1 files changed, 123 insertions, 0 deletions
diff --git a/comm/third_party/libgcrypt/cipher/bithelp.h b/comm/third_party/libgcrypt/cipher/bithelp.h
new file mode 100644
index 0000000000..7793ce7ca3
--- /dev/null
+++ b/comm/third_party/libgcrypt/cipher/bithelp.h
@@ -0,0 +1,123 @@
+/* bithelp.h  -  Some bit manipulation helpers
+ *	Copyright (C) 1999, 2002 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef GCRYPT_BITHELP_H
+#define GCRYPT_BITHELP_H
+
+#include "types.h"
+
+
+/****************
+ * Rotate the 32 bit unsigned integer X by N bits left/right
+ */
+static inline u32 rol(u32 x, int n)
+{
+	return ( (x << (n&(32-1))) | (x >> ((32-n)&(32-1))) );
+}
+
+static inline u32 ror(u32 x, int n)
+{
+	return ( (x >> (n&(32-1))) | (x << ((32-n)&(32-1))) );
+}
+
+static inline u64 rol64(u64 x, int n)
+{
+  return ( (x << (n&(64-1))) | (x >> ((64-n)&(64-1))) );
+}
+
+/* Byte swap for 32-bit and 64-bit integers.  If available, use compiler
+   provided helpers.  */
+#ifdef HAVE_BUILTIN_BSWAP32
+# define _gcry_bswap32 __builtin_bswap32
+#else
+static inline u32
+_gcry_bswap32(u32 x)
+{
+	return ((rol(x, 8) & 0x00ff00ffL) | (ror(x, 8) & 0xff00ff00L));
+}
+#endif
+
+#ifdef HAVE_BUILTIN_BSWAP64
+# define _gcry_bswap64 __builtin_bswap64
+#else
+static inline u64
+_gcry_bswap64(u64 x)
+{
+	return ((u64)_gcry_bswap32(x) << 32) | (_gcry_bswap32(x >> 32));
+}
+#endif
+
+/* Endian dependent byte swap operations.  */
+#ifdef WORDS_BIGENDIAN
+# define le_bswap32(x) _gcry_bswap32(x)
+# define be_bswap32(x) ((u32)(x))
+# define le_bswap64(x) _gcry_bswap64(x)
+# define be_bswap64(x) ((u64)(x))
+#else
+# define le_bswap32(x) ((u32)(x))
+# define be_bswap32(x) _gcry_bswap32(x)
+# define le_bswap64(x) ((u64)(x))
+# define be_bswap64(x) _gcry_bswap64(x)
+#endif
+
+
+/* Count trailing zero bits in an unsigend int.  We return an int
+   because that is what gcc's builtin does.  Returns the number of
+   bits in X if X is 0. */
+static inline int
+_gcry_ctz (unsigned int x)
+{
+#if defined (HAVE_BUILTIN_CTZ)
+  return x ? __builtin_ctz (x) : 8 * sizeof (x);
+#else
+  /* See
+   * http://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightModLookup
+   */
+  static const unsigned char mod37[] =
+    {
+      sizeof (unsigned int)*8,
+          0,  1, 26,  2, 23, 27,  0,  3, 16, 24, 30, 28, 11,  0, 13,
+      4,  7, 17,  0, 25, 22, 31, 15, 29, 10, 12,  6,  0, 21, 14,  9,
+      5, 20,  8, 19, 18
+    };
+  return (int)mod37[(-x & x) % 37];
+#endif
+}
+
+
+/* Count trailing zero bits in an u64.  We return an int because that
+   is what gcc's builtin does.  Returns the number of bits in X if X
+   is 0.  */
+static inline int
+_gcry_ctz64(u64 x)
+{
+#if defined (HAVE_BUILTIN_CTZL) && SIZEOF_UNSIGNED_LONG >= 8
+  return x ? __builtin_ctzl (x) : 8 * sizeof (x);
+#elif defined (HAVE_BUILTIN_CTZ) && SIZEOF_UNSIGNED_INT >= 8
+#warning hello
+  return x ? __builtin_ctz (x) : 8 * sizeof (x);
+#else
+  if ((x & 0xffffffff))
+    return _gcry_ctz (x);
+  else
+    return 32 + _gcry_ctz (x >> 32);
+#endif
+}
+
+
+#endif /*GCRYPT_BITHELP_H*/