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

413 lines
16 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 <algorithm>
#include <array>
#include <cstddef> // size_t
#include <cstdint> // uint64_t
#include <numeric>
#include <vector>
#include <libtransmission/transmission.h>
#include <libtransmission/bitfield.h>
#include <libtransmission/block-info.h>
#include <libtransmission/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{
5U * PieceSize, // [offset 0] begins and ends on a piece boundary
0U, // [offset 5 P] zero-sized files
0U,
0U,
0U,
PieceSize / 2U, // [offset 5 P] begins on a piece boundary
PieceSize, // [offset 5.5 P] neither begins nor ends on a piece boundary, spans >1 piece
10U, // [offset 6.5 P] small files all contained in a single piece
9U,
8U,
7U,
6U,
(3U * PieceSize + PieceSize / 2U + 1U - 10U - 9U - 8U - 7U - 6U), // [offset 5.75P +10+9+8+7+6] ends end-of-torrent
0U, // [offset 10P+1] zero-sized files at the end-of-torrent
0U,
0U,
0U,
// 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_.piece_count());
EXPECT_EQ(PieceSize, block_info_.piece_size());
EXPECT_EQ(TotalSize, block_info_.total_size());
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.file_offset(0U);
EXPECT_EQ(0U, file_offset.index);
EXPECT_EQ(0U, file_offset.offset);
// final byte of the first file
file_offset = fpm.file_offset(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.file_offset(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.file_offset(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>{ {
{ 0U, 5U },
{ 5U, 6U },
{ 5U, 6U },
{ 5U, 6U },
{ 5U, 6U },
{ 5U, 6U },
{ 5U, 7U },
{ 6U, 7U },
{ 6U, 7U },
{ 6U, 7U },
{ 6U, 7U },
{ 6U, 7U },
{ 6U, 11U },
{ 10U, 11U },
{ 10U, 11U },
{ 10U, 11U },
{ 10U, 11U },
} };
EXPECT_EQ(std::size(FileSizes), std::size(ExpectedPieceSpans));
auto const fpm = tr_file_piece_map{ block_info_, std::data(FileSizes), std::size(FileSizes) };
auto const n_files = fpm.file_count();
EXPECT_EQ(std::size(FileSizes), n_files);
uint64_t offset = 0U;
for (tr_file_index_t file = 0U; file < n_files; ++file)
{
EXPECT_EQ(ExpectedPieceSpans[file].begin, fpm.piece_span_for_file(file).begin);
EXPECT_EQ(ExpectedPieceSpans[file].end, fpm.piece_span_for_file(file).end);
offset += FileSizes[file];
}
EXPECT_EQ(TotalSize, offset);
EXPECT_EQ(block_info_.piece_count(), fpm.piece_span_for_file(std::size(FileSizes) - 1U).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_.piece_count(), TR_PRI_NORMAL);
auto const compare_to_expected = [&, this]()
{
for (tr_file_index_t i = 0U; i < n_files; ++i)
{
auto const expected = expected_file_priorities[i];
auto const actual = file_priorities.file_priority(i);
EXPECT_EQ(expected, actual) << "idx[" << i << "] expected [" << expected << "] actual [" << actual << ']';
}
for (tr_piece_index_t i = 0U; i < block_info_.piece_count(); ++i)
{
auto const expected = expected_piece_priorities[i];
auto const actual = file_priorities.piece_priority(i);
EXPECT_EQ(expected, actual) << "idx[" << i << "] expected [" << expected << "] actual [" << actual << ']';
}
};
auto const mark_file_endpoints_as_high_priority = [&]()
{
for (tr_file_index_t file = 0U; file < n_files; ++file)
{
auto const [begin_piece, end_piece] = fpm.piece_span_for_file(file);
expected_piece_priorities[begin_piece] = TR_PRI_HIGH;
if (end_piece > begin_piece)
{
expected_piece_priorities[end_piece - 1U] = TR_PRI_HIGH;
}
}
};
// check default priority is normal
mark_file_endpoints_as_high_priority();
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(0U, pri);
expected_file_priorities[0] = pri;
for (size_t i = 0U; i < 5U; ++i)
{
expected_piece_priorities[i] = pri;
}
mark_file_endpoints_as_high_priority();
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(5U, pri);
expected_file_priorities[5] = pri;
expected_piece_priorities[5] = pri;
mark_file_endpoints_as_high_priority();
compare_to_expected();
// ...and that shared piece should still be the same when both are high...
