Files
carbon-lang/toolchain/lexer/tokenized_buffer_fuzzer.cpp
T
Jon Ross-PerkinsandRichard Smith a93e621488 Add vfs support to toolchain. (#2888)
This adds vfs support to the toolchain, allowing Driver to take in-memory inputs in tests. As a consequence, I'm simplifying SourceBuffer: rather than allowing tests to pass in their own memory buffer, I'm using InMemoryFileSystem to push for greater consistency with production code. This does hit a quirk where I need to be careful about null terminator handling because fuzzer imports don't always have one, but that's probably more robust anyways.

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2023-06-12 13:19:57 -07:00

59 lines
2.2 KiB
C++

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include <cstdint>
#include <cstring>
#include "common/check.h"
#include "llvm/ADT/StringRef.h"
#include "toolchain/diagnostics/diagnostic_emitter.h"
#include "toolchain/diagnostics/null_diagnostics.h"
#include "toolchain/lexer/tokenized_buffer.h"
namespace Carbon::Testing {
// NOLINTNEXTLINE: Match the documented fuzzer entry point declaration style.
extern "C" int LLVMFuzzerTestOneInput(const unsigned char* data,
std::size_t size) {
// Ignore large inputs.
// TODO: Investigate replacement with an error limit. Content with errors on
// escaped quotes (`\"` repeated) have O(M * N) behavior for M errors in a
// file length N, so either that will need to also be fixed or M will need to
// shrink for large (1MB+) inputs.
// This also affects parse_tree_fuzzer.cpp.
if (size > 100000) {
return 0;
}
static constexpr llvm::StringLiteral TestFileName = "test.carbon";
llvm::vfs::InMemoryFileSystem fs;
llvm::StringRef data_ref(reinterpret_cast<const char*>(data), size);
CARBON_CHECK(fs.addFile(
TestFileName, /*ModificationTime=*/0,
llvm::MemoryBuffer::getMemBuffer(data_ref, /*BufferName=*/TestFileName,
/*RequiresNullTerminator=*/false)));
auto source = SourceBuffer::CreateFromFile(fs, TestFileName);
auto buffer = TokenizedBuffer::Lex(*source, NullDiagnosticConsumer());
if (buffer.has_errors()) {
return 0;
}
// Walk the lexed and tokenized buffer to ensure it isn't corrupt in some way.
//
// TODO: We should enhance this to do more sanity checks on the resulting
// token stream.
for (TokenizedBuffer::Token token : buffer.tokens()) {
int line_number = buffer.GetLineNumber(token);
CARBON_CHECK(line_number > 0) << "Invalid line number!";
CARBON_CHECK(line_number < INT_MAX) << "Invalid line number!";
int column_number = buffer.GetColumnNumber(token);
CARBON_CHECK(column_number > 0) << "Invalid line number!";
CARBON_CHECK(column_number < INT_MAX) << "Invalid line number!";
}
return 0;
}
} // namespace Carbon::Testing