//===- Job.h - Commands to Execute ------------------------------*- 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 LLVM_CLANG_DRIVER_JOB_H

#define LLVM_CLANG_DRIVER_JOB_H

#include "clang/Basic/LLVM.h"

#include "llvm/ADT/ArrayRef.h"

#include "llvm/ADT/Optional.h"

#include "llvm/ADT/SmallVector.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/iterator.h"

#include "llvm/Option/Option.h"

#include "llvm/Support/Program.h"

#include <memory>

#include <string>

#include <utility>

#include <vector>

namespace clang {

namespace driver {

class Action;

class InputInfo;

class Tool;

struct CrashReportInfo {

  StringRef Filename;

  StringRef VFSPath;

  CrashReportInfo(StringRef Filename, StringRef VFSPath)

      : Filename(Filename), VFSPath(VFSPath) {}

};

// Encodes the kind of response file supported for a command invocation.

// Response files are necessary if the command line gets too large, requiring

// the arguments to be transferred to a file.

struct ResponseFileSupport {

  enum ResponseFileKind {

    // Provides full support for response files, which means we can transfer

    // all tool input arguments to a file.

    RF_Full,

    // Input file names can live in a file, but flags can't. This is a special

    // case for old versions of Apple's ld64.

    RF_FileList,

    // Does not support response files: all arguments must be passed via

    // command line.

    RF_None

  };

  /// The level of support for response files.

  ResponseFileKind ResponseKind;

  /// The encoding to use when writing response files on Windows. Ignored on

  /// other host OSes.

  ///

  /// Windows use cases: - GCC and Binutils on mingw only accept ANSI response

  /// files encoded with the system current code page.

  /// - MSVC's CL.exe and LINK.exe accept UTF16 on Windows.

  /// - Clang accepts both UTF8 and UTF16.

  ///

  /// FIXME: When GNU tools learn how to parse UTF16 on Windows, we should

  /// always use UTF16 for Windows, which is the Windows official encoding for

  /// international characters.

  llvm::sys::WindowsEncodingMethod ResponseEncoding;

  /// What prefix to use for the command-line argument when passing a response

  /// file.

  const char *ResponseFlag;

  /// Returns a ResponseFileSupport indicating that response files are not

  /// supported.

  static constexpr ResponseFileSupport None() {

    return {RF_None, llvm::sys::WEM_UTF8, nullptr};

  }

  /// Returns a ResponseFileSupport indicating that response files are

  /// supported, using the @file syntax. On windows, the file is written in the

  /// UTF8 encoding. On other OSes, no re-encoding occurs.

  static constexpr ResponseFileSupport AtFileUTF8() {

    return {RF_Full, llvm::sys::WEM_UTF8, "@"};

  }

  /// Returns a ResponseFileSupport indicating that response files are

  /// supported, using the @file syntax. On windows, the file is written in the

  /// current ANSI code-page encoding. On other OSes, no re-encoding occurs.

  static constexpr ResponseFileSupport AtFileCurCP() {

    return {RF_Full, llvm::sys::WEM_CurrentCodePage, "@"};

  }

  /// Returns a ResponseFileSupport indicating that response files are

  /// supported, using the @file syntax. On windows, the file is written in the

  /// UTF-16 encoding. On other OSes, no re-encoding occurs.

  static constexpr ResponseFileSupport AtFileUTF16() {

    return {RF_Full, llvm::sys::WEM_UTF16, "@"};

  }

};

/// Command - An executable path/name and argument vector to

/// execute.

class Command {

  /// Source - The action which caused the creation of this job.

  const Action &Source;

  /// Tool - The tool which caused the creation of this job.

  const Tool &Creator;

  /// Whether and how to generate response files if the arguments are too long.

  ResponseFileSupport ResponseSupport;

  /// The executable to run.

  const char *Executable;

  /// The list of program arguments (not including the implicit first

  /// argument, which will be the executable).

  llvm::opt::ArgStringList Arguments;

  /// The list of program arguments which are inputs.

  llvm::opt::ArgStringList InputFilenames;

  /// The list of program arguments which are outputs. May be empty.

  std::vector<std::string> OutputFilenames;

  /// Response file name, if this command is set to use one, or nullptr

  /// otherwise

  const char *ResponseFile = nullptr;

  /// The input file list in case we need to emit a file list instead of a

  /// proper response file

  llvm::opt::ArgStringList InputFileList;

  /// String storage if we need to create a new argument to specify a response

  /// file

  std::string ResponseFileFlag;

  /// See Command::setEnvironment

  std::vector<const char *> Environment;

  /// Information on executable run provided by OS.

  mutable Optional<llvm::sys::ProcessStatistics> ProcStat;

  /// When a response file is needed, we try to put most arguments in an

  /// exclusive file, while others remains as regular command line arguments.

  /// This functions fills a vector with the regular command line arguments,

  /// argv, excluding the ones passed in a response file.

  void buildArgvForResponseFile(llvm::SmallVectorImpl<const char *> &Out) const;

  /// Encodes an array of C strings into a single string separated by whitespace.

  /// This function will also put in quotes arguments that have whitespaces and

  /// will escape the regular backslashes (used in Windows paths) and quotes.

