common/sfio/sfnputc.c

	sfnputc.c revision 7c2fbfb345896881c631598ee3852ce9ce33fb07
/***********************************************************************
*                                                                      *
*               This software is part of the ast package               *
*          Copyright (c) 1985-2008 AT&T Intellectual Property          *
*                      and is licensed under the                       *
*                  Common Public License, Version 1.0                  *
*                    by AT&T Intellectual Property                     *
*                                                                      *
*                A copy of the License is available at                 *
*            http://www.opensource.org/licenses/cpl1.0.txt             *
*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
*                                                                      *
*              Information and Software Systems Research               *
*                            AT&T Research                             *
*                           Florham Park NJ                            *
*                                                                      *
*                 Glenn Fowler <gsf@research.att.com>                  *
*                  David Korn <dgk@research.att.com>                   *
*                   Phong Vo <kpv@research.att.com>                    *
*                                                                      *
***********************************************************************/
#include    "sfhdr.h"

/*  Write out a character n times
**
**  Written by Kiem-Phong Vo.
*/

#if __STD_C
ssize_t sfnputc(Sfio_t* f, int c, size_t n)
#else
ssize_t sfnputc(f,c,n)
Sfio_t*     f;  /* file to write */
int     c;  /* char to be written */
size_t      n;  /* number of time to repeat */
#endif
{
    reg uchar*  ps;
    reg ssize_t p, w;
    uchar       buf[128];
    reg int     local;
    SFMTXDECL(f);

    SFMTXENTER(f,-1);

    GETLOCAL(f,local);
    if(SFMODE(f,local) != SF_WRITE && _sfmode(f,SF_WRITE,local) < 0)
        SFMTXRETURN(f, -1);

    SFLOCK(f,local);

    /* write into a suitable buffer */
    if((size_t)(p = (f->endb-(ps = f->next))) < n)
        { ps = buf; p = sizeof(buf); }
    if((size_t)p > n)
        p = n;
    MEMSET(ps,c,p);
    ps -= p;

    w = n;
    if(ps == f->next)
    {   /* simple sfwrite */
        f->next += p;
        if(c == '\n')
            (void)SFFLSBUF(f,-1);
        goto done;
    }

    for(;;)
    {   /* hard write of data */
        if((p = SFWRITE(f,(Void_t*)ps,p)) <= 0 || (n -= p) <= 0)
        {   w -= n;
            goto done;
        }
        if((size_t)p > n)
            p = n;
    }
done :
    SFOPEN(f,local);
    SFMTXRETURN(f, w);
}