scintilla/src/UniqueString.cxx

   1 // Scintilla source code edit control
   2 /** @file UniqueString.cxx
   3  ** Define an allocator for UniqueString.
   4  **/
   5 // Copyright 2017 by Neil Hodgson <neilh@scintilla.org>
   6 // The License.txt file describes the conditions under which this software may be distributed.
   7
   8 #include <cstring>
   9 #include <vector>
  10 #include <algorithm>
  11 #include <memory>
  12
  13 #include "UniqueString.h"
  14
  15 namespace Scintilla {
  16
  17 /// Equivalent to strdup but produces a std::unique_ptr<const char[]> allocation to go
  18 /// into collections.
  19 UniqueString UniqueStringCopy(const char *text) {
  20         if (!text) {
  21                 return UniqueString();
  22         }
  23         const size_t len = strlen(text);
  24         std::unique_ptr<char[]> upcNew(new char[len + 1]);
  25         memcpy(&upcNew[0], text, len + 1);
  26         return UniqueString(upcNew.release());
  27 }
  28
  29 // A set of strings that always returns the same pointer for each string.
  30
  31 UniqueStringSet::UniqueStringSet() noexcept = default;
  32
  33 UniqueStringSet::~UniqueStringSet() {
  34         strings.clear();
  35 }
  36
  37 void UniqueStringSet::Clear() noexcept {
  38         strings.clear();
  39 }
  40
  41 const char *UniqueStringSet::Save(const char *text) {
  42         if (!text)
  43                 return nullptr;
  44
  45         for (const UniqueString &us : strings) {
  46                 if (text == us.get()) {
  47                         return us.get();
  48                 }
  49         }
  50
  51         strings.push_back(UniqueStringCopy(text));
  52         return strings.back().get();
  53 }
  54
  55 }