ladybird/Tests/AK/TestMemoryStream.cpp
kleines Filmröllchen 8bcf25561b AK: Fix MemoryStream seek from end
The seek offset is still applied positively when seeking from the end;
see the Kernel's seek implementation.
2023-09-17 17:13:52 -06:00

249 lines
8 KiB
C++

/*
* Copyright (c) 2021, sin-ack <sin-ack@protonmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/MemoryStream.h>
#include <AK/String.h>
#include <LibTest/TestCase.h>
TEST_CASE(allocating_memory_stream_empty)
{
AllocatingMemoryStream stream;
EXPECT_EQ(stream.used_buffer_size(), 0ul);
{
Array<u8, 32> array;
auto read_bytes = MUST(stream.read_some(array));
EXPECT_EQ(read_bytes.size(), 0ul);
}
{
auto offset = MUST(stream.offset_of("test"sv.bytes()));
EXPECT(!offset.has_value());
}
}
TEST_CASE(allocating_memory_stream_offset_of)
{
AllocatingMemoryStream stream;
MUST(stream.write_until_depleted("Well Hello Friends! :^)"sv.bytes()));
{
auto offset = MUST(stream.offset_of(" "sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 4ul);
}
{
auto offset = MUST(stream.offset_of("W"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 0ul);
}
{
auto offset = MUST(stream.offset_of(")"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 22ul);
}
{
auto offset = MUST(stream.offset_of("-"sv.bytes()));
EXPECT(!offset.has_value());
}
MUST(stream.discard(1));
{
auto offset = MUST(stream.offset_of("W"sv.bytes()));
EXPECT(!offset.has_value());
}
{
auto offset = MUST(stream.offset_of("e"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 0ul);
}
}
TEST_CASE(allocating_memory_stream_offset_of_oob)
{
AllocatingMemoryStream stream;
// NOTE: This test is to make sure that offset_of() doesn't read past the end of the "initialized" data.
// So we have to assume some things about the behavior of this class:
// - A chunk is moved to the end when it's fully read from
// - A free chunk is used as-is, no new ones are allocated if one exists.
// First, fill exactly one chunk (in groups of 16 bytes).
for (size_t i = 0; i < AllocatingMemoryStream::CHUNK_SIZE / 16; ++i)
MUST(stream.write_until_depleted("AAAAAAAAAAAAAAAA"sv.bytes()));
// Then discard it all.
MUST(stream.discard(AllocatingMemoryStream::CHUNK_SIZE));
// Now we can write into this chunk again, knowing that it's initialized to all 'A's.
MUST(stream.write_until_depleted("Well Hello Friends! :^)"sv.bytes()));
{
auto offset = MUST(stream.offset_of("A"sv.bytes()));
EXPECT(!offset.has_value());
}
}
TEST_CASE(allocating_memory_stream_offset_of_after_chunk_reorder)
{
AllocatingMemoryStream stream;
// First, fill exactly one chunk (in groups of 16 bytes). This chunk will be reordered.
for (size_t i = 0; i < AllocatingMemoryStream::CHUNK_SIZE / 16; ++i)
MUST(stream.write_until_depleted("AAAAAAAAAAAAAAAA"sv.bytes()));
// Append a few additional bytes to create a second chunk.
MUST(stream.write_until_depleted("BCDEFGHIJKLMNOPQ"sv.bytes()));
// Read back the first chunk, which should reorder it to the end of the list.
// The chunk that we wrote to the second time is now the first one.
MUST(stream.discard(AllocatingMemoryStream::CHUNK_SIZE));
{
auto offset = MUST(stream.offset_of("A"sv.bytes()));
EXPECT(!offset.has_value());
}
{
auto offset = MUST(stream.offset_of("B"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 0ul);
}
{
auto offset = MUST(stream.offset_of("Q"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), 15ul);
}
}
TEST_CASE(allocating_memory_stream_offset_of_with_write_offset_multiple_of_chunk_size)
{
// This tests a specific edge case where we would erroneously trim the last searched block
// to size 0 if the current write offset is a multiple of the chunk size.
AllocatingMemoryStream stream;
// First, fill exactly one chunk (in groups of 16 bytes).
for (size_t i = 0; i < (AllocatingMemoryStream::CHUNK_SIZE / 16) - 1; ++i)
MUST(stream.write_until_depleted("AAAAAAAAAAAAAAAA"sv.bytes()));
MUST(stream.write_until_depleted("BCDEFGHIJKLMNOPQ"sv.bytes()));
// Read a few bytes from the beginning to ensure that we are trying to slice into the zero-sized block.
