| 69 | namespace butil { |
| 70 | |
| 71 | bool IsWprintfFormatPortable(const wchar_t* format) { |
| 72 | for (const wchar_t* position = format; *position != '\0'; ++position) { |
| 73 | if (*position == '%') { |
| 74 | bool in_specification = true; |
| 75 | bool modifier_l = false; |
| 76 | while (in_specification) { |
| 77 | // Eat up characters until reaching a known specifier. |
| 78 | if (*++position == '\0') { |
| 79 | // The format string ended in the middle of a specification. Call |
| 80 | // it portable because no unportable specifications were found. The |
| 81 | // string is equally broken on all platforms. |
| 82 | return true; |
| 83 | } |
| 84 | |
| 85 | if (*position == 'l') { |
| 86 | // 'l' is the only thing that can save the 's' and 'c' specifiers. |
| 87 | modifier_l = true; |
| 88 | } else if (((*position == 's' || *position == 'c') && !modifier_l) || |
| 89 | *position == 'S' || *position == 'C' || *position == 'F' || |
| 90 | *position == 'D' || *position == 'O' || *position == 'U') { |
| 91 | // Not portable. |
| 92 | return false; |
| 93 | } |
| 94 | |
| 95 | if (wcschr(L"diouxXeEfgGaAcspn%", *position)) { |
| 96 | // Portable, keep scanning the rest of the format string. |
| 97 | in_specification = false; |
| 98 | } |
| 99 | } |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | return true; |
| 104 | } |
| 105 | |
| 106 | const std::string& EmptyString() { |
| 107 | return EmptyStrings::GetInstance()->s; |