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mirror of synced 2024-11-25 16:20:23 +01:00
ImHex/lib/libimhex/source/pattern_language/lexer.cpp

535 lines
21 KiB
C++

#include <hex/pattern_language/lexer.hpp>
#include <algorithm>
#include <charconv>
#include <functional>
#include <optional>
#include <vector>
namespace hex::pl {
#define TOKEN(type, value) Token::Type::type, Token::type::value, lineNumber
#define VALUE_TOKEN(type, value) Token::Type::type, value, lineNumber
std::string matchTillInvalid(const char *characters, const std::function<bool(char)> &predicate) {
std::string ret;
while (*characters != 0x00) {
ret += *characters;
characters++;
if (!predicate(*characters))
break;
}
return ret;
}
bool isIdentifierCharacter(char c) {
return std::isalnum(c) || c == '_';
}
size_t getIntegerLiteralLength(std::string_view string) {
auto count = string.find_first_not_of("0123456789ABCDEFabcdef'xXoOpP.uU");
if (count == std::string_view::npos)
return string.size();
else
return count;
}
std::optional<Token::Literal> lexIntegerLiteral(std::string_view string) {
bool hasFloatSuffix = string.ends_with('D') || string.ends_with('F') || string.ends_with('d') || string.ends_with('f');
bool isFloat = std::count(string.begin(), string.end(), '.') == 1 ||
!string.starts_with("0x") && hasFloatSuffix;
if (isFloat) {
// Parse double
char suffix = 0x00;
if (hasFloatSuffix) {
suffix = string.back();
string = string.substr(0, string.length() - 1);
}
char *end = nullptr;
double value = std::strtod(string.begin(), &end);
if (end == string.end()) {
switch (suffix) {
case 'd':
case 'D':
return double(value);
case 'f':
case 'F':
return float(value);
default:
return value;
}
}
} else {
bool isUnsigned = false;
if (string.ends_with('U') || string.ends_with('u')) {
isUnsigned = true;
string = string.substr(0, string.length() - 1);
}
u8 prefixOffset = 0;
u8 base = 10;
if (string.starts_with("0x") || string.starts_with("0X")) {
// Parse hexadecimal
prefixOffset = 2;
base = 16;
} else if (string.starts_with("0o") || string.starts_with("0O")) {
// Parse octal
prefixOffset = 2;
base = 8;
} else if (string.starts_with("0b") || string.starts_with("0B")) {
// Parse binary
prefixOffset = 2;
base = 2;
} else {
// Parse decimal
prefixOffset = 0;
base = 10;
}
u128 value = 0x00;
for (char c : string.substr(prefixOffset)) {
value *= base;
value += [&] {
if (c >= '0' && c <= '9') return c - '0';
else if (c >= 'A' && c <= 'F') return 0xA + (c - 'A');
else if (c >= 'a' && c <= 'f') return 0xA + (c - 'a');
else return 0x00;
}();
}
if (isUnsigned)
return value;
else
return i128(value);
}
return std::nullopt;
}
std::optional<Token::Literal> lexIntegerLiteralWithSeparator(std::string_view string) {
if (string.starts_with('\'') || string.ends_with('\''))
return std::nullopt;
else if (string.find('\'') == std::string_view::npos)
return lexIntegerLiteral(string);
else {
auto preprocessedString = std::string(string);
preprocessedString.erase(std::remove(preprocessedString.begin(), preprocessedString.end(), '\''), preprocessedString.end());
return lexIntegerLiteral(preprocessedString);
}
}
std::optional<std::pair<char, size_t>> getCharacter(const std::string &string) {
if (string.length() < 1)
return std::nullopt;
// Escape sequences
if (string[0] == '\\') {
if (string.length() < 2)
return std::nullopt;
// Handle simple escape sequences
switch (string[1]) {
case 'a':
return {
{'\a', 2}
};
case 'b':
return {
{'\b', 2}
};
case 'f':
