1 files changed, 64 insertions, 12 deletions

diff --git a/a8xd.c b/a8xd.c
index 52a8092..c322624 100644
--- a/a8xd.c
+++ b/a8xd.c
@@ -11,8 +11,11 @@
 const char **table = ata2utf;
 const char *inverse_on  = "\x1b[7m";
 const char *inverse_off = "\x1b[0m";
+const char *word_format = "%04x";
+const char *byte_format = "%02x";
 
-int verbose = 0, color = 1;
+int verbose = 0, color = 1, disp_offset = 0, maxlen = 0;
+int seek_whence = 0, seekpos = 0, filepos = 0, limit = 0;
 
 const char *self;
 
@@ -33,6 +36,50 @@ void print_help(void) {
 	printf("Usage: %s [-v] [file ...]\n", self);
 }
 
+int parse_num_arg(const char *arg) {
+	int got;
+
+	if(sscanf(arg, "0x%x", &got) != 1)
+		if(sscanf(arg, "$%x", &got) != 1)
+			if(sscanf(arg, "%d", &got) != 1) {
+				fprintf(stderr, "%s: invalid numeric argument '%s'.", self, arg);
+				exit(1);
+			}
+
+	return got;
+}
+
+void parse_seek_arg(const char *arg) {
+	seek_whence = SEEK_SET;
+
+	if(*arg == '-') {
+		seek_whence = SEEK_END;
+		arg++;
+	}
+
+	seekpos = parse_num_arg(arg);
+}
+
+int parse_offset_arg(const char *arg) {
+	int got;
+
+	got = parse_num_arg(arg);
+	if(got < 0)
+		die("negative arguments to -o (offset) are not supported.");
+
+	return got;
+}
+
+int parse_limit_arg(const char *arg) {
+	int got;
+
+	got = parse_num_arg(arg);
+	if(got < 0)
+		die("negative arguments to -l (limit) are not supported.");
+
+	return got;
+}
+
 FILE *open_input(const char *file) {
 	FILE *input;
 
@@ -83,16 +130,17 @@ char *get_color(unsigned char c) {
 
 void dump_line(const unsigned char *buf, int len) {
 	char hex[1024], asc[1024];
-	static int filepos = 0;
 	int hpos = 0, apos = 0, count = len;
 
 	memset(hex, 0, sizeof(hex));
 	memset(asc, 0, sizeof(asc));
 
-	printf("%04x:  ", filepos);
+	printf(word_format, filepos + disp_offset);
+	fputs(":  ", stdout);
+
 	while(len) {
 		if(color) hpos += sprintf(hex + hpos, "%s", get_color(*buf));
-		hpos += sprintf(hex + hpos, "%02x", *buf);
+		hpos += sprintf(hex + hpos, byte_format, *buf);
 		if(color) hpos += sprintf(hex + hpos, "%s", color_off);
 		hex[hpos++] = ' ';
 		if(count - len == 7) hex[hpos++] = ' ';
@@ -151,22 +199,26 @@ int main(int argc, char **argv) {
 		exit(0);
 	}
 
-	while( (opt = getopt(argc, argv, "vim")) != -1) {
+	while( (opt = getopt(argc, argv, "vimus:o:l")) != -1) {
 		switch(opt) {
 			case 'v': verbose = 1; break;
 			case 'i': table = ics2utf; break;
 			case 'm': color = 0; break;
+			case 'u': word_format = "%04X"; byte_format = "%02X"; break;
+			case 's': parse_seek_arg(optarg); break;
+			case 'o': disp_offset = parse_offset_arg(optarg); break;
+			case 'l': disp_offset = parse_limit_arg(optarg); break;
 			default: print_help(); exit(1); break;
 		}
 	}
 
-	if(optind >= argc) {
+	if(optind < argc - 1)
+		die("Only one filename is supported.");
+
+	if(optind >= argc)
 		result = a8xd("-");
-	} else {
-		while(optind < argc) {
-			result += a8xd(argv[optind]);
-			optind++;
-		}
-	}
+	else
+		result = a8xd(argv[optind]);
+
 	exit(result);
 }