opcostch.cpp

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C++ 代码 · 共 93 行

/****************************************************************************
*
*                            Open Watcom Project
*
*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
*  ========================================================================
*
*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
*    Public License version 1.0 (the 'License'). You may not use this file
*    except in compliance with the License. BY USING THIS FILE YOU AGREE TO
*    ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
*    provided with the Original Code and Modifications, and is also
*    available at www.sybase.com/developer/opensource.
*
*    The Original Code and all software distributed under the License are
*    distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
*    EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
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*    NON-INFRINGEMENT. Please see the License for the specific language
*    governing rights and limitations under the License.
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*  ========================================================================
*
* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
*               DESCRIBE IT HERE!
*
****************************************************************************/


// %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
// %     Copyright (C) 1992, by WATCOM International Inc.  All rights    %
// %     reserved.  No part of this software may be reproduced or        %
// %     used in any form or by any means - graphic, electronic or       %
// %     mechanical, including photocopying, recording, taping or        %
// %     information storage and retrieval systems - except with the     %
// %     written permission of WATCOM International Inc.                 %
// %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//
//  Modified    By              Reason
//  ========    ==              ======
//  92/01/09    Steve McDowell  Initial simple implementation using C library
//                              string functions wherever possible.
//  92/01/20    ...             Added checking for invalid Strings, including
//                              adding the ! operator, the == and !=
//                              operators with integer arguments, and the
//                              "valid" member and friend functions.
//  92/03/11    ...             Re-implemented using StringReps (reference
//                              counts, offset and length).
//  92/10/08    Greg Bentz      Cleanup.
//  93/08/31    Greg Bentz      - make extractor skip whitespace if
//                                ios::skipws is set
//                              - correct offset computation in substring
//  93/10/07    Greg Bentz      - alloc_mult_size() not setting new value right
//  93/10/19    Raymond Tang    split into separate files
//  94/04/06    Greg Bentz      combine header files

#include "strng.h"
#include "stghdr.h"

String::operator const char *() {
/*******************************/
// Conversion operator: convert a String to a (const char *)
// NOTE: the pointer returned is valid only as long as "this" is valid.
//       If the C string should persist longer, then it should be copied
//       (eg. using strdup)

    ::free( __c_string );
#ifndef NDEBUG
    if( __c_string != NULL ) {
        _CStrAllocCount--;
    }
#endif
    if( __srep == NULL ) {
        __c_string = NULL;
        return( __c_string );
    }
    __c_string = (char *) ::malloc( __slength + 1 );
    if( __c_string == NULL ) {
        return( __c_string );
    }
#ifndef NDEBUG
    _CStrAllocCount++;
#endif
    if( __slength > 0 ) {
        ::memcpy( __c_string, __srep->__value + __offset, __slength );
    }
    __c_string[__slength] = '\0';
    return( __c_string );
}