  /// The results are the contents of a response file, written into a raw_ostream.

  void writeResponseFile(raw_ostream &OS) const;

public:

  /// Whether to print the input filenames when executing.

  bool PrintInputFilenames = false;

  /// Whether the command will be executed in this process or not.

  bool InProcess = false;

  Command(const Action &Source, const Tool &Creator,

          ResponseFileSupport ResponseSupport, const char *Executable,

          const llvm::opt::ArgStringList &Arguments, ArrayRef<InputInfo> Inputs,

          ArrayRef<InputInfo> Outputs = None);

  // FIXME: This really shouldn't be copyable, but is currently copied in some

  // error handling in Driver::generateCompilationDiagnostics.

  Command(const Command &) = default;

  virtual ~Command() = default;

  virtual void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,

                     CrashReportInfo *CrashInfo = nullptr) const;

  virtual int Execute(ArrayRef<Optional<StringRef>> Redirects,

                      std::string *ErrMsg, bool *ExecutionFailed) const;

  /// getSource - Return the Action which caused the creation of this job.

  const Action &getSource() const { return Source; }

  /// getCreator - Return the Tool which caused the creation of this job.

  const Tool &getCreator() const { return Creator; }

  /// Returns the kind of response file supported by the current invocation.

  const ResponseFileSupport &getResponseFileSupport() {

    return ResponseSupport;

  }

  /// Set to pass arguments via a response file when launching the command

  void setResponseFile(const char *FileName);

  /// Set an input file list, necessary if you specified an RF_FileList response

  /// file support.

  void setInputFileList(llvm::opt::ArgStringList List) {

    InputFileList = std::move(List);

  }

  /// Sets the environment to be used by the new process.

  /// \param NewEnvironment An array of environment variables.

  /// \remark If the environment remains unset, then the environment

  ///         from the parent process will be used.

  virtual void setEnvironment(llvm::ArrayRef<const char *> NewEnvironment);

  const char *getExecutable() const { return Executable; }

  const llvm::opt::ArgStringList &getArguments() const { return Arguments; }

  const llvm::opt::ArgStringList &getInputFilenames() const {

    return InputFilenames;

  }

  const std::vector<std::string> &getOutputFilenames() const {

    return OutputFilenames;

  }

  Optional<llvm::sys::ProcessStatistics> getProcessStatistics() const {

    return ProcStat;

  }

protected:

  /// Optionally print the filenames to be compiled

  void PrintFileNames() const;

};

/// Use the CC1 tool callback when available, to avoid creating a new process

class CC1Command : public Command {

public:

  CC1Command(const Action &Source, const Tool &Creator,

             ResponseFileSupport ResponseSupport, const char *Executable,

             const llvm::opt::ArgStringList &Arguments,

             ArrayRef<InputInfo> Inputs, ArrayRef<InputInfo> Outputs = None);

  void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,

             CrashReportInfo *CrashInfo = nullptr) const override;

  int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,

              bool *ExecutionFailed) const override;

  void setEnvironment(llvm::ArrayRef<const char *> NewEnvironment) override;

};

/// Like Command, but with a fallback which is executed in case

/// the primary command crashes.

class FallbackCommand : public Command {

public:

  FallbackCommand(const Action &Source_, const Tool &Creator_,

                  ResponseFileSupport ResponseSupport, const char *Executable_,

                  const llvm::opt::ArgStringList &Arguments_,

                  ArrayRef<InputInfo> Inputs, ArrayRef<InputInfo> Outputs,

                  std::unique_ptr<Command> Fallback_);

  void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,

             CrashReportInfo *CrashInfo = nullptr) const override;

  int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,

              bool *ExecutionFailed) const override;

private:

  std::unique_ptr<Command> Fallback;

};

/// Like Command, but always pretends that the wrapped command succeeded.

class ForceSuccessCommand : public Command {

public:

  ForceSuccessCommand(const Action &Source_, const Tool &Creator_,

                      ResponseFileSupport ResponseSupport,

                      const char *Executable_,

                      const llvm::opt::ArgStringList &Arguments_,

                      ArrayRef<InputInfo> Inputs,

                      ArrayRef<InputInfo> Outputs = None);

  void Print(llvm::raw_ostream &OS, const char *Terminator, bool Quote,

             CrashReportInfo *CrashInfo = nullptr) const override;

  int Execute(ArrayRef<Optional<StringRef>> Redirects, std::string *ErrMsg,

              bool *ExecutionFailed) const override;

};

/// JobList - A sequence of jobs to perform.

class JobList {

public:

  using list_type = SmallVector<std::unique_ptr<Command>, 4>;

  using size_type = list_type::size_type;

  using iterator = llvm::pointee_iterator<list_type::iterator>;

  using const_iterator = llvm::pointee_iterator<list_type::const_iterator>;

private:

  list_type Jobs;

public:

  void Print(llvm::raw_ostream &OS, const char *Terminator,

             bool Quote, CrashReportInfo *CrashInfo = nullptr) const;

  /// Add a job to the list (taking ownership).

  void addJob(std::unique_ptr<Command> J) { Jobs.push_back(std::move(J)); }

  /// Clear the job list.

  void clear();

  const list_type &getJobs() const { return Jobs; }

  bool empty() const { return Jobs.empty(); }

  size_type size() const { return Jobs.size(); }

  iterator begin() { return Jobs.begin(); }

  const_iterator begin() const { return Jobs.begin(); }

  iterator end() { return Jobs.end(); }

  const_iterator end() const { return Jobs.end(); }

};

} // namespace driver

} // namespace clang

#endif // LLVM_CLANG_DRIVER_JOB_H