cde/programs/dtksh/ksh93/src/lib/libast/sfio/sfflsbuf.c

   1 /*
   2  * CDE - Common Desktop Environment
   3  *
   4  * Copyright (c) 1993-2012, The Open Group. All rights reserved.
   5  *
   6  * These libraries and programs are free software; you can
   7  * redistribute them and/or modify them under the terms of the GNU
   8  * Lesser General Public License as published by the Free Software
   9  * Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  * These libraries and programs are distributed in the hope that
  13  * they will be useful, but WITHOUT ANY WARRANTY; without even the
  14  * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  15  * PURPOSE. See the GNU Lesser General Public License for more
  16  * details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with these librararies and programs; if not, write
  20  * to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
  21  * Floor, Boston, MA 02110-1301 USA
  22  */
  23 /* $XConsortium: sfflsbuf.c /main/3 1995/11/01 18:29:15 rswiston $ */
  24 /***************************************************************
  25 *                                                              *
  26 *                      AT&T - PROPRIETARY                      *
  27 *                                                              *
  28 *         THIS IS PROPRIETARY SOURCE CODE LICENSED BY          *
  29 *                          AT&T CORP.                          *
  30 *                                                              *
  31 *                Copyright (c) 1995 AT&T Corp.                 *
  32 *                     All Rights Reserved                      *
  33 *                                                              *
  34 *           This software is licensed by AT&T Corp.            *
  35 *       under the terms and conditions of the license in       *
  36 *       http://www.research.att.com/orgs/ssr/book/reuse        *
  37 *                                                              *
  38 *               This software was created by the               *
  39 *           Software Engineering Research Department           *
  40 *                    AT&T Bell Laboratories                    *
  41 *                                                              *
  42 *               For further information contact                *
  43 *                     gsf@research.att.com                     *
  44 *                                                              *
  45 ***************************************************************/
  46 #include        "sfhdr.h"
  47
  48 /*      Write a buffer out to a file descriptor or
  49 **      extending a buffer for a SF_STRING stream.
  50 **
  51 **      Written by Kiem-Phong Vo (06/27/90)
  52 */
  53
  54 #if __STD_C
  55 _sfflsbuf(reg Sfio_t* f, reg int c)
  56 #else
  57 _sfflsbuf(f,c)
  58 reg Sfio_t      *f;     /* write out the buffered content of this stream */
  59 reg int         c;      /* if c>=0, c is also written out */
  60 #endif
  61 {
  62         reg int         n, w;
  63         reg uchar       *data;
  64         uchar           outc;
  65         reg int         local;
  66         int             inpc = c;
  67
  68         GETLOCAL(f,local);
  69
  70         for(;; f->mode &= ~SF_LOCK)
  71         {       /* check stream mode */
  72                 if(SFMODE(f,local) != SF_WRITE && _sfmode(f,SF_WRITE,local) < 0)
  73                         return -1;
  74                 SFLOCK(f,local);
  75
  76                 /* current data extent */
  77                 n = f->next - (data = f->data);
  78
  79                 if(n == (f->endb-f->data) && (f->flags&SF_STRING))
  80                 {       /* extend string stream buffer */
  81                         (void)SFWR(f,data,1,f->disc);
  82
  83                         /* !(f->flags&SF_STRING) is required because exception
  84                            handlers may turn a string stream to a file stream */
  85                         if(f->next < f->endb || !(f->flags&SF_STRING) )
  86                                 n = f->next - (data = f->data);
  87                         else
  88                         {       SFOPEN(f,local);
  89                                 return -1;
  90                         }
  91                 }
  92
  93                 if(c >= 0)
  94                 {       /* write into buffer */
  95                         if(n < (f->endb - (data = f->data)))
  96                         {       *f->next++ = c;
  97                                 if(c != '\n' ||
  98                                    !(f->flags&SF_LINE) || (f->flags&SF_STRING))
  99                                         break;
 100                                 c = -1;
 101                                 n += 1;
 102                         }
 103                         else if(n == 0)
 104                         {       /* unbuffered io */
 105                                 outc = (uchar)c;
 106                                 data = &outc;
 107                                 c = -1;
 108                                 n = 1;
 109                         }
 110                 }
 111
 112                 /* writing data */
 113                 if(n == 0 || (f->flags&SF_STRING))
 114                         break;
 115                 else if((w = SFWR(f,data,n,f->disc)) > 0)
 116                 {       if((n -= w) > 0) /* save unwritten data, then resume */
 117                                 memcpy((char*)f->data,(char*)data+w,n);
 118                         f->next = f->data+n;
 119                         if(n == 0 && c < 0)
 120                                 break;
 121                 }
 122                 else if(w == 0)
 123                 {       SFOPEN(f,local);
 124                         return -1;
 125                 }
 126                 else if(c < 0)
 127                         break;
 128         }
 129
 130         SFOPEN(f,local);
 131         return inpc < 0 ? (f->endb-f->next) : inpc;
 132 }