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authorEgor Tensin <Egor.Tensin@gmail.com>2019-12-07 03:36:21 +0300
committerEgor Tensin <Egor.Tensin@gmail.com>2019-12-07 03:36:21 +0300
commit00863566ec4601c65c435b74e575d49546a1c707 (patch)
tree479a0a6e96aba8191c7a65ea9bee2f4d5e3a4aba /server
parentadd stress_test.py (diff)
downloadmath-server-00863566ec4601c65c435b74e575d49546a1c707.tar.gz
math-server-00863566ec4601c65c435b74e575d49546a1c707.zip
split server into multiple components
In a vague attempt to make header files more readable, split server/ into a number of components. Also, refactor the unit tests to use the "Data-driven test cases" of Boost.Test.
Diffstat (limited to 'server')
-rw-r--r--server/CMakeLists.txt15
-rw-r--r--server/common/CMakeLists.txt6
-rw-r--r--server/common/error.hpp (renamed from server/error.hpp)0
-rw-r--r--server/common/log.hpp (renamed from server/log.hpp)0
-rw-r--r--server/lexer.hpp261
-rw-r--r--server/lexer/CMakeLists.txt2
-rw-r--r--server/lexer/error.hpp16
-rw-r--r--server/lexer/input.hpp42
-rw-r--r--server/lexer/lexer.cpp206
-rw-r--r--server/lexer/lexer.hpp61
-rw-r--r--server/lexer/token.cpp71
-rw-r--r--server/lexer/token.hpp49
-rw-r--r--server/lexer/token_type.cpp164
-rw-r--r--server/lexer/token_type.hpp37
-rw-r--r--server/main/CMakeLists.txt13
-rw-r--r--server/main/main.cpp (renamed from server/main.cpp)0
-rw-r--r--server/main/server.cpp (renamed from server/server.cpp)5
-rw-r--r--server/main/server.hpp (renamed from server/server.hpp)0
-rw-r--r--server/main/session.cpp (renamed from server/session.cpp)7
-rw-r--r--server/main/session.hpp (renamed from server/session.hpp)0
-rw-r--r--server/main/session_manager.cpp (renamed from server/session_manager.cpp)3
-rw-r--r--server/main/session_manager.hpp (renamed from server/session_manager.hpp)0
-rw-r--r--server/main/settings.hpp (renamed from server/settings.hpp)0
-rw-r--r--server/parser.hpp168
-rw-r--r--server/parser/CMakeLists.txt2
-rw-r--r--server/parser/error.hpp16
-rw-r--r--server/parser/operator.hpp79
-rw-r--r--server/parser/parser.hpp89
28 files changed, 866 insertions, 446 deletions
diff --git a/server/CMakeLists.txt b/server/CMakeLists.txt
index 7bf356a..4339da2 100644
--- a/server/CMakeLists.txt
+++ b/server/CMakeLists.txt
@@ -1,11 +1,4 @@
-find_package(Boost REQUIRED COMPONENTS filesystem program_options)
-
-option(DEBUG_ASIO "enable debug output for Boost.Asio" OFF)
-
-add_executable(server main.cpp server.cpp session.cpp session_manager.cpp)
-target_include_directories(server SYSTEM PRIVATE ${Boost_INCLUDE_DIRS})
-target_link_libraries(server PRIVATE ${Boost_LIBRARIES})
-
-if(DEBUG_ASIO)
- target_compile_definitions(server PRIVATE BOOST_ASIO_ENABLE_HANDLER_TRACKING)
-endif()
+add_subdirectory(common)
+add_subdirectory(lexer)
+add_subdirectory(parser)
+add_subdirectory(main)
diff --git a/server/common/CMakeLists.txt b/server/common/CMakeLists.txt
new file mode 100644
index 0000000..5655861
--- /dev/null
+++ b/server/common/CMakeLists.txt
@@ -0,0 +1,6 @@
+find_package(Boost REQUIRED)
+
+add_library(common INTERFACE)
+
+target_include_directories(common SYSTEM INTERFACE ${Boost_INCLUDE_DIRS})
+target_link_libraries(common INTERFACE ${Boost_LIBRARIES})
diff --git a/server/error.hpp b/server/common/error.hpp
index cbfbb1e..cbfbb1e 100644
--- a/server/error.hpp
+++ b/server/common/error.hpp
diff --git a/server/log.hpp b/server/common/log.hpp
index ca0fafd..ca0fafd 100644
--- a/server/log.hpp
+++ b/server/common/log.hpp
diff --git a/server/lexer.hpp b/server/lexer.hpp
deleted file mode 100644
index 8afe15c..0000000
--- a/server/lexer.hpp
+++ /dev/null
@@ -1,261 +0,0 @@
-#pragma once
-
-#include "error.hpp"
-
-#include <cmath>
-
-#include <exception>
-#include <functional>
-#include <limits>
-#include <optional>
-#include <regex>
-#include <string>
-#include <string_view>
-#include <unordered_map>
-#include <vector>
-
-namespace math::server {
-namespace lexer {
-
-class Error : public server::Error {
-public:
- explicit Error(const std::string &what)
- : server::Error{"lexer error: " + what}
- { }
-};
-
-class Token {
-public:
- enum class Type {
- LEFT_PAREN,
- RIGHT_PAREN,
- PLUS,
- MINUS,
- ASTERISK,
- SLASH,
- NUMBER,
- };
-
- explicit Token(Type type)
- : m_type{type}, m_number_value{nan()}
- { }
-
- explicit Token(double number_value)
- : m_type{Type::NUMBER}, m_number_value{number_value}
- { }
-
- bool operator==(const Token& other) const {
- return m_type == other.m_type
- && ((is_nan(m_number_value) && is_nan(other.m_number_value))
- || m_number_value == other.m_number_value);
- }
-
- bool operator!=(const Token& other) const { return !(*this == other); }
-
- Type get_type() const { return m_type; }
-
- double get_number_value() const {
- if (get_type() != Type::NUMBER) {
- throw Error{"token must be a number to query its value"};
- }
- return m_number_value;
- }
-
-private:
- static constexpr double nan() { return std::numeric_limits<double>::quiet_NaN(); }
-
- static bool is_nan(double x) { return std::isnan(x); }
-
- Type m_type;
- double m_number_value;
-};
-
-namespace details {
-
-inline std::string_view match_number(const std::string_view& input) {
- static constexpr std::regex::flag_type flags =
- std::regex_constants::ECMAScript |
- std::regex_constants::icase;
- // This is a hacky attempt to describe a C-like grammar for floating-point
- // numbers using a regex (the tests seem to pass though).
