blob: 2ab347ae8ee359492a6407985afac5f19b6167c3 [file] [log] [blame]
// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_EXTENT_RANGES_H__
#define CHROMEOS_PLATFORM_UPDATE_ENGINE_EXTENT_RANGES_H__
#include <map>
#include <set>
#include <vector>
#include <base/basictypes.h>
#include "update_engine/delta_diff_generator.h"
#include "update_engine/graph_types.h"
#include "update_engine/update_metadata.pb.h"
// An ExtentRanges object represents an unordered collection of extents (and
// therefore blocks). Such an object may be modified by adding or subtracting
// blocks (think: set addition or set subtraction). Note that ExtentRanges
// ignores sparse hole extents mostly to avoid confusion between extending a
// sparse hole range vs. set addition but also to ensure that the delta
// generator doesn't use sparse holes as scratch space.
namespace chromeos_update_engine {
struct ExtentLess {
bool operator()(const Extent& x, const Extent& y) const {
return x.start_block() < y.start_block();
}
};
Extent ExtentForRange(uint64_t start_block, uint64_t num_blocks);
class ExtentRanges {
public:
typedef std::set<Extent, ExtentLess> ExtentSet;
ExtentRanges() : blocks_(0) {}
void AddBlock(uint64_t block);
void SubtractBlock(uint64_t block);
void AddExtent(Extent extent);
void SubtractExtent(const Extent& extent);
void AddExtents(const std::vector<Extent>& extents);
void SubtractExtents(const std::vector<Extent>& extents);
void AddRepeatedExtents(
const ::google::protobuf::RepeatedPtrField<Extent> &exts);
void SubtractRepeatedExtents(
const ::google::protobuf::RepeatedPtrField<Extent> &exts);
void AddRanges(const ExtentRanges& ranges);
void SubtractRanges(const ExtentRanges& ranges);
static bool ExtentsOverlapOrTouch(const Extent& a, const Extent& b);
static bool ExtentsOverlap(const Extent& a, const Extent& b);
// Dumps contents to the log file. Useful for debugging.
void Dump() const;
uint64_t blocks() const { return blocks_; }
const ExtentSet& extent_set() const { return extent_set_; }
// Returns an ordered vector of extents for |count| blocks,
// using extents in extent_set_. The returned extents are not
// removed from extent_set_. |count| must be less than or equal to
// the number of blocks in this extent set.
std::vector<Extent> GetExtentsForBlockCount(uint64_t count) const;
private:
ExtentSet extent_set_;
uint64_t blocks_;
};
} // namespace chromeos_update_engine
#endif // CHROMEOS_PLATFORM_UPDATE_ENGINE_EXTENT_RANGES_H__