = 57;
break;
}
case 57: {
response = 0;
state = 58;
break;
}
case 58: {
response = acknowledgeCode;
state = 59;
break;
}
case 59: {
response = statusCode;
state = 0;
break;
}
case 90: {
response = 0;
state = 91;
break;
}
case 91: {
response = 0;
state = 92;
break;
}
case 92: {
response = 0;
state = 93;
break;
}
case 93: {
response = 0;
state = 94;
break;
}
case 94: {
response = 129;
state = 95;
break;
}
case 95: {
response = statusCode;
state = 0;
break;
}
default: {
response = 0;
state = 0;
break;
}
}
fprintf(stderr, "send 0x%02x\n", response);
if (tabby_link_send(fd, &response, 1) < 0) {
fprintf(stderr, "%s: %s: %s: %s\n", argv[0], "tabby_link_send()",
argv[1], strerror(errno));
goto error_link_send;
}
fprintf(stderr, "Got a packet\n");
}
tabby_link_close(fd);

56
include/tabby/printer.h Normal file
View file

@ -0,0 +1,56 @@
#ifndef _TABBY_PRINTER_H
#define _TABBY_PRINTER_H
#define TABBY_PRINTER_MAX_PACKET_SIZE 640
typedef enum {
TABBY_PRINTER_LOWBAT = (1 << 7),
TABBY_PRINTER_ER2 = (1 << 6),
TABBY_PRINTER_ER1 = (1 << 5),
TABBY_PRINTER_ER0 = (1 << 4),
TABBY_PRINTER_UNTRAN = (1 << 3),
TABBY_PRINTER_FULL = (1 << 2),
TABBY_PRINTER_BUSY = (1 << 1),
TABBY_PRINTER_SUM = (1 << 0)
} tabby_printer_status;
/*
* Data definitions for packets sent from Game Boy to printer
*/
typedef struct _tabby_printer_packet_header {
union {
struct {
uint8_t preamble[2],
type,
compression;
uint16_t size;
};
uint8_t data[6];
};
} tabby_printer_packet_header;
typedef struct _tabby_printer_packet_footer {
union {
struct {
uint16_t checksum;
uint8_t peripheral,
status;
};
uint8_t data[4];
};
} tabby_printer_packet_footer;
/*
* Methods for communicating with Game Boy as a printer
*/
int tabby_printer_packet_recv(int fd, tabby_printer_packet_header *header,
void *body,
tabby_printer_packet_footer *footer);
int tabby_printer_response_send(int fd, uint8_t device, uint8_t status);
#endif /* _TABBY_PRINTER_H */

View file

@ -11,8 +11,8 @@ HEADERS_LOCAL =
HEADERS_BUILD = $(HEADERS_LOCAL) \
$(addprefix $(INCLUDE_PATH)/$(HEADER_SUBDIR)/,$(HEADERS))
HEADERS = link.h
OBJS = link.o
HEADERS = link.h printer.h
OBJS = link.o printer.o
VERSION_MAJOR = 0
VERSION_MINOR = 0.1

99
src/printer.c Normal file
View file

@ -0,0 +1,99 @@
#include <errno.h>
#include <tabby/link.h>
#include <tabby/printer.h>
#define PACKET_RECV_ERROR_THRESHOLD 30
static uint16_t checksum(tabby_printer_packet_header *header, void *body) {
uint16_t checksum = header->data[2]
+ header->data[3]
+ header->data[4]
+ header->data[5];
size_t i;
for (i=0; i<header->size; i++) {
checksum += ((uint8_t *)body)[i];
}
return checksum;
}
int tabby_printer_packet_recv(int fd, tabby_printer_packet_header *header,
void *body,
tabby_printer_packet_footer *footer) {
ssize_t len;
size_t i = 0,
b = 0,
f = 0;
uint8_t value,
last;
int started = 0;
memset(header, '\0', sizeof(*header));
memset(footer, '\0', sizeof(*footer));
while ((len = tabby_link_recv(fd, &value, 1)) >= 0) {
if (started) {
if (i == 2) {
header->type = value;
} else if (i == 3) {
header->compression = value;
} else if (i == 4 || i == 5) {
header->size <<= 8;
header->size |= value;
} else if (i > 5 && b < header->size) {
((uint8_t *)body)[b++] = value;
} else if (b >= header->size && f < 2) {
footer->checksum <<= 8;
footer->checksum |= value;
f++;
} else if (f >= 2) {
footer->data[f++] = value;
if (f == sizeof(*footer)) {
if (checksum(header, body) != footer->checksum) {
errno = EIO;
goto error_io;
}
return 0;
}
}
} else {
if (last == 0x88 && value == 0x33) {
started = 1;
i = 2;
b = 0;
f = 0;
} else if (i == PACKET_RECV_ERROR_THRESHOLD) {
errno = EIO;
goto error_io;
}
}
last = value;
i++;
}
return errno = 0;
error_io:
return -errno;
}
int tabby_printer_response_send(int fd, uint8_t device, uint8_t status) {
uint8_t response[2] = {
device, status
};
return tabby_link_send(fd, &response, sizeof(response));
}