glitch in the license text detected by hyazinthe, thank you!

[oweals/gnunet.git] / src / util / crypto_crc.c

diff --git a/src/util/crypto_crc.c b/src/util/crypto_crc.c
index 3f499135343fda1ed2ed09b07519e73b218a54f4..12cb169e8746c2baf4e46d94be3016bfbc7f5760 100644 (file)
--- a/src/util/crypto_crc.c
+++ b/src/util/crypto_crc.c
@@ -1,21 +1,16 @@
 /*
      This file is part of GNUnet.
-     (C) 2001, 2002, 2003, 2004, 2006 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2001, 2002, 2003, 2004, 2006 GNUnet e.V.
 
-     GNUnet is free software; you can redistribute it and/or modify
-     it under the terms of the GNU General Public License as published
-     by the Free Software Foundation; either version 2, or (at your
-     option) any later version.
+     GNUnet is free software: you can redistribute it and/or modify it
+     under the terms of the GNU Affero General Public License as published
+     by the Free Software Foundation, either version 3 of the License,
+     or (at your option) any later version.
 
      GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
-     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
+     Affero General Public License for more details.
 
      For the actual CRC-32 code:
      Copyright abandoned; this code is in the public domain.
@@ -27,18 +22,16 @@
  * @brief implementation of CRC16 and CRC32
  * @author Christian Grothoff
  */
-
 #include "platform.h"
-#include "gnunet_common.h"
 #include "gnunet_crypto_lib.h"
 
-#define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
+#define LOG(kind,...) GNUNET_log_from (kind, "util-crypto-crc", __VA_ARGS__)
 
 /* Avoid wasting space on 8-byte longs. */
 #if UINT_MAX >= 0xffffffff
-typedef unsigned int uLong;
+typedef unsigned int GNUNET_uLong;
 #elif ULONG_MAX >= 0xffffffff
-typedef unsigned long uLong;
+typedef unsigned long GNUNET_uLong;
 #else
 #error This compiler is not ANSI-compliant!
 #endif
@@ -46,8 +39,8 @@ typedef unsigned long uLong;
 #define Z_NULL  0
 
 
-#define POLYNOMIAL (uLong)0xedb88320
-static uLong crc_table[256];
+#define POLYNOMIAL (GNUNET_uLong)0xedb88320
+static GNUNET_uLong crc_table[256];
 
 /*
  * This routine writes each crc_table entry exactly once,
@@ -59,7 +52,7 @@ crc_init ()
 {
   static int once;
   unsigned int i, j;
-  uLong h = 1;
+  GNUNET_uLong h = 1;
 
   if (once)
     return;
@@ -84,8 +77,8 @@ crc_init ()
  * to data in little-endian byte and bit order to preserve the
  * property of detecting all burst errors of length 32 bits or less.
  */
-static uLong
-crc32 (uLong crc, const char *buf, size_t len)
+static GNUNET_uLong
+crc32 (GNUNET_uLong crc, const char *buf, size_t len)
 {
   crc_init ();
   GNUNET_assert (crc_table[255] != 0);
@@ -106,7 +99,7 @@ crc32 (uLong crc, const char *buf, size_t len)
 int32_t
 GNUNET_CRYPTO_crc32_n (const void *buf, size_t len)
 {
-  uLong crc;
+  GNUNET_uLong crc;
 
   crc = crc32 (0L, Z_NULL, 0);
   crc = crc32 (crc, (char *) buf, len);
@@ -120,7 +113,7 @@ GNUNET_CRYPTO_crc32_n (const void *buf, size_t len)
  * @param sum current sum, initially 0
  * @param buf buffer to calculate CRC over (must be 16-bit aligned)
  * @param len number of bytes in hdr, must be multiple of 2
- * @return updated crc sum (must be subjected to GNUNET_CRYPTO_crc16_finish to get actual crc16)
+ * @return updated crc sum (must be subjected to #GNUNET_CRYPTO_crc16_finish() to get actual crc16)
  */
 uint32_t
 GNUNET_CRYPTO_crc16_step (uint32_t sum, const void *buf, size_t len)
@@ -135,7 +128,7 @@ GNUNET_CRYPTO_crc16_step (uint32_t sum, const void *buf, size_t len)
 
 
 /**
- * Convert results from GNUNET_CRYPTO_crc16_step to final crc16.
+ * Convert results from #GNUNET_CRYPTO_crc16_step() to final crc16.
  *
  * @param sum cummulative sum
  * @return crc16 value
@@ -167,5 +160,35 @@ GNUNET_CRYPTO_crc16_n (const void *buf, size_t len)
 }
 
 
+/**
+ * @ingroup hash
+ * Calculate the checksum of a buffer in one step.
+ *
+ * @param buf buffer to calculate CRC over
+ * @param len number of bytes in @a buf
+ * @return crc8 value
+ */
+uint8_t
+GNUNET_CRYPTO_crc8_n (const void *buf,
+                      size_t len)
+{
+  const uint8_t *data = buf;
+  unsigned int crc = 0;
+  int i;
+  int j;
+
+  for (j = len; 0 != j; j--)
+  {
+    crc ^= (*data++ << 8);
+    for (i = 8; 0 != i; i--)
+    {
+      if (0 != (crc & 0x8000))
+        crc ^= (0x1070 << 3);
+      crc <<= 1;
+    }
+  }
+  return (uint8_t) (crc >> 8);
+}
+
 
 /* end of crypto_crc.c */