dla2csv.xex: exit instead of crashing if user presses Ctrl-3.

2 files changed, 18 insertions, 11 deletions

diff --git a/dla2csv.c b/dla2csv.c
index 5d9c083..1cc6769 100644
--- a/dla2csv.c
+++ b/dla2csv.c
@@ -156,6 +156,19 @@ void show_dir(char drive) {
 	closedir(dir);
 	if(column) putchar('\n');
 }
+
+/* On the Atari, EOF is Ctrl-3. *Terrible* things happen if we
+	ever get EOF on stdin on the Atari! The screen shows gibberish
+	(display list gets mangled). Even calling exit() doesn't help.
+
+	There's not really a way to avoid this (other than not using stdin,
+	or hoping your users never press Ctrl-3), but we can avoid crashing
+	the Atari by jumping directly to DOS (do not call the exit stuff from
+	cc65's runtime, do not pass Go, do not collect $200). This seems to
+	work reliably, but I hesistate to document "Press Ctrl-3 to exit"...
+*/
+	#define exit_eof_stdin() (*(OS.dosvec))()
+
 #else
 	/* non-Atari is assumed to be POSIX (and not something like
 		Commodore or Apple II). */
@@ -166,6 +179,7 @@ void show_dir(char drive) {
 	#define enable_break() noop()
 	#define disable_break() noop()
 	#define init_console() noop()
+	#define exit_eof_stdin() exit(1)
 #endif
 
 char inbuf[INBUF_SIZE];
@@ -185,20 +199,13 @@ char *eoltypes[][2] = {
 };
 
 /* Read a string from stdin (E: on the Atari).
-	Exit on EOF (or Break key on the Atari, except we disable it).
-	On Linux, EOF is the ^D character, and this works.
-	On the Atari, EOF is ^3... On DOS 2.0S, we end up back at the DUP
-	menu... but SpartaDOS 3.2d locks up with a black screen. So don't
-	document ctrl-3 as a way to exit the program (too bad), and just
-	hope the user never presses it.
+	Exit if we get EOF on stdin (e.g. ^D on Linux, ^3 on Atari).
+	See exit_eof_stdin() comments above.
  */
 void readstring(void) {
-	char *result;
 	memset(stringbuf, 0, STRINGBUF_SIZE);
-	result = fgets(stringbuf, STRINGBUF_SIZE - 1, stdin);
-	if(result == NULL) {
-		exit(1);
-	}
+	if(fgets(stringbuf, STRINGBUF_SIZE - 1, stdin) == NULL)
+		exit_eof_stdin();
 }
 
 int prompt_yn(char *prompt, int default_y) {
diff --git a/dla2csv.xex b/dla2csv.xex
index ece05b8..eaaec27 100644
--- a/dla2csv.xex
+++ b/dla2csv.xex