49653: fix array indexing issue introduced with 49518 due to using de…

…cimal rather than hex 20

Also avoid comparing the current word against all options when the word
doesn't start with - or +.

ChangeLog

@@ -1,5 +1,8 @@
 2021-12-16  Oliver Kiddle  <opk@zsh.org>
 
+	* 49653: Src/Zle/computil.c: fix array indexing issue introduced
+	with 49518 due to using decimal rather than hex 20
+
 	* 49648 based on github #80 (Vincent Bernat):
 	Completion/Unix/Command/_find, Completion/Zsh/Type/_globquals:
 	invert before/since for date glob qualifiers completion

Src/Zle/computil.c

@@ -1088,10 +1088,10 @@ bslashcolon(char *s)
 static int
 single_index(char pre, char opt)
 {
-    if (opt <= 20 || opt > 0x7e)
+    if (opt <= 0x20 || opt > 0x7e)
 	return -1;
 
-    return opt + (pre == '-' ? -21 : 94 - 21);
+    return opt + (pre == '-' ? -0x21 : 94 - 0x21);
 }
 
 /* Parse an argument definition. */
@@ -2158,7 +2158,8 @@ ca_parse_line(Cadef d, Cadef all, int multi, int first)
 
 	/* See if it's an option. */
 
-	if (state.opt == 2 && (state.curopt = ca_get_opt(d, line, 0, &pe)) &&
+	if (state.opt == 2 && (*line == '-' || *line == '+') &&
+	    (state.curopt = ca_get_opt(d, line, 0, &pe)) &&
 	    (state.curopt->type == CAO_OEQUAL ?
 	     (compwords[cur] || pe[-1] == '=') :
 	     (state.curopt->type == CAO_EQUAL ?
@@ -2206,6 +2207,7 @@ ca_parse_line(Cadef d, Cadef all, int multi, int first)
 		state.curopt = NULL;
 	    }
 	} else if (state.opt == 2 && d->single &&
+		   (*line == '-' || *line == '+') &&
 		   ((state.curopt = ca_get_sopt(d, line, &pe, &sopts)) ||
 		    (cur != compcurrent && sopts && nonempty(sopts)))) {
 	    /* Or maybe it's a single-letter option? */