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chromium / chromium / src / refs/tags/123.0.6312.28 / . / pdf / loader / chunk_stream.h
blob: 00f8e386fb9b866108264ed867a2ce6c3f4492b0 [file] [log] [blame]
Avi Drissmandb497b32022-09-15 19:47:28[diff] [blame]1// Copyright 2010 The Chromium Authors
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
K. Moonefbad4c92022-06-16 20:34:48[diff] [blame]5#ifndef PDF_LOADER_CHUNK_STREAM_H_
6#define PDF_LOADER_CHUNK_STREAM_H_
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]7
8#include <stddef.h>
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]9#include <string.h>
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]10
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]11#include <algorithm>
12#include <array>
13#include <memory>
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]14#include <utility>
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]15#include <vector>
16
K. Moonefbad4c92022-06-16 20:34:48[diff] [blame]17#include "pdf/loader/range_set.h"
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]18
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]19namespace chrome_pdf {
20
21// This class collects a chunks of data into one data stream. Client can check
22// if data in certain range is available, and get missing chunks of data.
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]23template <size_t N>
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]24class ChunkStream {
25 public:
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]26 static constexpr size_t kChunkSize = N;
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]27 using ChunkData = typename std::array<unsigned char, N>;
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]28
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]29 ChunkStream() {}
30 ~ChunkStream() {}
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]31
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]32 void SetChunkData(size_t chunk_index, std::unique_ptr<ChunkData> data) {
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]33 if (!data)
34 return;
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]35
36 if (chunk_index >= data_.size())
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]37 data_.resize(chunk_index + 1);
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]38
39 if (!data_[chunk_index])
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]40 ++filled_chunks_count_;
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]41
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]42 data_[chunk_index] = std::move(data);
43 filled_chunks_.Union(gfx::Range(chunk_index, chunk_index + 1));
44 }
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]45
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]46 bool ReadData(const gfx::Range& range, void* buffer) const {
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]47 if (!IsRangeAvailable(range))
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]48 return false;
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]49
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]50 unsigned char* data_buffer = static_cast<unsigned char*>(buffer);
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]51 size_t start = range.start();
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]52 while (start != range.end()) {
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]53 const size_t chunk_index = GetChunkIndex(start);
54 const size_t chunk_start = start % kChunkSize;
55 const size_t len =
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]56 std::min(kChunkSize - chunk_start, range.end() - start);
57 memcpy(data_buffer, data_[chunk_index]->data() + chunk_start, len);
58 data_buffer += len;
59 start += len;
60 }
61 return true;
62 }
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]63
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]64 size_t GetChunkIndex(size_t offset) const { return offset / kChunkSize; }
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]65
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]66 gfx::Range GetChunksRange(size_t offset, size_t size) const {
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]67 return gfx::Range(GetChunkIndex(offset), GetChunkEnd(offset + size));
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]68 }
69
70 bool IsRangeAvailable(const gfx::Range& range) const {
71 if (!range.IsValid() || range.is_reversed() ||
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]72 (eof_pos_ > 0 && eof_pos_ < range.end())) {
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]73 return false;
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]74 }
75
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]76 if (range.is_empty())
77 return true;
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]78
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]79 const gfx::Range chunks_range(GetChunkIndex(range.start()),
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]80 GetChunkEnd(range.end()));
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]81 return filled_chunks_.Contains(chunks_range);
82 }
83
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]84 bool IsChunkAvailable(size_t chunk_index) const {
Artem Strygin2cf20af42018-06-14 14:26:53[diff] [blame]85 return filled_chunks_.Contains(chunk_index);
86 }
87
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]88 void set_eof_pos(size_t eof_pos) { eof_pos_ = eof_pos; }
89 size_t eof_pos() const { return eof_pos_; }
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]90
91 const RangeSet& filled_chunks() const { return filled_chunks_; }
92
93 bool IsComplete() const {
94 return eof_pos_ > 0 && IsRangeAvailable(gfx::Range(0, eof_pos_));
95 }
96
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]97 bool IsValidChunkIndex(size_t chunk_index) const {
Artem Strygin2cf20af42018-06-14 14:26:53[diff] [blame]98 return !eof_pos_ || (chunk_index <= GetChunkIndex(eof_pos_ - 1));
99 }
100
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]101 void Clear() {
102 data_.clear();
103 eof_pos_ = 0;
104 filled_chunks_.Clear();
105 filled_chunks_count_ = 0;
106 }
107
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]108 size_t filled_chunks_count() const { return filled_chunks_count_; }
109 size_t total_chunks_count() const { return GetChunkEnd(eof_pos_); }
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]110
111 private:
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]112 size_t GetChunkEnd(size_t offset) const {
Lei Zhangfc4640d62018-03-28 17:30:36[diff] [blame]113 return (offset + kChunkSize - 1) / kChunkSize;
114 }
115
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]116 std::vector<std::unique_ptr<ChunkData>> data_;
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]117 size_t eof_pos_ = 0;
Artem Stryginaf1b43422017-09-12 18:48:24[diff] [blame]118 RangeSet filled_chunks_;
Peter Kasting43fddaaa2022-06-28 02:44:28[diff] [blame]119 size_t filled_chunks_count_ = 0;
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]120};
121
Nico Weber40cd26fd2019-02-09 17:37:02[diff] [blame]122} // namespace chrome_pdf
jam@chromium.org1b1e9eff2014-05-20 01:56:40[diff] [blame]123
K. Moonefbad4c92022-06-16 20:34:48[diff] [blame]124#endif // PDF_LOADER_CHUNK_STREAM_H_