1 files changed, 61 insertions, 0 deletions
diff --git a/src/usr.bin/rs/utf8.c b/src/usr.bin/rs/utf8.c
new file mode 100644
index 0000000..c779d74
--- /dev/null
+++ b/src/usr.bin/rs/utf8.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2015 Ingo Schwarze <schwarze@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <err.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wchar.h>
+
+int
+mbsavis(char** outp, const char *mbs)
+{
+	const char *src;  /* Iterate mbs. */
+	char	 *dst;  /* Iterate *outp. */
+	wchar_t	  wc;
+	int	  total_width;  /* Display width of the whole string. */
+	int	  width;  /* Display width of a single Unicode char. */
+	int	  len;  /* Length in bytes of UTF-8 encoded string. */
+
+	len = strlen(mbs);
+	if ((*outp = malloc(len + 1)) == NULL)
+		err(1, NULL);
+
+	if (MB_CUR_MAX == 1) {
+		memcpy(*outp, mbs, len + 1);
+		return len;
+	}
+
+	src = mbs;
+	dst = *outp;
+	total_width = 0;
+	while (*src != '\0') {
+		if ((len = mbtowc(&wc, src, MB_CUR_MAX)) == -1) {
+			total_width++;
+			*dst++ = '?';
+			src++;
+		} else if ((width = wcwidth(wc)) == -1) {
+			total_width++;
+			*dst++ = '?';
+			src += len;
+		} else {
+			total_width += width;
+			while (len-- > 0)
+				*dst++ = *src++;
+		}
+	}
+	*dst = '\0';
+	return total_width;
+}