kolibrios/programs/develop/open watcom/trunk/clib/string/fstrchr.c

/****************************************************************************
*
*                            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
*    ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
*    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
*    NON-INFRINGEMENT. Please see the License for the specific language
*    governing rights and limitations under the License.
*
*  ========================================================================
*
* Description:  WHEN YOU FIGURE OUT WHAT THIS FILE DOES, PLEASE
*               DESCRIBE IT HERE!
*
****************************************************************************/


#include "variety.h"
#include <string.h>

#ifdef  M_I86

extern  char _WCFAR * _scan1( char _WCFAR *s, int c );

/* use scan1 to find the char we are looking for */

#pragma aux    _scan1 = 0x1e            /* push ds   */\
                        0x8e 0xda       /* mov ds,dx */\
                        0xad            /* L1:lodsw  */\
                        0x38 0xd8       /* cmp al,bl */\
                        0x74 0x22       /* je L3     */\
                        0x84 0xc0       /* test al,al*/\
                        0x74 0x19       /* je L2     */\
                        0x38 0xdc       /* cmp ah,bl */\
                        0x74 0x1b       /* je L4     */\
                        0x84 0xe4       /* test ah,ah*/\
                        0x74 0x11       /* je L2     */\
                        0xad            /* lodsw     */\
                        0x38 0xd8       /* cmp al,bl */\
                        0x74 0x11       /* je L3     */\
                        0x84 0xc0       /* test al,al*/\
                        0x74 0x08       /* je L2     */\
                        0x38 0xdc       /* cmp ah,bl */\
                        0x74 0x0a       /* je L4     */\
                        0x84 0xe4       /* test ah,ah*/\
                        0x75 0xde       /* jne L1    */\
                        0x31 0xf6       /* L2:xor si,si*/\
                        0x89 0xf2       /* mov dx,si */\
                        0xa9            /* test ax,... */\
                        0x4e            /* L3:dec si */\
                        0x4e            /* L4:dec si */\
                        0x1f            /* pop ds    */\
                        parm caller [dx si] [bl]\
                        value [dx si]\
                        modify [ax dx si];
#endif


/* locate the first occurrence of c in the initial n characters of the
   string pointed to by s. The terminating null character is considered
   to be part of the string.
   If the character c is not found, NULL is returned.
*/
#undef  _fstrchr

_WCRTLINK char _WCFAR *_fstrchr( const char _WCFAR *s, int c )
    {
//#if defined(M_I86)
        //return( _scan1( (char _WCFAR *)s, c ) );
//#else
        do {
            if( *s == c ) return( (char _WCFAR *)s );
        } while( *s++ != '\0' );
        return( NULL );
//#endif
    }