From 0882d0eda2ba7dbacdd2ce4ae0a4f212a98d379f Mon Sep 17 00:00:00 2001
From: hyung-hwan <hyunghwan.chung@gmail.com>
Date: Tue, 4 Jan 2022 14:21:14 +0000
Subject: [PATCH] added hio_rotate_uchars() and hio_rotate_bchars()

---
 hio/lib/hio-utl.h    | 15 ++++++++++
 hio/lib/hio-utl.h.m4 | 15 ++++++++++
 hio/lib/utl-str.c    | 68 ++++++++++++++++++++++++++++++++++++++++++++
 hio/lib/utl-str.c.m4 |  3 ++
 hio/lib/utl-str.m4   | 37 ++++++++++++++++++++++++
 5 files changed, 138 insertions(+)

diff --git a/hio/lib/hio-utl.h b/hio/lib/hio-utl.h
index dddee11..10146f3 100644
--- a/hio/lib/hio-utl.h
+++ b/hio/lib/hio-utl.h
@@ -511,6 +511,21 @@ HIO_EXPORT hio_bch_t* hio_find_bchar_in_bcstr (
 	hio_bch_t        c
 );
 
+HIO_EXPORT hio_oow_t hio_rotate_uchars (
+	hio_uch_t*       str,
+	hio_oow_t        len,
+	int              dir,
+	hio_oow_t        n
+);
+
+HIO_EXPORT hio_oow_t hio_rotate_bchars (
+	hio_bch_t*       str,
+	hio_oow_t        len,
+	int              dir,
+	hio_oow_t        n
+);
+
+
 HIO_EXPORT hio_uch_t* hio_trim_uchars (
 	const hio_uch_t* str,
 	hio_oow_t*       len,
diff --git a/hio/lib/hio-utl.h.m4 b/hio/lib/hio-utl.h.m4
index 363bc1d..6ab7bbc 100644
--- a/hio/lib/hio-utl.h.m4
+++ b/hio/lib/hio-utl.h.m4
@@ -511,6 +511,21 @@ HIO_EXPORT hio_bch_t* hio_find_bchar_in_bcstr (
 	hio_bch_t        c
 );
 
+HIO_EXPORT hio_oow_t hio_rotate_uchars (
+	hio_uch_t*       str,
+	hio_oow_t        len,
+	int              dir,
+	hio_oow_t        n
+);
+
+HIO_EXPORT hio_oow_t hio_rotate_bchars (
+	hio_bch_t*       str,
+	hio_oow_t        len,
+	int              dir,
+	hio_oow_t        n
+);
+
+
 HIO_EXPORT hio_uch_t* hio_trim_uchars (
 	const hio_uch_t* str,
 	hio_oow_t*       len,
diff --git a/hio/lib/utl-str.c b/hio/lib/utl-str.c
index 55afb0d..61f6be7 100644
--- a/hio/lib/utl-str.c
+++ b/hio/lib/utl-str.c
@@ -437,6 +437,74 @@ hio_bch_t* hio_find_bchar_in_bcstr (const hio_bch_t* ptr, hio_bch_t c)
 	return HIO_NULL;
 }
 
