From Johannes Scholz, "Attached you find a patch for osgDB::OutputStream and osgDB::InputStream to include osg::Image::data() using Base64 encoding inside the ASCII OSGT, if WriteImageHint=IncludeData is set, only."

git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@14748 16af8721-9629-0410-8352-f15c8da7e697
2015-03-02 12:11:43 +00:00
parent 1d9e7f144b
commit 58edd10d04
5 changed files with 514 additions and 0 deletions
--- a/src/osgDB/ConvertBase64.cpp
+++ b/src/osgDB/ConvertBase64.cpp
@@ -0,0 +1,326 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
+ *
+ * This library is open source and may be redistributed and/or modified under
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ *
+ * This library 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
+ * OpenSceneGraph Public License for more details.
+*/
+
+/* This file is derived from the libb64 project which itself was released to public domain.
+ * For details, see http://sourceforge.net/projects/libb64. Original code by Chris Venter
+ * c++ wrapper for a base64 encoding and decoding algorithm
+*/
+
+#include <osgDB/ConvertBase64>
+
+#include <sstream>
+#include <string.h>
+
+namespace osgDB
+{
+
+    const int CHARS_PER_LINE = 72;
+
+    int base64_decode_value(char value_in)
+    {
+        static const char decoding[] = {62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-2,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51};
+        static const char decoding_size = sizeof(decoding);
+        value_in -= 43;
+        if (value_in < 0 || value_in > decoding_size) return -1;
+        return decoding[(int)value_in];
+    }
+
+    void base64_init_decodestate(base64_decodestate* state_in)
+    {
+        state_in->step = step_a;
+        state_in->plainchar = 0;
+    }
+
+    int base64_decode_block(const char* code_in, const int length_in, char* plaintext_out, base64_decodestate* state_in)
+    {
+        const char* codechar = code_in;
+        char* plainchar = plaintext_out;
+        char fragment;
+
+        *plainchar = state_in->plainchar;
+
+        switch (state_in->step)
+        {
+            while (1)
+            {
+        case step_a:
+                do {
+                    if (codechar == code_in+length_in)
+                    {
+                        state_in->step = step_a;
+                        state_in->plainchar = *plainchar;
+                        return plainchar - plaintext_out;
+                    }
+                    fragment = (char)base64_decode_value(*codechar++);
+                } while (fragment < 0);
+                *plainchar    = (fragment & 0x03f) << 2;
+        case step_b:
+                do {
+                    if (codechar == code_in+length_in)
+                    {
+                        state_in->step = step_b;
+                        state_in->plainchar = *plainchar;
+                        return plainchar - plaintext_out;
+                    }
+                    fragment = (char)base64_decode_value(*codechar++);
+                } while (fragment < 0);
+                *plainchar++ |= (fragment & 0x030) >> 4;
+                *plainchar    = (fragment & 0x00f) << 4;
+        case step_c:
+                do {
+                    if (codechar == code_in+length_in)
+                    {
+                        state_in->step = step_c;
+                        state_in->plainchar = *plainchar;
+                        return plainchar - plaintext_out;
+                    }
+                    fragment = (char)base64_decode_value(*codechar++);
+                } while (fragment < 0);
+                *plainchar++ |= (fragment & 0x03c) >> 2;
+                *plainchar    = (fragment & 0x003) << 6;
+        case step_d:
+                do {
+                    if (codechar == code_in+length_in)
+                    {
+                        state_in->step = step_d;
+                        state_in->plainchar = *plainchar;
+                        return plainchar - plaintext_out;
+                    }
+                    fragment = (char)base64_decode_value(*codechar++);
+                } while (fragment < 0);
+                *plainchar++   |= (fragment & 0x03f);
+            }
+        }
+        /* control should not reach here */
+        return plainchar - plaintext_out;
+    }
+
+    void base64_init_encodestate(base64_encodestate* state_in)
+    {
+        state_in->step = step_A;
+        state_in->result = 0;
+        state_in->stepcount = 0;
+    }
+
+    char base64_encode_value(char value_in)
+    {
+        static const char* encoding = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+        if (value_in > 63) return '=';
+        return encoding[(int)value_in];
+    }
+
+    int base64_encode_block(const char* plaintext_in, int length_in, char* code_out, base64_encodestate* state_in)
+    {
+        const char* plainchar = plaintext_in;
+        const char* const plaintextend = plaintext_in + length_in;
+        char* codechar = code_out;
+        char result;
+        char fragment;
+
+        result = state_in->result;
+
+        switch (state_in->step)
+        {
+            while (1)
+            {
+        case step_A:
+                if (plainchar == plaintextend)
+                {
+                    state_in->result = result;
+                    state_in->step = step_A;
+                    return codechar - code_out;
+                }
+                fragment = *plainchar++;
+                result = (fragment & 0x0fc) >> 2;
+                *codechar++ = base64_encode_value(result);
