listbas: add -r option, tweak doc.

1 files changed, 37 insertions, 3 deletions

diff --git a/listbas.c b/listbas.c
index 338e8d0..3226340 100644
--- a/listbas.c
+++ b/listbas.c
@@ -79,6 +79,8 @@ int dump_tables = 0;  /* 1 with -D */
 int autodetect  = 1;  /* 0 with -b */
 int mixed_case  = 1;  /* 0 with -k, or if input is B_ATARI or B_APLUS */
 int indent =      1;  /* 0 with -t, or if input is B_ATARI */
+int startline =   0;  /* -r */
+int endline   =   32767;  /* -r */
 
 /* change these with -c */
 int color_cmd =       C_YELLOW;
@@ -151,8 +153,37 @@ int get_bas_type(char *arg) {
 	exit(1);
 }
 
+void get_line_range(const char *arg) {
+	int val = 0, comma = 0;
+	const char *p = arg;
+
+	while(*p) {
+		if(*p >= '0' && *p <= '9') {
+			val *= 10;
+			val += *p - '0';
+			if(val > 32768) die("Invalid line number for -r (range is 0-32768).");
+		} else if(*p == ',' || *p == '-') {
+			if(comma) die("Invalid argument for -r (too many commas).");
+			comma++;
+			startline = val;
+			val = 0;
+		} else {
+			if(comma) die("Invalid argument for -r (only digits and comma allowed).");
+		}
+		p++;
+	}
+
+	if(comma)
+		endline = val ? val : 32767;
+	else
+		startline = endline = val;
+
+	if(endline < startline)
+		die("Invalid argument for -r (end > start).");
+}
+
 void print_help(void) {
-	printf("Usage: %s [-a|-d|-m|-x|-U] [-B] [-i] [-l] [-u] [-n|-C] [-v] [-c *colors*] [-k] [-t] <inputfile>\n", self);
+	printf("Usage: %s [-a|-d|-m|-x|-U] [-B] [-i] [-l] [-u] [-n|-C] [-v] [-c *colors*] [-r *start,end* ] [-k] [-t] <inputfile>\n", self);
 	printf("  -b <XX>: set BASIC type. XX is: a = atari, t = turbo, xl, xe, a+.\n");
 	printf("  -U: output ATASCII as Unicode/UTF-8 (this is the default).\n");
 	printf("  -a: output raw ATASCII.\n");
@@ -168,6 +199,7 @@ void print_help(void) {
 	printf("  -c: use custom colors (see man page).\n");
 	printf("  -k: disable mixed case keywords for BXL/BXE (e.g. Print).\n");
 	printf("  -t: disable Turbo/BXL/BXE indentation.\n");
+	printf("  -r: only list lines numbered from *start* to *end*.\n");
 	printf("  -v: verbose.\n");
 }
 
@@ -176,7 +208,7 @@ void parse_args(int argc, char **argv, int from_env) {
 
 	optind = 1;
 
-	while( (opt = getopt(argc, argv, "Db:UCviamnBdhxulc:kt")) != -1) {
+	while( (opt = getopt(argc, argv, "r:Db:UCviamnBdhxulc:kt")) != -1) {
 		switch(opt) {
 			case 'U': output_mode = M_UTF8;    break;
 			case 'a': output_mode = M_ATASCII; color = 0; break;
@@ -194,6 +226,7 @@ void parse_args(int argc, char **argv, int from_env) {
 			case 'k': mixed_case =  0; break;
 			case 't': indent =      0; break;
 			case 'b': autodetect = 0; bas_type = get_bas_type(optarg); break;
+			case 'r': get_line_range(optarg); break;
 			case 'c': parse_color_scheme(optarg); break;
 			case 'h': print_help(); exit(0);
 			default:
@@ -960,7 +993,8 @@ void init_callbacks(void) {
 
 void list(void) {
 	init_callbacks();
-	walk_code(0, 32767 + immediate);
+	if(endline == 32767 && immediate) endline++;
+	walk_code(startline, endline);
 }
 
 void init_bas_tables() {