From 49345782f6f0fc58a327b4b5cd279d5dc7ac8181 Mon Sep 17 00:00:00 2001
From: Markus Hitter <mah@jump-ing.de>
Date: Fri, 3 Jul 2015 00:45:25 +0200
Subject: [PATCH] G-code parser: make space a field delimiter.

This is neccessary to allow file names with leading digits. It's
still possible to send commands like M105 with spaces in between
("M1 05") and also to put space between character and number, like
"X 15.0".
---
 gcode_parse.c | 35 ++++++++++++++++-------------------
 1 file changed, 16 insertions(+), 19 deletions(-)

diff --git a/gcode_parse.c b/gcode_parse.c
index bb5ca6e..f31010c 100644
--- a/gcode_parse.c
+++ b/gcode_parse.c
@@ -111,11 +111,15 @@ void gcode_parse_char(uint8_t c) {
 #ifdef SIMULATOR
   sim_gcode_ch(c);
 #endif
-	// process previous field
-	if (last_field) {
-		// check if we're seeing a new field or end of line
-		// any character will start a new field, even invalid/unknown ones
-		if ((c >= 'A' && c <= 'Z') || c == '*' || (c == 10) || (c == 13)) {
+
+  // Skip comments and strings.
+  if (next_target.seen_semi_comment == 0 &&
+      next_target.seen_parens_comment == 0 &&
+      next_target.read_string == 0
+     ) {
+    // Check if the field has ended. Either by a new field, space or EOL.
+    if (last_field && ((c >= 'A' && c <= 'Z') || c == '*' || c == ' ' ||
+                       c == '\r' || c == '\n')) {
 			switch (last_field) {
 				case 'G':
 					next_target.G = read_digit.mantissa;
@@ -210,20 +214,12 @@ void gcode_parse_char(uint8_t c) {
 						serwrite_uint8(next_target.checksum_read);
 					break;
 			}
-			// reset for next field
-			last_field = 0;
-			read_digit.sign = read_digit.mantissa = read_digit.exponent = 0;
 		}
-	}
 
-  // Skip comments and strings.
-  if (next_target.seen_semi_comment == 0 &&
-      next_target.seen_parens_comment == 0 &&
-      next_target.read_string == 0
-     ) {
 		// new field?
 		if ((c >= 'A' && c <= 'Z') || c == '*') {
 			last_field = c;
+      read_digit.sign = read_digit.mantissa = read_digit.exponent = 0;
 			if (DEBUG_ECHO && (debug_flags & DEBUG_ECHO))
 				serial_writechar(c);
 		}
@@ -292,10 +288,10 @@ void gcode_parse_char(uint8_t c) {
 
         // comments
         case ';':
-          next_target.seen_semi_comment = 1;
+          next_target.seen_semi_comment = 1;    // Reset by EOL.
           break;
         case '(':
-          next_target.seen_parens_comment = 1;
+          next_target.seen_parens_comment = 1;  // Reset by ')' or EOL.
           break;
 
         // now for some numeracy
@@ -390,7 +386,8 @@ void gcode_parse_char(uint8_t c) {
       next_target.seen_semi_comment = next_target.seen_parens_comment = \
       next_target.read_string = next_target.checksum_read = \
       next_target.checksum_calculated = 0;
-		// last_field and read_digit are reset above already
+      last_field = 0;
+      read_digit.sign = read_digit.mantissa = read_digit.exponent = 0;
 
 		if (next_target.option_all_relative) {
       next_target.target.axis[X] = next_target.target.axis[Y] = next_target.target.axis[Z] = 0;
@@ -403,10 +400,10 @@ void gcode_parse_char(uint8_t c) {
   #ifdef SD
   // Handle string reading. After checking for EOL.
   if (next_target.read_string) {
-    if (c == ' ' || c == '*') {
+    if ((str_buf_ptr && c == ' ') || c == '*') {
       next_target.read_string = 0;
     }
-    else if (str_buf_ptr < STR_BUF_LEN) {
+    else if (c != ' ' && str_buf_ptr < STR_BUF_LEN) {
       gcode_str_buf[str_buf_ptr] = c;
       str_buf_ptr++;
       gcode_str_buf[str_buf_ptr] = '\0';