- // A proper NFA would be better, I guess.
- static const std::regex number_regex{R"REGEX(^(?:\d+(?:\.\d*)?|\.\d+)(e[+-]?(\d*))?)REGEX", flags};
-
- std::cmatch match;
- if (!std::regex_search(input.cbegin(), input.cend(), match, number_regex)) {
- return {};
- }
- // If we have the numeric part of a number followed by 'e' and no digits,
- // 1) that 'e' definitely belongs to this number token,
- // 2) the user forgot to type in the required digits.
- const auto& exponent = match[1];
- const auto& abs_power = match[2];
- if (exponent.matched && abs_power.matched && abs_power.length() == 0) {
- throw lexer::Error{"exponent has no digits: " + match[0].str()};
- }
- return {match[0].first, match[0].length()};
-}
-
-inline std::optional<double> parse_number(const std::string_view& input, std::string_view& token) {
- const auto view = match_number(input);
- if (!view.data()) {
- return {};
- }
- try {
- const auto result = std::stod(std::string{view});
- token = view;
- return result;
- } catch (const std::exception& e) {
- throw lexer::Error{"couldn't parse number from: " + std::string{view}};
- }
- return {};
-}
-
-inline std::optional<double> parse_number(const std::string_view& input) {
- std::string_view token;
- return parse_number(input, token);
-}
-
-inline bool starts_with(const std::string_view& a, const std::string_view& b) noexcept {
- return a.length() >= b.length()
- && a.compare(0, b.length(), b) == 0;
-}
-
-inline std::optional<Token::Type> parse_const_token(const std::string_view& input, std::string_view& token) {
- // FIXME: Potentially error-prone if there's const token A which is a
- // prefix of token B (if the map is not sorted, we'd parse token A, when it
- // could've been token B).
- // Can be solved by sorting the keys accordingly.
-
- static const std::unordered_map<std::string_view, Token::Type> const_tokens{
- {"(", Token::Type::LEFT_PAREN},
- {")", Token::Type::RIGHT_PAREN},
- {"+", Token::Type::PLUS},
- {"-", Token::Type::MINUS},
- {"*", Token::Type::ASTERISK},
- {"/", Token::Type::SLASH},
- };
-
- for (const auto& it : const_tokens) {
- const auto& str = it.first;
- const auto& type = it.second;
-
- if (starts_with(input, str)) {
- token = input.substr(0, str.length());
- return type;
- }
- }
-
- return {};
-}
-
-inline std::optional<Token::Type> parse_const_token(const std::string_view& input) {
- std::string_view token;
- return parse_const_token(input, token);
-}
-
-inline std::string_view parse_whitespace(const std::string_view& input) {
- static const std::regex ws_regex{R"(\s*)"};
-
- std::cmatch match;
- if (std::regex_search(input.cbegin(), input.cend(), match, ws_regex)) {
- return {match[0].first, match[0].length()};
- }
- return {};
-}
-
-}
-
-}
-
-class Lexer {
-public:
- explicit Lexer(const std::string_view& input)
- : m_input{input} {
- }
-
- using TokenProcessor = std::function<bool (const lexer::Token&)>;
-
- bool for_each_token(const TokenProcessor& process) {
- parse_token();
- for (auto token = peek_token(); token.has_value(); drop_token(), token = peek_token()) {
- if (!process(*token)) {
- return false;
- }
- }
- return true;
- }
-
- std::vector<lexer::Token> get_tokens() {
- std::vector<lexer::Token> tokens;
- for_each_token([&tokens] (const lexer::Token& token) {
- tokens.emplace_back(token);
- return true;
- });
- return tokens;
- }
-
- void parse_token() {
- if (m_input.length() == 0) {
- return;
- }
- std::string_view token_view;
- m_token_buffer = parse_token(token_view);
- if (m_token_buffer.has_value()) {
- m_input.remove_prefix(token_view.length());
- }
- }
-
- bool has_token() const {
- return peek_token().has_value();
- }
-
- std::optional<lexer::Token> peek_token() const {
- return m_token_buffer;
- }
-
- void drop_token() {
- if (!has_token()) {
- throw lexer::Error{"internal: no tokens to drop"};
- }
- m_token_buffer = {};
- parse_token();
- }
-
