thin-provisioning-tools/contrib/tmakatos_emitter.cc

#include "thin-provisioning/emitter.h"
#include "contrib/tmakatos_emitter.h"

#include <iostream>
#include <climits>

using namespace std;
using namespace thin_provisioning;

//----------------------------------------------------------------

namespace tmakatos_emitter {
	template <typename T>
	std::ostream &operator << (ostream &out, boost::optional<T> const &maybe) {
		if (maybe)
			out << *maybe;

		return out;
	}

	//------------------------------------------------
	// binary generator
	//------------------------------------------------
	binary_emitter::binary_emitter(ostream &out): out_(out) {
	}

	void binary_emitter::begin_superblock(string const &uuid,
			      uint64_t time,
			      uint64_t trans_id,
			      boost::optional<uint32_t> flags,
			      boost::optional<uint32_t> version,
			      uint32_t data_block_size,
			      uint64_t nr_data_blocks,
			      boost::optional<uint64_t> metadata_snap) {
	}

	void binary_emitter::end_superblock() {
	}

	void binary_emitter::begin_device(uint32_t dev_id,
			  uint64_t mapped_blocks,
			  uint64_t trans_id,
			  uint64_t creation_time,
			  uint64_t snap_time) {
		cur = 0;
		bitmap = 0;
	}

	void binary_emitter::end_device() {
		emit_bmp(true);
	}

	void binary_emitter::begin_named_mapping(string const &name) { }

	void binary_emitter::end_named_mapping() { }

	void binary_emitter::identifier(string const &name) { }

	void binary_emitter::range_map(uint64_t origin_begin, uint64_t, uint32_t,
		       uint64_t len) {

		uint64_t n = origin_begin / unit;
		uint64_t i;

		assert(n >= cur);
		assert(len > 0);

		/*
		 * Cover the gap between the last emitted unit and the current one.
		 */
		if (n > cur)
			do { emit_bmp(); } while (cur < n);

		/*
		 * Emit partial unit.
		 */
		if (origin_begin & (unit - 1)) {
			const uint64_t j = min(len,
					       (origin_begin & ~(unit - 1)) + unit - origin_begin);
			for (i = origin_begin; i < origin_begin + j; i++)
				bitmap |= 1ULL << (i & (unit - 1));
			if (j == len)
				return;

			emit_bmp();

			len -= j;
			origin_begin = i;
		}

		/*
		 * Emit full units until end.
		 */
		n = (origin_begin + len) / unit;
		while (cur < n) {
			bitmap = ~0;
			emit_bmp();
			len -= unit;
		}
		origin_begin = cur * unit;

		/*
		 * Emit final unit.
		 */
		for (i = origin_begin; i < origin_begin + len; i++)
			bitmap |= 1ULL << (i & (unit - 1));
	}

	void binary_emitter::single_map(uint64_t origin_block, uint64_t, uint32_t) {
		range_map(origin_block, 0, 0, 1);
	}

	void binary_emitter::emit_bmp(bool omit_if_zero) {
		if (bitmap || !omit_if_zero)
			out_.write((const char*)&bitmap, sizeof bitmap);
		bitmap = 0;
		cur++;
	}
}

//----------------------------------------------------------------

extern "C" {
	emitter::ptr create_emitter(ostream &out) {
		return emitter::ptr(new tmakatos_emitter::binary_emitter(out));
	}
}

//----------------------------------------------------------------