llvm-project/lld/COFF/Driver.h

//===- Driver.h -------------------------------------------------*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//

#ifndef LLD_COFF_DRIVER_H
#define LLD_COFF_DRIVER_H

#include "Config.h"
#include "SymbolTable.h"
#include "lld/Common/LLVM.h"
#include "lld/Common/Reproduce.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Object/Archive.h"
#include "llvm/Object/COFF.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/TarWriter.h"
#include <memory>
#include <set>
#include <vector>

namespace lld {
namespace coff {

class LinkerDriver;
extern LinkerDriver *Driver;

using llvm::COFF::MachineTypes;
using llvm::COFF::WindowsSubsystem;
using llvm::Optional;

class COFFOptTable : public llvm::opt::OptTable {
public:
  COFFOptTable();
};

class ArgParser {
public:
  // Concatenate LINK environment variable and given arguments and parse them.
  llvm::opt::InputArgList parseLINK(std::vector<const char *> Args);

  // Tokenizes a given string and then parses as command line options.
  llvm::opt::InputArgList parse(StringRef S) { return parse(tokenize(S)); }

  // Tokenizes a given string and then parses as command line options in
  // .drectve section. /EXPORT options are returned in second element
  // to be processed in fastpath.
  std::pair<llvm::opt::InputArgList, std::vector<StringRef>>
  parseDirectives(StringRef S);

private:
  // Parses command line options.
  llvm::opt::InputArgList parse(llvm::ArrayRef<const char *> Args);

  std::vector<const char *> tokenize(StringRef S);

  COFFOptTable Table;
};

class LinkerDriver {
public:
  void link(llvm::ArrayRef<const char *> Args);

  // Used by the resolver to parse .drectve section contents.
  void parseDirectives(InputFile *File);

  // Used by ArchiveFile to enqueue members.
  void enqueueArchiveMember(const Archive::Child &C, StringRef SymName,
                            StringRef ParentName);

  MemoryBufferRef takeBuffer(std::unique_ptr<MemoryBuffer> MB);

  void enqueuePath(StringRef Path, bool WholeArchive);

private:
  std::unique_ptr<llvm::TarWriter> Tar; // for /linkrepro

  // Opens a file. Path has to be resolved already.
  MemoryBufferRef openFile(StringRef Path);

  // Searches a file from search paths.
  Optional<StringRef> findFile(StringRef Filename);
  Optional<StringRef> findLib(StringRef Filename);
  StringRef doFindFile(StringRef Filename);
  StringRef doFindLib(StringRef Filename);
  StringRef doFindLibMinGW(StringRef Filename);

  // Parses LIB environment which contains a list of search paths.
  void addLibSearchPaths();

  // Library search path. The first element is always "" (current directory).
  std::vector<StringRef> SearchPaths;

  void maybeExportMinGWSymbols(const llvm::opt::InputArgList &Args);

  // We don't want to add the same file more than once.
  // Files are uniquified by their filesystem and file number.
  std::set<llvm::sys::fs::UniqueID> VisitedFiles;

  std::set<std::string> VisitedLibs;

  Symbol *addUndefined(StringRef Sym);

  StringRef mangleMaybe(Symbol *S);

  // Windows specific -- "main" is not the only main function in Windows.
  // You can choose one from these four -- {w,}{WinMain,main}.
  // There are four different entry point functions for them,
  // {w,}{WinMain,main}CRTStartup, respectively. The linker needs to
  // choose the right one depending on which "main" function is defined.
  // This function looks up the symbol table and resolve corresponding
  // entry point name.
  StringRef findDefaultEntry();
  WindowsSubsystem inferSubsystem();

  void addBuffer(std::unique_ptr<MemoryBuffer> MB, bool WholeArchive);
  void addArchiveBuffer(MemoryBufferRef MBRef, StringRef SymName,
                        StringRef ParentName, uint64_t OffsetInArchive);

  void enqueueTask(std::function<void()> Task);
  bool run();

  std::list<std::function<void()>> TaskQueue;
  std::vector<StringRef> FilePaths;
  std::vector<MemoryBufferRef> Resources;

  llvm::StringSet<> DirectivesExports;
};

// Functions below this line are defined in DriverUtils.cpp.

void printHelp(const char *Argv0);

// Parses a string in the form of "<integer>[,<integer>]".
void parseNumbers(StringRef Arg, uint64_t *Addr, uint64_t *Size = nullptr);

void parseGuard(StringRef Arg);

// Parses a string in the form of "<integer>[.<integer>]".
// Minor's default value is 0.
void parseVersion(StringRef Arg, uint32_t *Major, uint32_t *Minor);

// Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
void parseSubsystem(StringRef Arg, WindowsSubsystem *Sys, uint32_t *Major,
                    uint32_t *Minor);

void parseAlternateName(StringRef);
void parseMerge(StringRef);
void parseSection(StringRef);
void parseAligncomm(StringRef);

// Parses a string in the form of "[:<integer>]"
void parseFunctionPadMin(llvm::opt::Arg *A, llvm::COFF::MachineTypes Machine);

// Parses a string in the form of "EMBED[,=<integer>]|NO".
void parseManifest(StringRef Arg);

// Parses a string in the form of "level=<string>|uiAccess=<string>"
void parseManifestUAC(StringRef Arg);

// Parses a string in the form of "cd|net[,(cd|net)]*"
void parseSwaprun(StringRef Arg);

// Create a resource file containing a manifest XML.
std::unique_ptr<MemoryBuffer> createManifestRes();
void createSideBySideManifest();

// Used for dllexported symbols.
Export parseExport(StringRef Arg);
void fixupExports();
void assignExportOrdinals();

// Parses a string in the form of "key=value" and check
// if value matches previous values for the key.
// This feature used in the directive section to reject
// incompatible objects.
void checkFailIfMismatch(StringRef Arg, InputFile *Source);

// Convert Windows resource files (.res files) to a .obj file.
MemoryBufferRef convertResToCOFF(ArrayRef<MemoryBufferRef> MBs);

void runMSVCLinker(std::string Rsp, ArrayRef<StringRef> Objects);

// Create enum with OPT_xxx values for each option in Options.td
enum {
  OPT_INVALID = 0,
#define OPTION(_1, _2, ID, _4, _5, _6, _7, _8, _9, _10, _11, _12) OPT_##ID,
#include "Options.inc"
#undef OPTION
};

} // namespace coff
} // namespace lld

#endif