Leading whitespace is now ignored and blank lines will not throw off where the error mark is displayed. Start of labels.

src/vecparse.c

@@ -21,6 +21,7 @@
 
 
 #include <errno.h>
+#include <ctype.h>
 #include "common.h"
 #include "vecparse.h"
 
@@ -38,6 +39,11 @@ typedef struct OperatorsS {
 	ParserMathT     id;
 } OperatorsT;
 
+typedef struct LabelS {
+	char *key;
+	int   value;
+} LabelT;
+
 
 static void      ensureBufferSize(VecByteCodeT *bytecode, int needed);
 static void      outputByte(VecByteCodeT *bytecode, unsigned short word);
@@ -47,6 +53,7 @@ static gboolean parserGetWord(char *word, char **tokenEnd);
 static gboolean  parserGetX(char **tokenEnd, char **variables, int *x);
 static gboolean  parserGetXY(char **tokenEnd, char **variables, int *x, int *y);
 static gboolean  parserGetXYZ(char **tokenEnd, char **variables, int *x, int *y, int *z);
+static char     *strtoke(char *str, const char *delim, char **savePtr);
 
 
 static void ensureBufferSize(VecByteCodeT *bytecode, int needed) {
@@ -101,7 +108,6 @@ static gboolean parserGetNextValue(char *token, char **valueEnd, char **variable
 		// It's a variable.  Do we know it?
 		*x = -1;
 		for (index=0; index<arrlen(variables); index++) {
-			printf("Checking GN %d of %ld, %s = %s\n", index, arrlen(variables),  variables[index], value);
 			if (strcasecmp(variables[index], value) == 0) {
 				// Set MSb to indicate it's a variable.
 				index |= 0x8000;
@@ -159,7 +165,6 @@ static gboolean parserGetX(char **tokenEnd, char **variables, int *x) {
 		// It's a variable.  Do we know it?
 		*x = -1;
 		for (index=0; index<arrlen(variables); index++) {
-			printf("Checking GX %d of %ld, %s = %s\n", index, arrlen(variables),  variables[index], value);
 			if (strcasecmp(variables[index], value) == 0) {
 				// Set MSb to indicate it's a variable.
 				index |= 0x8000;
@@ -222,6 +227,59 @@ static gboolean parserGetXYZ(char **tokenEnd, char **variables, int *x, int *y,
 }
 
 
+// Custom strtok_r because:
+//   A sequence of two or more contiguous delimiter bytes in the
+//   parsed string is considered to be a single delimiter.
+// Which is exactly what we don't want for the line parser.
+static char *strtoke(char *str, const char *delim, char **savePtr) {
+	/*
+	char *end = NULL;
+
+	if (str == NULL) {
+		str = *savePtr;
+	}
+
+	if (*str == 0) {
+		*savePtr = str;
+		return NULL;
+	}
+
+	str = strpbrk(str, delim);
+	end = str + 1;
+
+	if (*end == 0) {
+		*savePtr++ = end;
+		return str;
+	}
+
+	*end = 0;
+	*savePtr = end + 1;
+
+	return str;
+	 */
+	char *token = NULL; // found token
+	// assign new start in case
+	if (str) {
+		*savePtr = str;
+	}
+	// check whether text to parse left
+	if (!*savePtr) {
+		return NULL;
+	}
+	// remember current start as found token
+	token = *savePtr;
+	// find next occurrence of delim
+	*savePtr = strpbrk(*savePtr, delim);
+	// replace delim with terminator and move start to follower
+	if (*savePtr) {
+		**savePtr = 0;
+		*savePtr = *savePtr + 1;
+	}
+	// done
+	return token;
+}
+
+
 int vecparser(char *programIn, VecByteCodeT *bytecode) {
 	int          keyword;
 	char        *line;
@@ -239,6 +297,7 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 	PointT       p2;
 	PointT      *points     = NULL;
 	char       **variables  = NULL;
+	LabelT      *labels     = NULL;
 	int          result     = -1;  // Returns -1 on success or line number of first error.
 	KeywordsT    commands[] = {
 			{ "BOX",       PARSE_BOX        },
@@ -273,15 +332,26 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 
 	// Parse code.
 	lineNumber = 0;
-	line = strtok_r(programIn, "\n", &lineEnd);
+	line = strtoke(programIn, "\n", &lineEnd);
+	while (line != NULL && (line[0] == ' ' || line[0] == '\t')) line++;
 	while (line != NULL) {
 
+		printf("%d [%s]\n", lineNumber, line);
+
 		// Get the first token on the line.
 		token = strtok_r(line, " ", &tokenEnd);
 
 		// Is this something we care about?  It'll be math, a label, or a keyword.
 		lineOkay = FALSE;
 
+		// Is this a blank line?
+		if (token == NULL) {
+
+			// Yep - just move on.
+			lineOkay = TRUE;
+
+		} else {  // blank line
+
 			// Is it math?
 			if (strlen(token) > 1 && token[0] == '%') {
 
@@ -290,7 +360,7 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 				// Look up variable index in table, or add it if needed.
 				// Variable index is stored in y1 for later.
 				y1 = -1;
-			for (y2=0; y2<arrlen(variables); y2++) {
+				for (y2 = 0; y2 < arrlen(variables); y2++) {
 					if (strcasecmp(variables[y2], token) == 0) {
 						y1 = y2;  // Found.
 						break;
@@ -317,12 +387,6 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 							outputByte(bytecode, math[keyword].id);
 							outputWord(bytecode, x1);
 							lineOkay = TRUE;
-						//***DEBUG***
-						if (math[keyword].id == MATH_ASSIGN) {
-							for (y1=0; y1<arrlen(variables); y1++) {
-								printf("Variable %d = %s\n", y1, variables[y1]);
-							}
-						}
 							break;
 						}
 						keyword++;
@@ -336,6 +400,20 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 
 					// It's a label.
 
+					// Have we already used this label?
+					x2 = -1;
+					for (x1 = 0; x1 < hmlen(labels); x1++) {
+						if (strcasecmp(token, labels[x1].key) == 0) {
+							x2 = x1;
+							break;
+						}
+					}
+					if (x2 < 0) {
+						// New label.  Add to hashmap.
+						hmput(labels, token, bytecode->length);
+						lineOkay = TRUE;
+					}
+
 				} else {  // doing a label
 
 					// It's a keyword.
@@ -559,6 +637,8 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 
 			} // math
 
+		} // blank line
+
 		// Is everything still okay?
 		if (!lineOkay) {
 			// Nope - error.
@@ -567,7 +647,8 @@ int vecparser(char *programIn, VecByteCodeT *bytecode) {
 		}
 
 		// Move to next line.
-		line = strtok_r(NULL, "\n", &lineEnd);
+		line = strtoke(NULL, "\n", &lineEnd);
+		while (line != NULL && (line[0] == ' ' || line[0] == '\t')) line++;
 		lineNumber++;
 	}  // read program line