Generate items from grammar

10 files changed, 1020 insertions, 0 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
new file mode 100644
index 0000000..bb5e874
--- /dev/null
+++ b/src/CMakeLists.txt
@@ -0,0 +1,7 @@
+add_executable(solar
+  lex.cpp
+  parser.cpp
+  solar.cpp
+  state.cpp
+)
+set_target_properties(solar PROPERTIES COMPILE_FLAGS "-std=c++11 -Wall")
diff --git a/src/item.hpp b/src/item.hpp
new file mode 100644
index 0000000..58987b8
--- /dev/null
+++ b/src/item.hpp
@@ -0,0 +1,80 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+#include "symbol.hpp"
+
+#include <vector>
+
+
+namespace solar {
+
+struct item_t : public std::tuple<std::string, std::vector<symbol_t>, unsigned> {
+	item_t(const std::string &lhs)
+		: std::tuple<std::string, std::vector<symbol_t>, unsigned>(lhs, std::vector<symbol_t>(), 0) {}
+
+	const std::string & get_lhs() const {
+		return std::get<0>(*this);
+	}
+
+	std::string & get_lhs() {
+		return std::get<0>(*this);
+	}
+
+	const std::vector<symbol_t> & get_rhs() const {
+		return std::get<1>(*this);
+	}
+
+	std::vector<symbol_t> & get_rhs() {
+		return std::get<1>(*this);
+	}
+
+	unsigned get_point() const {
+		return std::get<2>(*this);
+	}
+
+	unsigned & get_point() {
+		return std::get<2>(*this);
+	}
+
+	bool can_shift() const {
+		return get_point() < get_rhs().size();
+	}
+
+	void shift() {
+		get_point()++;
+	}
+
+	symbol_t get_next_symbol() const {
+		if (can_shift())
+			return get_rhs()[get_point()];
+		else
+			return symbol_t::make_end();
+	}
+};
+
+}
diff --git a/src/lex.cpp b/src/lex.cpp
new file mode 100644
index 0000000..0587689
--- /dev/null
+++ b/src/lex.cpp
@@ -0,0 +1,369 @@
+/*
+  Copyright (c) 2013-2014, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "lex.hpp"
+
+#include <cstdlib>
+
+
+#define array_size(array) (sizeof(array)/sizeof((array)[0]))
+
+
+namespace solar {
+
+
+struct keyword_t {
+	const char *keyword;
+	int token;
+};
+
+/* the keyword list must be sorted */
+static const keyword_t keywords[] = {
+};
+
+static int compare_keywords(const void *v1, const void *v2) {
+	const keyword_t *k1 = static_cast<const keyword_t*>(v1), *k2 = static_cast<const keyword_t*>(v2);
+	return std::strcmp(k1->keyword, k2->keyword);
+}
+
+
+bool lex_t::advance() {
+	if (start > 0) {
+		std::memmove(buffer, buffer+start, end - start);
+		end -= start;
+		start = 0;
+	}
+
+	if (end == sizeof(buffer))
+		return false;
+
+	size_t l = std::fread(buffer+end, 1, sizeof(buffer) - end, file);
+
+	end += l;
+	return l;
+}
+
+bool lex_t::next(bool move) {
+	if (start + tok_len >= end)
+		return false;
+
+	if (current() == '\n') {
+		loc.last_column = 0;
+		loc.last_line++;
+	}
+	else {
+		loc.last_column++;
+	}
+
+	if (move)
+		start++;
+	else
+		tok_len++;
+
+
+	if (start + tok_len >= end)
+		return advance();
+
+	return true;
+}
+
+void lex_t::consume(bool consume_needspace) {
+	start += tok_len;
+	tok_len = 0;
+
+	needspace = consume_needspace;
+}
+
+int lex_t::io_error(value_t *value) {
+	value->error = "I/O error";
+	return -1;
+}
+
+int lex_t::syntax_error(value_t *value) {
+	if (std::ferror(file))
