- When mbrtowc() returns -2 when given all the remaining chars in a

string, set an end-of-line flag and avoid calling mbrtowc() again
  for any of the incomplete characters that remain in the string.
- Use "mbs" for the multi-byte state variable name (for consistency).
- Use the new MB_INVALID and MB_INCOMPLETE defines for the size_t
  -1 and -2 values (respectively).

Src/Zle/complist.c

@@ -572,14 +572,14 @@ clnicezputs(Listcols colors, char *s, int ml)
      * umlen is the full length of the unmetafied string
      * width is the full printing width of a prettified character,
      *  including both ASCII prettification and the wide character itself.
-     * ps is the shift state of the conversion to wide characters.
+     * mbs is the shift state of the conversion to wide characters.
      */
     char *ums, *uptr, *sptr, *wptr;
-    int umleft, umlen;
+    int umleft, umlen, eol = 0;
     size_t width;
-    mbstate_t ps;
+    mbstate_t mbs;
 
-    memset(&ps, 0, sizeof(ps));
+    memset(&mbs, 0, sizeof mbs);
     ums = ztrdup(s);
     untokenize(ums);
     uptr = unmetafy(ums, &umlen);
@@ -589,11 +589,13 @@ clnicezputs(Listcols colors, char *s, int ml)
 	initiscol(colors);
 
     while (umleft > 0) {
-	size_t cnt = mbrtowc(&cc, uptr, umleft, &ps);
+	size_t cnt = eol ? MB_INVALID : mbrtowc(&cc, uptr, umleft, &mbs);
 
 	switch (cnt) {
-	case (size_t)-2:
-	case (size_t)-1:
+	case MB_INCOMPLETE:
+	    eol = 1;
+	    /* FALL THROUGH */
+	case MB_INVALID:
 	    /* This handles byte values that aren't valid wide-character
 	     * sequences. */
 	    sptr = nicechar(STOUC(*uptr));
@@ -601,8 +603,8 @@ clnicezputs(Listcols colors, char *s, int ml)
 	    width = strlen(sptr);
 	    wptr = sptr + width;
 	    cnt = 1;
-	    /* Get ps out of its undefined state. */
-	    memset(&ps, 0, sizeof ps);
+	    /* Get mbs out of its undefined state. */
+	    memset(&mbs, 0, sizeof mbs);
 	    break;
 	case 0:
 	    /* This handles a '\0' in the input (which is a real char

Src/Zle/compmatch.c

@@ -1587,7 +1587,7 @@ sub_match(Cmdata md, char *str, int len, int sfx)
 #ifdef MULTIBYTE_SUPPORT
     int fulllen = len;
     char *fullstr = str;
-    mbstate_t ps;
+    mbstate_t mbs;
 #endif
 
     if (sfx) {
@@ -1629,7 +1629,7 @@ sub_match(Cmdata md, char *str, int len, int sfx)
 	 */
 	q = sfx ? str - l : str + l;
 	if (q != fullstr) {
-	    memset(&ps, 0, sizeof(ps));
+	    memset(&mbs, 0, sizeof mbs);
 	    /*
 	     * Otherwise read characters from the start of the original
 	     * string until we reach or pass the match point.  This
@@ -1645,7 +1645,7 @@ sub_match(Cmdata md, char *str, int len, int sfx)
 		 * ret must, in fact, be set by the current logic,
 		 * but gcc doesn't realise (at least some versions don't).
 		 */
-		size_t cnt = (size_t)-1;
+		size_t cnt = MB_INVALID;
 		int diff;
 		char *p2;
 
@@ -1655,12 +1655,12 @@ sub_match(Cmdata md, char *str, int len, int sfx)
 		 */
 		for (p2 = p; p2 < fullstr + fulllen; p2++) {
 		    char curchar = (*p2 == Meta) ? (*++p2 ^ 32) : *p2;
-		    cnt = mbrtowc(&wc, &curchar, 1, &ps);
+		    cnt = mbrtowc(&wc, &curchar, 1, &mbs);
 		    /* Continue while character is incomplete. */
-		    if (cnt != (size_t)-2)
+		    if (cnt != MB_INCOMPLETE)
 			break;
 		}
-		if (cnt == (size_t)-1 || cnt == (size_t)-2) {
+		if (cnt == MB_INVALID || cnt == MB_INCOMPLETE) {
 		    /* not a valid character, give up test */
 		    break;
 		}

