\x escape sequence support

This patch adds \x.. escape sequence in freeform strings and in trigger
filter.

common/common.c

@@ -558,3 +558,54 @@ uint64_t get_cyclecounter64I(void)
  return cyclecounter64;
 }
 
+static uint8_t hexchartonibble(char hex)
+{
+ if (hex >= '0' && hex <= '9') return hex - '0';
+ if (hex >= 'a' && hex <='f') return hex - 'a' + 10;
+ if (hex >= 'A' && hex <='F') return hex - 'A' + 10;
+ return 0;
+}
+
+static uint8_t hex2byte(char * hex)
+{
+ uint8_t val = 0;
+ val = (hexchartonibble(hex[0]) << 4);
+ val += hexchartonibble(hex[1]);
+ return val;
+}
+
+uint8_t parse_escaped_string(char * input, uint8_t * output)
+{
+ uint8_t count=0;
+ uint8_t i=0;
+ uint8_t num_bytes=0;
+ unsigned char c;
+
+ /* Poor man's strlen() */
+ while (input[count] != '\0') {
+ count++;
+ }
+
+ while(i<count) {
+ if(input[i] == '\\'){
+ switch(input[i+1]) {
+ case '\\':
+ output[num_bytes++] = '\\';
+ i++;
+ break;
+ case 'x':
+ c = (char)hex2byte(&(input[i+2]));
+ output[num_bytes++] = c;
+ i+=3;
+ break;
+ default:
+ i++;
+ break;
+ }
+ } else {
+ output[num_bytes++] = input[i];
+ }
+ i++;
+ }
+ return num_bytes;
+}

common/common.h

@@ -172,5 +172,6 @@ void cprintf(t_hydra_console *con, const char *fmt, ...);
 void print_dbg(const char *data, const uint32_t size);
 void printf_dbg(const char *fmt, ...);
 void print_hex(t_hydra_console *con, uint8_t* data, uint8_t size);
+uint8_t parse_escaped_string(char * input, uint8_t * output);
 
 #endif /* _COMMON_H_ */

hydrabus/hydrabus_mode.c

@@ -24,6 +24,7 @@
 
 #include "hydrabus.h"
 #include "hydrabus_mode.h"
+#include "hydrabus_trigger.h"
 #include "mode_config.h"
 
 #include "bsp_rng.h"
@@ -256,6 +257,9 @@ int cmd_mode_exec(t_hydra_console *con, t_tokenline_parsed *p)
  */
  t += tokens_used - 1;
  break;
+ case T_TRIGGER:
+ t += cmd_trigger(con, p, t + 1);
+ break;
  case T_EXIT:
  MAYBE_CALL(con->mode->exec->cleanup);
  mode_exit(con, p);
@@ -323,23 +327,15 @@ static int chomp_strings(t_hydra_console *con, t_tokenline_parsed *p,
  int token_pos, unsigned int *num_bytes)
 {
  mode_config_proto_t* p_proto = &con->mode->proto;
- int count, t, i;
+ int t;
  char * str;
 
  t = token_pos;
  t++;
  *num_bytes = 0;
  str = p->buf + p->tokens[t++];
- count=0;
- /* Poor man's strlen() */
- while (str[count] != '\0') {
- count++;
- }
- i=0;
- while(i<count) {
- p_proto->buffer_tx[(*num_bytes)++] = str[i];
- i++;
- }
+
+ *num_bytes = parse_escaped_string(str, p_proto->buffer_tx);
 
  return t - token_pos;
 }

hydrabus/hydrabus_mode_uart.c

@@ -19,7 +19,6 @@
 #include "common.h"
 #include "hydrabus_mode_uart.h"
 #include "bsp_uart.h"
-#include "hydrabus_trigger.h"
 #include <string.h>
 
 #define UART_DEFAULT_SPEED (9600)
@@ -229,10 +228,6 @@ static int exec(t_hydra_console *con, t_tokenline_parsed *p, int token_pos)
  case T_BRIDGE:
  bridge(con);
  break;
- case T_TRIGGER:
- t++;
- t += cmd_trigger(con, p, t);
- break;
  default:
  return t - token_pos;
  }

hydrabus/hydrabus_trigger.c

@@ -87,8 +87,7 @@ int cmd_trigger(t_hydra_console *con, t_tokenline_parsed *p, int token_pos)
  switch (p->tokens[t]) {
  case T_FILTER:
  t += 2;
- trigger_length = strlen(p->buf + p->tokens[t]);
- memcpy(trigger_data, p->buf + p->tokens[t], trigger_length);
+ trigger_length = parse_escaped_string(p->buf + p->tokens[t], trigger_data);
 
  show_params(con);
  break;
@@ -99,6 +98,7 @@ int cmd_trigger(t_hydra_console *con, t_tokenline_parsed *p, int token_pos)
  break;
  case T_SHOW:
  t += show(con, p, t);
+ break;
  default:
  return t - token_pos;
  }