At last! After much delay, much faffing back and forth, and much

enhancement and fiddling, I have now massaged Arabeyes' first patch
into a form I'm happy to check in. Phew.

[originally from svn r4236]

1 files changed, 25 insertions, 6 deletions

diff --git a/ldisc.c b/ldisc.c
index e5727186..d57e6d17 100644
--- a/ldisc.c
+++ b/ldisc.c
@@ -32,13 +32,20 @@ static int plen(Ldisc ldisc, unsigned char c)
 	return 1;
     else if (c < 128)
 	return 2;		       /* ^x for some x */
+    else if (in_utf(ldisc->term) && c >= 0xC0)
+	return 1;		       /* UTF-8 introducer character
+					* (FIXME: combining / wide chars) */
+    else if (in_utf(ldisc->term) && c >= 0x80 && c < 0xC0)
+	return 0;		       /* UTF-8 followup character */
     else
-	return 4;		       /* <XY> for hex XY */
+	return 4;		       /* <XY> hex representation */
 }
 
 static void pwrite(Ldisc ldisc, unsigned char c)
 {
-    if ((c >= 32 && c <= 126) || (c >= 160 && !in_utf(ldisc->term))) {
+    if ((c >= 32 && c <= 126) ||
+	(!in_utf(ldisc->term) && c >= 0xA0) ||
+	(in_utf(ldisc->term) && c >= 0x80)) {
 	c_write(ldisc, (char *)&c, 1);
     } else if (c < 128) {
 	char cc[2];
@@ -52,6 +59,14 @@ static void pwrite(Ldisc ldisc, unsigned char c)
     }
 }
 
+static int char_start(Ldisc ldisc, unsigned char c)
+{
+    if (in_utf(ldisc->term))
+	return (c < 0x80 || c >= 0xC0);
+    else
+	return 1;
+}
+
 static void bsb(Ldisc ldisc, int n)
 {
     while (n--)
@@ -137,7 +152,9 @@ void ldisc_send(void *handle, char *buf, int len, int interactive)
 		c += KCTRL('@');
 	    switch (ldisc->quotenext ? ' ' : c) {
 		/*
-		 * ^h/^?: delete one char and output one BSB
+		 * ^h/^?: delete, and output BSBs, to return to
+		 * last character boundary (in UTF-8 mode this may
+		 * be more than one byte)
 		 * ^w: delete, and output BSBs, to return to last
 		 * space/nonspace boundary
 		 * ^u: delete, and output BSBs, to return to BOL
@@ -153,9 +170,11 @@ void ldisc_send(void *handle, char *buf, int len, int interactive)
 	      case KCTRL('H'):
 	      case KCTRL('?'):	       /* backspace/delete */
 		if (ldisc->buflen > 0) {
-		    if (ECHOING)
-			bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
-		    ldisc->buflen--;
+		    do {
+			if (ECHOING)
+			    bsb(ldisc, plen(ldisc, ldisc->buf[ldisc->buflen - 1]));
+			ldisc->buflen--;
+		    } while (!char_start(ldisc, ldisc->buf[ldisc->buflen]));
 		}
 		break;
 	      case CTRL('W'):	       /* delete word */