transmission/tests/libtransmission/file-piece-map-test.cc

375 lines
14 KiB
C++

// This file Copyright (C) 2021-2022 Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#include <array>
#include <numeric>
#include <cstdint>
#include "transmission.h"
#include "block-info.h"
#include "file-piece-map.h"
#include "gtest/gtest.h"
class FilePieceMapTest : public ::testing::Test
{
protected:
static constexpr size_t PieceSize{ tr_block_info::BlockSize };
static constexpr size_t TotalSize{ 10 * PieceSize + 1 };
tr_block_info const block_info_{ TotalSize, PieceSize };
static constexpr std::array<uint64_t, 17> FileSizes{
5 * PieceSize, // [offset 0] begins and ends on a piece boundary
0, // [offset 5 P] zero-sized files
0,
0,
0,
PieceSize / 2, // [offset 5 P] begins on a piece boundary
PieceSize, // [offset 5.5 P] neither begins nor ends on a piece boundary, spans >1 piece
10, // [offset 6.5 P] small files all contained in a single piece
9,
8,
7,
6,
(3 * PieceSize + PieceSize / 2 + 1 - 10 - 9 - 8 - 7 - 6), // [offset 5.75P +10+9+8+7+6] ends end-of-torrent
0, // [offset 10P+1] zero-sized files at the end-of-torrent
0,
0,
0,
// sum is 10P + 1 == TotalSize
};
void SetUp() override
{
static_assert(
FileSizes[0] + FileSizes[1] + FileSizes[2] + FileSizes[3] + FileSizes[4] + FileSizes[5] + FileSizes[6] +
FileSizes[7] + FileSizes[8] + FileSizes[9] + FileSizes[10] + FileSizes[11] + FileSizes[12] + FileSizes[13] +
FileSizes[14] + FileSizes[15] + FileSizes[16] ==
TotalSize);
EXPECT_EQ(11U, block_info_.pieceCount());
EXPECT_EQ(PieceSize, block_info_.pieceSize());
EXPECT_EQ(TotalSize, block_info_.totalSize());
EXPECT_EQ(TotalSize, std::accumulate(std::begin(FileSizes), std::end(FileSizes), uint64_t{ 0 }));
}
};
TEST_F(FilePieceMapTest, fileOffset)
{
auto const fpm = tr_file_piece_map{ block_info_, std::data(FileSizes), std::size(FileSizes) };
// first byte of the first file
auto file_offset = fpm.fileOffset(0);
EXPECT_EQ(0U, file_offset.index);
EXPECT_EQ(0U, file_offset.offset);
// final byte of the first file
file_offset = fpm.fileOffset(FileSizes[0] - 1);
EXPECT_EQ(0U, file_offset.index);
EXPECT_EQ(FileSizes[0] - 1, file_offset.offset);
// first byte of the second file
// NB: this is an edge case, second file is 0 bytes.
// The second nonzero file is file #5
file_offset = fpm.fileOffset(FileSizes[0]);
EXPECT_EQ(5U, file_offset.index);
EXPECT_EQ(0U, file_offset.offset);
// the last byte of in the torrent.
// NB: reverse of previous edge case, since
// the final 4 files in the torrent are all 0 bytes
file_offset = fpm.fileOffset(TotalSize - 1);
EXPECT_EQ(12U, file_offset.index);
EXPECT_EQ(FileSizes[12] - 1, file_offset.offset);
}
TEST_F(FilePieceMapTest, pieceSpan)
{
// Note to reviewers: it's easy to see a nonexistent fencepost error here.
// Remember everything is zero-indexed, so the 11 valid pieces are [0..10]
// and that last piece #10 has one byte in it. Piece #11 is the 'end' iterator position.
auto constexpr ExpectedPieceSpans = std::array<tr_file_piece_map::piece_span_t, 17>{ {
{ 0, 5 },
{ 5, 6 },
{ 5, 6 },
{ 5, 6 },
{ 5, 6 },
{ 5, 6 },
{ 5, 7 },
{ 6, 7 },
{ 6, 7 },
{ 6, 7 },
{ 6, 7 },
{ 6, 7 },
{ 6, 11 },
{ 10, 11 },
{ 10, 11 },
{ 10, 11 },
{ 10, 11 },
} };
EXPECT_EQ(std::size(FileSizes), std::size(ExpectedPieceSpans));
auto const fpm = tr_file_piece_map{ block_info_, std::data(FileSizes), std::size(FileSizes) };
tr_file_index_t const n = std::size(fpm);
EXPECT_EQ(std::size(FileSizes), n);
uint64_t offset = 0;
for (tr_file_index_t file = 0; file < n; ++file)
{
EXPECT_EQ(ExpectedPieceSpans[file].begin, fpm.pieceSpan(file).begin);
EXPECT_EQ(ExpectedPieceSpans[file].end, fpm.pieceSpan(file).end);
offset += FileSizes[file];
}
EXPECT_EQ(TotalSize, offset);
EXPECT_EQ(block_info_.pieceCount(), fpm.pieceSpan(std::size(FileSizes) - 1).end);
}
TEST_F(FilePieceMapTest, priorities)
{
auto const fpm = tr_file_piece_map{ block_info_, std::data(FileSizes), std::size(FileSizes) };
auto file_priorities = tr_file_priorities(&fpm);
tr_file_index_t const n_files = std::size(FileSizes);
// make a helper to compare file & piece priorities
auto expected_file_priorities = std::vector<tr_priority_t>(n_files, TR_PRI_NORMAL);
auto expected_piece_priorities = std::vector<tr_priority_t>(block_info_.pieceCount(), TR_PRI_NORMAL);
auto const compare_to_expected = [&, this]()
{
for (tr_file_index_t i = 0; i < n_files; ++i)
{
EXPECT_EQ(int(expected_file_priorities[i]), int(file_priorities.filePriority(i)));
}
for (tr_piece_index_t i = 0; i < block_info_.pieceCount(); ++i)
{
EXPECT_EQ(int(expected_piece_priorities[i]), int(file_priorities.piecePriority(i)));
}
};
// check default priority is normal
compare_to_expected();
// set the first file as high priority.