- std::optional<lexer::Token> drop_token_if(lexer::Token::Type type) {
- if (!has_token()) {
- throw lexer::Error{"internal: no tokens to drop"};
- }
- if (m_token_buffer.value().get_type() != type) {
- return {};
- }
- const auto result = m_token_buffer;
- drop_token();
- return result;
- }
-
-private:
- void consume_whitespace() {
- const auto ws = lexer::details::parse_whitespace(m_input);
- m_input.remove_prefix(ws.length());
- }
-
- std::optional<lexer::Token> parse_token(std::string_view& token_view) {
- consume_whitespace();
- if (m_input.length() == 0) {
- return {};
- }
- if (const auto const_token = lexer::details::parse_const_token(m_input, token_view); const_token.has_value()) {
- return lexer::Token{*const_token};
- }
- if (const auto number = lexer::details::parse_number(m_input, token_view); number.has_value()) {
- return lexer::Token{*number};
- }
- throw lexer::Error{"invalid input at: " + std::string{m_input}};
- }
-
- std::string_view m_input;
- std::optional<lexer::Token> m_token_buffer;
-};
-
-}
diff --git a/server/lexer/CMakeLists.txt b/server/lexer/CMakeLists.txt
new file mode 100644
index 0000000..65523a7
--- /dev/null
+++ b/server/lexer/CMakeLists.txt
@@ -0,0 +1,2 @@
+add_library(lexer lexer.cpp token.cpp token_type.cpp)
+target_link_libraries(lexer PUBLIC common)
diff --git a/server/lexer/error.hpp b/server/lexer/error.hpp
new file mode 100644
index 0000000..99944c7
--- /dev/null
+++ b/server/lexer/error.hpp
@@ -0,0 +1,16 @@
+#pragma once
+
+#include "../common/error.hpp"
+
+#include <string>
+
+namespace math::server {
+
+class LexerError : public Error {
+public:
+ explicit LexerError(const std::string &what)
+ : Error{"lexer error: " + what}
+ { }
+};
+
+}
diff --git a/server/lexer/input.hpp b/server/lexer/input.hpp
new file mode 100644
index 0000000..1104a4b
--- /dev/null
+++ b/server/lexer/input.hpp
@@ -0,0 +1,42 @@
+#pragma once
+
+#include "error.hpp"
+
+#include <cstddef>
+
+#include <string_view>
+
+namespace math::server::lexer {
+
+class Input {
+public:
+ explicit Input(const std::string_view& input)
+ : m_pos{0}, m_input{input}
+ { }
+
+ const std::string_view& get_input() const { return m_input; }
+
+ std::size_t get_pos() const { return m_pos; }
+
+ std::size_t get_length() const { return m_input.length(); }
+
+ bool empty() const { return m_input.empty(); }
+
+ void consume(std::size_t len) {
+ if (m_input.length() < len) {
+ throw LexerError{"internal: not enough input to consume"};
+ }
+ m_pos += len;
+ m_input.remove_prefix(len);
+ }
+
+ void consume(const std::string_view& sub) {
+ consume(sub.length());
+ }
+
+private:
+ std::size_t m_pos;
+ std::string_view m_input;
+};
+
+}
diff --git a/server/lexer/lexer.cpp b/server/lexer/lexer.cpp
new file mode 100644
index 0000000..c7eea6d
--- /dev/null
+++ b/server/lexer/lexer.cpp
@@ -0,0 +1,206 @@
+#include "error.hpp"
+#include "lexer.hpp"
+#include "token.hpp"
+#include "token_type.hpp"
+
+#include <exception>
+#include <optional>
+#include <regex>
+#include <string_view>
+#include <string>
+#include <vector>
+
+namespace math::server {
+namespace lexer {
+namespace {
+
+std::string_view match_number(const std::string_view& input) {
+ static constexpr std::regex::flag_type flags =
+ std::regex_constants::ECMAScript |
+ std::regex_constants::icase;
+ // This is a hacky attempt to describe a C-like grammar for floating-point
+ // numbers using a regex (the tests seem to pass though).
+ // A proper NFA would be better, I guess.
+ static const std::regex number_regex{R"REGEX(^(?:\d+(?:\.\d*)?|\.\d+)(e[+-]?(\d*))?)REGEX", flags};
+
+ std::cmatch match;
+ if (!std::regex_search(input.cbegin(), input.cend(), match, number_regex)) {
+ return {};
+ }
+ {
+ // If we have the numeric part of a number followed by 'e' and no digits,
+ // 1) that 'e' definitely belongs to this number token,
+ // 2) the user forgot to type in the required digits.
