123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116 |
- // Copyright 2015 by Thorsten von Eicken, see LICENSE.txt
- #include "esp8266.h"
- #include "uart.h"
- #include "crc16.h"
- #include "serbridge.h"
- #include "console.h"
- #include "cmd.h"
- #ifdef SLIP_DBG
- #define DBG(format, ...) do { os_printf(format, ## __VA_ARGS__); } while(0)
- #else
- #define DBG(format, ...) do { } while(0)
- #endif
- extern void ICACHE_FLASH_ATTR console_process(char *buf, short len);
- // This SLIP parser tries to conform to RFC 1055 https://tools.ietf.org/html/rfc1055.
- // It accumulates each packet into a static buffer and calls cmd_parse() when the end
- // of a packet is reached. It expects cmd_parse() to copy anything it needs from the
- // buffer elsewhere as the buffer is immediately reused.
- // One special feature is that if the first two characters of a packet are both printable or
- // \n or \r then the parser assumes it's dealing with console debug output and calls
- // slip_console(c) for each character and does not accumulate chars in the buffer until the
- // next SLIP_END marker is seen. This allows random console debug output to come in between
- // packets as long as each packet starts *and* ends with SLIP_END (which is an official
- // variation on the SLIP protocol).
- static bool slip_escaped; // true when prev char received is escape
- static bool slip_inpkt; // true when we're after SLIP_START and before SLIP_END
- #define SLIP_MAX 1024 // max length of SLIP packet
- static char slip_buf[SLIP_MAX]; // buffer for current SLIP packet
- static short slip_len; // accumulated length in slip_buf
- // SLIP process a packet or a bunch of debug console chars
- static void ICACHE_FLASH_ATTR
- slip_process() {
- if (slip_len > 2) {
- // proper SLIP packet, invoke command processor after checking CRC
- //os_printf("SLIP: rcv %d\n", slip_len);
- uint16_t crc = crc16_data((uint8_t*)slip_buf, slip_len-2, 0);
- uint16_t rcv = ((uint16_t)slip_buf[slip_len-2]) | ((uint16_t)slip_buf[slip_len-1] << 8);
- if (crc == rcv) {
- cmdParsePacket((uint8_t*)slip_buf, slip_len-2);
- } else {
- os_printf("SLIP: bad CRC, crc=%04x rcv=%04x len=%d\n", crc, rcv, slip_len);
- for (short i=0; i<slip_len; i++) {
- if (slip_buf[i] >= ' ' && slip_buf[i] <= '~') {
- DBG("%c", slip_buf[i]);
- } else {
- DBG("\\%02X", slip_buf[i]);
- }
- }
- DBG("\n");
- }
- }
- }
- // determine whether a character is printable or not (or \r \n)
- static bool ICACHE_FLASH_ATTR
- slip_printable(char c) {
- return (c >= ' ' && c <= '~') || c == '\n' || c == '\r';
- }
- static void ICACHE_FLASH_ATTR
- slip_reset() {
- //os_printf("SLIP: reset\n");
- slip_inpkt = true;
- slip_escaped = false;
- slip_len = 0;
- }
- // SLIP parse a single character
- static void ICACHE_FLASH_ATTR
- slip_parse_char(char c) {
- if (c == SLIP_END) {
- // either start or end of packet, process whatever we may have accumulated
- DBG("SLIP: start or end len=%d inpkt=%d\n", slip_len, slip_inpkt);
- if (slip_len > 0) {
- if (slip_len > 2 && slip_inpkt) slip_process();
- else console_process(slip_buf, slip_len);
- }
- slip_reset();
- } else if (slip_escaped) {
- // prev char was SLIP_ESC
- if (c == SLIP_ESC_END) c = SLIP_END;
- if (c == SLIP_ESC_ESC) c = SLIP_ESC;
- if (slip_len < SLIP_MAX) slip_buf[slip_len++] = c;
- slip_escaped = false;
- } else if (slip_inpkt && c == SLIP_ESC) {
- slip_escaped = true;
- } else {
- if (slip_len == 1 && slip_printable(slip_buf[0]) && slip_printable(c)) {
- // start of packet and it's a printable character, we're gonna assume that this is console text
- slip_inpkt = false;
- }
- if (slip_len < SLIP_MAX) slip_buf[slip_len++] = c;
- }
- }
- // callback with a buffer of characters that have arrived on the uart
- void ICACHE_FLASH_ATTR
- slip_parse_buf(char *buf, short length) {
- // do SLIP parsing
- for (short i=0; i<length; i++)
- slip_parse_char(buf[i]);
- // if we're in-between packets (debug console) then print it now
- if (!slip_inpkt && length > 0) {
- console_process(slip_buf, slip_len);
- slip_len = 0;
- }
- }
|