From 966fe28c59f59fc8be795c8215b9352435982445 Mon Sep 17 00:00:00 2001 From: Aki Date: Thu, 30 Sep 2021 16:46:36 +0200 Subject: Merged nGenEx and Parser into Stars45 --- Stars45/Parser.cpp | 333 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 333 insertions(+) create mode 100644 Stars45/Parser.cpp (limited to 'Stars45/Parser.cpp') diff --git a/Stars45/Parser.cpp b/Stars45/Parser.cpp new file mode 100644 index 0000000..4a84841 --- /dev/null +++ b/Stars45/Parser.cpp @@ -0,0 +1,333 @@ +/* Starshatter OpenSource Distribution + Copyright (c) 1997-2004, Destroyer Studios LLC. + All Rights Reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + * Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + * 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. + * Neither the name "Destroyer Studios" nor the names of its contributors + may be used to endorse or promote products derived from this software + without specific prior written permission. + + 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. + + SUBSYSTEM: Parser + FILE: Parser.cpp + AUTHOR: John DiCamillo + + + OVERVIEW + ======== + Implementation of the generic Parser class +*/ + +#include "MemDebug.h" +#include "reader.h" +#include "token.h" +#include "parser.h" +#include +#include + +enum KEYS { KEY_TRUE, KEY_FALSE, KEY_DEF, KEY_MINUS }; + +void Print(const char* fmt, ...); + +static int dump_tokens = 0; + +// +-------------------------------------------------------------------+ + +Term* error(char* msg, const Token& token) +{ + static char buf[1024]; + sprintf_s(buf, " near '%s' in line %d.", (const char*) token.symbol(), token.line()); + + return error(msg, buf); +} + +// +-------------------------------------------------------------------+ + +Parser::Parser(Reader* r) +{ + reader = r ? r : new(__FILE__, __LINE__) ConsoleReader; + lexer = new(__FILE__, __LINE__) Scanner(reader); + + Token::addKey("true", KEY_TRUE); + Token::addKey("false", KEY_FALSE); + Token::addKey(":", KEY_DEF); + Token::addKey("-", KEY_MINUS); +} + +Parser::~Parser() +{ + delete lexer; + delete reader; + //Token::close(); +} + +Term* +Parser::ParseTerm() +{ + Term* t = ParseTermBase(); + if (t == 0) return t; + + Term* t2 = ParseTermRest(t); + + return t2; +} + +Term* +Parser::ParseTermRest(Term* base) +{ + Token t = lexer->Get(); + + switch (t.type()) { + default: + lexer->PutBack(); + return base; + + case Token::StringLiteral: { + // concatenate adjacent string literal tokens: + TermText* text = base->isText(); + if (text) { + TermText* base2 = new(__FILE__, __LINE__) TermText(text->value() + t.symbol()(1, t.symbol().length()-2)); + delete base; + return ParseTermRest(base2); + } + else { + lexer->PutBack(); + } + } + break; + + case Token::Keyword: + switch (t.key()) { + case KEY_DEF: + if (base->isText()) + return new(__FILE__, __LINE__) TermDef(base->isText(), ParseTerm()); + else + return error("(Parse) illegal lhs in def", t); + + default: + lexer->PutBack(); + return base; + } + break; + } + + return base; +} + +static int xtol(const char* p) +{ + int n = 0; + + while (*p) { + char digit = *p++; + n *= 16; + + if (digit >= '0' && digit <= '9') + n += digit - '0'; + + else if (digit >= 'a' && digit <= 'f') + n += digit - 'a' + 10; + + else if (digit >= 'A' && digit <= 'F') + n += digit - 'A' + 10; + } + + return n; +} + +Term* +Parser::ParseTermBase() +{ + Token t = lexer->Get(); + int n = 0; + double d = 0.0; + + switch (t.type()) { + case Token::IntLiteral: { + if (dump_tokens) + Print("%s", t.symbol().data()); + + char nstr[256], *p = nstr; + for (int i = 0; i < (int) t.symbol().length(); i++) + if (t.symbol()[i] != '_') + *p++ = t.symbol()[i]; + *p++ = '\0'; + + // handle hex notation: + if (nstr[1] == 'x') + n = xtol(nstr+2); + + else + n = atol(nstr); + + return new(__FILE__, __LINE__) TermNumber(n); + } + + case Token::FloatLiteral: { + if (dump_tokens) + Print("%s", t.symbol().data()); + + char nstr[256], *p = nstr; + for (int i = 0; i < (int) t.symbol().length(); i++) + if (t.symbol()[i] != '_') + *p++ = t.symbol()[i]; + *p++ = '\0'; + + d = atof(nstr); + return new(__FILE__, __LINE__) TermNumber(d); + } + + case Token::StringLiteral: + if (dump_tokens) + Print("%s", t.symbol().data()); + + return new(__FILE__, __LINE__) TermText(t.symbol()(1, t.symbol().length()-2)); + + case Token::AlphaIdent: + if (dump_tokens) + Print("%s", t.symbol().data()); + + return new(__FILE__, __LINE__) TermText(t.symbol()); + + case Token::Keyword: + if (dump_tokens) + Print("%s", t.symbol().data()); + + switch (t.key()) { + case KEY_FALSE: return new(__FILE__, __LINE__) TermBool(0); + case KEY_TRUE: return new(__FILE__, __LINE__) TermBool(1); + + case KEY_MINUS: { + Token next = lexer->Get(); + if (next.type() == Token::IntLiteral) { + if (dump_tokens) + Print("%s", next.symbol().data()); + + char nstr[256], *p = nstr; + for (int i = 0; i < (int) next.symbol().length(); i++) + if (next.symbol()[i] != '_') + *p++ = next.symbol()[i]; + *p++ = '\0'; + + n = -1 * atol(nstr); + return new(__FILE__, __LINE__) TermNumber(n); + } + else if (next.type() == Token::FloatLiteral) { + if (dump_tokens) + Print("%s", next.symbol().data()); + + char nstr[256], *p = nstr; + for (int i = 0; i < (int) next.symbol().length(); i++) + if (next.symbol()[i] != '_') + *p++ = next.symbol()[i]; + *p++ = '\0'; + + d = -1.0 * atof(nstr); + return new(__FILE__, __LINE__) TermNumber(d); + } + else { + lexer->PutBack(); + return error("(Parse) illegal token '-': number expected", next); + } + } + break; + + default: + lexer->PutBack(); + return 0; + } + + case Token::LParen: return ParseArray(); + + case Token::LBrace: return ParseStruct(); + + case Token::CharLiteral: + return error("(Parse) illegal token ", t); + + default: + lexer->PutBack(); + return 0; + } +} + +TermArray* +Parser::ParseArray() +{ + TermList* elems = ParseTermList(0); + Token end = lexer->Get(); + + if (end.type() != Token::RParen) + return (TermArray*) error("(Parse) ')' missing in array-decl", end); + + return new(__FILE__, __LINE__) TermArray(elems); +} + +TermStruct* +Parser::ParseStruct() +{ + TermList* elems = ParseTermList(1); + Token end = lexer->Get(); + + if (end.type() != Token::RBrace) + return (TermStruct*) error("(Parse) '}' missing in struct", end); + + return new(__FILE__, __LINE__) TermStruct(elems); +} + +TermList* +Parser::ParseTermList(int for_struct) +{ + TermList* tlist = new(__FILE__, __LINE__) TermList; + + Term* term = ParseTerm(); + while (term) { + if (for_struct && !term->isDef()) { + return (TermList*) error("(Parse) non-definition term in struct"); + } + else if (!for_struct && term->isDef()) { + return (TermList*) error("(Parse) illegal definition in array"); + } + + tlist->append(term); + Token t = lexer->Get(); + + /*** OLD WAY: COMMA SEPARATORS REQUIRED *** + if (t.type() != Token::Comma) { + lexer->PutBack(); + term = 0; + } + else + term = ParseTerm(); + /*******************************************/ + + // NEW WAY: COMMA SEPARATORS OPTIONAL: + if (t.type() != Token::Comma) { + lexer->PutBack(); + } + + term = ParseTerm(); + } + + return tlist; +} + + + -- cgit v1.1