+ const auto& exponent = match[1];
+ const auto& abs_power = match[2];
+ if (exponent.matched && abs_power.matched && abs_power.length() == 0) {
+ throw LexerError{"exponent has no digits: " + match[0].str()};
+ }
+ }
+ return {match[0].first, match[0].length()};
+}
+
+std::optional<double> parse_number(const std::string_view& input, std::string_view& token) {
+ const auto view = match_number(input);
+ if (!view.data()) {
+ return {};
+ }
+ try {
+ const auto result = std::stod(std::string{view});
+ token = view;
+ return result;
+ } catch (const std::exception& e) {
+ throw LexerError{"internal: couldn't parse number from: " + std::string{view}};
+ }
+ return {};
+}
+
+bool starts_with(const std::string_view& a, const std::string_view& b) noexcept {
+ return a.length() >= b.length()
+ && a.compare(0, b.length(), b) == 0;
+}
+
+std::optional<token::Type> parse_const_token(const std::string_view& input, std::string_view& token) {
+ for (const auto type : token::const_tokens()) {
+ const auto str = token::type_to_string(type);
+ if (starts_with(input, str)) {
+ token = {input.cbegin(), str.length()};
+ return {type};
+ }
+ }
+ return {};
+}
+
+}
+
+namespace details {
+
+std::optional<double> parse_number(const std::string_view& input) {
+ std::string_view token;
+ return lexer::parse_number(input, token);
+}
+
+std::optional<token::Type> parse_const_token(const std::string_view& input) {
+ std::string_view token;
+ return lexer::parse_const_token(input, token);
+}
+
+std::string_view parse_whitespace(const std::string_view& input) {
+ static const std::regex ws_regex{R"(^\s+)"};
+
+ std::cmatch match;
+ if (std::regex_search(input.cbegin(), input.cend(), match, ws_regex)) {
+ return {match[0].first, match[0].length()};
+ }
+ return {};
+}
+
+}
+}
+
+Lexer::Lexer(const std::string_view& input)
+ : Lexer{lexer::Input{input}} {
+}
+
+Lexer::Lexer(const lexer::Input& input)
+ : m_input{input} {
+
+ consume_token();
+}
+
+bool Lexer::for_each_token(const TokenProcessor& process) {
+ for (auto token = peek_token(); token.has_value(); drop_token(), token = peek_token()) {
+ if (!process(*token)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+std::vector<Lexer::ParsedToken> Lexer::get_tokens() {
+ std::vector<ParsedToken> tokens;
+ for_each_token([&tokens] (const ParsedToken& token) {
+ tokens.emplace_back(token);
+ return true;
+ });
+ return tokens;
+}
+
+void Lexer::drop_token() {
+ if (!has_token()) {
+ throw LexerError{"internal: no tokens to drop"};
+ }
+ m_token_buffer = {};
+ consume_token();
+}
+
+std::optional<Lexer::ParsedToken> Lexer::drop_token_of_type(Type type) {
+ if (!has_token()) {
+ throw LexerError{"internal: no tokens to drop"};
+ }
+ if (m_token_buffer.value().get_type() != type) {
+ return {};
+ }
+ const auto result = m_token_buffer;
+ drop_token();
+ return result;
+}
+
+void Lexer::consume_whitespace() {
+ const auto ws = parse_whitespace();
+ if (!ws.has_value()) {
+ return;
+ }
+ m_input.consume(ws->get_length());
+}
+
+void Lexer::consume_token() {
+ if (m_input.empty()) {
+ return;
+ }
+ consume_whitespace();
+ if (m_input.empty()) {
+ return;
+ }
+ auto token{parse_token()};
+ m_input.consume(token.get_length());
+ m_token_buffer = std::move(token);
+}
+
+std::optional<Lexer::ParsedToken> Lexer::parse_whitespace() const {
+ const auto token_view = lexer::details::parse_whitespace(m_input.get_input());
+ if (token_view.empty()) {
+ return {};
+ }
+ return ParsedToken{Token{Token::Type::WHITESPACE}, m_input.get_pos(), token_view};
+}
+
+std::optional<Lexer::ParsedToken> Lexer::parse_const_token() const {
+ std::string_view token_view;
+ const auto type = lexer::parse_const_token(m_input.get_input(), token_view);
+ if (!type.has_value()) {
+ return {};
+ }
+ return ParsedToken{Token{*type}, m_input.get_pos(), token_view};
+}
+
+std::optional<Lexer::ParsedToken> Lexer::parse_number() const {
+ std::string_view token_view;
+ const auto number = lexer::parse_number(m_input.get_input(), token_view);
+ if (!number.has_value()) {
+ return {};
+ }
+ return ParsedToken{Token{*number}, m_input.get_pos(), token_view};
+}
+
+Lexer::ParsedToken Lexer::parse_token() const {
+ if (const auto const_token = parse_const_token(); const_token.has_value()) {
+ return *const_token;
+ }
+ if (const auto number = parse_number(); number.has_value()) {
+ return *number;
+ }
+ throw LexerError{"invalid input at: " + std::string{m_input.get_input()}};
+}
+
+}
diff --git a/server/lexer/lexer.hpp b/server/lexer/lexer.hpp
new file mode 100644
index 0000000..d08a2df
--- /dev/null
+++ b/server/lexer/lexer.hpp
@@ -0,0 +1,61 @@
+#pragma once
+
+#include "input.hpp"
+#include "token.hpp"
+#include "token_type.hpp"
+
+#include <functional>
+#include <optional>
+#include <string_view>
+#include <vector>
+
+namespace math::server {
+namespace lexer::details {
+
+// Exposed for testing:
+std::string_view parse_whitespace(const std::string_view&);