+		return io_error(value);
+
+	value->error = "syntax error";
+	return -1;
+}
+
+int lex_t::consume_comment(value_t *value) {
+	char prev = 0;
+
+	while (next(true)) {
+		if (prev == '*' && current() == '/') {
+			next(true);
+			consume(false);
+			return 0;
+		}
+
+		prev = current();
+	}
+
+	if (std::ferror(file))
+		return io_error(value);
+
+	value->error = "unterminated block comment";
+	return -1;
+}
+
+/*
+int lex_t::unterminated_string(value_t *value) {
+	if (ferror(file))
+		return io_error(value);
+
+	value->error = "unterminated string";
+	return -1;
+}
+
+int lex_t::lex_string(value_t *value) {
+	char *buf = NULL;
+	size_t len = 1024;
+	size_t pos = 0;
+
+	if (needspace)
+		return syntax_error(value);
+
+	buf = static_cast<char*>(std::malloc(len));
+
+	while (true) {
+		if (!next(true)) {
+			std::free(buf);
+			return unterminated_string(value);
+		}
+
+		char cur = current();
+
+		if (cur == '"')
+			break;
+
+		if (cur == '\\') {
+			if (!next(true)) {
+				free(buf);
+				return unterminated_string(value);
+			}
+
+			cur = current();
+
+			if (cur == '\n')
+				continue;
+		}
+
+		if (pos >= len) {
+			len *= 2;
+			buf = static_cast<char*>(std::realloc(buf, len));
+		}
+
+		buf[pos++] = cur;
+	}
+
+	value->str = strndup(buf, pos);
+	std::free(buf);
+
+	next(true);
+	consume(true);
+
+	return TOK_STRING;
+	}*/
+
+int lex_t::lex_number(value_t *value) {
+	if (needspace)
+		return syntax_error(value);
+
+	while (next(false)) {
+		char cur = current();
+
+		if (cur >= '0' && cur <= '9')
+			continue;
+
+		if (cur == 'x' || (cur >= 'a' && cur <= 'f') || (cur >= 'A' && cur <= 'F'))
+			continue;
+
+		break;
+	}
+
+	char *endptr, *token = get_token();
+	value->number = std::strtoull(token, &endptr, 0);
+
+	bool ok = !*endptr;
+	free(token);
+
+	if (!ok)
+		return syntax_error(value);
+
+	consume(true);
+
+	return TOK_UINT;
+}
+
+int lex_t::lex_keyword(value_t *value) {
+	if (needspace)
+		return syntax_error(value);
+
+	while (next(false)) {
+		char cur = current();
+
+		if (!((cur >= 'a' && cur <= 'z') || (cur >= '0' && cur <= '9') || cur == '-'))
+			break;
+	}
+
+	char *token = get_token();
+	const keyword_t key = { .keyword = token, .token = 0 };
+	const keyword_t *ret = static_cast<const keyword_t*>(bsearch(&key, keywords, array_size(keywords), sizeof(keyword_t), compare_keywords));
+	free(token);
+
+	if (!ret)
+		return syntax_error(value);
+
+	consume(true);
+
+	return ret->token;
+}
+
+int lex_t::lex_symbol(value_t *value, bool terminal) {
+	if (needspace)
+		return syntax_error(value);
+
+	while (next(false)) {
+		char cur = current();
+
+		switch (cur) {
+		case 'A' ... 'Z':
+			if (!terminal)
+				break;
+
+			continue;
+
+		case 'a' ... 'z':
+			if (terminal)
+				break;
+
+			continue;
+
+		case '0' ... '9':
+		case '_':
+			continue;
+		}
+
+		break;
+	}
+
+	value->str = get_token();
+	return terminal ? TOK_TERM : TOK_NONTERM;
+}
+
+int lex_t::lex(value_t *value) {
+	int token;
+
+	while (end > start) {
+		loc.first_line = loc.last_line;
+		loc.first_column = loc.last_column+1;
+
+		switch (current()) {
+		case ' ':
