1 files changed, 129 insertions, 0 deletions
diff --git a/lib/Base85.cc b/lib/Base85.cc
new file mode 100644
index 0000000..d8722fb
--- /dev/null
+++ b/lib/Base85.cc
@@ -0,0 +1,129 @@
+/*
+ *  Baltisot
+ *  Copyright (C) 1999-2009 Nicolas "Pixel" Noble
+ *
+ *  This program 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
+ *  (at your option) any later version.
+ *
+ *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <Base85.h>
+
+String Base85::encode_block(unsigned char in_tab[4], int len) {
+    unsigned int tuple;
+    char r[6];
+    
+    tuple  = in_tab[0];
+    tuple |= in_tab[1] <<  8;
+    tuple |= in_tab[2] << 16;
+    tuple |= in_tab[3] << 24;
+    
+    r[0] = (tuple % 85) + '!';
+    tuple /= 85;
+    r[1] = (tuple % 85) + '!';
+    tuple /= 85;
+    r[2] = len > 1 ? (tuple % 85) + '!' : '~';
+    tuple /= 85;
+    r[3] = len > 2 ? (tuple % 85) + '!' : '~';
+    tuple /= 85;
+    r[4] = len > 3 ? (tuple % 85) + '!' : '~';
+    r[5] = 0;
+    
+    return r;
+}
+
+String Base85::encode(const char * data, int stream_size) {
+    String encoded = "";
+    unsigned char in_tab[4];
+    int len, i, s_pos;
+
+    s_pos = 0;
+
+    while (stream_size > 0) {
+        in_tab[0] = 0;
+        in_tab[1] = 0;
+        in_tab[2] = 0;
+        in_tab[3] = 0;
+
+        len = stream_size >= 4 ? 4 : stream_size;
+
+        for (i = 0; i < len; i++) {
+            in_tab[i] = data[s_pos + i];
+        }
+
+        encoded += encode_block(in_tab, len);
+
+        s_pos += 4;
+        stream_size -= 4;
+    }
+
+    return encoded;
+}
+
+int Base85::decode_block(char s1, char s2, char s3, char s4, char s5, unsigned char * out_tab) {
+    int len, sb1, sb2, sb3, sb4, sb5;
+    unsigned int tuple;
+
+    len = s3 == '~' ? 1 : s4 == '~' ? 2 : s5 == '~' ? 3 : 4;
+    s3 = (s3 == '~') || (s3 == 0) ? '!' : s3;
+    s4 = (s4 == '~') || (s4 == 0) ? '!' : s4;
+    s5 = (s5 == '~') || (s5 == 0) ? '!' : s5;
+    
+    sb1 = s1 - '!';
+    sb2 = s2 - '!';
+    sb3 = s3 - '!';
+    sb4 = s4 - '!';
+    sb5 = s5 - '!';
+    
+    tuple  = s5; tuple *= 85;
+    tuple |= s4; tuple *= 85;
+    tuple |= s3; tuple *= 85;
+    tuple |= s2; tuple *= 85;
+    tuple |= s1;
+    
+    out_tab[0] = tuple & 255; tuple >>= 8;
+    out_tab[1] = tuple & 255; tuple >>= 8;
+    out_tab[2] = tuple & 255; tuple >>= 8;
+    out_tab[3] = tuple & 255;
+    
+    return len;
+}
+
+unsigned char * Base85::decode(const String & str_in, int * len_out) {
+    int s_len = str_in.strlen(), len = 0, i, j, t_len;
+    char s1, s2, s3, s4, s5;
+    unsigned char t_out[4];
+    unsigned char * out = (unsigned char *) malloc(s_len * 4 / 5 + 5);
+    unsigned char * p = out;
+    
+    for (i = 0; i < s_len; i += 5) {
+        s1 = str_in[i + 0];
+        s2 = str_in[i + 1];
+        s3 = str_in[i + 2];
+        s4 = str_in[i + 3];
+        s5 = str_in[i + 4];
+        t_len = decode_block(s1, s2, s3, s4, s5, t_out);
+        
+        for (j = 0; j < t_len; j++) {
+            *(p++) = t_out[j];
+        }
+
+        len += t_len;
+    }
+    
+    if (len_out) {
+        *len_out = len;
+    }
+
+    return out;
+}