diff options
Diffstat (limited to 'libdevcore/UTF8.cpp')
| -rw-r--r-- | libdevcore/UTF8.cpp | 53 |
1 files changed, 52 insertions, 1 deletions
diff --git a/libdevcore/UTF8.cpp b/libdevcore/UTF8.cpp index 449ccc5d..793bc080 100644 --- a/libdevcore/UTF8.cpp +++ b/libdevcore/UTF8.cpp @@ -27,6 +27,50 @@ namespace dev { +namespace +{ + +/// Validate byte sequence against Unicode chapter 3 Table 3-7. +bool isWellFormed(unsigned char byte1, unsigned char byte2) +{ + switch (byte1) + { + case 0xc0 ... 0xc1: + return false; + case 0xc2 ... 0xdf: + break; + case 0xe0: + if (byte2 < 0xa0) + return false; + break; + case 0xe1 ... 0xec: + break; + case 0xed: + if (byte2 > 0x9f) + return false; + break; + case 0xee ... 0xef: + break; + case 0xf0: + if (byte2 < 0x90) + return false; + break; + case 0xf1 ... 0xf3: + break; + case 0xf4: + if (byte2 > 0x8f) + return false; + break; + case 0xf5 ... 0xf7: + default: + /// Technically anything below 0xc0 or above 0xf7 is + /// not possible to encode using Table 3-6 anyway. + return false; + } + return true; +} + +} bool validateUTF8(std::string const& _input, size_t& _invalidPosition) { @@ -36,6 +80,7 @@ bool validateUTF8(std::string const& _input, size_t& _invalidPosition) for (; i < length; i++) { + // Check for Unicode Chapter 3 Table 3-6 conformity. if ((unsigned char)_input[i] < 0x80) continue; @@ -67,6 +112,13 @@ bool validateUTF8(std::string const& _input, size_t& _invalidPosition) valid = false; break; } + + // Check for Unicode Chapter 3 Table 3-7 conformity. + if ((j == 0) && !isWellFormed(_input[i - 1], _input[i])) + { + valid = false; + break; + } } } @@ -77,5 +129,4 @@ bool validateUTF8(std::string const& _input, size_t& _invalidPosition) return false; } - } |