file_priorities.set(6U, pri);
expected_file_priorities[6] = pri;
expected_piece_priorities[5] = pri;
expected_piece_priorities[6] = pri;
mark_file_endpoints_as_high_priority();
compare_to_expected();
// ...and that shared piece should still be the same when only 6 is high...
pri = TR_PRI_NORMAL;
file_priorities.set(5U, pri);
expected_file_priorities[5] = pri;
mark_file_endpoints_as_high_priority();
compare_to_expected();
// setup for the next test: set all files to low priority
pri = TR_PRI_LOW;
for (tr_file_index_t i = 0U; 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);
mark_file_endpoints_as_high_priority();
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(8U, pri);
expected_file_priorities[8] = pri;
expected_piece_priorities[6] = pri;
mark_file_endpoints_as_high_priority();
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(9U, pri);
expected_file_priorities[9] = pri;
expected_piece_priorities[6] = pri;
mark_file_endpoints_as_high_priority();
compare_to_expected();
// Prep for the next test: set all files to normal priority
pri = TR_PRI_NORMAL;
for (tr_file_index_t i = 0U; 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);
mark_file_endpoints_as_high_priority();
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(1U, pri);
expected_file_priorities[1] = pri;
expected_piece_priorities[5] = pri;
mark_file_endpoints_as_high_priority();
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(16U, pri);
expected_file_priorities[16] = pri;
expected_piece_priorities[10] = pri;
mark_file_endpoints_as_high_priority();
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), 0U);
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);
mark_file_endpoints_as_high_priority();
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);
mark_file_endpoints_as_high_priority();
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 wanted bitfields
auto expected_files_wanted = tr_bitfield(n_files);
auto expected_pieces_wanted = tr_bitfield(block_info_.piece_count());
auto const compare_to_expected = [&, this]()
{
for (tr_file_index_t i = 0U; i < n_files; ++i)
{
auto const expected = expected_files_wanted.test(i);
auto const actual = files_wanted.file_wanted(i);
EXPECT_EQ(expected, actual) << "idx[" << i << "] expected [" << expected << "] actual [" << actual << ']';
}
for (tr_piece_index_t i = 0U; i < block_info_.piece_count(); ++i)
{
auto const expected = expected_pieces_wanted.test(i);
auto const actual = files_wanted.piece_wanted(i);
EXPECT_EQ(expected, actual) << "idx[" << i << "] expected [" << expected << "] actual [" << actual << ']';
}
};
// check everything is wanted by default
expected_files_wanted.set_has_all();
expected_pieces_wanted.set_has_all();
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(0U, wanted);
expected_files_wanted.set(0U, wanted);
expected_pieces_wanted.set_span(0U, 5U, 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(5U, false);
expected_files_wanted.unset(5U);
compare_to_expected();
// marking all the files in the piece as unwanted
// should cause the piece to become unwanted
files_wanted.set(1U, false);
files_wanted.set(2U, false);
files_wanted.set(3U, false);
files_wanted.set(4U, false);
files_wanted.set(5U, false);
files_wanted.set(6U, false);
expected_files_wanted.set_span(1U, 7U, false);
expected_pieces_wanted.unset(5U);
compare_to_expected();
// but as soon as any of them is turned back to wanted,
// the piece should pop back.
files_wanted.set(6U, true);
expected_files_wanted.set(6U, true);
expected_pieces_wanted.set(5U);
compare_to_expected();
files_wanted.set(5U, true);
files_wanted.set(6U, false);
expected_files_wanted.set(5U);
expected_files_wanted.unset(6U);
compare_to_expected();
files_wanted.set(4U, true);
files_wanted.set(5U, false);
expected_files_wanted.set(4U);
expected_files_wanted.unset(5U);
compare_to_expected();
// Prep for the next test: set all files to unwanted
for (tr_file_index_t i = 0U; i < n_files; ++i)
{
files_wanted.set(i, false);
}
expected_files_wanted.set_has_none();
expected_pieces_wanted.set_has_none();
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 code 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(1U, true);
expected_files_wanted.set(1U);
expected_pieces_wanted.set(5U);
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(16U, true);
expected_files_wanted.set(16U);
expected_pieces_wanted.set(10U);
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.set_has_all();
expected_pieces_wanted.set_has_all();
compare_to_expected();
files_wanted.set(std::data(file_indices), std::size(file_indices), false);
expected_files_wanted.set_has_none();
expected_pieces_wanted.set_has_none();
compare_to_expected();
}