From 0957fdca6ac5b41fa95f4a08d06f402e53d7e324 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Wed, 22 Apr 2020 12:22:29 +0200
Subject: [PATCH] lib/mbsalign: add function to calculate width

We already have mbs_safe_nwidth() but it assumes that all "bad" chars
will be encoded by \x<hex>. Now we need also function that do not care
about encoding.

Signed-off-by: Karel Zak <kzak@redhat.com>
---
 include/mbsalign.h |  3 +++
 lib/mbsalign.c     | 64 +++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/include/mbsalign.h b/include/mbsalign.h
index 0c28e6f69..4f5add8b8 100644
--- a/include/mbsalign.h
+++ b/include/mbsalign.h
@@ -53,6 +53,9 @@ extern size_t mbsalign_with_padding (const char *src, char *dest, size_t dest_si
 extern size_t mbs_safe_nwidth(const char *buf, size_t bufsz, size_t *sz);
 extern size_t mbs_safe_width(const char *s);
 
+extern size_t mbs_nwidth(const char *buf, size_t bufsz);
+extern size_t mbs_width(const char *s);
+
 extern char *mbs_safe_encode(const char *s, size_t *width);
 extern char *mbs_safe_encode_to_buffer(const char *s, size_t *width, char *buf, const char *safechars);
 extern size_t mbs_safe_encode_size(size_t bytes);
diff --git a/lib/mbsalign.c b/lib/mbsalign.c
index e94b277b4..e251202af 100644
--- a/lib/mbsalign.c
+++ b/lib/mbsalign.c
@@ -28,9 +28,67 @@
 #include "strutils.h"
 #include "widechar.h"
 
-/* Replace non printable chars.
-   Note \t and \n etc. are non printable.
-   Return 1 if replacement made, 0 otherwise.  */
+/*
+ * Counts number of cells in multibyte string. All control and
+ * non-printable chars are ignored.
+ *
+ * Returns: number of cells.
+ */
+size_t mbs_nwidth(const char *buf, size_t bufsz)
+{
+	const char *p = buf, *last = buf;
+	size_t width = 0;
+
+#ifdef HAVE_WIDECHAR
+	mbstate_t st;
+	memset(&st, 0, sizeof(st));
+#endif
+	if (p && *p && bufsz)
+		last = p + (bufsz - 1);
+
+	while (p && *p && p <= last) {
+		if (iscntrl((unsigned char) *p)) {
+			p++;
+
+			/* try detect "\e[x;ym" and skip on success */
+			if (*p && *p == '[') {
+				const char *e = p;
+				while (*e && e < last && *e != 'm')
+					e++;
+				if (*e == 'm')
+					p = e + 1;
+			}
+			continue;
+		}
+#ifdef HAVE_WIDECHAR
+		wchar_t wc;
+		size_t len = mbrtowc(&wc, p, MB_CUR_MAX, &st);
+
+		if (len == 0)
+			break;
+		if (len > 0 && iswprint(wc)) {
+			int x = wcwidth(wc);
+			if (x > 0)
+				width += x;
+		} else if (len == (size_t) -1 || len == (size_t) -2)
+			len = 1;
+		p += len;
+#else
+		if (isprint((unsigned char) *p))
+			width++;
+		p++;
+#endif
+	}
+
+	return width;
+}
+
+size_t mbs_width(const char *s)
+{
+	if (!s || !*s)
+		return 0;
+	return mbs_nwidth(s, strlen(s));
+}
 
 /*
  * Counts number of cells in multibyte string. For all control and