Initial community commit

Src/external_dependencies/openmpt-trunk/include/unrar/getbits.hpp

@@ -0,0 +1,68 @@
+#ifndef _RAR_GETBITS_
+#define _RAR_GETBITS_
+
+class BitInput
+{
+  public:
+    enum BufferSize {MAX_SIZE=0x8000}; // Size of input buffer.
+
+    int InAddr; // Curent byte position in the buffer.
+    int InBit;  // Current bit position in the current byte.
+
+    bool ExternalBuffer;
+  public:
+    BitInput(bool AllocBuffer);
+    ~BitInput();
+
+    byte *InBuf; // Dynamically allocated input buffer.
+
+    void InitBitInput()
+    {
+      InAddr=InBit=0;
+    }
+    
+    // Move forward by 'Bits' bits.
+    void addbits(uint Bits)
+    {
+      Bits+=InBit;
+      InAddr+=Bits>>3;
+      InBit=Bits&7;
+    }
+    
+    // Return 16 bits from current position in the buffer.
+    // Bit at (InAddr,InBit) has the highest position in returning data.
+    uint getbits()
+    {
+      uint BitField=(uint)InBuf[InAddr] << 16;
+      BitField|=(uint)InBuf[InAddr+1] << 8;
+      BitField|=(uint)InBuf[InAddr+2];
+      BitField >>= (8-InBit);
+      return BitField & 0xffff;
+    }
+
+    // Return 32 bits from current position in the buffer.
+    // Bit at (InAddr,InBit) has the highest position in returning data.
+    uint getbits32()
+    {
+      uint BitField=(uint)InBuf[InAddr] << 24;
+      BitField|=(uint)InBuf[InAddr+1] << 16;
+      BitField|=(uint)InBuf[InAddr+2] << 8;
+      BitField|=(uint)InBuf[InAddr+3];
+      BitField <<= InBit;
+      BitField|=(uint)InBuf[InAddr+4] >> (8-InBit);
+      return BitField & 0xffffffff;
+    }
+    
+    void faddbits(uint Bits);
+    uint fgetbits();
+    
+    // Check if buffer has enough space for IncPtr bytes. Returns 'true'
+    // if buffer will be overflown.
+    bool Overflow(uint IncPtr) 
+    {
+      return InAddr+IncPtr>=MAX_SIZE;
+    }
+
+    void SetExternalBuffer(byte *Buf);
+};
+#endif