+		case '\n':
+		case '\t':
+		case '\r':
+			next(true);
+			consume(false);
+			continue;
+
+		case ';':
+		case ':':
+		case '{':
+		case '}':
+		case '|':
+		case '=':
+			token = current();
+			next(true);
+			consume(false);
+			return token;
+
+		case '/':
+			if (!next(true))
+				return syntax_error(value);
+
+			if (current() == '*') {
+				token = consume_comment(value);
+				if (token)
+					return token;
+
+				continue;
+			}
+
+			if (current() != '/')
+				return syntax_error(value);
+
+			///* fall-through */
+			//case '#':
+			while (next(true)) {
+				if (current() == '\n')
+					break;
+			}
+
+			next(true);
+			consume(false);
+			continue;
+
+		case '\'':
+			if (!next(true))
+				return syntax_error(value);
+
+			value->number = current();
+
+			if (!next(true) || current() != '\'')
+				return syntax_error(value);
+
+			next(true);
+
+			consume(false);
+
+			return TOK_CHAR;
+
+			//case '"':
+			//return lex_string(value);
+
+		case '0' ... '9':
+			return lex_number(value);
+
+		case 'a' ... 'z':
+			return lex_symbol(value, false);
+
+		case 'A' ... 'Z':
+			return lex_symbol(value, true);
+
+		default:
+			return syntax_error(value);
+		}
+	}
+
+	if (ferror(file))
+		return io_error(value);
+
+	return 0;
+}
+
+}
diff --git a/src/lex.hpp b/src/lex.hpp
new file mode 100644
index 0000000..8898d0b
--- /dev/null
+++ b/src/lex.hpp
@@ -0,0 +1,102 @@
+/*
+  Copyright (c) 2013-2014, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+#include "parser.hpp"
+
+#include <cstdio>
+#include <cstring>
+
+
+namespace solar {
+
+struct location_t {
+public:
+	int first_line;
+	int first_column;
+	int last_line;
+	int last_column;
+
+	location_t() : first_line(1), first_column(0), last_line(1), last_column(0) {}
+};
+
+class lex_t {
+private:
+	location_t loc;
+
+	std::FILE *file;
+
+	bool needspace;
+
+	size_t start;
+	size_t end;
+	size_t tok_len;
+	char buffer[65556];
+
+
+	bool advance();
+	bool next(bool move);
+	void consume(bool needspace);
+
+	int io_error(value_t *value);
+	int syntax_error(value_t *value);
+	int consume_comment(value_t *value);
+	//int unterminated_string(value_t *value);
+
+	int lex_string(value_t *value);
+	int lex_address(value_t *value);
+	int lex_float(value_t *value);
+	int lex_number(value_t *value);
+	int lex_keyword(value_t *value);
+	int lex_symbol(value_t *value, bool terminal);
+
+	char current() {
+		return buffer[start + tok_len];
+	}
+
+	char * get_token() {
+		return strndup(buffer+start, tok_len);
+	}
+
+
+public:
+	lex_t(FILE *file0) : file(file0), needspace(false), start(0), end(0), tok_len(0) {
+		advance();
+	}
+
+	~lex_t() {
+		fclose(file);
+	}
+
+	int lex(value_t *value);
+
+	const location_t & get_location() const {
+		return loc;
+	}
+};
+
+}
diff --git a/src/parser.cpp b/src/parser.cpp
new file mode 100644
index 0000000..bd4dfbf
--- /dev/null
+++ b/src/parser.cpp
@@ -0,0 +1,125 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "parser.hpp"
+
+#include <cstdlib>
+
+
+namespace solar {
+
+enum parser_state {
+	STATE_INIT,
+	STATE_RULE_BAR,
+	STATE_RULE_EQUAL,
+	STATE_RULE,
+};
+
