Bug 225096 - [libteken] [PATCH] Add reverse wrap around to libteken
Summary: [libteken] [PATCH] Add reverse wrap around to libteken
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Only Me
Assignee: freebsd-bugs mailing list
URL:
Keywords: patch
Depends on:
Blocks:
 
Reported: 2018-01-12 01:34 UTC by florian_kaiser
Modified: 2019-05-21 21:01 UTC (History)
2 users (show)

See Also:


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Description florian_kaiser 2018-01-12 01:34:40 UTC
We needed the reverse wrap around in the teken library and I thought you might like it as well.

Cheers!



diff -u -r -N teken/teken.c teken_/teken.c
--- teken/teken.c	2018-01-12 01:48:10.832926321 +0100
+++ teken_/teken.c	2018-01-12 01:50:08.108822290 +0100
@@ -58,6 +58,7 @@
 #define	TS_CONS25	0x0040	/* cons25 emulation. */
 #define	TS_INSTRING	0x0080	/* Inside string. */
 #define	TS_CURSORKEYS	0x0100	/* Cursor keys mode. */
+#define	TS_REVWRAP	0x0200  /* reverse Wraparound */
 
 /* Character that blanks a cell. */
 #define	BLANK	' '
diff -u -r -N teken/teken_subr.h teken_/teken_subr.h
--- teken/teken_subr.h	2018-01-12 01:48:10.833926389 +0100
+++ teken_/teken_subr.h	2018-01-12 01:50:08.108822290 +0100
@@ -213,6 +213,16 @@
 		} else {
 			t->t_cursor.tp_col--;
 		}
+	} else if (t->t_stateflags & TS_REVWRAP)  {
+		if (t->t_cursor.tp_col == 0) {
+			if (t->t_cursor.tp_row == t->t_originreg.ts_begin)
+				return;
+			t->t_cursor.tp_row--;
+			t->t_cursor.tp_col = t->t_winsize.tp_col - 2;
+		} else {
+			t->t_cursor.tp_col--;
+			t->t_stateflags &= ~TS_WRAPPED;
+		}
 	} else {
 		if (t->t_cursor.tp_col == 0)
 			return;
Comment 1 florian_kaiser 2018-01-12 11:36:08 UTC
unfortunately I lost some lines in the previous diff...
here is the updated patch:


diff -u -r -N teken/teken.c teken_/teken.c
--- teken/teken.c	2018-01-12 01:48:10.832926321 +0100
+++ teken_/teken.c	2018-01-12 01:50:08.108822290 +0100
@@ -58,6 +58,7 @@
 #define	TS_CONS25	0x0040	/* cons25 emulation. */
 #define	TS_INSTRING	0x0080	/* Inside string. */
 #define	TS_CURSORKEYS	0x0100	/* Cursor keys mode. */
+#define	TS_REVWRAP	0x0200  /* reverse Wraparound */
 
 /* Character that blanks a cell. */
 #define	BLANK	' '
diff -u -r -N teken/teken_subr.h teken_/teken_subr.h
--- teken/teken_subr.h	2018-01-12 01:48:10.833926389 +0100
+++ teken_/teken_subr.h	2018-01-12 12:33:37.831931927 +0100
@@ -213,6 +213,16 @@
 		} else {
 			t->t_cursor.tp_col--;
 		}
+	} else if (t->t_stateflags & TS_REVWRAP)  {
+		if (t->t_cursor.tp_col == 0) {
+			if (t->t_cursor.tp_row == t->t_originreg.ts_begin)
+				return;
+			t->t_cursor.tp_row--;
+			t->t_cursor.tp_col = t->t_winsize.tp_col - 2;
+		} else {
+			t->t_cursor.tp_col--;
+			t->t_stateflags &= ~TS_WRAPPED;
+		}
 	} else {
 		if (t->t_cursor.tp_col == 0)
 			return;
@@ -934,7 +944,8 @@
 		teken_printf("DECRST allow 132\n");
 		break;
 	case 45: /* Disable reverse wraparound. */
-		teken_printf("DECRST reverse wraparound\n");
+		t->t_stateflags &= ~TS_REVWRAP;
+		teken_printf("DECRST reverse wraparound disabled\n");
 		break;
 	case 47: /* Switch to alternate buffer. */
 		teken_printf("Switch to alternate buffer\n");
@@ -1092,7 +1103,8 @@
 		teken_printf("DECSET allow 132\n");
 		break;
 	case 45: /* Enable reverse wraparound. */
-		teken_printf("DECSET reverse wraparound\n");
+		t->t_stateflags |= TS_REVWRAP;
+		teken_printf("DECSET reverse wraparound enabled\n");
 		break;
 	case 47: /* Switch to alternate buffer. */
 		teken_printf("Switch away from alternate buffer\n");
Comment 2 Ed Maste freebsd_committer 2019-05-21 19:29:26 UTC
Ed does this look good to go in?
Comment 3 Ed Schouten freebsd_committer 2019-05-21 21:01:40 UTC
Hey! The patch looks decent, but I'm wondering whether it's possible to merge some of the now redundant logic in teken_subr_backspace(), e.g.:

...
} else {
    if (t->t_cursor.tp_col == 0) {
        if ((t->t_stateflags & TS_REVWRAP) == 0)
            return;
        t->t_cursor.tp_row--;
        t->t_cursor.tp_col = t->t_winsize.tp_col - 2;
    } else {
        t->t_cursor.tp_col--;
        t->t_stateflags &= ~TS_WRAPPED;

    }
}

Also, I think you might need to take TS_WRAPPED into account. Depending on the value of that flag, you may need to jump to 't->t_winsize.tp_col - 1' or 't->t_winsize.tp_col - 2'.

Also, feel free to remove the teken_printf() calls there. They were just a debugging aid to display unsupported escape sequences.