Code so far

data.cpp

@@ -0,0 +1,70 @@
+#include "data.h"
+#include <cstring>
+
+/* PycData */
+int PycData::get16()
+{
+    /* Ensure endianness */
+    int val = ( ((getByte() & 0xFF)     )
+              | ((getByte() & 0xFF) << 8)
+              );
+
+    /* Extend sign */
+    return (val | -(val & 0x8000));
+}
+
+int PycData::get32()
+{
+    /* Ensure endianness */
+    return (int)( ((getByte() & 0xFF)      )
+                | ((getByte() & 0xFF) <<  8)
+                | ((getByte() & 0xFF) << 16)
+                | ((getByte() & 0xFF) << 24)
+                );
+}
+
+
+/* PycFile */
+PycFile::PycFile(const char* filename)
+{
+    m_stream = fopen(filename, "rb");
+}
+
+bool PycFile::atEof() const
+{
+    int ch = fgetc(m_stream);
+    ungetc(ch, m_stream);
+    return (ch == EOF);
+}
+
+int PycFile::getByte()
+{
+    int ch = fgetc(m_stream);
+    if (ch == EOF)
+        ungetc(ch, m_stream);
+    return ch;
+}
+
+int PycFile::getBuffer(int bytes, void* buffer)
+{
+    return (int)fread(buffer, 1, bytes, m_stream);
+}
+
+
+/* PycBuffer */
+int PycBuffer::getByte()
+{
+    if (atEof())
+        return EOF;
+    int ch = (int)(*(m_buffer + m_pos));
+    ++m_pos;
+    return ch & 0xFF;   // Make sure it's just a byte!
+}
+
+int PycBuffer::getBuffer(int bytes, void* buffer)
+{
+    if (m_pos + bytes > m_size)
+        bytes = m_size - m_pos;
+    memcpy(buffer, (m_buffer + m_pos), bytes);
+    return bytes;
+}