+struct parser {
+	parser_state state;
+};
+
+parser_t * parser_alloc(void) {
+	parser_t *parser = (parser_t *)std::malloc(sizeof(parser_t));
+	parser->state = STATE_INIT;
+
+	return parser;
+}
+
+int parser_push(parser_t *parser, int token, const value_t *value, state_t *state) {
+	switch (parser->state) {
+	case STATE_INIT:
+		switch (token) {
+		case TOK_NONTERM:
+			parser->state = STATE_RULE_BAR;
+			state->new_rule(value->str);
+			free(value->str);
+			return 1;
+
+		case 0:
+			return 0;
+		}
+
+		break;
+
+	case STATE_RULE_BAR:
+		if (token == '|') {
+			parser->state = STATE_RULE_EQUAL;
+			return 1;
+		}
+
+		break;
+
+	case STATE_RULE_EQUAL:
+		if (token == '=') {
+			parser->state = STATE_RULE;
+			return 1;
+		}
+
+		break;
+
+	case STATE_RULE:
+		switch (token) {
+		case TOK_NONTERM:
+			state->add_rule_nonterminal(value->str);
+			free(value->str);
+			return 1;
+
+		case TOK_TERM:
+			state->add_rule_terminal(value->str);
+			free(value->str);
+			return 1;
+
+		case TOK_CHAR:
+			state->add_rule_terminal(value->number);
+			return 1;
+
+		case TOK_BLOCK:
+		case ';':
+			state->add_rule();
+			parser->state = STATE_INIT;
+			return 1;
+		}
+
+		break;
+	}
+
+	switch (token) {
+	case TOK_NONTERM:
+	case TOK_TERM:
+	case TOK_CHAR:
+	case TOK_BLOCK:
+		free(value->str);;
+	}
+
+	return -1;
+}
+
+void parser_free(parser_t *parser) {
+	std::free(parser);
+}
+
+}
diff --git a/src/parser.hpp b/src/parser.hpp
new file mode 100644
index 0000000..c5a1e48
--- /dev/null
+++ b/src/parser.hpp
@@ -0,0 +1,58 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+#include "state.hpp"
+
+#include <cstdint>
+
+
+namespace solar {
+
+enum token_t {
+	TOK_TERM = 1,
+	TOK_NONTERM,
+	TOK_BLOCK,
+	TOK_CHAR,
+	TOK_UINT,
+};
+
+typedef struct value {
+	char *str;
+	uint64_t number;
+	const char *error;
+} value_t;
+
+
+typedef struct parser parser_t;
+
+
+parser_t * parser_alloc(void);
+int parser_push(parser_t *parser, int token, const value_t *value, state_t *state);
+void parser_free(parser_t *parser);
+
+}
diff --git a/src/solar.cpp b/src/solar.cpp
new file mode 100644
index 0000000..a5085a1
--- /dev/null
+++ b/src/solar.cpp
@@ -0,0 +1,83 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "lex.hpp"
+#include "parser.hpp"
+
+#include <cstdio>
+#include <memory>
+
+
+namespace solar {
+
+bool read_grammar(const char *filename, state_t *state) {
+	FILE *file = fopen(filename, "r");
+	if (!file) {
+		std::fprintf(stderr, "unable to open file %s\n", filename);
+		return false;
+	}
+
+	std::unique_ptr<lex_t> lexer(new lex_t(file));
+	parser_t *parser = parser_alloc();
+	int ret;
+
+	do {
+		int token;
+		value_t value;
+
+		token = lexer->lex(&value);
+		if (token < 0) {
+			std::fprintf(stderr, "error: %s at %s:%i:%i\n", value.error, filename,
+				     lexer->get_location().first_line, lexer->get_location().first_column);
+			return false;
+		}
+
+		ret = parser_push(parser, token, &value, state);
+	} while (ret > 0);
+
+	if (ret < 0) {
+		std::fprintf(stderr, "error: parse error at %s:%i:%i\n", filename,
+			     lexer->get_location().first_line, lexer->get_location().first_column);