// since this begins and ends on a piece boundary,
// this shouldn't affect any other files' pieces
auto pri = TR_PRI_HIGH;
file_priorities.set(0, pri);
expected_file_priorities[0] = pri;
for (size_t i = 0; i < 5; ++i)
{
expected_piece_priorities[i] = pri;
}
compare_to_expected();
// This file shares a piece with another file.
// If _either_ is set to high, the piece's priority should be high.
// file #5: byte [500..550) piece [5, 6)
// file #6: byte [550..650) piece [5, 7)
//
// first test setting file #5...
pri = TR_PRI_HIGH;
file_priorities.set(5, pri);
expected_file_priorities[5] = pri;
expected_piece_priorities[5] = pri;
compare_to_expected();
// ...and that shared piece should still be the same when both are high...
file_priorities.set(6, pri);
expected_file_priorities[6] = pri;
expected_piece_priorities[5] = pri;
expected_piece_priorities[6] = pri;
compare_to_expected();
// ...and that shared piece should still be the same when only 6 is high...
pri = TR_PRI_NORMAL;
file_priorities.set(5, pri);
expected_file_priorities[5] = pri;
compare_to_expected();
// setup for the next test: set all files to low priority
pri = TR_PRI_LOW;
for (tr_file_index_t i = 0; i < n_files; ++i)
{
file_priorities.set(i, pri);
}
std::fill(std::begin(expected_file_priorities), std::end(expected_file_priorities), pri);
std::fill(std::begin(expected_piece_priorities), std::end(expected_piece_priorities), pri);
compare_to_expected();
// Raise the priority of a small 1-piece file.
// Since it's the highest priority in the piece, piecePriority() should return its value.
// file #8: byte [650, 659) piece [6, 7)
pri = TR_PRI_NORMAL;
file_priorities.set(8, pri);
expected_file_priorities[8] = pri;
expected_piece_priorities[6] = pri;
compare_to_expected();
// Raise the priority of another small 1-piece file in the same piece.
// Since _it_ now has the highest priority in the piece, piecePriority should return _its_ value.
// file #9: byte [659, 667) piece [6, 7)
pri = TR_PRI_HIGH;
file_priorities.set(9, pri);
expected_file_priorities[9] = pri;
expected_piece_priorities[6] = pri;
compare_to_expected();
// Prep for the next test: set all files to normal priority
pri = TR_PRI_NORMAL;
for (tr_file_index_t i = 0; i < n_files; ++i)
{
file_priorities.set(i, pri);
}
std::fill(std::begin(expected_file_priorities), std::end(expected_file_priorities), pri);
std::fill(std::begin(expected_piece_priorities), std::end(expected_piece_priorities), pri);
compare_to_expected();
// *Sigh* OK what happens to piece priorities if you set the priority
// of a zero-byte file. Arguably nothing should happen since you can't
// download an empty file. But that would complicate the code for a
// pretty stupid use case, and treating 0-sized files the same as any
// other does no real harm. Let's KISS.
//
// Check that even zero-sized files can change a piece's priority
// file #1: byte [500, 500) piece [5, 6)
pri = TR_PRI_HIGH;
file_priorities.set(1, pri);
expected_file_priorities[1] = pri;
expected_piece_priorities[5] = pri;
compare_to_expected();
// Check that zero-sized files at the end of a torrent change the last piece's priority.
