listamsb: warn on non-sequential or out-of-range line numbers.

1 files changed, 31 insertions, 9 deletions

diff --git a/listamsb.c b/listamsb.c
index a8a3e86..ee0d9a1 100644
--- a/listamsb.c
+++ b/listamsb.c
@@ -15,6 +15,10 @@
 #define BUFSIZ 4096
 #endif
 
+#define EOL 0x9b
+
+#define MAX_LINENO 63999
+
 const char *self;
 
 char pipe_command[BUFSIZ + 1] = { "a8cat" };
@@ -84,7 +88,7 @@ void unknown_token(int lineno, unsigned char byte, int ext) {
 }
 
 int next_line(void) {
-	int ptr, lineno, was_ff, in_string;
+	int ptr, lineno, was_ff, in_string, last_lineno = -1;
 	unsigned char byte;
 
 	/* pointer to last token on the line, offset by whatever MEMLO
@@ -97,12 +101,23 @@ int next_line(void) {
 		return -1;
 	}
 
-	/* TODO: sanity check line number: it must be < 64000, and greater than
-		the line before it (if there was one). */
 	lineno = read_word();
 	if(verbose)
 		fprintf(stderr, "found line number %d\n", lineno);
 
+	if(lineno <= last_lineno) {
+		fprintf(stderr, "%s: line number out of order (%d <= %d)\n",
+				self, lineno, last_lineno);
+	}
+
+	if(lineno > MAX_LINENO) {
+		fprintf(stderr, "%s: line number out range (%d > %d)\n",
+				self, lineno, MAX_LINENO);
+	}
+
+	last_lineno = lineno;
+
+	/* note that AMSB always puts a space after the line number in LIST */
 	fprintf(outfile, "%d ", lineno);
 
 	was_ff = 0;
@@ -133,6 +148,7 @@ int next_line(void) {
 			if( !(next == 0x9a || next == 0x9b) )
 				putc(byte, outfile);
 			ungetc(next, infile);
+			bytes_read--;
 		} else if(byte == '"') {
 			/* strings start but *don't end* with a double-quote */
 			in_string = 1;
@@ -156,7 +172,7 @@ int next_line(void) {
 		}
 	}
 
-	putc(0x9b, outfile);
+	putc(EOL, outfile);
 
 	return lineno;
 }
@@ -224,7 +240,7 @@ void open_output() {
 }
 
 int main(int argc, char **argv) {
-	int proglen, lineno;
+	int proglen, lineno, rv = 0;
 
 	set_self(argv[0]);
 
@@ -240,16 +256,22 @@ int main(int argc, char **argv) {
 		if(verbose)
 			fprintf(stderr, "line %d read OK\n", lineno);
 
-	/* TODO: sanity check proglen vs. file position */
 	if(verbose)
 		fprintf(stderr, "read %d bytes\n", bytes_read);;
 
-	if(need_pclose) pclose(outfile);
+	if(proglen == (bytes_read - 3)) {
+		if(verbose)
+			fprintf(stderr, "file size matches proglen\n");
+	} else {
+		fprintf(stderr, "%s: trailing garbage at EOF\n", self);
+	}
 
 	if(unknowns) {
 		fprintf(stderr, "%s: input has %d unknown tokens\n", self, unknowns);;
-		exit(2);
+		rv = 2;
 	}
 
-	exit(0);
+	if(need_pclose) pclose(outfile);
+
+	exit(rv);
 }