base/string16.cc

   1 // Copyright (c) 2009 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 #include "base/string16.h"
   6
   7 #if defined(WCHAR_T_IS_UTF16)
   8
   9 #error This file should not be used on 2-byte wchar_t systems
  10 // If this winds up being needed on 2-byte wchar_t systems, either the
  11 // definitions below can be used, or the host system's wide character
  12 // functions like wmemcmp can be wrapped.
  13
  14 #elif defined(WCHAR_T_IS_UTF32)
  15
  16 #include "base/string_util.h"
  17 #include "base/utf_string_conversions.h"
  18
  19 namespace base {
  20
  21 int c16memcmp(const char16* s1, const char16* s2, size_t n) {
  22   // We cannot call memcmp because that changes the semantics.
  23   while (n-- > 0) {
  24     if (*s1 != *s2) {
  25       // We cannot use (*s1 - *s2) because char16 is unsigned.
  26       return ((*s1 < *s2) ? -1 : 1);
  27     }
  28     ++s1;
  29     ++s2;
  30   }
  31   return 0;
  32 }
  33
  34 size_t c16len(const char16* s) {
  35   const char16 *s_orig = s;
  36   while (*s) {
  37     ++s;
  38   }
  39   return s - s_orig;
  40 }
  41
  42 const char16* c16memchr(const char16* s, char16 c, size_t n) {
  43   while (n-- > 0) {
  44     if (*s == c) {
  45       return s;
  46     }
  47     ++s;
  48   }
  49   return 0;
  50 }
  51
  52 char16* c16memmove(char16* s1, const char16* s2, size_t n) {
  53   return reinterpret_cast<char16*>(memmove(s1, s2, n * sizeof(char16)));
  54 }
  55
  56 char16* c16memcpy(char16* s1, const char16* s2, size_t n) {
  57   return reinterpret_cast<char16*>(memcpy(s1, s2, n * sizeof(char16)));
  58 }
  59
  60 char16* c16memset(char16* s, char16 c, size_t n) {
  61   char16 *s_orig = s;
  62   while (n-- > 0) {
  63     *s = c;
  64     ++s;
  65   }
  66   return s_orig;
  67 }
  68
  69 }  // namespace base
  70
  71 template class std::basic_string<char16, base::string16_char_traits>;
  72
  73 std::ostream& operator<<(std::ostream& out, const string16& str) {
  74   return out << UTF16ToUTF8(str);
  75 }
  76
  77 #endif  // WCHAR_T_IS_UTF32