// file #16 byte [1001, 1001) piece [10, 11)
file_priorities.set(16, pri);
expected_file_priorities[16] = pri;
expected_piece_priorities[10] = pri;
compare_to_expected();
// test the batch API
auto file_indices = std::vector<tr_file_index_t>(n_files);
std::iota(std::begin(file_indices), std::end(file_indices), 0);
pri = TR_PRI_HIGH;
file_priorities.set(std::data(file_indices), std::size(file_indices), pri);
std::fill(std::begin(expected_file_priorities), std::end(expected_file_priorities), pri);
std::fill(std::begin(expected_piece_priorities), std::end(expected_piece_priorities), pri);
compare_to_expected();
pri = TR_PRI_LOW;
file_priorities.set(std::data(file_indices), std::size(file_indices), pri);
std::fill(std::begin(expected_file_priorities), std::end(expected_file_priorities), pri);
std::fill(std::begin(expected_piece_priorities), std::end(expected_piece_priorities), pri);
compare_to_expected();
}
TEST_F(FilePieceMapTest, wanted)
{
auto const fpm = tr_file_piece_map{ block_info_, std::data(FileSizes), std::size(FileSizes) };
auto files_wanted = tr_files_wanted(&fpm);
tr_file_index_t const n_files = std::size(FileSizes);
// make a helper to compare file & piece priorities
auto expected_files_wanted = tr_bitfield(n_files);
auto expected_pieces_wanted = tr_bitfield(block_info_.pieceCount());
auto const compare_to_expected = [&, this]()
{
for (tr_file_index_t i = 0; i < n_files; ++i)
{
EXPECT_EQ(int(expected_files_wanted.test(i)), int(files_wanted.fileWanted(i)));
}
for (tr_piece_index_t i = 0; i < block_info_.pieceCount(); ++i)
{
EXPECT_EQ(int(expected_pieces_wanted.test(i)), int(files_wanted.pieceWanted(i)));
}
};
// check everything is wanted by default
expected_files_wanted.setHasAll();
expected_pieces_wanted.setHasAll();
compare_to_expected();
// set the first file as not wanted.
// since this begins and ends on a piece boundary,
// this shouldn't affect any other files' pieces
bool const wanted = false;
files_wanted.set(0, wanted);
expected_files_wanted.set(0, wanted);
expected_pieces_wanted.setSpan(0, 5, wanted);
compare_to_expected();
// now test when a piece has >1 file.
// if *any* file in that piece is wanted, then we want the piece too.
// file #1: byte [100..100) piece [5, 6) (zero-byte file)
// file #2: byte [100..100) piece [5, 6) (zero-byte file)
// file #3: byte [100..100) piece [5, 6) (zero-byte file)
// file #4: byte [100..100) piece [5, 6) (zero-byte file)
// file #5: byte [500..550) piece [5, 6)
// file #6: byte [550..650) piece [5, 7)
//
// first test setting file #5...
files_wanted.set(5, false);
expected_files_wanted.unset(5);
compare_to_expected();
// marking all the files in the piece as unwanted
// should cause the piece to become unwanted
files_wanted.set(1, false);
files_wanted.set(2, false);
files_wanted.set(3, false);
files_wanted.set(4, false);
files_wanted.set(5, false);
files_wanted.set(6, false);
expected_files_wanted.setSpan(1, 7, false);
expected_pieces_wanted.unset(5);
compare_to_expected();
// but as soon as any of them is turned back to wanted,
// the piece should pop back.
files_wanted.set(6, true);
expected_files_wanted.set(6, true);
expected_pieces_wanted.set(5);
compare_to_expected();
files_wanted.set(5, true);
files_wanted.set(6, false);
expected_files_wanted.set(5);
expected_files_wanted.unset(6);
compare_to_expected();
files_wanted.set(4, true);
files_wanted.set(5, false);
expected_files_wanted.set(4);
expected_files_wanted.unset(5);
compare_to_expected();
// Prep for the next test: set all files to unwanted priority
for (tr_file_index_t i = 0; i < n_files; ++i)
{
files_wanted.set(i, false);
}
expected_files_wanted.setHasNone();
expected_pieces_wanted.setHasNone();
compare_to_expected();
// *Sigh* OK what happens to files_wanted if you say the only
// file you want is a zero-byte file? Arguably nothing should happen
// since you can't download a zero-byte file. But that would complicate
// the coe for a stupid use case, so let's KISS.
//
// Check that even zero-sized files can change a file's 'wanted' state
// file #1: byte [500, 500) piece [5, 6)
files_wanted.set(1, true);
expected_files_wanted.set(1);
expected_pieces_wanted.set(5);
compare_to_expected();
// Check that zero-sized files at the end of a torrent change the last piece's state.
// file #16 byte [1001, 1001) piece [10, 11)
files_wanted.set(16, true);
expected_files_wanted.set(16);
expected_pieces_wanted.set(10);
compare_to_expected();
// test the batch API
auto file_indices = std::vector<tr_file_index_t>(n_files);
std::iota(std::begin(file_indices), std::end(file_indices), 0);
files_wanted.set(std::data(file_indices), std::size(file_indices), true);
expected_files_wanted.setHasAll();
expected_pieces_wanted.setHasAll();
compare_to_expected();
files_wanted.set(std::data(file_indices), std::size(file_indices), false);
expected_files_wanted.setHasNone();
expected_pieces_wanted.setHasNone();
compare_to_expected();
}