ENH: Initial import of Base64

1 files changed, 262 insertions, 0 deletions

diff --git a/Source/kwsys/Base64.c b/Source/kwsys/Base64.c
new file mode 100644
index 0000000..cdb0675
--- /dev/null
+++ b/Source/kwsys/Base64.c
@@ -0,0 +1,262 @@
+/*=========================================================================
+
+Program:   KWSys - Kitware System Library
+Module:    $RCSfile$
+Language:  C++
+Date:      $Date$
+Version:   $Revision$
+
+Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
+See http://www.cmake.org/HTML/Copyright.html for details.
+
+This software is distributed WITHOUT ANY WARRANTY; without even 
+the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
+PURPOSE.  See the above copyright notices for more information.
+
+=========================================================================*/
+#define KWSYS_IN_PROCESS_C
+#include <Base64.h>
+
+/*--------------------------------------------------------------------------*/
+static const unsigned char kwsysBase64EncodeTable[65] =
+"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+"abcdefghijklmnopqrstuvwxyz"
+"0123456789+/";
+
+/*--------------------------------------------------------------------------*/
+static const unsigned char kwsysBase64DecodeTable[256] =
+{
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0x3E,0xFF,0xFF,0xFF,0x3F,
+  0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,
+  0x3C,0x3D,0xFF,0xFF,0xFF,0x00,0xFF,0xFF,
+  0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06,
+  0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,
+  0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,
+  0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,
+  0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,
+  0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,
+  0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF,
+  /*------------------------------------*/
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
+};
+
+/*--------------------------------------------------------------------------*/
+static unsigned char kwsysBase64EncodeChar(unsigned char c)
+{
+  return kwsysBase64EncodeTable[c];
+}
+
+/*--------------------------------------------------------------------------*/
+static unsigned char kwsysBase64DecodeChar(unsigned char c)
+{
+  return kwsysBase64DecodeTable[c];
+}
+
+/*--------------------------------------------------------------------------*/
+/* Encode 3 bytes into a 4 byte string. */
+void kwsysBase64_Encode3(const unsigned char *src, unsigned char *dest)
+{
+  dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F);
+  dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30)|((src[1] >> 4) & 0x0F));
+  dest[2] = kwsysBase64EncodeChar(((src[1] << 2) & 0x3C)|((src[2] >> 6) & 0x03));
+  dest[3] = kwsysBase64EncodeChar(src[2] & 0x3F);
+}
+
+/*--------------------------------------------------------------------------*/
+/* Encode 2 bytes into a 4 byte string. */
+void kwsysBase64_Encode2(const unsigned char *src, unsigned char *dest)
+{
+  dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F);
+  dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30)|((src[1] >> 4) & 0x0F));
+  dest[2] = kwsysBase64EncodeChar(((src[1] << 2) & 0x3C)|((src[2] >> 6) & 0x03));
+  dest[3] = '=';
+}
+
+/*--------------------------------------------------------------------------*/
+/* Encode 1 bytes into a 4 byte string. */
+void kwsysBase64_Encode1(const unsigned char *src, unsigned char *dest)
+{
+  dest[0] = kwsysBase64EncodeChar((src[0] >> 2) & 0x3F);
+  dest[1] = kwsysBase64EncodeChar(((src[0] << 4) & 0x30));
+  dest[2] = '=';
+  dest[3] = '=';
+}
+
+/*--------------------------------------------------------------------------*/
+/* Encode 'length' bytes from the input buffer and store the
+   encoded stream into the output buffer. Return the length of the encoded
+   buffer (output). Note that the output buffer must be allocated by the caller
+   (length * 1.5 should be a safe estimate).  If 'mark_end' is true than an
+   extra set of 4 bytes is added to the end of the stream if the input is a
+   multiple of 3 bytes.  These bytes are invalid chars and therefore they will