Src/Zle/zle_main.c

@@ -761,7 +761,7 @@ getrestchar(int inchar)
     char c = inchar;
     wchar_t outchar;
     int timeout;
-    static mbstate_t ps;
+    static mbstate_t mbs;
 
     /*
      * We are guaranteed to set a valid wide last character,
@@ -772,7 +772,7 @@ getrestchar(int inchar)
 
     if (inchar == EOF) {
 	/* End of input, so reset the shift state. */
-	memset(&ps, 0, sizeof(ps));
+	memset(&mbs, 0, sizeof mbs);
 	return lastchar_wide = WEOF;
     }
 
@@ -781,15 +781,15 @@ getrestchar(int inchar)
      * any other character.
      */
     while (1) {
-	size_t cnt = mbrtowc(&outchar, &c, 1, &ps);
-	if (cnt == (size_t)-1) {
+	size_t cnt = mbrtowc(&outchar, &c, 1, &mbs);
+	if (cnt == MB_INVALID) {
 	    /*
 	     * Invalid input.  Hmm, what's the right thing to do here?
 	     */
-	    memset(&ps, 0, sizeof(ps));
+	    memset(&mbs, 0, sizeof mbs);
 	    return lastchar_wide = WEOF;
 	}
-	if (cnt != (size_t)-2)
+	if (cnt != MB_INCOMPLETE)
 	    break;
 
 	/*
@@ -802,7 +802,7 @@ getrestchar(int inchar)
 	/* getbyte deliberately resets lastchar_wide_valid */
 	lastchar_wide_valid = 1;
 	if (inchar == EOF) {
-	    memset(&ps, 0, sizeof(ps));
+	    memset(&mbs, 0, sizeof mbs);
 	    if (timeout)
 	    {
 		/*

Src/Zle/zle_refresh.c

@@ -1446,6 +1446,7 @@ singlerefresh(ZLE_STRING_T tmpline, int tmpll, int tmpcs)
 	refreshop = *obuf;	/* pointer to old video buffer */
     int t0,			/* tmp			       */
 	vsiz,			/* size of new video buffer    */
+	eol = 0,		/* has mbrtowc() returned -2?  */
 	nvcs = 0;		/* new video cursor column     */
 #ifdef MULTIBYTE_SUPPORT
     /*
@@ -1455,7 +1456,7 @@ singlerefresh(ZLE_STRING_T tmpline, int tmpll, int tmpcs)
     ZLE_STRING_T lpwbuf, lpwp;
     char *lpptr,		/* pointer into multibyte lprompt */
 	*lpend;			/* end of multibyte lprompt */
-    mbstate_t ps;		/* shift state */
+    mbstate_t mbs;		/* shift state */
 #endif
 
     nlnct = 1;
@@ -1490,18 +1491,26 @@ singlerefresh(ZLE_STRING_T tmpline, int tmpll, int tmpcs)
     lpwp = lpwbuf = (ZLE_STRING_T)zalloc((lpend - lpromptbuf)
 					 * sizeof(*lpwbuf));
     /* Reset shift state, maybe. */
-    memset(&ps, '\0', sizeof(ps));
+    memset(&mbs, '\0', sizeof mbs);
     for (lpptr = lpromptbuf; lpptr < lpend; ) {
-	size_t cnt = mbrtowc(lpwp, lpptr, lpend - lpptr, &ps);
-	if (cnt != 0 && cnt != (size_t)-1 && cnt != (size_t)-2) {
-	    /* successfully converted */
-	    lpptr += cnt;
-	    lpwp++;
-	} else {
+	size_t cnt = mbrtowc(lpwp, lpptr, lpend - lpptr, &mbs);
+	switch (cnt) {
+	case MB_INCOMPLETE:
+	    eol = 1;
+	    /* FALL THROUGH */
+	case MB_INVALID:
+	    memset(&mbs, '\0', sizeof mbs);
+	    /* FALL THROUGH */
+	case 0:
 	    /* dunno, try to recover */
 	    lpptr++;
 	    *lpwp++ = ZWC('?');
-	    memset(&ps, '\0', sizeof(ps));
+	    break;
+	default:
+	    /* successfully converted */
+	    lpptr += cnt;
+	    lpwp++;
+	    break;
 	}
     }
     if (lpwp - lpwbuf < lpromptw) {