MUST(stream.discard(32));
{
auto offset = MUST(stream.offset_of("B"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), AllocatingMemoryStream::CHUNK_SIZE - 32 - 16);
}
{
auto offset = MUST(stream.offset_of("Q"sv.bytes()));
EXPECT(offset.has_value());
EXPECT_EQ(offset.value(), AllocatingMemoryStream::CHUNK_SIZE - 32 - 1);
}
}
TEST_CASE(fixed_memory_read_write)
{
constexpr auto some_words = "These are some words"sv;
auto empty = TRY_OR_FAIL(ByteBuffer::create_uninitialized(some_words.length()));
FixedMemoryStream stream { empty.bytes() };
ReadonlyBytes buffer { some_words.characters_without_null_termination(), some_words.length() };
TRY_OR_FAIL(stream.write_some(buffer));
EXPECT_EQ(TRY_OR_FAIL(stream.tell()), some_words.length());
EXPECT(stream.is_eof());
TRY_OR_FAIL(stream.seek(0));
auto contents = TRY_OR_FAIL(stream.read_until_eof());
EXPECT_EQ(contents.bytes(), some_words.bytes());
}
TEST_CASE(fixed_memory_close)
{
auto empty = TRY_OR_FAIL(ByteBuffer::create_uninitialized(64));
FixedMemoryStream stream { empty.bytes() };
EXPECT(stream.is_open());
stream.close();
EXPECT(stream.is_open());
}
TEST_CASE(fixed_memory_read_only)
{
constexpr auto some_words = "These are some words"sv;
FixedMemoryStream stream { ReadonlyBytes { some_words.bytes() } };
auto contents = TRY_OR_FAIL(stream.read_until_eof());
EXPECT_EQ(contents.bytes(), some_words.bytes());
TRY_OR_FAIL(stream.seek(0));
ReadonlyBytes buffer { some_words.characters_without_null_termination(), some_words.length() };
EXPECT_CRASH("Write protection assert", [&] {
(void)stream.write_some(buffer);
return Test::Crash::Failure::DidNotCrash;
});
EXPECT_EQ(TRY_OR_FAIL(stream.tell()), 0ull);
EXPECT(!stream.is_eof());
}
TEST_CASE(fixed_memory_seeking_around)
{
auto stream_buffer = TRY_OR_FAIL(ByteBuffer::create_uninitialized(8702ul));
FixedMemoryStream stream { ReadonlyBytes { stream_buffer.bytes() } };
auto buffer = TRY_OR_FAIL(ByteBuffer::create_uninitialized(16));
TRY_OR_FAIL(stream.seek(500, SeekMode::SetPosition));
EXPECT_EQ(stream.tell().release_value(), 500ul);
TRY_OR_FAIL(stream.read_until_filled(buffer));
TRY_OR_FAIL(stream.seek(234, SeekMode::FromCurrentPosition));
EXPECT_EQ(stream.tell().release_value(), 750ul);
TRY_OR_FAIL(stream.read_until_filled(buffer));
TRY_OR_FAIL(stream.seek(-105, SeekMode::FromEndPosition));
EXPECT_EQ(stream.tell().release_value(), 8597ul);
TRY_OR_FAIL(stream.read_until_filled(buffer));
}
BENCHMARK_CASE(fixed_memory_tell)
{
auto stream_buffer = TRY_OR_FAIL(ByteBuffer::create_uninitialized(10 * KiB));
FixedMemoryStream stream { ReadonlyBytes { stream_buffer.bytes() } };
auto expected_fixed_memory_offset = 0u;
auto ten_byte_buffer = TRY_OR_FAIL(ByteBuffer::create_uninitialized(1));
for (auto i = 0u; i < 4000; ++i) {
TRY_OR_FAIL(stream.read_until_filled(ten_byte_buffer));
expected_fixed_memory_offset += 1u;
EXPECT_EQ(expected_fixed_memory_offset, TRY_OR_FAIL(stream.tell()));
}
for (auto i = 0u; i < 4000; ++i) {
auto seek_fixed_memory_offset = TRY_OR_FAIL(stream.seek(-1, SeekMode::FromCurrentPosition));
expected_fixed_memory_offset -= 1;
EXPECT_EQ(seek_fixed_memory_offset, TRY_OR_FAIL(stream.tell()));
EXPECT_EQ(expected_fixed_memory_offset, TRY_OR_FAIL(stream.tell()));
}
}
TEST_CASE(fixed_memory_truncate)
{
auto stream_buffer = TRY_OR_FAIL(ByteBuffer::create_uninitialized(10 * KiB));
FixedMemoryStream stream { ReadonlyBytes { stream_buffer.bytes() } };
EXPECT(stream.truncate(999).is_error());
}