+hio_oow_t hio_rotate_uchars (hio_uch_t* str, hio_oow_t len, int dir, hio_oow_t n)
+{
+	hio_oow_t first, last, count, index, nk;
+	hio_uch_t c;
+
+	if (dir == 0 || len == 0) return len;
+	if ((n %= len) == 0) return len;
+
+	if (dir > 0) n = len - n;
+	first = 0; nk = len - n; count = 0;
+
+	while (count < n)
+	{
+		last = first + nk;
+		index = first;
+		c = str[first];
+		do
+		{
+			count++;
+			while (index < nk)
+			{
+				str[index] = str[index + n];
+				index += n;
+			}
+			if (index == last) break;
+			str[index] = str[index - nk];
+			index -= nk;
+		}
+		while (1);
+		str[last] = c; first++;
+	}
+	return len;
+}
+
+hio_oow_t hio_rotate_bchars (hio_bch_t* str, hio_oow_t len, int dir, hio_oow_t n)
+{
+	hio_oow_t first, last, count, index, nk;
+	hio_bch_t c;
+
+	if (dir == 0 || len == 0) return len;
+	if ((n %= len) == 0) return len;
+
+	if (dir > 0) n = len - n;
+	first = 0; nk = len - n; count = 0;
+
+	while (count < n)
+	{
+		last = first + nk;
+		index = first;
+		c = str[first];
+		do
+		{
+			count++;
+			while (index < nk)
+			{
+				str[index] = str[index + n];
+				index += n;
+			}
+			if (index == last) break;
+			str[index] = str[index - nk];
+			index -= nk;
+		}
+		while (1);
+		str[last] = c; first++;
+	}
+	return len;
+}
+
 hio_uch_t* hio_trim_uchars (const hio_uch_t* str, hio_oow_t* len, int flags)
 {
 	const hio_uch_t* p = str, * end = str + *len;
diff --git a/hio/lib/utl-str.c.m4 b/hio/lib/utl-str.c.m4
index 25ed1a6..b23d7f2 100644
--- a/hio/lib/utl-str.c.m4
+++ b/hio/lib/utl-str.c.m4
@@ -69,6 +69,9 @@ dnl --
 fn_find_char_in_cstr(hio_find_uchar_in_ucstr, hio_uch_t)
 fn_find_char_in_cstr(hio_find_bchar_in_bcstr, hio_bch_t)
 dnl --
+fn_rotate_chars(hio_rotate_uchars, hio_uch_t)
+fn_rotate_chars(hio_rotate_bchars, hio_bch_t)
+dnl --
 fn_trim_chars(hio_trim_uchars, hio_uch_t, hio_is_uch_space, HIO_TRIM_UCHARS)
 fn_trim_chars(hio_trim_bchars, hio_bch_t, hio_is_bch_space, HIO_TRIM_BCHARS)
 dnl --
diff --git a/hio/lib/utl-str.m4 b/hio/lib/utl-str.m4
index af333a7..abf2403 100644
--- a/hio/lib/utl-str.m4
+++ b/hio/lib/utl-str.m4
@@ -237,6 +237,43 @@ _char_type_* _fn_name_ (const _char_type_* ptr, _char_type_ c)
 popdef([[_fn_name_]])popdef([[_char_type_]])dnl
 ]])dnl
 dnl ---------------------------------------------------------------------------
+define([[fn_rotate_chars]], [[pushdef([[_fn_name_]], $1)pushdef([[_char_type_]], $2)dnl
+hio_oow_t _fn_name_ (_char_type_* str, hio_oow_t len, int dir, hio_oow_t n)
+{
+	hio_oow_t first, last, count, index, nk;
+	_char_type_ c;
+
+	if (dir == 0 || len == 0) return len;
+	if ((n %= len) == 0) return len;
+
+	if (dir > 0) n = len - n;
+	first = 0; nk = len - n; count = 0;
+
+	while (count < n)
+	{
+		last = first + nk;
+		index = first;
+		c = str[first];
+		do
+		{
+			count++;
+			while (index < nk)
+			{
+				str[index] = str[index + n];
+				index += n;
+			}
+			if (index == last) break;
+			str[index] = str[index - nk];
+			index -= nk;
+		}
+		while (1);
+		str[last] = c; first++;
+	}
+	return len;
+}
+popdef([[_fn_name_]])popdef([[_char_type_]])dnl
+]])dnl
+dnl ---------------------------------------------------------------------------
 define([[fn_trim_chars]], [[pushdef([[_fn_name_]], $1)pushdef([[_char_type_]], $2)pushdef([[_is_space_]], $3)pushdef([[_prefix_]], $4)dnl
 _char_type_* _fn_name_ (const _char_type_* str, hio_oow_t* len, int flags)
 {