1 files changed, 148 insertions, 0 deletions
diff --git a/lib/ext2fs/bitops.c b/lib/ext2fs/bitops.c
new file mode 100644
index 0000000..ce2acc4
--- /dev/null
+++ b/lib/ext2fs/bitops.c
@@ -0,0 +1,148 @@
+/*
+ * bitops.c --- Bitmap frobbing code.  See bitops.h for the inlined
+ * 	routines.
+ *
+ * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#include "config.h"
+#include <stdio.h>
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+/*
+ * C language bitmap functions written by Theodore Ts'o, 9/26/92.
+ * Modified by Pete A. Zaitcev 7/14/95 to be portable to big endian
+ * systems, as well as non-32 bit systems.
+ */
+
+int ext2fs_set_bit(unsigned int nr,void * addr)
+{
+	int		mask, retval;
+	unsigned char	*ADDR = (unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	retval = mask & *ADDR;
+	*ADDR |= mask;
+	return retval;
+}
+
+int ext2fs_clear_bit(unsigned int nr, void * addr)
+{
+	int		mask, retval;
+	unsigned char	*ADDR = (unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	retval = mask & *ADDR;
+	*ADDR &= ~mask;
+	return retval;
+}
+
+int ext2fs_test_bit(unsigned int nr, const void * addr)
+{
+	int			mask;
+	const unsigned char	*ADDR = (const unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	return (mask & *ADDR);
+}
+
+void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg,
+			const char *description)
+{
+#ifndef OMIT_COM_ERR
+	if (description)
+		com_err(0, errcode, "#%lu for %s", arg, description);
+	else
+		com_err(0, errcode, "#%lu", arg);
+#endif
+}
+
+/* Bitmap functions that take a 64-bit offset */
+
+int ext2fs_set_bit64(__u64 nr, void * addr)
+{
+	int		mask, retval;
+	unsigned char	*ADDR = (unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	retval = mask & *ADDR;
+	*ADDR |= mask;
+	return retval;
+}
+
+int ext2fs_clear_bit64(__u64 nr, void * addr)
+{
+	int		mask, retval;
+	unsigned char	*ADDR = (unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	retval = mask & *ADDR;
+	*ADDR &= ~mask;
+	return retval;
+}
+
+int ext2fs_test_bit64(__u64 nr, const void * addr)
+{
+	int			mask;
+	const unsigned char	*ADDR = (const unsigned char *) addr;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	return (mask & *ADDR);
+}
+
+static unsigned int popcount8(unsigned int w)
+{
+	unsigned int res = w - ((w >> 1) & 0x55);
+	res = (res & 0x33) + ((res >> 2) & 0x33);
+	return (res + (res >> 4)) & 0x0F;
+}
+
+static unsigned int popcount32(unsigned int w)
+{
+	unsigned int res = w - ((w >> 1) & 0x55555555);
+	res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
+	res = (res + (res >> 4)) & 0x0F0F0F0F;
+	res = res + (res >> 8);
+	return (res + (res >> 16)) & 0x000000FF;
+}
+
+unsigned int ext2fs_bitcount(const void *addr, unsigned int nbytes)
+{
+	const unsigned char *cp = addr;
+	const __u32 *p;
+	unsigned int res = 0;
+
+	while (((((uintptr_t) cp) & 3) != 0) && (nbytes > 0)) {
+		res += popcount8(*cp++);
+		nbytes--;
+	}
+	p = (const __u32 *) cp;
+
+	while (nbytes > 4) {
+		res += popcount32(*p++);
+		nbytes -= 4;
+	}
+	cp = (const unsigned char *) p;
+
+	while (nbytes > 0) {
+		res += popcount8(*cp++);
+		nbytes--;
+	}
+	return res;
+}