return {
{'\f', 2}
};
case 'n':
return {
{'\n', 2}
};
case 'r':
return {
{'\r', 2}
};
case 't':
return {
{'\t', 2}
};
case 'v':
return {
{'\v', 2}
};
case '\\':
return {
{'\\', 2}
};
case '\'':
return {
{'\'', 2}
};
case '\"':
return {
{'\"', 2}
};
}
// Hexadecimal number
if (string[1] == 'x') {
if (string.length() != 4)
return std::nullopt;
if (!isxdigit(string[2]) || !isxdigit(string[3]))
return std::nullopt;
return {
{std::strtoul(&string[2], nullptr, 16), 4}
};
}
// Octal number
if (string[1] == 'o') {
if (string.length() != 5)
return {};
if (string[2] < '0' || string[2] > '7' || string[3] < '0' || string[3] > '7' || string[4] < '0' || string[4] > '7')
return {};
return {
{std::strtoul(&string[2], nullptr, 8), 5}
};
}
return std::nullopt;
} else return {
{string[0], 1}
};
}
std::optional<std::pair<std::string, size_t>> getStringLiteral(const std::string &string) {
if (!string.starts_with('\"'))
return {};
size_t size = 1;
std::string result;
while (string[size] != '\"') {
auto character = getCharacter(string.substr(size));
if (!character.has_value())
return {};
auto &[c, charSize] = character.value();
result += c;
size += charSize;
if (size >= string.length())
return {};
}
return {
{result, size + 1}
};
}
std::optional<std::pair<char, size_t>> getCharacterLiteral(const std::string &string) {
if (string.empty())
return {};
if (string[0] != '\'')
return {};
auto character = getCharacter(string.substr(1));
if (!character.has_value())
return {};
auto &[c, charSize] = character.value();
if (string.length() >= charSize + 2 && string[charSize + 1] != '\'')
return {};
return {
{c, charSize + 2}
};
}
std::optional<std::vector<Token>> Lexer::lex(const std::string &code) {
std::vector<Token> tokens;
u32 offset = 0;
u32 lineNumber = 1;
try {
while (offset < code.length()) {
const char &c = code[offset];
if (c == 0x00)
break;
if (std::isblank(c) || std::isspace(c)) {
if (code[offset] == '\n') lineNumber++;
offset += 1;
} else if (c == ';') {
tokens.emplace_back(TOKEN(Separator, EndOfExpression));
offset += 1;
} else if (c == '(') {
tokens.emplace_back(TOKEN(Separator, RoundBracketOpen));
offset += 1;
} else if (c == ')') {
tokens.emplace_back(TOKEN(Separator, RoundBracketClose));
offset += 1;
} else if (c == '{') {
tokens.emplace_back(TOKEN(Separator, CurlyBracketOpen));
offset += 1;
} else if (c == '}') {
tokens.emplace_back(TOKEN(Separator, CurlyBracketClose));
offset += 1;
} else if (c == '[') {
tokens.emplace_back(TOKEN(Separator, SquareBracketOpen));
offset += 1;
} else if (c == ']') {
tokens.emplace_back(TOKEN(Separator, SquareBracketClose));
offset += 1;
} else if (c == ',') {
tokens.emplace_back(TOKEN(Separator, Comma));
offset += 1;
} else if (c == '.') {
tokens.emplace_back(TOKEN(Separator, Dot));
offset += 1;
} else if (code.substr(offset, 2) == "::") {
tokens.emplace_back(TOKEN(Operator, ScopeResolution));
offset += 2;
} else if (c == '@') {
tokens.emplace_back(TOKEN(Operator, AtDeclaration));
offset += 1;
} else if (code.substr(offset, 2) == "==") {
tokens.emplace_back(TOKEN(Operator, BoolEquals));
offset += 2;
} else if (code.substr(offset, 2) == "!=") {
tokens.emplace_back(TOKEN(Operator, BoolNotEquals));
offset += 2;
} else if (code.substr(offset, 2) == ">=") {
tokens.emplace_back(TOKEN(Operator, BoolGreaterThanOrEquals));
offset += 2;
} else if (code.substr(offset, 2) == "<=") {
tokens.emplace_back(TOKEN(Operator, BoolLessThanOrEquals));
offset += 2;
} else if (code.substr(offset, 2) == "&&") {
