/*
 * TRConfig.m vi:ts=4:sw=4:expandtab:
 * Generic Configuration Parser
 *
 * Author: Landon Fuller <landonf@threerings.net>
 *
 * Copyright (c) 2006 - 2007 Three Rings Design, Inc.
 * 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.
 * 3. Neither the name of the copyright holder nor the names of any 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 OWNER 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.
 */

#ifdef HAVE_CONFIG_H
#import <config.h>
#endif

#import <stdlib.h>

#import "TRConfig.h"
#import "TRConfigLexer.h"
#import "TRConfigParser.h"
#import "TRConfigToken.h"

/**
 * An Apache-style configuration file parser/lexer.
 */
@implementation TRConfig

/**
 * Initialize and return a TRConfig parser.
 * @param fd A file descriptor open for reading. This file descriptor will be
 *         mmap()ed, and thus must reference a file.
 * @param delegate A configuration delegate conforming to the TRConfigDelegate protocol.
 */
- (id) initWithFD: (int) fd configDelegate: (id <TRConfigDelegate>) delegate {
    self = [self init];

    if (self) {
        _fd = fd;
        _delegate = delegate;
        _error = NO;
    }

    return self;
}

/**
 * Parse the configuration file
 * @result true on success, false on failure.
 */
- (BOOL) parseConfig {
    TRConfigLexer *lexer = NULL;
    TRConfigToken *token;
    void *parser;

    /* Initialize our lexer */
    lexer = [[TRConfigLexer alloc] initWithFD: _fd];
    if (lexer == NULL)
        return false;

    /* Initialize the parser */
    parser = TRConfigParseAlloc(malloc);

    /* Scan in tokens and hand them off to the parser */
    while ((token = [lexer scan]) != NULL) {
        TRConfigParse(parser, [token tokenID], token, _delegate);
        /* If we've been asked to stop, do so */
        if (_error)
            break;
    }
    /* Signal EOF and clean up */
    if (!_error) {
        /* Only trigger EOF handling if no errors occured */
        TRConfigParse(parser, 0, NULL, _delegate);
    }
    TRConfigParseFree(parser, free);
    [lexer release];

    /* Did an error occur? */
    if (_error)
        return false;

    return true;
}

/* Re-entrant callback used to signal an error by the parser delegate, called
 * from within the bowels of TRConfigParse() */
- (void) errorStop {
    _error = YES;
}

@end
