add preliminary xdr input driver

#ifndef XDRINPUT_H

#define XDRINPUT_H

#include <stdint.h>

class XDRInput {

	private:

		XDRInput(const XDRInput& copy);

		char *data;

		uint32_t pos;

	public:

		XDRInput(char *d) : pos(0) { data = d; }

		uint32_t get_uint32();

		int32_t get_int32();

		uint64_t get_uint64();

		int64_t get_int64();

		uint32_t get_opaque_length();

		char* get_opaque(uint32_t length);

};

#endif

#include "object/xdrinput.h"

uint32_t XDRInput::get_uint32()

{

	uint32_t ret = ((uint8_t)data[pos]<<24) | ((uint8_t)data[pos+1]<<16)

		| ((uint8_t)data[pos+2]<<8) | (uint8_t)data[pos+3];

	pos += 4;

	return ret;

}

int32_t XDRInput::get_int32()

{

	int32_t ret = (data[pos]<<24) | (data[pos+1]<<16) | (data[pos+2]<<8) | data[pos+3];

	pos += 4;

	return ret;

}

uint64_t XDRInput::get_uint64()

{

	uint64_t ret0 = ((uint8_t)data[pos]<<24) | ((uint8_t)data[pos+1]<<16)

		| ((uint8_t)data[pos+2]<<8) | (uint8_t)data[pos+3];

	pos += 4;

	uint64_t ret1 = ((uint8_t)data[pos]<<24) | ((uint8_t)data[pos+1]<<16)

		| ((uint8_t)data[pos+2]<<8) | (uint8_t)data[pos+3];

	pos += 4;

	return (ret0 << 32) | ret1;

}

int64_t XDRInput::get_int64()

{

	int64_t ret0 = (data[pos]<<24) | (data[pos+1]<<16) | (data[pos+2]<<8) | data[pos+3];

	pos += 4;

	int64_t ret1 = (data[pos]<<24) | (data[pos+1]<<16) | (data[pos+2]<<8) | data[pos+3];

	pos += 4;

	return (ret0 << 32) | ret1;

}

uint32_t XDRInput::get_opaque_length()

{

	return get_uint32();

}

char *XDRInput::get_opaque(uint32_t length)

{

	char *ret = data + pos;

	pos += length;

	if (length % 4) {

		pos += 4 - (length % 4);

	}

	return ret;

}