--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/src/bit_operations.c	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,112 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * bit_operations.c - Various bit level operations, such as bit reversal
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2006 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: bit_operations.c,v 1.5 2006/11/30 15:41:47 steveu Exp $
+ */
+
+/*! \file */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <inttypes.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <string.h>
+#include <assert.h>
+#include <memory.h>
+
+#include "spandsp/telephony.h"
+#include "spandsp/bit_operations.h"
+
+uint16_t bit_reverse16(uint16_t x)
+{
+    x = (x >> 8) | (x << 8);
+    x = ((x & 0xF0F0) >> 4) | ((x & 0x0F0F) << 4);
+    x = ((x & 0xCCCC) >> 2) | ((x & 0x3333) << 2);
+    return ((x & 0xAAAA) >> 1) | ((x & 0x5555) << 1);
+}
+/*- End of function --------------------------------------------------------*/
+
+uint32_t bit_reverse32(uint32_t x)
+{
+    x = (x >> 16) | (x << 16);
+    x = ((x & 0xFF00FF00) >> 8) | ((x & 0x00FF00FF) << 8);
+    x = ((x & 0xF0F0F0F0) >> 4) | ((x & 0x0F0F0F0F) << 4);
+    x = ((x & 0xCCCCCCCC) >> 2) | ((x & 0x33333333) << 2);
+    return ((x & 0xAAAAAAAA) >> 1) | ((x & 0x55555555) << 1);
+}
+/*- End of function --------------------------------------------------------*/
+
+uint32_t bit_reverse_4bytes(uint32_t x)
+{
+    x = (x >> 4) | (x << 4);
+    x = ((x & 0xCCCCCCCC) >> 2) | ((x & 0x33333333) << 2);
+    return ((x & 0xAAAAAAAA) >> 1) | ((x & 0x55555555) << 1);
+}
+/*- End of function --------------------------------------------------------*/
+
+int one_bits32(uint32_t x)
+{
+    x = x - ((x >> 1) & 0x55555555);
+    /* We now have 16 2-bit counts */
+    x = (x & 0x33333333) + ((x >> 2) & 0x33333333);
+    /* We now have 8 4-bit counts */
+    x = (x + (x >> 4)) & 0x0F0F0F0F;
+    /* We now have 4 8-bit counts */
+#if defined(__i386__)  ||  defined(__x86_64__)
+    /* If multiply is fast */
+    return (x*0x01010101) >> 24;
+#else
+    /* If multiply is slow */
+    x += (x >> 8);
+    x += (x >> 16);
+    return (x & 0x0000003F);
+#endif
+}
+/*- End of function --------------------------------------------------------*/
+
+uint32_t make_mask32(uint32_t x)
+{
+    x |= (x >> 1);
+    x |= (x >> 2);
+    x |= (x >> 4);
+    x |= (x >> 8);
+    x |= (x >> 16);
+    return x;
+}
+/*- End of function --------------------------------------------------------*/
+
+uint16_t make_mask16(uint16_t x)
+{
+    x |= (x >> 1);
+    x |= (x >> 2);
+    x |= (x >> 4);
+    x |= (x >> 8);
+    return x;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/