Add a new flag to vis(3): VIS_GLOB which encodes the glob(3) magic

characters '*', '?' and '['.

3 files changed, 8 insertions, 2 deletions

diff --git a/include/vis.h b/include/vis.h
index d4134db..28f9765 100644
--- a/include/vis.h
+++ b/include/vis.h
@@ -65,6 +65,7 @@ typedef	__size_t	size_t;
  */
 #define	VIS_NOSLASH	0x40	/* inhibit printing '\' */
 #define	VIS_HTTPSTYLE	0x80	/* http-style escape % HEX HEX */
+#define	VIS_GLOB	0x100	/* encode glob(3) magics */
 
 /*
  * unvis return codes
diff --git a/lib/libc/gen/vis.3 b/lib/libc/gen/vis.3
index 6f685a9..25f1365 100644
--- a/lib/libc/gen/vis.3
+++ b/lib/libc/gen/vis.3
@@ -137,6 +137,9 @@ except space, tab, and newline are encoded.
 The following flags
 alter this:
 .Bl -tag -width VIS_WHITEX
+.It Dv VIS_GLOB
+Also encode magic characters ('*', '?', '[') recognized by
+.Xr glob 3
 .It Dv VIS_SP
 Also encode space.
 .It Dv VIS_TAB
diff --git a/lib/libc/gen/vis.c b/lib/libc/gen/vis.c
index 8868a70..4f594eb 100644
--- a/lib/libc/gen/vis.c
+++ b/lib/libc/gen/vis.c
@@ -71,7 +71,9 @@ vis(dst, c, flag, nextc)
 		}
 	}
 
-	if (isgraph(c) ||
+	if ((flag & VIS_GLOB) && (c == '*' || c == '?' || c == '['))
+		;
+	else if (isgraph(c) ||
 	   ((flag & VIS_SP) == 0 && c == ' ') ||
 	   ((flag & VIS_TAB) == 0 && c == '\t') ||
 	   ((flag & VIS_NL) == 0 && c == '\n') ||
@@ -127,7 +129,7 @@ vis(dst, c, flag, nextc)
 			goto done;
 		}
 	}
-	if (((c & 0177) == ' ') || (flag & VIS_OCTAL)) {
+	if (((c & 0177) == ' ') || isgraph(c) || (flag & VIS_OCTAL)) {
 		*dst++ = '\\';
 		*dst++ = ((u_char)c >> 6 & 07) + '0';
 		*dst++ = ((u_char)c >> 3 & 07) + '0';