+std::optional<double> parse_number(const std::string_view&);
+std::optional<token::Type> parse_const_token(const std::string_view&);
+
+}
+
+class Lexer {
+public:
+ explicit Lexer(const std::string_view& input);
+ explicit Lexer(const lexer::Input& input);
+
+ using Token = lexer::Token;
+ using ParsedToken = lexer::ParsedToken;
+ using Type = Token::Type;
+ using TokenProcessor = std::function<bool (const ParsedToken&)>;
+
+ bool for_each_token(const TokenProcessor& process);
+
+ std::vector<ParsedToken> get_tokens();
+
+ bool has_token() const {
+ return peek_token().has_value();
+ }
+
+ std::optional<ParsedToken> peek_token() const {
+ return m_token_buffer;
+ }
+
+ void drop_token();
+ std::optional<ParsedToken> drop_token_of_type(Type type);
+
+private:
+ std::optional<ParsedToken> parse_whitespace() const;
+ std::optional<ParsedToken> parse_const_token() const;
+ std::optional<ParsedToken> parse_number() const;
+
+ ParsedToken parse_token() const;
+
+ void consume_whitespace();
+ void consume_token();
+
+ lexer::Input m_input;
+ std::optional<ParsedToken> m_token_buffer;
+};
+
+}
diff --git a/server/lexer/token.cpp b/server/lexer/token.cpp
new file mode 100644
index 0000000..6ffb721
--- /dev/null
+++ b/server/lexer/token.cpp
@@ -0,0 +1,71 @@
+#include "error.hpp"
+#include "token.hpp"
+#include "token_type.hpp"
+
+#include <cmath>
+
+#include <limits>
+#include <variant>
+
+namespace math::server::lexer {
+namespace {
+
+static constexpr double nan() { return std::numeric_limits<double>::quiet_NaN(); }
+
+static bool is_nan(double x) { return std::isnan(x); }
+
+static bool numbers_equal(double x, double y) {
+ if (is_nan(x) && is_nan(y)) {
+ return true;
+ }
+ return x == y;
+}
+
+}
+
+Token::Token(Type type)
+ : m_type{type} {
+
+ if (token::token_has_value(type)) {
+ throw LexerError{"internal: must have a value: " + token::type_to_int_string(type)};
+ }
+}
+
+Token::Token(double value)
+ : m_type{Type::NUMBER}, m_value{value}
+{ }
+
+bool Token::operator==(const Token& other) const {
+ if (m_type != other.m_type) {
+ return false;
+ }
+ if (token::is_const_token(m_type)) {
+ return true;
+ }
+ if (m_type == Type::NUMBER) {
+ return numbers_equal(as_number(), other.as_number());
+ }
+ throw LexerError{"internal: can't compare tokens of type: " + token::type_to_int_string(m_type)};
+}
+
+double Token::as_number() const {
+ const auto type = get_type();
+ if (type != Type::NUMBER) {
+ throw LexerError{"internal: not a number: " + token::type_to_int_string(type)};
+ }
+ return std::get<double>(m_value);
+}
+
+std::ostream& operator<<(std::ostream& os, const Token& token) {
+ switch (token.m_type) {
+ case token::Type::NUMBER:
+ os << token.as_number();
+ break;
+ default:
+ os << token::type_to_string(token.m_type);
+ break;
+ }
+ return os;
+}
+
+}
diff --git a/server/lexer/token.hpp b/server/lexer/token.hpp
new file mode 100644
index 0000000..6f98383
--- /dev/null
+++ b/server/lexer/token.hpp
@@ -0,0 +1,49 @@
+#pragma once
+
+#include "token_type.hpp"
+
+#include <cstddef>
+
+#include <string_view>
+#include <utility>
+#include <variant>
+
+namespace math::server::lexer {
+
+class Token {
+public:
+ using Type = token::Type;
+
+ explicit Token(token::Type type);
+ explicit Token(double value);
+
+ bool operator==(const Token& other) const;
+ bool operator!=(const Token& other) const { return !(*this == other); }
+
+ Type get_type() const { return m_type; }
+
+ double as_number() const;
+
+private:
+ token::Type m_type;
+ std::variant<double> m_value;
+
+ friend std::ostream& operator<<(std::ostream&, const Token&);
+};
+
+class ParsedToken : public Token {
+public:
+ ParsedToken(Token&& token, std::size_t pos, const std::string_view& view)
+ : Token{std::move(token)}, m_pos{pos}, m_view{view} {
+ }
+
+ std::size_t get_pos() const { return m_pos; }
+
+ std::size_t get_length() const { return m_view.length(); }
+
+private:
+ std::size_t m_pos;
+ std::string_view m_view;
+};
+
+}
diff --git a/server/lexer/token_type.cpp b/server/lexer/token_type.cpp
new file mode 100644
index 0000000..9a69ba1
--- /dev/null
+++ b/server/lexer/token_type.cpp
@@ -0,0 +1,164 @@
+#include "error.hpp"
+#include "token_type.hpp"
+
+#include <functional>
+#include <map>
+#include <ostream>
+#include <stdexcept>
+#include <string>
+#include <unordered_map>
+
+namespace math::server::lexer::token {
+namespace {
+
+using ToStringMap = std::unordered_map<Type, std::string>;
+using FromStringMap = std::map<std::string, Type, std::greater<std::string>>;
+
+class ToStringConverter {
+public:
+ ToStringConverter() : m_map{to_string_map()} {
+ validate();
+ }
+
+ const ToStringMap& map() const { return m_map; }
+
+private:
+ static const ToStringMap& to_string_map() {
+ static const ToStringMap map{
+ {Type::WHITESPACE, "whitespace"},
+ {Type::PLUS, "+"},
+ {Type::MINUS, "-"},
+ {Type::ASTERISK, "*"},
+ {Type::SLASH, "/"},
+ {Type::LEFT_PAREN, "("},
+ {Type::RIGHT_PAREN, ")"},
+ {Type::NUMBER, "number"},
+ };
