CPPUtil/UtilString.hpp

   1 //
   2 //  UtilString.hpp
   3 //  CPPUtil
   4 //
   5 //  Created by James McIlree on 4/16/13.
   6 //  Copyright (c) 2013 Apple. All rights reserved.
   7 //
   8
   9 #ifndef CPPUtil_UtilString_hpp
  10 #define CPPUtil_UtilString_hpp
  11
  12 struct ConstCharHash {
  13         //
  14         // Okay, by design std::hash<char*> hashes on the pointer,
  15         // not the contents of that pointer.
  16         //
  17         // The C++11 std::hash<std::string> hash works, but must
  18         // construct a copy of the passed in string to hash.
  19         //
  20         // That's 3x slower than this, minimum.
  21         //
  22         // This is just the __gnu_cxx hash code inlined.
  23         //
  24         std::size_t operator()(const char* __s) const {
  25                 unsigned long __h = 0;
  26                 for ( ; *__s; ++__s)
  27                         __h = 5 * __h + *__s;
  28                 return size_t(__h);
  29         };
  30
  31 };
  32
  33 struct ConstCharEqualTo {
  34         bool operator() (const char* s1, const char* s2) const {
  35                 return strcmp(s1, s2) == 0;
  36         }
  37 };
  38
  39 bool ends_with(std::string& str, std::string postfix);
  40
  41 #endif