stat_t gc_gcode_parser(char_t *block)
{
char_t *str = block; // gcode command or NUL string
char_t none = NUL;
char_t *com = &none; // gcode comment or NUL string
char_t *msg = &none; // gcode message or NUL string
uint8_t block_delete_flag;
// don't process Gcode blocks if in alarmed state
if (cm.machine_state == MACHINE_ALARM) return (STAT_MACHINE_ALARMED);
_normalize_gcode_block(str, &com, &msg, &block_delete_flag);
// Block delete omits the line if a / char is present in the first space
// For now this is unconditional and will always delete
// if ((block_delete_flag == true) && (cm_get_block_delete_switch() == true)) {
if (block_delete_flag == true) {
return (STAT_NOOP);
}
// queue a "(MSG" response
if (*msg != NUL) {
(void)cm_message(msg); // queue the message
}
return(_parse_gcode_block(block));
}
static void _normalize_gcode_block(char *block)
{
char c;
char *comment=0; // comment pointer - first char past opening paren
uint8_t i=0; // index for incoming characters
uint8_t j=0; // index for normalized characters
if (block[0] == '/') { // discard deleted blocks
block[0] = NUL;
return;
}
if (block[0] == '?') { // trap and return ? command
return;
}
// normalize the command block & mark the comment(if any)
while ((c = toupper(block[i++])) != NUL) {
if ((isupper(c)) || (isdigit(c))) { // capture common chars
block[j++] = c;
continue;
}
if (c == '(') { // detect & handle comments
block[j] = NUL;
comment = &block[i];
break;
}
if (c <= ' ') continue; // toss controls & whitespace
if (c == DEL) continue; // toss DELETE (0x7F)
if (strchr("!$%,;:?@^_~`\'\"", c)) // toss invalid punctuation
continue;
block[j++] = c;
}
block[j] = NUL; // terminate the command
if (comment != 0) {
if ((toupper(comment[0]) == 'M') &&
(toupper(comment[1]) == 'S') &&
(toupper(comment[2]) == 'G')) {
i=0;
while ((c = comment[i++]) != NUL) {// remove trailing parenthesis
if (c == ')') {
comment[--i] = NUL;
break;
}
}
(void)cm_message(comment+3);
}
}
}