Added base64 encoding and decoding code.

1 files changed, 104 insertions, 0 deletions

diff --git a/src/base64.cpp b/src/base64.cpp
new file mode 100644
index 00000000..57f2c9bb
--- /dev/null
+++ b/src/base64.cpp
@@ -0,0 +1,104 @@
+/*
+ *  This file 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 of the License, or
+ *  any later version.
+ *
+ *  This file 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 file; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *  $Id$
+ */
+
+#include "base64.h"
+#include <ctype.h>
+
+static const char base64digits[] =
+"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+#define BAD     -1
+
+static const char base64val[] = {
+    BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+    BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD,
+    BAD,BAD,BAD,BAD, BAD,BAD,BAD,BAD, BAD,BAD,BAD, 62, BAD,BAD,BAD, 63,
+    52,  53, 54, 55,  56, 57, 58, 59,  60, 61,BAD,BAD, BAD,BAD,BAD,BAD,
+    BAD,  0,  1,  2,   3,  4,  5,  6,   7,  8,  9, 10,  11, 12, 13, 14,
+    15,  16, 17, 18,  19, 20, 21, 22,  23, 24, 25,BAD, BAD,BAD,BAD,BAD,
+    BAD, 26, 27, 28,  29, 30, 31, 32,  33, 34, 35, 36,  37, 38, 39, 40,
+    41,  42, 43, 44,  45, 46, 47, 48,  49, 50, 51,BAD, BAD,BAD,BAD,BAD
+};
+
+#define DECODE64(c)  (isascii(c) ? base64val[c] : BAD)
+
+void to64frombits(unsigned char *out, const unsigned char *in, int inlen)
+{
+    for (; inlen >= 3; inlen -= 3)
+    {
+        *out++ = base64digits[in[0] >> 2];
+        *out++ = base64digits[((in[0] << 4) & 0x30) | (in[1] >> 4)];
+        *out++ = base64digits[((in[1] << 2) & 0x3c) | (in[2] >> 6)];
+        *out++ = base64digits[in[2] & 0x3f];
+        in += 3;
+    }
+    if (inlen > 0)
+    {
+        unsigned char fragment;
+
+        *out++ = base64digits[in[0] >> 2];
+        fragment = (in[0] << 4) & 0x30;
+        if (inlen > 1)
+            fragment |= in[1] >> 4;
+        *out++ = base64digits[fragment];
+        *out++ = (inlen < 2) ? '=' : base64digits[(in[1] << 2) & 0x3c];
+        *out++ = '=';
+    }
+    *out = '\0';
+}
+
+int from64tobits(char *out, const char *in)
+{
+    int len = 0;
+    register unsigned char digit1, digit2, digit3, digit4;
+
+    if (in[0] == '+' && in[1] == ' ')
+        in += 2;
+    if (*in == '\r')
+        return(0);
+
+    do {
+        digit1 = in[0];
+        if (DECODE64(digit1) == BAD)
+            return(-1);
+        digit2 = in[1];
+        if (DECODE64(digit2) == BAD)
+            return(-1);
+        digit3 = in[2];
+        if (digit3 != '=' && DECODE64(digit3) == BAD)
+            return(-1); 
+        digit4 = in[3];
+        if (digit4 != '=' && DECODE64(digit4) == BAD)
+            return(-1);
+        in += 4;
+        *out++ = (DECODE64(digit1) << 2) | (DECODE64(digit2) >> 4);
+        ++len;
+        if (digit3 != '=')
+        {
+            *out++ = ((DECODE64(digit2) << 4) & 0xf0) | (DECODE64(digit3) >> 2);
+            ++len;
+            if (digit4 != '=')
+            {
+                *out++ = ((DECODE64(digit3) << 6) & 0xc0) | DECODE64(digit4);
+                ++len;
+            }
+        }
+    } while (*in && *in != '\r' && digit4 != '=');
+
+    return (len);
+}