diff options
Diffstat (limited to 'Libraries/LibJS/Token.cpp')
| -rw-r--r-- | Libraries/LibJS/Token.cpp | 72 |
1 files changed, 67 insertions, 5 deletions
diff --git a/Libraries/LibJS/Token.cpp b/Libraries/LibJS/Token.cpp index ffb95908a5..cc3a1ee0eb 100644 --- a/Libraries/LibJS/Token.cpp +++ b/Libraries/LibJS/Token.cpp @@ -27,6 +27,7 @@ #include "Token.h" #include <AK/Assertions.h> #include <AK/StringBuilder.h> +#include <AK/Utf32View.h> #include <ctype.h> namespace JS { @@ -72,13 +73,26 @@ double Token::double_value() const return strtod(value_string.characters(), nullptr); } -String Token::string_value() const +static u32 hex2int(char x) +{ + ASSERT(isxdigit(x)); + if (x >= '0' && x <= '9') + return x - '0'; + return 10u + (tolower(x) - 'a'); +} + +String Token::string_value(StringValueStatus& status) const { ASSERT(type() == TokenType::StringLiteral || type() == TokenType::TemplateLiteralString); auto is_template = type() == TokenType::TemplateLiteralString; auto offset = type() == TokenType::TemplateLiteralString ? 0 : 1; + auto encoding_failure = [&status](StringValueStatus parse_status) -> String { + status = parse_status; + return {}; + }; + StringBuilder builder; for (size_t i = offset; i < m_value.length() - offset; ++i) { if (m_value[i] == '\\' && i + 1 < m_value.length() - offset) { @@ -114,14 +128,62 @@ String Token::string_value() const case '\\': builder.append('\\'); break; + case 'x': { + if (i + 2 >= m_value.length() - offset) + return encoding_failure(StringValueStatus::MalformedHexEscape); + + auto digit1 = m_value[++i]; + auto digit2 = m_value[++i]; + if (!isxdigit(digit1) || !isxdigit(digit2)) + return encoding_failure(StringValueStatus::MalformedHexEscape); + builder.append(static_cast<char>(hex2int(digit1) * 16 + hex2int(digit2))); + break; + } + case 'u': { + if (i + 1 >= m_value.length() - offset) + return encoding_failure(StringValueStatus::MalformedUnicodeEscape); + u32 code_point = m_value[++i]; + + if (code_point == '{') { + code_point = 0; + do { + if (i + 1 >= m_value.length() - offset) + return encoding_failure(StringValueStatus::MalformedUnicodeEscape); + + auto ch = m_value[++i]; + if (!isxdigit(ch)) + return encoding_failure(StringValueStatus::MalformedUnicodeEscape); + + auto new_code_point = (code_point << 4u) | hex2int(ch); + if (new_code_point < code_point) + return encoding_failure(StringValueStatus::UnicodeEscapeOverflow); + code_point = new_code_point; + } while (m_value[i + 1] != '}'); + ++i; + } else { + if (i + 3 >= m_value.length() - offset || !isxdigit(code_point)) + return encoding_failure(StringValueStatus::MalformedUnicodeEscape); + + code_point = hex2int(code_point); + for (int j = 0; j < 3; ++j) { + auto ch = m_value[++i]; + if (!isxdigit(ch)) + return encoding_failure(StringValueStatus::MalformedUnicodeEscape); + code_point = (code_point << 4u) | hex2int(ch); + } + } + + builder.append({ &code_point, 1 }); + break; + } default: if (is_template && (m_value[i] == '$' || m_value[i] == '`')) { builder.append(m_value[i]); - } else { - // FIXME: Also parse octal, hex and unicode sequences - // should anything else generate a syntax error? - builder.append(m_value[i]); + break; } + + // FIXME: Also parse octal. Should anything else generate a syntax error? + builder.append(m_value[i]); } } else { builder.append(m_value[i]); |