llvm-project/llvm/tools/yaml2obj/yaml2obj.cpp

144 lines
4.4 KiB
C++

//===- yaml2obj - Convert YAML to a binary object file --------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This program takes a YAML description of an object file and outputs the
// binary equivalent.
//
// This is used for writing tests that require binary files.
//
//===----------------------------------------------------------------------===//
#include "llvm/ObjectYAML/yaml2obj.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ObjectYAML/ObjectYAML.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Support/WithColor.h"
#include "llvm/Support/YAMLTraits.h"
#include "llvm/Support/raw_ostream.h"
#include <system_error>
using namespace llvm;
namespace {
cl::OptionCategory Cat("yaml2obj Options");
cl::opt<std::string> Input(cl::Positional, cl::desc("<input file>"),
cl::init("-"), cl::cat(Cat));
cl::list<std::string>
D("D", cl::Prefix,
cl::desc("Defined the specified macros to their specified "
"definition. The syntax is <macro>=<definition>"));
cl::opt<unsigned>
DocNum("docnum", cl::init(1),
cl::desc("Read specified document from input (default = 1)"),
cl::cat(Cat));
static cl::opt<uint64_t> MaxSize(
"max-size", cl::init(10 * 1024 * 1024),
cl::desc(
"Sets the maximum allowed output size (0 means no limit) [ELF only]"));
cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
cl::value_desc("filename"), cl::init("-"),
cl::Prefix, cl::cat(Cat));
} // namespace
static Optional<std::string> preprocess(StringRef Buf,
yaml::ErrorHandler ErrHandler) {
DenseMap<StringRef, StringRef> Defines;
for (StringRef Define : D) {
StringRef Macro, Definition;
std::tie(Macro, Definition) = Define.split('=');
if (!Define.count('=') || Macro.empty()) {
ErrHandler("invalid syntax for -D: " + Define);
return {};
}
if (!Defines.try_emplace(Macro, Definition).second) {
ErrHandler("'" + Macro + "'" + " redefined");
return {};
}
}
std::string Preprocessed;
while (!Buf.empty()) {
if (Buf.startswith("[[")) {
size_t I = Buf.find_first_of("[]", 2);
if (Buf.substr(I).startswith("]]")) {
StringRef MacroExpr = Buf.substr(2, I - 2);
StringRef Macro;
StringRef Default;
std::tie(Macro, Default) = MacroExpr.split('=');
// When the -D option is requested, we use the provided value.
// Otherwise we use a default macro value if present.
auto It = Defines.find(Macro);
Optional<StringRef> Value;
if (It != Defines.end())
Value = It->second;
else if (!Default.empty() || MacroExpr.endswith("="))
Value = Default;
if (Value) {
Preprocessed += *Value;
Buf = Buf.substr(I + 2);
continue;
}
}
}
Preprocessed += Buf[0];
Buf = Buf.substr(1);
}
return Preprocessed;
}
int main(int argc, char **argv) {
InitLLVM X(argc, argv);
cl::HideUnrelatedOptions(Cat);
cl::ParseCommandLineOptions(
argc, argv, "Create an object file from a YAML description", nullptr,
nullptr, /*LongOptionsUseDoubleDash=*/true);
auto ErrHandler = [](const Twine &Msg) {
WithColor::error(errs(), "yaml2obj") << Msg << "\n";
};
std::error_code EC;
std::unique_ptr<ToolOutputFile> Out(
new ToolOutputFile(OutputFilename, EC, sys::fs::OF_None));
if (EC) {
ErrHandler("failed to open '" + OutputFilename + "': " + EC.message());
return 1;
}
ErrorOr<std::unique_ptr<MemoryBuffer>> Buf =
MemoryBuffer::getFileOrSTDIN(Input);
if (!Buf)
return 1;
Optional<std::string> Buffer = preprocess(Buf.get()->getBuffer(), ErrHandler);
if (!Buffer)
return 1;
yaml::Input YIn(*Buffer);
if (!convertYAML(YIn, Out->os(), ErrHandler, DocNum,
MaxSize == 0 ? UINT64_MAX : MaxSize))
return 1;
Out->keep();
Out->os().flush();
return 0;
}