usr/src/lib/libast/common/disc/sfdcslow.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #include "sfdchdr.h"
  23
  24 /*      Make a stream op return immediately on interrupts.
  25 **      This is useful on slow streams (hence the name).
  26 **
  27 **      Written by Glenn Fowler (03/18/1998).
  28 */
  29
  30 #if __STD_C
  31 static int slowexcept(Sfio_t* f, int type, Void_t* v, Sfdisc_t* disc)
  32 #else
  33 static int slowexcept(f, type, v, disc)
  34 Sfio_t*         f;
  35 int             type;
  36 Void_t*         v;
  37 Sfdisc_t*       disc;
  38 #endif
  39 {
  40         NOTUSED(f);
  41         NOTUSED(v);
  42         NOTUSED(disc);
  43
  44         switch (type)
  45         {
  46         case SF_FINAL:
  47         case SF_DPOP:
  48                 free(disc);
  49                 break;
  50         case SF_READ:
  51         case SF_WRITE:
  52                 if (errno == EINTR)
  53                         return(-1);
  54                 break;
  55         }
  56
  57         return(0);
  58 }
  59
  60 #if __STD_C
  61 int sfdcslow(Sfio_t* f)
  62 #else
  63 int sfdcslow(f)
  64 Sfio_t* f;
  65 #endif
  66 {
  67         Sfdisc_t*       disc;
  68
  69         if(!(disc = (Sfdisc_t*)malloc(sizeof(Sfdisc_t))) )
  70                 return(-1);
  71
  72         disc->readf = NIL(Sfread_f);
  73         disc->writef = NIL(Sfwrite_f);
  74         disc->seekf = NIL(Sfseek_f);
  75         disc->exceptf = slowexcept;
  76
  77         if(sfdisc(f,disc) != disc)
  78         {       free(disc);
  79                 return(-1);
  80         }
  81
  82         return(0);
  83 }