+ return map;
+ }
+
+ void validate() const {
+ check_for_duplicates();
+ }
+
+ void check_for_duplicates() const {
+ std::unordered_set<std::string> strings;
+ for (const auto& [type, str] : m_map) {
+ const auto [_, inserted] = strings.emplace(str);
+ if (!inserted) {
+ throw std::logic_error{"multiple tokens have the same string representation: " + str};
+ }
+ }
+ }
+
+ const ToStringMap& m_map;
+};
+
+const ToStringMap& to_string_map() {
+ static const ToStringConverter converter;
+ return converter.map();
+}
+
+class FromStringConverter {
+public:
+ FromStringConverter(const ToStringMap& to_string)
+ : m_map{build_map(to_string)} {
+ }
+
+ const FromStringMap& map() const { return m_map; }
+
+private:
+ static FromStringMap build_map(const ToStringMap& to_string) {
+ FromStringMap from_string;
+ for (const auto& [type, str] : to_string) {
+ const auto [_, inserted] = from_string.emplace(str, type);
+ if (!inserted) {
+ throw std::logic_error{"multiple tokens have the same string representation: " + str};
+ }
+ }
+ return from_string;
+ }
+
+ FromStringMap m_map;
+};
+
+const FromStringMap& from_string_map() {
+ static const FromStringConverter converter{to_string_map()};
+ return converter.map();
+}
+
+class ConstTokens {
+public:
+ ConstTokens() {
+ const auto& map = to_string_map();
+ for (const auto& [type, _] : map) {
+ if (is_const_token(type)) {
+ m_set.emplace(type);
+ }
+ }
+ }
+
+ const TypeSet& set() const { return m_set; }
+
+private:
+ TypeSet m_set;
+};
+
+}
+
+TypeInt type_to_int(Type type) {
+ return static_cast<TypeInt>(type);
+}
+
+std::string type_to_int_string(Type type) {
+ return std::to_string(type_to_int(type));
+}
+
+bool is_const_token(Type type) {
+ switch (type) {
+ case Type::WHITESPACE:
+ case Type::NUMBER:
+ return false;
+ default:
+ return true;
+ }
+}
+
+const TypeSet& const_tokens() {
+ static const ConstTokens tokens;
+ return tokens.set();
+}
+
+bool token_has_value(Type type) {
+ switch (type) {
+ case Type::NUMBER:
+ return true;
+ default:
+ return false;
+ }
+}
+
+std::string type_to_string(Type type) {
+ const auto& map = to_string_map();
+ const auto it = map.find(type);
+ if (it == map.cend()) {
+ throw LexerError{"type_to_string: unsupported token type: " + type_to_int_string(type)};
+ }
+ return it->second;
+}
+
+Type type_from_string(const std::string& src) {
+ const auto& map = from_string_map();
+ const auto it = map.find(src);
+ if (it == map.cend()) {
+ throw LexerError{"type_from_string: unsupported token: " + std::string{src}};
+ }
+ return it->second;
+}
+
+std::ostream& operator<<(std::ostream& os, const Type& type) {
+ os << type_to_int(type);
+ return os;
+}
+
+}
diff --git a/server/lexer/token_type.hpp b/server/lexer/token_type.hpp
new file mode 100644
index 0000000..9489915
--- /dev/null
+++ b/server/lexer/token_type.hpp
@@ -0,0 +1,37 @@
+#pragma once
+
+#include <ostream>
+#include <string>
+#include <type_traits>
+#include <unordered_set>
+
+namespace math::server::lexer::token {
+
+enum class Type {
+ WHITESPACE,
+ PLUS,
+ MINUS,
+ ASTERISK,
+ SLASH,
+ LEFT_PAREN,
+ RIGHT_PAREN,
+ NUMBER,
+};
+
+using TypeInt = std::underlying_type<Type>::type;
+using TypeSet = std::unordered_set<Type>;
+
+TypeInt type_to_int(Type);
+std::string type_to_int_string(Type);
+
+bool is_const_token(Type);
+const TypeSet& const_tokens();
+
+bool token_has_value(Type);
+
+std::string type_to_string(Type);
+Type type_from_string(const std::string&);
+
+std::ostream& operator<<(std::ostream&, const Type&);
+
+}
diff --git a/server/main/CMakeLists.txt b/server/main/CMakeLists.txt
new file mode 100644
index 0000000..b322390
--- /dev/null
+++ b/server/main/CMakeLists.txt
@@ -0,0 +1,13 @@
+find_package(Boost REQUIRED COMPONENTS filesystem program_options)
+
+option(DEBUG_ASIO "enable debug output for Boost.Asio" OFF)
+
+add_executable(server main.cpp server.cpp session.cpp session_manager.cpp)
+target_link_libraries(server PRIVATE common parser)
+
+target_include_directories(server SYSTEM PRIVATE ${Boost_INCLUDE_DIRS})
+target_link_libraries(server PRIVATE ${Boost_LIBRARIES})
+
+if(DEBUG_ASIO)
+ target_compile_definitions(server PRIVATE BOOST_ASIO_ENABLE_HANDLER_TRACKING)
+endif()
diff --git a/server/main.cpp b/server/main/main.cpp
index 2cf6d35..2cf6d35 100644
--- a/server/main.cpp
+++ b/server/main/main.cpp
diff --git a/server/server.cpp b/server/main/server.cpp
index 4dc672c..3800144 100644
--- a/server/server.cpp
+++ b/server/main/server.cpp
@@ -1,10 +1,11 @@
-#include "error.hpp"
-#include "log.hpp"
#include "server.hpp"
#include "session.hpp"
#include "session_manager.hpp"
#include "settings.hpp"
+#include "../common/error.hpp"
+#include "../common/log.hpp"
+
#include <boost/asio.hpp>
#include <boost/system/error_code.hpp>
#include <boost/system/system_error.hpp>
diff --git a/server/server.hpp b/server/main/server.hpp
index 5524f88..5524f88 100644
--- a/server/server.hpp
+++ b/server/main/server.hpp