tokens.emplace_back(TOKEN(Operator, BoolAnd));
offset += 2;
} else if (code.substr(offset, 2) == "||") {
tokens.emplace_back(TOKEN(Operator, BoolOr));
offset += 2;
} else if (code.substr(offset, 2) == "^^") {
tokens.emplace_back(TOKEN(Operator, BoolXor));
offset += 2;
} else if (c == '=') {
tokens.emplace_back(TOKEN(Operator, Assignment));
offset += 1;
} else if (c == ':') {
tokens.emplace_back(TOKEN(Operator, Inherit));
offset += 1;
} else if (c == '+') {
tokens.emplace_back(TOKEN(Operator, Plus));
offset += 1;
} else if (c == '-') {
tokens.emplace_back(TOKEN(Operator, Minus));
offset += 1;
} else if (c == '*') {
tokens.emplace_back(TOKEN(Operator, Star));
offset += 1;
} else if (c == '/') {
tokens.emplace_back(TOKEN(Operator, Slash));
offset += 1;
} else if (c == '%') {
tokens.emplace_back(TOKEN(Operator, Percent));
offset += 1;
} else if (code.substr(offset, 2) == "<<") {
tokens.emplace_back(TOKEN(Operator, ShiftLeft));
offset += 2;
} else if (code.substr(offset, 2) == ">>") {
tokens.emplace_back(TOKEN(Operator, ShiftRight));
offset += 2;
} else if (c == '>') {
tokens.emplace_back(TOKEN(Operator, BoolGreaterThan));
offset += 1;
} else if (c == '<') {
tokens.emplace_back(TOKEN(Operator, BoolLessThan));
offset += 1;
} else if (c == '!') {
tokens.emplace_back(TOKEN(Operator, BoolNot));
offset += 1;
} else if (c == '|') {
tokens.emplace_back(TOKEN(Operator, BitOr));
offset += 1;
} else if (c == '&') {
tokens.emplace_back(TOKEN(Operator, BitAnd));
offset += 1;
} else if (c == '^') {
tokens.emplace_back(TOKEN(Operator, BitXor));
offset += 1;
} else if (c == '~') {
tokens.emplace_back(TOKEN(Operator, BitNot));
offset += 1;
} else if (c == '?') {
tokens.emplace_back(TOKEN(Operator, TernaryConditional));
offset += 1;
} else if (c == '$') {
tokens.emplace_back(TOKEN(Operator, Dollar));
offset += 1;
} else if (code.substr(offset, 9) == "addressof" && !isIdentifierCharacter(code[offset + 9])) {
tokens.emplace_back(TOKEN(Operator, AddressOf));
offset += 9;
} else if (code.substr(offset, 6) == "sizeof" && !isIdentifierCharacter(code[offset + 6])) {
tokens.emplace_back(TOKEN(Operator, SizeOf));
offset += 6;
} else if (c == '\'') {
auto lexedCharacter = getCharacterLiteral(code.substr(offset));
if (!lexedCharacter.has_value())
throwLexerError("invalid character literal", lineNumber);
auto [character, charSize] = lexedCharacter.value();
tokens.emplace_back(VALUE_TOKEN(Integer, Token::Literal(character)));
offset += charSize;
} else if (c == '\"') {
auto string = getStringLiteral(code.substr(offset));
if (!string.has_value())
throwLexerError("invalid string literal", lineNumber);
auto [s, stringSize] = string.value();
tokens.emplace_back(VALUE_TOKEN(String, Token::Literal(s)));
offset += stringSize;
} else if (isIdentifierCharacter(c) && !std::isdigit(c)) {
std::string identifier = matchTillInvalid(&code[offset], isIdentifierCharacter);
// Check for reserved keywords
if (identifier == "struct")
tokens.emplace_back(TOKEN(Keyword, Struct));
else if (identifier == "union")
tokens.emplace_back(TOKEN(Keyword, Union));
else if (identifier == "using")
tokens.emplace_back(TOKEN(Keyword, Using));
else if (identifier == "enum")
tokens.emplace_back(TOKEN(Keyword, Enum));
else if (identifier == "bitfield")
tokens.emplace_back(TOKEN(Keyword, Bitfield));
else if (identifier == "be")
tokens.emplace_back(TOKEN(Keyword, BigEndian));
else if (identifier == "le")
tokens.emplace_back(TOKEN(Keyword, LittleEndian));
