libguile/vports.c

   1 /*      Copyright (C) 1995,1996,1998,1999 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41 \f
  42
  43 #include <stdio.h>
  44 #include "_scm.h"
  45 #include "eval.h"
  46 #include "chars.h"
  47 #include "fports.h"
  48
  49 #include "vports.h"
  50
  51 #ifdef HAVE_STRING_H
  52 #include <string.h>
  53 #endif
  54
  55 \f
  56
  57 /* {Ports - soft ports}
  58  *
  59  */
  60
  61
  62 static void
  63 sf_flush (SCM port)
  64 {
  65   scm_port *pt = SCM_PTAB_ENTRY (port);
  66   SCM stream = pt->stream;
  67
  68   if (pt->write_pos > pt->write_buf)
  69     {
  70       /* write the byte. */
  71       scm_apply (SCM_VELTS (stream)[0], SCM_MAKICHR (*pt->write_buf),
  72                  scm_listofnull);
  73       pt->write_pos = pt->write_buf;
  74
  75       /* flush the output.  */
  76       {
  77         SCM f = SCM_VELTS (stream)[2];
  78
  79         if (f != SCM_BOOL_F)
  80           scm_apply (f, SCM_EOL, SCM_EOL);
  81       }
  82     }
  83 }
  84
  85 static void
  86 sf_write (SCM port, void *data, size_t size)
  87 {
  88   SCM p = SCM_STREAM (port);
  89
  90   scm_apply (SCM_VELTS (p)[1], scm_cons (scm_makfrom0str ((char *) data),
  91                                          SCM_EOL),
  92              SCM_EOL);
  93 }
  94
  95 /* calling the flush proc (element 2) is in case old code needs it,
  96    but perhaps softports could the use port buffer in the same way as
  97    fports.  */
  98
  99 /* places a single char in the input buffer.  */
 100 static int
 101 sf_fill_input (SCM port)
 102 {
 103   SCM p = SCM_STREAM (port);
 104   SCM ans;
 105
 106   ans = scm_apply (SCM_VELTS (p)[3], SCM_EOL, SCM_EOL); /* get char.  */
 107   if (SCM_FALSEP (ans) || SCM_EOF_OBJECT_P (ans))
 108     return EOF;
 109   SCM_ASSERT (SCM_ICHRP (ans), ans, SCM_ARG1, "sf_fill_input");
 110   {
 111     scm_port *pt = SCM_PTAB_ENTRY (port);
 112
 113     *pt->read_buf = SCM_ICHR (ans);
 114     pt->read_pos = pt->read_buf;
 115     pt->read_end = pt->read_buf + 1;
 116     return *pt->read_buf;
 117   }
 118 }
 119
 120
 121 static int
 122 sf_close (SCM port)
 123 {
 124   SCM p = SCM_STREAM (port);
 125   SCM f = SCM_VELTS (p)[4];
 126   if (SCM_BOOL_F == f)
 127     return 0;
 128   f = scm_apply (f, SCM_EOL, SCM_EOL);
 129   errno = 0;
 130   return SCM_BOOL_F == f ? EOF : 0;
 131 }
 132
 133
 134
 135 SCM_PROC(s_make_soft_port, "make-soft-port", 2, 0, 0, scm_make_soft_port);
 136
 137 SCM
 138 scm_make_soft_port (pv, modes)
 139      SCM pv;
 140      SCM modes;
 141 {
 142   scm_port *pt;
 143   SCM z;
 144   SCM_ASSERT (SCM_NIMP (pv) && SCM_VECTORP (pv) && 5 == SCM_LENGTH (pv), pv, SCM_ARG1, s_make_soft_port);
 145   SCM_ASSERT (SCM_NIMP (modes) && SCM_ROSTRINGP (modes), modes, SCM_ARG2, s_make_soft_port);
 146   SCM_COERCE_SUBSTR (modes);
 147   SCM_NEWCELL (z);
 148   SCM_DEFER_INTS;
 149   pt = scm_add_to_port_table (z);
 150   SCM_SETCAR (z, scm_tc16_sfport | scm_mode_bits (SCM_ROCHARS (modes)));
 151   SCM_SETPTAB_ENTRY (z, pt);
 152   SCM_SETSTREAM (z, pv);
 153   pt->read_pos = pt->read_buf = pt->read_end = &pt->shortbuf;
 154   pt->write_buf = pt->write_pos = &pt->shortbuf;
 155   pt->read_buf_size = pt->write_buf_size = 1;
 156   pt->write_end = pt->write_buf + pt->write_buf_size;
 157   pt->rw_random = 0;
 158   SCM_ALLOW_INTS;
 159   return z;
 160 }
 161
 162
 163 void scm_make_sfptob (void); /* Called from ports.c */
 164
 165 void
 166 scm_make_sfptob ()
 167 {
 168   long tc = scm_make_port_type ("soft", sf_fill_input, sf_write);
 169   scm_set_port_mark (tc, scm_markstream);
 170   scm_set_port_flush (tc, sf_flush);
 171   scm_set_port_close (tc, sf_close);
 172 }
 173
 174 void
 175 scm_init_vports ()
 176 {
 177 #include "vports.x"
 178 }