+   stop the decoder thus enabling the caller to decode a stream without
+   actually knowing how much data to expect (if the input is not a multiple of
+   3 bytes then the extra padding needed to complete the encode 4 bytes will
+   stop the decoding anyway).  */
+unsigned long kwsysBase64_Encode(const unsigned char *input,
+  unsigned long length, unsigned char *output, int mark_end)
+{
+  const unsigned char *ptr = input;
+  const unsigned char *end = input + length;
+  unsigned char *optr = output;
+
+  /* Encode complete triplet */
+
+  while ((end - ptr) >= 3)
+    {
+    kwsysBase64_Encode3(ptr, optr);
+    ptr += 3;
+    optr += 4;
+    }
+
+  /* Encodes a 2-byte ending into 3 bytes and 1 pad byte and writes. */
+
+  if (end - ptr == 2)
+    {
+    kwsysBase64_Encode2(ptr, optr);
+    optr += 4;
+    }
+
+  /* Encodes a 1-byte ending into 2 bytes and 2 pad bytes */
+  
+  else if (end - ptr == 1)
+    {
+    kwsysBase64_Encode1(ptr, optr);
+    optr += 4;
+    }
+
+  /* Do we need to mark the end */
+
+  else if (mark_end)
+    {
+    optr[0] = optr[1] = optr[2] = optr[3] = '=';
+    optr += 4;
+    }
+
+  return optr - output;
+}
+/*--------------------------------------------------------------------------*/
+/* Decode 4 bytes into a 3 byte string. */
+int kwsysBase64_Decode3(const unsigned char *src, unsigned char *dest)
+{
+  unsigned char d0, d1, d2, d3;
+
+  d0 = kwsysBase64DecodeChar(src[0]);
+  d1 = kwsysBase64DecodeChar(src[1]);
+  d2 = kwsysBase64DecodeChar(src[2]);
+  d3 = kwsysBase64DecodeChar(src[3]);
+  
+  /* Make sure all characters were valid */
+
+  if (d0 == 0xFF || d1 == 0xFF || d2 == 0xFF || d3 == 0xFF)
+    { 
+    return 0; 
+    }
+  
+  /* Decode the 3 bytes */
+
+  dest[0] = ((d0 << 2) & 0xFC) | ((d1 >> 4) & 0x03);
+  dest[1] = ((d1 << 4) & 0xF0) | ((d2 >> 2) & 0x0F);
+  dest[2] = ((d2 << 6) & 0xC0) | ((d3 >> 0) & 0x3F);
+  
+  /* Return the number of bytes actually decoded */
+
+  if (src[2] == '=') 
+    { 
+    return 1; 
+    }
+  if (src[3] == '=') 
+    { 
+    return 2; 
+    }
+  return 3;
+}
+
+/*--------------------------------------------------------------------------*/
+/* Decode bytes from the input buffer and store the decoded stream 
+   into the output buffer until 'length' bytes have been decoded.  Return the
+   real length of the decoded stream (which should be equal to 'length'). Note
+   that the output buffer must be allocated by the caller.  If
+   'max_input_length' is not null, then it specifies the number of encoded
+   bytes that should be at most read from the input buffer. In that case the
+   'length' parameter is ignored. This enables the caller to decode a stream
+   without actually knowing how much decoded data to expect (of course, the
+   buffer must be large enough). */
+unsigned long kwsysBase64_Decode(const unsigned char *input, 
+  unsigned long length, unsigned char *output, unsigned long max_input_length)
+{
+  const unsigned char *ptr = input;
+  unsigned char *optr = output;
+
+  /* Decode complete triplet */
+
+  if (max_input_length)
+    {
+    const unsigned char *end = input + max_input_length;
+    while (ptr < end)
+      {
+      int len = kwsysBase64_Decode3(ptr, optr);
+      optr += len;
+      if(len < 3)
+        {
+        return optr - output;
+        }
+      ptr += 4;
+      }
+    } 
+  else 
+    {
+    unsigned char *oend = output + length;
+    while ((oend - optr) >= 3)
+      {
+      int len = kwsysBase64_Decode3(ptr, optr);
+      optr += len;
+      if(len < 3)
+        {
+        return optr - output;
+        }
+      ptr += 4;
+      }
+
+    /* Decode the last triplet */
+  
+    if (oend - optr == 2)
+      {
+      unsigned char temp[3];
+      int len = kwsysBase64_Decode3(ptr, temp);
+      optr[0] = temp[0];
+      optr[1] = temp[1];
+      optr += (len > 2 ? 2 : len); 
+      }
+    else if (oend - optr == 1)
+      {
+      unsigned char temp[3];
+      int len = kwsysBase64_Decode3(ptr, temp);
+      optr[0] = temp[0];
+      optr += (len > 2 ? 2 : len); 
+      }
+    }
+
+  return optr - output;
+}