1 files changed, 120 insertions, 0 deletions
diff --git a/usr.bin/less/cvt.c b/usr.bin/less/cvt.c
new file mode 100644
index 00000000000..74439847e01
--- /dev/null
+++ b/usr.bin/less/cvt.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 1984-2011  Mark Nudelman
+ *
+ * You may distribute under the terms of either the GNU General Public
+ * License or the Less License, as specified in the README file.
+ *
+ * For more information about less, or for information on how to 
+ * contact the author, see the README file.
+ */
+
+/*
+ * Routines to convert text in various ways.  Used by search.
+ */
+
+#include "less.h"
+#include "charset.h"
+
+extern int utf_mode;
+
+/*
+ * Get the length of a buffer needed to convert a string.
+ */
+	public int
+cvt_length(len, ops)
+	int len;
+	int ops;
+{
+	if (utf_mode)
+		/*
+		 * Just copying a string in UTF-8 mode can cause it to grow 
+		 * in length.
+		 * Four output bytes for one input byte is the worst case.
+		 */
+		len *= 4;
+	return (len + 1);
+}
+
+/*
+ * Allocate a chpos array for use by cvt_text.
+ */
+	public int *
+cvt_alloc_chpos(len)
+	int len;
+{
+	int i;
+	int *chpos = (int *) ecalloc(sizeof(int), len);
+	/* Initialize all entries to an invalid position. */
+	for (i = 0;  i < len;  i++)
+		chpos[i] = -1;
+	return (chpos);
+}
+
+/*
+ * Convert text.  Perform the transformations specified by ops.
+ * Returns converted text in odst.  The original offset of each
+ * odst character (when it was in osrc) is returned in the chpos array.
+ */
+	public void
+cvt_text(odst, osrc, chpos, lenp, ops)
+	char *odst;
+	char *osrc;
+	int *chpos;
+	int *lenp;
+	int ops;
+{
+	char *dst;
+	char *src;
+	register char *src_end;
+	LWCHAR ch;
+
+	if (lenp != NULL)
+		src_end = osrc + *lenp;
+	else
+		src_end = osrc + strlen(osrc);
+
+	for (src = osrc, dst = odst;  src < src_end;  )
+	{
+		int src_pos = src - osrc;
+		int dst_pos = dst - odst;
+		ch = step_char(&src, +1, src_end);
+		if ((ops & CVT_BS) && ch == '\b' && dst > odst)
+		{
+			/* Delete backspace and preceding char. */
+			do {
+				dst--;
+			} while (dst > odst &&
+				!IS_ASCII_OCTET(*dst) && !IS_UTF8_LEAD(*dst));
+		} else if ((ops & CVT_ANSI) && IS_CSI_START(ch))
+		{
+			/* Skip to end of ANSI escape sequence. */
+			src++;  /* skip the CSI start char */
+			while (src < src_end)
+				if (!is_ansi_middle(*src++))
+					break;
+		} else
+		{
+			/* Just copy the char to the destination buffer. */
+			if ((ops & CVT_TO_LC) && IS_UPPER(ch))
+				ch = TO_LOWER(ch);
+			put_wchar(&dst, ch);
+			/*
+			 * Record the original position of the char.
+			 * But if we've already recorded a position
+			 * for this char (due to a backspace), leave
+			 * it alone; if multiple source chars map to
+			 * one destination char, we want the position
+			 * of the first one.
+			 */
+			if (chpos != NULL && chpos[dst_pos] < 0)
+				chpos[dst_pos] = src_pos;
+		}
+	}
+	if ((ops & CVT_CRLF) && dst > odst && dst[-1] == '\r')
+		dst--;
+	*dst = '\0';
+	if (lenp != NULL)
+		*lenp = dst - odst;
+	if (chpos != NULL)
+		chpos[dst - odst] = src - osrc;
+}