1 // Copyright 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 #include "base/strings/string16.h"
6
7 #if defined(WCHAR_T_IS_UTF16) && !defined(_AIX)
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 <ostream>
17
18 #include "base/strings/string_piece.h"
19
20 namespace base {
21
c16memcmp(const char16 * s1,const char16 * s2,size_t n)22 int c16memcmp(const char16* s1, const char16* s2, size_t n) {
23 // We cannot call memcmp because that changes the semantics.
24 while (n-- > 0) {
25 if (*s1 != *s2) {
26 // We cannot use (*s1 - *s2) because char16 is unsigned.
27 return ((*s1 < *s2) ? -1 : 1);
28 }
29 ++s1;
30 ++s2;
31 }
32 return 0;
33 }
34
c16len(const char16 * s)35 size_t c16len(const char16* s) {
36 const char16 *s_orig = s;
37 while (*s) {
38 ++s;
39 }
40 return s - s_orig;
41 }
42
c16memchr(const char16 * s,char16 c,size_t n)43 const char16* c16memchr(const char16* s, char16 c, size_t n) {
44 while (n-- > 0) {
45 if (*s == c) {
46 return s;
47 }
48 ++s;
49 }
50 return nullptr;
51 }
52
c16memmove(char16 * s1,const char16 * s2,size_t n)53 char16* c16memmove(char16* s1, const char16* s2, size_t n) {
54 return static_cast<char16*>(memmove(s1, s2, n * sizeof(char16)));
55 }
56
c16memcpy(char16 * s1,const char16 * s2,size_t n)57 char16* c16memcpy(char16* s1, const char16* s2, size_t n) {
58 return static_cast<char16*>(memcpy(s1, s2, n * sizeof(char16)));
59 }
60
c16memset(char16 * s,char16 c,size_t n)61 char16* c16memset(char16* s, char16 c, size_t n) {
62 char16 *s_orig = s;
63 while (n-- > 0) {
64 *s = c;
65 ++s;
66 }
67 return s_orig;
68 }
69
70 namespace string16_internals {
71
operator <<(std::ostream & out,const string16 & str)72 std::ostream& operator<<(std::ostream& out, const string16& str) {
73 return out << base::StringPiece16(str);
74 }
75
PrintTo(const string16 & str,std::ostream * out)76 void PrintTo(const string16& str, std::ostream* out) {
77 *out << str;
78 }
79
80 } // namespace string16_internals
81
82 } // namespace base
83
84 template class std::
85 basic_string<base::char16, base::string16_internals::string16_char_traits>;
86
87 #endif // WCHAR_T_IS_UTF32
88