libio/iofopncook.c

   1 /*
   2 Copyright (C) 1993, 1995 Free Software Foundation
   3
   4 This file is part of the GNU IO Library.  This library is free
   5 software; you can redistribute it and/or modify it under the
   6 terms of the GNU General Public License as published by the
   7 Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 This library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this library; see the file COPYING.  If not, write to the Free
  17 Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19 As a special exception, if you link this library with files
  20 compiled with a GNU compiler to produce an executable, this does not cause
  21 the resulting executable to be covered by the GNU General Public License.
  22 This exception does not however invalidate any other reasons why
  23 the executable file might be covered by the GNU General Public License. */
  24
  25 #include <libioP.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28
  29
  30 /* Prototyped for local functions.  */
  31 static _IO_ssize_t _IO_cookie_read __P ((register _IO_FILE* fp, void* buf,
  32                                          _IO_ssize_t size));
  33 static _IO_ssize_t _IO_cookie_write __P ((register _IO_FILE* fp,
  34                                           const void* buf, _IO_ssize_t size));
  35 static _IO_fpos_t _IO_cookie_seek __P ((_IO_FILE *fp, _IO_off_t offset,
  36                                         int dir));
  37 static int _IO_cookie_close __P ((_IO_FILE* fp));
  38
  39
  40 static _IO_ssize_t
  41 _IO_cookie_read (fp, buf, size)
  42      register _IO_FILE* fp;
  43      void* buf;
  44      _IO_ssize_t size;
  45 {
  46   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  47
  48   if (cfile->io_functions.read == NULL)
  49     return -1;
  50
  51   return cfile->io_functions.read (cfile->cookie, buf, size);
  52 }
  53
  54 static _IO_ssize_t
  55 _IO_cookie_write (fp, buf, size)
  56      register _IO_FILE* fp;
  57      const void* buf;
  58      _IO_ssize_t size;
  59 {
  60   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  61
  62   if (cfile->io_functions.write == NULL)
  63     return -1;
  64
  65   return cfile->io_functions.write (cfile->cookie, buf, size);
  66 }
  67
  68 static _IO_fpos_t
  69 _IO_cookie_seek (fp, offset, dir)
  70      _IO_FILE *fp;
  71      _IO_off_t offset;
  72      int dir;
  73 {
  74   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  75   _IO_fpos_t pos;
  76
  77   if (cfile->io_functions.seek == NULL)
  78     return _IO_pos_BAD;
  79
  80   pos = _IO_pos_0;
  81   _IO_pos_adjust (pos, offset);
  82
  83   if (cfile->io_functions.seek (cfile->cookie, pos, dir))
  84     return _IO_pos_BAD;
  85
  86   return pos;
  87 }
  88
  89 static int
  90 _IO_cookie_close (fp)
  91      _IO_FILE* fp;
  92 {
  93   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  94
  95   if (cfile->io_functions.close == NULL)
  96     return 0;
  97
  98   return cfile->io_functions.close (cfile->cookie);
  99 }
 100
 101
 102 static struct _IO_jump_t _IO_cookie_jumps = {
 103   JUMP_INIT_DUMMY,
 104   JUMP_INIT(finish, _IO_file_finish),
 105   JUMP_INIT(overflow, _IO_file_overflow),
 106   JUMP_INIT(underflow, _IO_file_underflow),
 107   JUMP_INIT(uflow, _IO_default_uflow),
 108   JUMP_INIT(pbackfail, _IO_default_pbackfail),
 109   JUMP_INIT(xsputn, _IO_file_xsputn),
 110   JUMP_INIT(xsgetn, _IO_default_xsgetn),
 111   JUMP_INIT(seekoff, _IO_file_seekoff),
 112   JUMP_INIT(seekpos, _IO_default_seekpos),
 113   JUMP_INIT(setbuf, _IO_file_setbuf),
 114   JUMP_INIT(sync, _IO_file_sync),
 115   JUMP_INIT(doallocate, _IO_file_doallocate),
 116   JUMP_INIT(read, _IO_cookie_read),
 117   JUMP_INIT(write, _IO_cookie_write),
 118   JUMP_INIT(seek, _IO_cookie_seek),
 119   JUMP_INIT(close, _IO_cookie_close),
 120   JUMP_INIT(stat, _IO_default_stat)
 121 };
 122
 123
 124 _IO_FILE *
 125 fopencookie (cookie, mode, io_functions)
 126      void *cookie;
 127      const char *mode;
 128      _IO_cookie_io_functions_t io_functions;
 129 {
 130   int read_write;
 131   struct _IO_cookie_file *cfile;
 132
 133   switch (*mode++)
 134     {
 135     case 'r':
 136       read_write = _IO_NO_WRITES;
 137       break;
 138     case 'w':
 139       read_write = _IO_NO_READS;
 140       break;
 141     case 'a':
 142       read_write = _IO_NO_READS|_IO_IS_APPENDING;
 143       break;
 144     default:
 145       return NULL;
 146   }
 147   if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
 148     read_write &= _IO_IS_APPENDING;
 149
 150   cfile  = (struct _IO_cookie_file *) malloc (sizeof (struct _IO_cookie_file));
 151   if (cfile == NULL)
 152     return NULL;
 153
 154   _IO_init (&cfile->file, 0);
 155   _IO_JUMPS (&cfile->file) = &_IO_cookie_jumps;
 156   cfile->cookie = cookie;
 157   cfile->io_functions = io_functions;
 158
 159   _IO_file_init(&cfile->file);
 160
 161   cfile->file._IO_file_flags =
 162     _IO_mask_flags (&cfile->file, read_write,
 163                     _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
 164
 165   return &cfile->file;
 166 }
 167