From 739758781030f107f260f587a4f9c1e8bdf70f58 Mon Sep 17 00:00:00 2001
From: "B. Watson" <urchlay@slackware.uk>
Date: Sat, 8 Jun 2024 13:12:23 -0400
Subject: dumpbas: clean up code, work on doc.

---
 dumpbas.c | 160 ++++++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 99 insertions(+), 61 deletions(-)

(limited to 'dumpbas.c')

diff --git a/dumpbas.c b/dumpbas.c
index b7607ea..2888b52 100644
--- a/dumpbas.c
+++ b/dumpbas.c
@@ -77,10 +77,58 @@ void print_atascii(unsigned char c) {
 	putchar('/');
 }
 
+/* REM, DATA, ERROR lines are terminated by $9B, a real EOL, not
+   the BASIC token. Since they're strings, print them in ASCII too. */
+int handle_text_stmt(int pos) {
+	unsigned char c;
+
+	do {
+		c = program[pos];
+		print_atascii(c);
+		printf("%02x ", c);
+		pos++;
+	} while(c != 0x9b);
+
+	return pos;
+}
+
+int handle_cmd(int pos) {
+	unsigned char tok = program[pos];
+
+	printf("!%02x ", tok);
+	switch(tok) {
+		case CMD_REM:
+		case CMD_DATA:
+		case CMD_ERROR:
+			return handle_text_stmt(pos + 1);
+		default:
+			return pos + 1;
+	}
+}
+
+void handle_string(int pos) {
+	int i, len;
+	len = program[pos + 1];
+	printf("$%02x =%02x \"", program[pos], len);
+	for(i = pos; i < pos + len; i++) {
+		unsigned char c = program[i + 2];
+		print_atascii(c);
+		printf("%02x%c", c, (i == (pos + len - 1) ? '"' : ' '));
+	}
+	putchar(' ');
+}
+
+void handle_num(int pos) {
+	int i;
+	printf("#%02x [", program[pos]);
+	for(i = 0; i < 6; i++)
+		printf("%02x%c", program[pos + 1 + i], (i == 5 ? ']' : ' '));
+	putchar(' ');
+}
+
 /* sorry, this is horrid, more like assembly than C. */
 int main(int argc, char **argv) {
-	int pos, nextpos, offset, soffset, lineno, cmd, i, end;
-	int numcount = 0, start_string = 0, end_string = 0;
+	int linepos, nextpos, offset, soffset, lineno, pos, end, tok;
 
 	set_self(*argv);
 	parse_general_args(argc, argv, print_help);
@@ -89,71 +137,61 @@ int main(int argc, char **argv) {
 	readfile();
 	parse_header();
 
-	pos = codestart;
-	while(pos < filelen) {
-		lineno = getword(pos);
-		offset = program[pos + 2];
-		nextpos = pos + offset;
-
-		if(lineno >= startlineno) {
-			printf("%5d@%04x (%02x %02x): ^%02x ", lineno, pos, program[pos], program[pos + 1], offset);
-
-			i = pos + 3;
-			while(i < nextpos) {
-				soffset = program[i];
-				end = pos + soffset;
-				while(i < end) {
-					printf("\n    >%02x ", program[i]); /* offset */
-					i++;
-					cmd = 1;
-					while(i < end) {
-						if(cmd) {
-							putchar('!');
-						} else if(program[i] == 0x0e && program[i - 1] != 0x0f && (i < start_string || i > end_string)) {
-							putchar('#');
-							numcount = 7;
-						} else if(program[i] == 0x0f) {
-							putchar('$');
-							start_string = i + 2;
-							end_string = start_string + program[i + 1];
-						}
-
-						if(numcount == 6)
-							putchar('[');
-
-						if(i == start_string)
-							putchar('"');
-
-						if(i == (start_string - 1))
-							putchar('=');
-
-						if(i >= start_string && i < end_string)
-							print_atascii(program[i]);
-
-						printf("%02x", program[i]);
-						if(i == (end - 1) && program[i] == 0x14)
-							putchar(':');
-
-						if(numcount) {
-							if(--numcount == 0)
-								putchar(']');
-						}
-
-						i++;
-						if(i == end_string)
-							putchar('"');
-
-						putchar(' ');
-						cmd = 0;
+	linepos = codestart;
+	while(linepos < filelen) { /* loop over lines */
+		lineno = getword(linepos);
+		offset = program[linepos + 2];
+		nextpos = linepos + offset;
+
+		if(offset < 6)
+			die("Can't dump a protected program, unprotect it first.");
+
+		if(lineno < startlineno) {
+			linepos = nextpos;
+			continue;
+		}
+
+		/* line header */
+		printf("%5d@%04x (%02x %02x): ^%02x ",
+				lineno, linepos, program[linepos], program[linepos + 1], offset);
+
+		pos = linepos + 3;
+		while(pos < nextpos) { /* loop over statements within a line */
+			soffset = program[pos];
+			end = linepos + soffset;
+
+			while(pos < end) {  /* loop over tokens within a statement */
+				printf("\n    >%02x ", program[pos++]); /* offset */
+				pos = handle_cmd(pos++); /* 1st token is the command */
+
+				while(pos < end) {     /* loop over operators */
+					tok = program[pos];
+					switch(tok) {
+						case OP_NUMCONST:
+							handle_num(pos);
+							pos += 7;
+							break;
+						case OP_STRCONST:
+							handle_string(pos);
+							pos += program[pos + 1] + 2;
+							break;
+						default:
+							printf("%02x", program[pos]);
+							if(pos == (end - 1) && tok == OP_EOS)
+								putchar(':');
+							else
+								putchar(' ');
+							pos++;
+							break;
 					}
 				}
 			}
-
-			putchar('\n');
 		}
 
+		putchar('\n');
+
 		if(lineno == endlineno) break;
-		pos = nextpos;
+		linepos = nextpos;
 	}
 
 	return 0;
-- 
cgit v1.2.3