diff --git a/server/session.cpp b/server/main/session.cpp
index 409ca5a..0ee7f75 100644
--- a/server/session.cpp
+++ b/server/main/session.cpp
@@ -1,9 +1,10 @@
-#include "error.hpp"
-#include "log.hpp"
-#include "parser.hpp"
#include "session.hpp"
#include "session_manager.hpp"
+#include "../common/error.hpp"
+#include "../common/log.hpp"
+#include "../parser/parser.hpp"
+
#include <boost/asio.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/system/error_code.hpp>
diff --git a/server/session.hpp b/server/main/session.hpp
index ace3755..ace3755 100644
--- a/server/session.hpp
+++ b/server/main/session.hpp
diff --git a/server/session_manager.cpp b/server/main/session_manager.cpp
index a42fca4..c2aef6d 100644
--- a/server/session_manager.cpp
+++ b/server/main/session_manager.cpp
@@ -1,7 +1,8 @@
-#include "log.hpp"
#include "session.hpp"
#include "session_manager.hpp"
+#include "../common/log.hpp"
+
#include <memory>
#include <mutex>
diff --git a/server/session_manager.hpp b/server/main/session_manager.hpp
index f0bec0b..f0bec0b 100644
--- a/server/session_manager.hpp
+++ b/server/main/session_manager.hpp
diff --git a/server/settings.hpp b/server/main/settings.hpp
index 310163f..310163f 100644
--- a/server/settings.hpp
+++ b/server/main/settings.hpp
diff --git a/server/parser.hpp b/server/parser.hpp
deleted file mode 100644
index a9e5f54..0000000
--- a/server/parser.hpp
+++ /dev/null
@@ -1,168 +0,0 @@
-#pragma once
-
-#include "error.hpp"
-#include "lexer.hpp"
-
-#include <optional>
-#include <string>
-#include <string_view>
-
-namespace math::server {
-namespace parser {
-
-class Error : public server::Error {
-public:
- explicit Error(const std::string& what)
- : server::Error{"parser error: " + what}
- { }
-};
-
-class BinaryOp {
-public:
- static bool is(const lexer::Token& token) {
- using Type = lexer::Token::Type;
- switch (token.get_type()) {
- case Type::PLUS:
- case Type::MINUS:
- case Type::ASTERISK:
- case Type::SLASH:
- return true;
-
- default:
- return false;
- }
- }
-
- static BinaryOp from_token(const lexer::Token& token) {
- if (!is(token)) {
- throw Error{"internal: token is not a binary operator"};
- }
- return BinaryOp{token};
- }
-
- static constexpr unsigned min_precedence() { return 0; }
-
- unsigned get_precedence() const {
- using Type = lexer::Token::Type;
- switch (m_type) {
- case Type::PLUS:
- case Type::MINUS:
- return min_precedence();
-
- case Type::ASTERISK:
- case Type::SLASH:
- return min_precedence() + 1;
-
- default:
- throw Error{"internal: undefined operator precedence"};
- }
- }
-
- double exec(double lhs, double rhs) const {
- using Type = lexer::Token::Type;
- switch (m_type) {
- case Type::PLUS:
- return lhs + rhs;
- case Type::MINUS:
- return lhs - rhs;
- case Type::ASTERISK:
- return lhs * rhs;
- case Type::SLASH:
- // Trapping the CPU would be better?
- if (rhs == 0.) {
- throw Error{"division by zero"};
- }
- return lhs / rhs;
- default:
- throw Error{"internal: unsupported operator"};
- }
- }
-
-private:
- explicit BinaryOp(const lexer::Token& token)
- : m_type{token.get_type()}
- { }
-
- lexer::Token::Type m_type;
-};
-
-}
-
-class Parser {
-public:
- // I did simple recursive descent parsing a long time ago (see
- // https://github.com/egor-tensin/simple-interpreter), this appears to be
- // a finer algorithm for parsing arithmetic expressions.
- // Reference: https://en.wikipedia.org/wiki/Operator-precedence_parser
-
- explicit Parser(const std::string_view& input)
- : m_lexer{input}
- { }
-
- double exec() {
- m_lexer.parse_token();
- const auto result = exec_expr();
- if (m_lexer.has_token()) {
- throw parser::Error{"expected a binary operator"};
- }
- return result;
- }
-
-private:
- double exec_expr() {
- return exec_expr(exec_primary(), parser::BinaryOp::min_precedence());
- }
-
- double exec_expr(double lhs, unsigned min_prec) {
- for (auto op = peek_operator(); op.has_value() && op->get_precedence() >= min_prec;) {
- const auto lhs_op = *op;
- m_lexer.drop_token();
- auto rhs = exec_primary();
-
- for (op = peek_operator(); op.has_value() && op->get_precedence() > lhs_op.get_precedence(); op = peek_operator()) {
- rhs = exec_expr(rhs, op->get_precedence());
- }
-
- lhs = lhs_op.exec(lhs, rhs);
- }
- return lhs;
- }
-
- std::optional<parser::BinaryOp> peek_operator() {
- const auto token = m_lexer.peek_token();
- if (!token.has_value() || !parser::BinaryOp::is(*token)) {
- return {};
- }
- return parser::BinaryOp::from_token(*token);
- }
-
- double exec_primary() {
- if (!m_lexer.has_token()) {
- throw parser::Error{"expected '-', '(' or a number"};
- }
-
- using Type = lexer::Token::Type;
-
- if (m_lexer.drop_token_if(Type::MINUS).has_value()) {
- return -exec_primary();
- }
-
- if (m_lexer.drop_token_if(Type::LEFT_PAREN).has_value()) {
- const auto inner = exec_expr();
- if (!m_lexer.has_token() || !m_lexer.drop_token_if(Type::RIGHT_PAREN).has_value()) {
- throw parser::Error{"missing closing ')'"};
- }
- return inner;