else if (identifier == "if")
tokens.emplace_back(TOKEN(Keyword, If));
else if (identifier == "else")
tokens.emplace_back(TOKEN(Keyword, Else));
else if (identifier == "false")
tokens.emplace_back(VALUE_TOKEN(Integer, Token::Literal(false)));
else if (identifier == "true")
tokens.emplace_back(VALUE_TOKEN(Integer, Token::Literal(true)));
else if (identifier == "parent")
tokens.emplace_back(TOKEN(Keyword, Parent));
else if (identifier == "this")
tokens.emplace_back(TOKEN(Keyword, This));
else if (identifier == "while")
tokens.emplace_back(TOKEN(Keyword, While));
else if (identifier == "for")
tokens.emplace_back(TOKEN(Keyword, For));
else if (identifier == "fn")
tokens.emplace_back(TOKEN(Keyword, Function));
else if (identifier == "return")
tokens.emplace_back(TOKEN(Keyword, Return));
else if (identifier == "namespace")
tokens.emplace_back(TOKEN(Keyword, Namespace));
else if (identifier == "in")
tokens.emplace_back(TOKEN(Keyword, In));
else if (identifier == "out")
tokens.emplace_back(TOKEN(Keyword, Out));
else if (identifier == "break")
tokens.emplace_back(TOKEN(Keyword, Break));
else if (identifier == "continue")
tokens.emplace_back(TOKEN(Keyword, Continue));
// Check for built-in types
else if (identifier == "u8")
tokens.emplace_back(TOKEN(ValueType, Unsigned8Bit));
else if (identifier == "s8")
tokens.emplace_back(TOKEN(ValueType, Signed8Bit));
else if (identifier == "u16")
tokens.emplace_back(TOKEN(ValueType, Unsigned16Bit));
else if (identifier == "s16")
tokens.emplace_back(TOKEN(ValueType, Signed16Bit));
else if (identifier == "u32")
tokens.emplace_back(TOKEN(ValueType, Unsigned32Bit));
else if (identifier == "s32")
tokens.emplace_back(TOKEN(ValueType, Signed32Bit));
else if (identifier == "u64")
tokens.emplace_back(TOKEN(ValueType, Unsigned64Bit));
else if (identifier == "s64")
tokens.emplace_back(TOKEN(ValueType, Signed64Bit));
else if (identifier == "u128")
tokens.emplace_back(TOKEN(ValueType, Unsigned128Bit));
else if (identifier == "s128")
tokens.emplace_back(TOKEN(ValueType, Signed128Bit));
else if (identifier == "float")
tokens.emplace_back(TOKEN(ValueType, Float));
else if (identifier == "double")
tokens.emplace_back(TOKEN(ValueType, Double));
else if (identifier == "char")
tokens.emplace_back(TOKEN(ValueType, Character));
else if (identifier == "char16")
tokens.emplace_back(TOKEN(ValueType, Character16));
else if (identifier == "bool")
tokens.emplace_back(TOKEN(ValueType, Boolean));
else if (identifier == "str")
tokens.emplace_back(TOKEN(ValueType, String));
else if (identifier == "padding")
tokens.emplace_back(TOKEN(ValueType, Padding));
else if (identifier == "auto")
tokens.emplace_back(TOKEN(ValueType, Auto));
// If it's not a keyword and a builtin type, it has to be an identifier
else
tokens.emplace_back(VALUE_TOKEN(Identifier, Token::Identifier(identifier)));
offset += identifier.length();
} else if (std::isdigit(c)) {
auto integerLength = getIntegerLiteralLength(&code[offset]);
auto integer = lexIntegerLiteralWithSeparator(std::string_view(&code[offset], integerLength));
if (!integer.has_value())
throwLexerError("invalid integer literal", lineNumber);
tokens.emplace_back(VALUE_TOKEN(Integer, Token::Literal(integer.value())));
offset += integerLength;
} else
throwLexerError("unknown token", lineNumber);
}
tokens.emplace_back(TOKEN(Separator, EndOfProgram));
} catch (PatternLanguageError &e) {
this->m_error = e;
return std::nullopt;
}
return tokens;
}
}