lib/execreq_normalizer.h

// Copyright 2016 The Goma Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.


#ifndef DEVTOOLS_GOMA_LIB_EXECREQ_NORMALIZER_H_
#define DEVTOOLS_GOMA_LIB_EXECREQ_NORMALIZER_H_

#include <map>
#include <string>
#include <vector>

#include "absl/types/optional.h"
#include "base/compiler_specific.h"
#include "lib/flag_parser.h"
#include "lib/path_util.h"
MSVC_PUSH_DISABLE_WARNING_FOR_PROTO()
#include "prototmp/goma_data.pb.h"
MSVC_POP_WARNING()
using std::string;

namespace devtools_goma {

// ExecReqNormalizer is an interface for ExecReq normalization.
class ExecReqNormalizer {
 public:
  virtual ~ExecReqNormalizer() = default;

  // Normalize ExecReq for cache key. |req| will be modified.
  // |id| is used for logging purpose.
  //
  // TODO: Some of the arguments are still compiler-specific. They will
  // be eventually removed. b/79662256
  virtual void NormalizeForCacheKey(
      int id,
      bool normalize_include_path,
      bool is_linking,
      const std::vector<string>& normalize_weak_relative_for_arg,
      const std::map<string, string>& debug_prefix_map,
      ExecReq* req) const = 0;
};

// ConfigurableExecReqNormalizer provides configurable exec req normalizer.
class ConfigurableExecReqNormalizer : public ExecReqNormalizer {
 public:
  // How to disable normalization?
  //   system_include_paths: set |normalize_include_path| false.
  //   args: make |normalize_weak_relative_for_arg| empty.
  //   normalization using fdebug_prefix_map: make |debug_prefix_map| empty.
  void NormalizeForCacheKey(
      int id,
      bool normalize_include_path,
      bool is_linking,
      const std::vector<string>& normalize_weak_relative_for_arg,
      const std::map<string, string>& debug_prefix_map,
      ExecReq* req) const final;

 protected:
  static const int kOmit = 0;
  static const int kNormalizeWithCwd = 1 << 0;
  static const int kNormalizeWithDebugPrefixMap = 1 << 1;
  static const int kPreserveI = 1 << 2;
  static const int kAsIs = 1 << 3;

  struct Config {
    int keep_cwd = kAsIs;
    int keep_args = kAsIs;
    int keep_pathnames_in_input = kAsIs;
    int keep_system_include_dirs = kAsIs;

    // When new_cwd is not nullopt, `cwd` of ExecReq is replaced with `new_cwd`.
    // Also, `new_cwd` can be rewritten by fdebug-prefix-map.
    // But if kAsIs is set in keep_cwd, `new_cwd` is not used.
    absl::optional<string> new_cwd;

    // Returns Config to keep everything as-is.
    static Config AsIs() { return Config(); }
  };

  // Each compiler-specific ExecReqNormalizer will configure this.
  //
  // TODO: Some of the arguments are still compiler-specific. They will
  // be eventually removed. b/79662256
  virtual Config Configure(
      int id,
      const std::vector<string>& args,
      bool normalize_include_path,
      bool is_linking,
      const std::vector<string>& normalize_weak_relative_for_arg,
      const std::map<string, string>& debug_prefix_map,
      const ExecReq* req) const = 0;

 private:
  void NormalizeExecReqSystemIncludeDirs(
      int keep_system_include_dirs,
      const std::map<string, string>& debug_prefix_map,
      const string& debug_prefix_map_signature,
      ExecReq* req) const;
  virtual void NormalizeExecReqArgs(
      int keep_args,
      const std::vector<string>& args,
      const std::vector<string>& normalize_weak_relative_for_arg,
      const std::map<string, string>& debug_prefix_map,
      const string& debug_prefix_map_signature,
      ExecReq* req) const;

  // This method needs cwd and filename in ExecReq_Input.
  // So, do before processing keep_pathnames and keep_cwd.
  void NormalizeExecReqInputOrderForCacheKey(ExecReq* req) const;

  void NormalizeExecReqPathnamesInInput(
      int keep_pathnames_in_input,
      const std::map<string, string>& debug_prefix_map,
      const string& debug_prefix_map_signature,
      ExecReq* req) const;
  void NormalizeExecReqCwd(int keep_cwd,
                           const absl::optional<string>& new_cwd,
                           const std::map<string, string>& debug_prefix_map,
                           const string& debug_prefix_map_signature,
                           ExecReq* req) const;

  void NormalizeExecReqSubprograms(ExecReq* req) const;
  void NormalizeExecReqEnvs(ExecReq* req) const;
  void NormalizeExecReqOutputFilesAndDirs(ExecReq* req) const;
};

class AsIsExecReqNormalizer : public ConfigurableExecReqNormalizer {
 protected:
  Config Configure(int id,
                   const std::vector<string>& args,
                   bool normalize_include_path,
                   bool is_linking,
                   const std::vector<string>& normalize_weak_relative_for_arg,
                   const std::map<string, string>& debug_prefix_map,
                   const ExecReq* req) const override;
};

class FixPathToBeCwdRelative : public FlagParser::Callback {
 public:
  explicit FixPathToBeCwdRelative(string cwd)
      : cwd_(std::move(cwd)), is_fixed_(false) {}
  string ParseFlagValue(const FlagParser::Flag& flag,
                        const string& value) override;
  bool is_fixed() const { return is_fixed_; }

 private:
  const string cwd_;
  bool is_fixed_;
};

class PathRewriterWithDebugPrefixMap : public FlagParser::Callback {
 public:
  explicit PathRewriterWithDebugPrefixMap(
      const std::map<string, string>& debug_prefix_map)
      : debug_prefix_map_(debug_prefix_map),
        is_rewritten_(false),
        removed_fdebug_prefix_map_(false) {}

  string ParseFlagValue(const FlagParser::Flag& flag,
                        const string& value) override;

  bool is_rewritten() const { return is_rewritten_; }
  bool removed_fdebug_prefix_map() const { return removed_fdebug_prefix_map_; }

 private:
  const std::map<string, string>& debug_prefix_map_;
  bool is_rewritten_;
  bool removed_fdebug_prefix_map_;
};

bool RewritePathWithDebugPrefixMap(
    const std::map<string, string>& debug_prefix_map,
    string* path);

bool HasAmbiguityInDebugPrefixMap(
    const std::map<string, string>& debug_prefix_map);

}  // namespace devtools_goma

#endif  // DEVTOOLS_GOMA_LIB_EXECREQ_NORMALIZER_H_