- }
-
- if (const auto token = m_lexer.drop_token_if(Type::NUMBER); token.has_value()) {
- return token.value().get_number_value();
- }
-
- throw parser::Error{"expected '-', '(' or a number"};
- }
-
- Lexer m_lexer;
-};
-
-}
diff --git a/server/parser/CMakeLists.txt b/server/parser/CMakeLists.txt
new file mode 100644
index 0000000..2490e57
--- /dev/null
+++ b/server/parser/CMakeLists.txt
@@ -0,0 +1,2 @@
+add_library(parser INTERFACE)
+target_link_libraries(parser INTERFACE common lexer)
diff --git a/server/parser/error.hpp b/server/parser/error.hpp
new file mode 100644
index 0000000..1ba29ed
--- /dev/null
+++ b/server/parser/error.hpp
@@ -0,0 +1,16 @@
+#pragma once
+
+#include "../common/error.hpp"
+
+#include <string>
+
+namespace math::server {
+
+class ParserError : public Error {
+public:
+ explicit ParserError(const std::string& what)
+ : Error{"parser error: " + what}
+ { }
+};
+
+}
diff --git a/server/parser/operator.hpp b/server/parser/operator.hpp
new file mode 100644
index 0000000..4226078
--- /dev/null
+++ b/server/parser/operator.hpp
@@ -0,0 +1,79 @@
+#pragma once
+
+#include "error.hpp"
+
+#include "../lexer/token.hpp"
+#include "../lexer/token_type.hpp"
+
+namespace math::server::parser {
+
+class BinaryOp {
+public:
+ using Token = lexer::Token;
+ using Type = Token::Type;
+
+ static bool is(const Token& token) {
+ switch (token.get_type()) {
+ case Type::PLUS:
+ case Type::MINUS:
+ case Type::ASTERISK:
+ case Type::SLASH:
+ return true;
+
+ default:
+ return false;
+ }
+ }
+
+ static BinaryOp from_token(const Token& token) {
+ if (!is(token)) {
+ throw ParserError{"internal: token is not a binary operator"};
+ }
+ return BinaryOp{token};
+ }
+
+ static constexpr unsigned min_precedence() { return 0; }
+
+ unsigned get_precedence() const {
+ switch (m_type) {
+ case Type::PLUS:
+ case Type::MINUS:
+ return min_precedence();
+
+ case Type::ASTERISK:
+ case Type::SLASH:
+ return min_precedence() + 1;
+
+ default:
+ throw ParserError{"internal: undefined operator precedence"};
+ }
+ }
+
+ double exec(double lhs, double rhs) const {
+ switch (m_type) {
+ case Type::PLUS:
+ return lhs + rhs;
+ case Type::MINUS:
+ return lhs - rhs;
+ case Type::ASTERISK:
+ return lhs * rhs;
+ case Type::SLASH:
+ // Trapping the CPU would be better?
+ if (rhs == 0.) {
+ throw ParserError{"division by zero"};
+ }
+ return lhs / rhs;
+ default:
+ throw ParserError{"internal: unsupported operator"};
+ }
+ }
+
+private:
+ explicit BinaryOp(const Token& token)
+ : m_type{token.get_type()}
+ { }
+
+ Type m_type;
+};
+
+}
diff --git a/server/parser/parser.hpp b/server/parser/parser.hpp
new file mode 100644
index 0000000..1197c31
--- /dev/null
+++ b/server/parser/parser.hpp
@@ -0,0 +1,89 @@
+#pragma once
+
+#include "error.hpp"
+#include "operator.hpp"
+
+#include "../lexer/lexer.hpp"
+
+#include <optional>
+#include <string_view>
+
+namespace math::server {
+
+class Parser {
+public:
+ // I did simple recursive descent parsing a long time ago (see
+ // https://github.com/egor-tensin/simple-interpreter), this appears to be
+ // a finer algorithm for parsing arithmetic expressions.
+ // Reference: https://en.wikipedia.org/wiki/Operator-precedence_parser
+
+ explicit Parser(const std::string_view& input)
+ : m_lexer{input}
+ { }
+
+ double exec() {
+ const auto result = exec_expr();
+ if (m_lexer.has_token()) {
+ throw ParserError{"expected a binary operator"};
+ }
+ return result;
+ }
+
+private:
+ double exec_expr() {
+ return exec_expr(exec_primary(), parser::BinaryOp::min_precedence());
+ }
+
+ double exec_expr(double lhs, unsigned min_prec) {
+ for (auto op = peek_operator(); op.has_value() && op->get_precedence() >= min_prec;) {
+ const auto lhs_op = *op;
+ m_lexer.drop_token();
+ auto rhs = exec_primary();
+
+ for (op = peek_operator(); op.has_value() && op->get_precedence() > lhs_op.get_precedence(); op = peek_operator()) {
+ rhs = exec_expr(rhs, op->get_precedence());
+ }
+
+ lhs = lhs_op.exec(lhs, rhs);
+ }
+ return lhs;
+ }
+
+ std::optional<parser::BinaryOp> peek_operator() {
+ const auto token = m_lexer.peek_token();
+ if (!token.has_value() || !parser::BinaryOp::is(*token)) {
+ return {};
+ }
+ return parser::BinaryOp::from_token(*token);
+ }
+
+ double exec_primary() {
+ if (!m_lexer.has_token()) {
+ throw ParserError{"expected '-', '(' or a number"};
+ }
+
+ using Type = lexer::Token::Type;
+
+ if (m_lexer.drop_token_of_type(Type::MINUS).has_value()) {
+ return -exec_primary();
+ }
+
+ if (m_lexer.drop_token_of_type(Type::LEFT_PAREN).has_value()) {
+ const auto inner = exec_expr();
+ if (!m_lexer.has_token() || !m_lexer.drop_token_of_type(Type::RIGHT_PAREN).has_value()) {
+ throw ParserError{"missing closing ')'"};
+ }
+ return inner;
+ }
+
+ if (const auto token = m_lexer.drop_token_of_type(Type::NUMBER); token.has_value()) {
+ return token.value().as_number();
+ }
+
+ throw ParserError{"expected '-', '(' or a number"};
+ }
+
+ Lexer m_lexer;
+};
+
+}