tools/gn/source_file.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef TOOLS_GN_SOURCE_FILE_H_
   6 #define TOOLS_GN_SOURCE_FILE_H_
   7
   8 #include <string>
   9
  10 #include "base/containers/hash_tables.h"
  11 #include "base/files/file_path.h"
  12 #include "base/logging.h"
  13 #include "base/strings/string_piece.h"
  14
  15 class SourceDir;
  16
  17 // Represents a file within the source tree. Always begins in a slash, never
  18 // ends in one.
  19 class SourceFile {
  20  public:
  21   SourceFile();
  22
  23   // Takes a known absolute source file. Always begins in a slash.
  24   explicit SourceFile(const base::StringPiece& p);
  25
  26   ~SourceFile();
  27
  28   bool is_null() const { return value_.empty(); }
  29   const std::string& value() const { return value_; }
  30
  31   // Returns everything after the last slash.
  32   std::string GetName() const;
  33   SourceDir GetDir() const;
  34
  35   // Resolves this source file relative to some given source root. Returns
  36   // an empty file path on error.
  37   base::FilePath Resolve(const base::FilePath& source_root) const;
  38
  39   // Returns true if this file starts with a "//" which indicates a path
  40   // from the source root.
  41   bool is_source_absolute() const {
  42     return value_.size() >= 2 && value_[0] == '/' && value_[1] == '/';
  43   }
  44
  45   // Returns true if this file starts with a single slash which indicates a
  46   // system-absolute path.
  47   bool is_system_absolute() const {
  48     return !is_source_absolute();
  49   }
  50
  51   // Returns a source-absolute path starting with only one slash at the
  52   // beginning (normally source-absolute paths start with two slashes to mark
  53   // them as such). This is normally used when concatenating names together.
  54   //
  55   // This function asserts that the file is actually source-absolute. The
  56   // return value points into our buffer.
  57   base::StringPiece SourceAbsoluteWithOneSlash() const {
  58     CHECK(is_source_absolute());
  59     return base::StringPiece(&value_[1], value_.size() - 1);
  60   }
  61
  62   bool operator==(const SourceFile& other) const {
  63     return value_ == other.value_;
  64   }
  65   bool operator!=(const SourceFile& other) const {
  66     return !operator==(other);
  67   }
  68   bool operator<(const SourceFile& other) const {
  69     return value_ < other.value_;
  70   }
  71
  72  private:
  73   friend class SourceDir;
  74
  75   std::string value_;
  76
  77   // Copy & assign supported.
  78 };
  79
  80 namespace BASE_HASH_NAMESPACE {
  81
  82 #if defined(COMPILER_GCC)
  83 template<> struct hash<SourceFile> {
  84   std::size_t operator()(const SourceFile& v) const {
  85     hash<std::string> h;
  86     return h(v.value());
  87   }
  88 };
  89 #elif defined(COMPILER_MSVC)
  90 inline size_t hash_value(const SourceFile& v) {
  91   return hash_value(v.value());
  92 }
  93 #endif  // COMPILER...
  94
  95 }  // namespace BASE_HASH_NAMESPACE
  96
  97 #endif  // TOOLS_GN_SOURCE_FILE_H_