+                result = (fragment & 0x003) << 4;
+        case step_B:
+                if (plainchar == plaintextend)
+                {
+                    state_in->result = result;
+                    state_in->step = step_B;
+                    return codechar - code_out;
+                }
+                fragment = *plainchar++;
+                result |= (fragment & 0x0f0) >> 4;
+                *codechar++ = base64_encode_value(result);
+                result = (fragment & 0x00f) << 2;
+        case step_C:
+                if (plainchar == plaintextend)
+                {
+                    state_in->result = result;
+                    state_in->step = step_C;
+                    return codechar - code_out;
+                }
+                fragment = *plainchar++;
+                result |= (fragment & 0x0c0) >> 6;
+                *codechar++ = base64_encode_value(result);
+                result  = (fragment & 0x03f) >> 0;
+                *codechar++ = base64_encode_value(result);
+
+                ++(state_in->stepcount);
+                if (state_in->stepcount == CHARS_PER_LINE/4)
+                {
+                    *codechar++ = '\n';
+                    state_in->stepcount = 0;
+                }
+            }
+        }
+        /* control should not reach here */
+        return codechar - code_out;
+    }
+
+    int base64_encode_blockend(char* code_out, base64_encodestate* state_in)
+    {
+        char* codechar = code_out;
+
+        switch (state_in->step)
+        {
+        case step_B:
+            *codechar++ = base64_encode_value(state_in->result);
+            *codechar++ = '=';
+            *codechar++ = '=';
+            break;
+        case step_C:
+            *codechar++ = base64_encode_value(state_in->result);
+            *codechar++ = '=';
+            break;
+        case step_A:
+            break;
+        }
+        *codechar++ = '\n';
+
+        return codechar - code_out;
+    }
+
+    int Base64encoder::encode(char value_in)
+    {
+        return base64_encode_value(value_in);
+    }
+
+    int Base64encoder::encode(const char* code_in, const int length_in, char* plaintext_out)
+    {
+        return base64_encode_block(code_in, length_in, plaintext_out, &_state);
+    }
+
+    int Base64encoder::encode_end(char* plaintext_out)
+    {
+        return base64_encode_blockend(plaintext_out, &_state);
+    }
+
+    void Base64encoder::encode(std::istream& istream_in, std::ostream& ostream_in)
+    {
+        base64_init_encodestate(&_state);
+
+        const int N = _buffersize;
+        char* plaintext = new char[N];
+        char* code = new char[2*N];
+        int plainlength;
+        int codelength;
+
+        do
+        {
+            istream_in.read(plaintext, N);
+            plainlength = istream_in.gcount();
+
+            codelength = encode(plaintext, plainlength, code);
+            ostream_in.write(code, codelength);
+        }
+        while (istream_in.good() && plainlength > 0);
+
+        codelength = encode_end(code);
+        ostream_in.write(code, codelength);
+
+        base64_init_encodestate(&_state);
+
+        delete [] code;
+        delete [] plaintext;
+    }
+
+    void Base64encoder::encode(const char* chars_in, int length_in, std::string& code_out)
+    {
+        std::stringstream stream_out;
+        {
+            std::stringstream stream_in;
+            {
+                stream_in<<std::string(chars_in, length_in);
+            }
+            stream_in.seekg(0, stream_in.beg);
+            encode(stream_in, stream_out);
+        }
+        stream_out.seekg (0, stream_out.beg);
+        code_out = stream_out.str();
+    }
+
+    int Base64decoder::decode(char value_in)
+    {
+        return base64_decode_value(value_in);
+    }
+
+    int Base64decoder::decode(const char* code_in, const int length_in, char* plaintext_out)
+    {
+        return base64_decode_block(code_in, length_in, plaintext_out, &_state);
+    }
+
+    void Base64decoder::decode(std::istream& istream_in, std::ostream& ostream_in)
+    {
+        base64_init_decodestate(&_state);
+
+        const int N = _buffersize;
+        char* code = new char[N];
+        char* plaintext = new char[N];
+        int codelength;
+        int plainlength;
+
+        do
+        {
+            istream_in.read((char*)code, N);
+            codelength = istream_in.gcount();
+            plainlength = decode(code, codelength, plaintext);
+            ostream_in.write((const char*)plaintext, plainlength);
+        }
+        while (istream_in.good() && codelength > 0);
+
+        base64_init_decodestate(&_state);
+
+        delete [] code;
+        delete [] plaintext;
+    }
+
+    char* Base64decoder::decode(const std::vector<std::string>& str_in, std::vector<unsigned int>& pos_out)
+    {
+        std::stringstream stream_out;
+        {
+            std::stringstream stream_in;
+
+            pos_out.resize(str_in.size());
+
+            for (unsigned int i = 0; i < str_in.size(); ++i)
+            {
+                stream_in.clear();
+                stream_in<<str_in.at(i);
+                stream_in.seekg(0, stream_in.beg);
+
+                decode(stream_in, stream_out);
+                pos_out.at(i) = stream_out.tellp();
+            }
+        }
+
+        // Allocate memory for use with osg::Image
+        char* allocated_out = new char[stream_out.tellp()];
+        memcpy(allocated_out, stream_out.str().c_str(), stream_out.tellp());
+
+        return allocated_out;
+    }
+
+} // namespace osgDB