+		return false;
+	}
+
+	parser_free(parser);
+
+	return true;
+}
+
+}
+
+
+int main() {
+	using namespace solar;
+
+	state_t state;
+	if (!read_grammar("grammar.y", &state))
+		return 1;
+
+	return 0;
+}
diff --git a/src/state.cpp b/src/state.cpp
new file mode 100644
index 0000000..e798dce
--- /dev/null
+++ b/src/state.cpp
@@ -0,0 +1,67 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "state.hpp"
+
+
+namespace solar {
+
+void state_t::new_rule(const char *nonterm) {
+	if (rules.empty()) {
+		// start rule
+		current.get_rhs().emplace_back(symbol_t::make_nonterm(nonterm));
+		add_rule();
+	}
+
+	current = item_t(nonterm);
+
+}
+
+void state_t::add_rule_nonterminal(const char *nonterm) {
+	current.get_rhs().emplace_back(symbol_t::make_nonterm(nonterm));
+}
+
+void state_t::add_rule_terminal(const char *term) {
+	current.get_rhs().emplace_back(symbol_t::make_term(term));
+}
+
+void state_t::add_rule_terminal(unsigned char term) {
+	current.get_rhs().emplace_back(symbol_t::make_char(term));
+}
+
+void state_t::add_rule() {
+	rules.emplace(current.get_lhs(), current);
+
+	while (true) {
+		items.emplace(current.get_next_symbol(), current);
+		if (!current.can_shift())
+			break;
+
+		current.shift();
+	}
+}
+
+}
diff --git a/src/state.hpp b/src/state.hpp
new file mode 100644
index 0000000..8069ef0
--- /dev/null
+++ b/src/state.hpp
@@ -0,0 +1,58 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+#include "item.hpp"
+
+#include <map>
+#include <utility>
+
+
+namespace solar {
+
+class state_t {
+private:
+	std::multimap<std::string, item_t> rules;
+	std::multimap<symbol_t, item_t> items;
+
+	item_t current;
+
+public:
+	state_t() : current("") {}
+
+	const std::multimap<std::string, item_t> & get_rules() const {
+		return rules;
+	}
+
+	void new_rule(const char *nonterm);
+	void add_rule_nonterminal(const char *nonterm);
+	void add_rule_terminal(const char *term);
+	void add_rule_terminal(unsigned char term);
+	void add_rule();
+};
+
+}
diff --git a/src/symbol.hpp b/src/symbol.hpp
new file mode 100644
index 0000000..31b006d
--- /dev/null
+++ b/src/symbol.hpp
@@ -0,0 +1,71 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+#include <string>
+#include <tuple>
+
+
+namespace solar {
+
+enum symbol_type_t {
+	SYMBOL_TYPE_END,
+	SYMBOL_TYPE_NONTERM,
+	SYMBOL_TYPE_TERM,
+	SYMBOL_TYPE_CHAR,
+};
+
+struct symbol_t : public std::tuple<symbol_type_t, std::string>  {
+	symbol_t(symbol_type_t type, const char *value) : std::tuple<symbol_type_t, std::string>(type, value) {}
+
+	symbol_type_t get_type() const {
+		return std::get<0>(*this);
+	}
+
+	const std::string & get_value() const {
+		return std::get<1>(*this);
+	}
+
+	static symbol_t make_end() {
+		return symbol_t(SYMBOL_TYPE_END, "");
+	}
+
+	static symbol_t make_nonterm(const char *value) {
+		return symbol_t(SYMBOL_TYPE_NONTERM, value);
+	}
+
+	static symbol_t make_term(const char *value) {
+		return symbol_t(SYMBOL_TYPE_TERM, value);
+	}
+
+	static symbol_t make_char(unsigned char value) {
+		char v[2] = {char(value), 0};
+		return symbol_t(SYMBOL_TYPE_CHAR, v);
+	}
+};
+
+}