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Implement retry mechanism

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XANTRONIX Development 2016-06-05 01:58:30 -05:00
parent d670c605a1
commit 70f1fc349e
2 changed files with 36 additions and 15 deletions
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3
include/tabby/printer.h
View file

@ -1,6 +1,9 @@
#ifndef _TABBY_PRINTER_H #ifndef _TABBY_PRINTER_H
#define _TABBY_PRINTER_H #define _TABBY_PRINTER_H
#define TABBY_PRINTER_DEVICE_ID 0x81
#define TABBY_PRINTER_RETRY_COUNT 5
#define TABBY_PRINTER_MAX_PACKET_SIZE 640 #define TABBY_PRINTER_MAX_PACKET_SIZE 640
#define TABBY_PRINTER_BAND_SIZE 640 #define TABBY_PRINTER_BAND_SIZE 640

24
src/printer.c
View file

@ -107,11 +107,31 @@ error_io:
return -errno; return -errno;
} }
static inline int resend(tabby_printer_response *response) {
if (response->device != TABBY_PRINTER_DEVICE_ID) {
return 1;
}
if (response->status & (TABBY_PRINTER_ER0 | TABBY_PRINTER_SUM)) {
return 1;
}
return 0;
}
int tabby_printer_packet_send(int fd, int tabby_printer_packet_send(int fd,
tabby_printer_packet *header, tabby_printer_packet *header,
void *body, void *body,
tabby_printer_response *response) { tabby_printer_response *response) {
uint16_t sum = checksum(header, body); uint16_t sum = checksum(header, body);
int tries = TABBY_PRINTER_RETRY_COUNT;
do {
if (tries-- == 0) {
errno = EIO;
goto error_io;
}
if (write(fd, header, sizeof(*header)) < 0) { if (write(fd, header, sizeof(*header)) < 0) {
goto error_io; goto error_io;
@ -130,6 +150,7 @@ int tabby_printer_packet_send(int fd,
if (read(fd, response, sizeof(*response)) < 0) { if (read(fd, response, sizeof(*response)) < 0) {
goto error_io; goto error_io;
} }
} while (resend(response));
return 0; return 0;
@ -210,9 +231,6 @@ int tabby_printer_send_sheet(int fd, void *data,
} }
offset += TABBY_PRINTER_BAND_SIZE; offset += TABBY_PRINTER_BAND_SIZE;
printf("Sent band, got status %02x%02x\n",
current.device, current.status);
} }
init_header(&header, TABBY_PRINTER_PACKET_DATA, 0); init_header(&header, TABBY_PRINTER_PACKET_DATA, 0);