tools/gn/pattern.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_PATTERN_H_
   6 #define TOOLS_GN_PATTERN_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "tools/gn/value.h"
  12
  13 extern const char kPattern_Help[];
  14
  15 class Pattern {
  16  public:
  17   struct Subrange {
  18     enum Type {
  19       LITERAL,  // Matches exactly the contents of the string.
  20       ANYTHING,  // * (zero or more chars).
  21       PATH_BOUNDARY  // '/' or beginning of string.
  22     };
  23
  24     Subrange(Type t, const std::string& l = std::string())
  25         : type(t),
  26           literal(l) {
  27     }
  28
  29     // Returns the minimum number of chars that this subrange requires.
  30     size_t MinSize() const {
  31       switch (type) {
  32         case LITERAL:
  33           return literal.size();
  34         case ANYTHING:
  35           return 0;
  36         case PATH_BOUNDARY:
  37           return 0;  // Can match beginning or end of string, which is 0 len.
  38         default:
  39           return 0;
  40       }
  41     }
  42
  43     Type type;
  44
  45     // When type == LITERAL this is the text to match.
  46     std::string literal;
  47   };
  48
  49   Pattern(const std::string& s);
  50   ~Pattern();
  51
  52   // Returns true if the current pattern matches the given string.
  53   bool MatchesString(const std::string& s) const;
  54
  55  private:
  56   // allow_implicit_path_boundary determines if a path boundary should accept
  57   // matches at the beginning or end of the string.
  58   bool RecursiveMatch(const std::string& s,
  59                       size_t begin_char,
  60                       size_t subrange_index,
  61                       bool allow_implicit_path_boundary) const;
  62
  63   std::vector<Subrange> subranges_;
  64
  65   // Set to true when the subranges are "*foo" ("ANYTHING" followed by a
  66   // literal). This covers most patterns so we optimize for this.
  67   bool is_suffix_;
  68 };
  69
  70 class PatternList {
  71  public:
  72   PatternList();
  73   ~PatternList();
  74
  75   bool is_empty() const { return patterns_.empty(); }
  76
  77   // Initializes the pattern list from a give list of pattern strings. Sets
  78   // |*err| on failure.
  79   void SetFromValue(const Value& v, Err* err);
  80
  81   bool MatchesString(const std::string& s) const;
  82   bool MatchesValue(const Value& v) const;
  83
  84  private:
  85   std::vector<Pattern> patterns_;
  86 };
  87
  88 #endif  // TOOLS_GN_PATTERN_H_