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_DIR_H_ 6 #define TOOLS_GN_SOURCE_DIR_H_ 7 8 #include <algorithm> 9 #include <string> 10 11 #include "base/containers/hash_tables.h" 12 #include "base/files/file_path.h" 13 #include "base/logging.h" 14 #include "base/strings/string_piece.h" 15 16 class SourceFile; 17 18 // Represents a directory within the source tree. Source dirs begin and end in 19 // slashes. 20 // 21 // If there is one slash at the beginning, it will mean a system-absolute file 22 // path. On Windows, absolute system paths will be of the form "/C:/foo/bar". 23 // 24 // Two slashes at the beginning indicate a path relative to the source root. 25 class SourceDir { 26 public: 27 enum SwapIn { SWAP_IN }; 28 29 SourceDir(); 30 explicit SourceDir(const base::StringPiece& p); 31 // Swaps the given string in without copies. The given string will be empty 32 // after this call. 33 SourceDir(SwapIn, std::string* s); 34 ~SourceDir(); 35 36 // Resolves a file or dir name relative to this source directory. Will return 37 // an empty SourceDir/File on error. Empty input is always an error (it's 38 // possible we should say ResolveRelativeDir vs. an empty string should be 39 // the source dir, but we require "." instead). 40 // 41 // If source_root is supplied, these functions will additionally handle the 42 // case where the input is a system-absolute but still inside the source 43 // tree. This is the case for some external tools. 44 SourceFile ResolveRelativeFile( 45 const base::StringPiece& p, 46 const base::StringPiece& source_root = base::StringPiece()) const; 47 SourceDir ResolveRelativeDir( 48 const base::StringPiece& p, 49 const base::StringPiece& source_root = base::StringPiece()) const; 50 51 // Resolves this source file relative to some given source root. Returns 52 // an empty file path on error. 53 base::FilePath Resolve(const base::FilePath& source_root) const; 54 is_null()55 bool is_null() const { return value_.empty(); } value()56 const std::string& value() const { return value_; } 57 58 // Returns true if this path starts with a "//" which indicates a path 59 // from the source root. is_source_absolute()60 bool is_source_absolute() const { 61 return value_.size() >= 2 && value_[0] == '/' && value_[1] == '/'; 62 } 63 64 // Returns true if this path starts with a single slash which indicates a 65 // system-absolute path. is_system_absolute()66 bool is_system_absolute() const { 67 return !is_source_absolute(); 68 } 69 70 // Returns a source-absolute path starting with only one slash at the 71 // beginning (normally source-absolute paths start with two slashes to mark 72 // them as such). This is normally used when concatenating directories 73 // together. 74 // 75 // This function asserts that the directory is actually source-absolute. The 76 // return value points into our buffer. SourceAbsoluteWithOneSlash()77 base::StringPiece SourceAbsoluteWithOneSlash() const { 78 CHECK(is_source_absolute()); 79 return base::StringPiece(&value_[1], value_.size() - 1); 80 } 81 82 void SwapValue(std::string* v); 83 84 bool operator==(const SourceDir& other) const { 85 return value_ == other.value_; 86 } 87 bool operator!=(const SourceDir& other) const { 88 return !operator==(other); 89 } 90 bool operator<(const SourceDir& other) const { 91 return value_ < other.value_; 92 } 93 swap(SourceDir & other)94 void swap(SourceDir& other) { 95 value_.swap(other.value_); 96 } 97 98 private: 99 friend class SourceFile; 100 std::string value_; 101 102 // Copy & assign supported. 103 }; 104 105 namespace BASE_HASH_NAMESPACE { 106 107 #if defined(COMPILER_GCC) 108 template<> struct hash<SourceDir> { 109 std::size_t operator()(const SourceDir& v) const { 110 hash<std::string> h; 111 return h(v.value()); 112 } 113 }; 114 #elif defined(COMPILER_MSVC) 115 inline size_t hash_value(const SourceDir& v) { 116 return hash_value(v.value()); 117 } 118 #endif // COMPILER... 119 120 } // namespace BASE_HASH_NAMESPACE 121 122 inline void swap(SourceDir& lhs, SourceDir& rhs) { 123 lhs.swap(rhs); 124 } 125 126 #endif // TOOLS_GN_SOURCE_DIR_H_ 127