libio/iofopncook.c

   1 /* Copyright (C) 1993, 1995, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU IO Library.
   3
   4    This library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU General Public License as
   6    published by the Free Software Foundation; either version 2, or (at
   7    your option) any later version.
   8
   9    This library is distributed in the hope that it will be useful, but
  10    WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this library; see the file COPYING.  If not, write to
  16    the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  17    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
  21    not cause the resulting executable to be covered by the GNU General
  22    Public License.  This exception does not however invalidate any
  23    other reasons why the executable file might be covered by the GNU
  24    General Public License.  */
  25
  26 #include <libioP.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29
  30
  31 /* Prototyped for local functions.  */
  32 static _IO_ssize_t _IO_cookie_read __P ((register _IO_FILE* fp, void* buf,
  33                                          _IO_ssize_t size));
  34 static _IO_ssize_t _IO_cookie_write __P ((register _IO_FILE* fp,
  35                                           const void* buf, _IO_ssize_t size));
  36 static _IO_fpos64_t _IO_cookie_seek __P ((_IO_FILE *fp, _IO_off64_t offset,
  37                                           int dir));
  38 static int _IO_cookie_close __P ((_IO_FILE* fp));
  39
  40
  41 static _IO_ssize_t
  42 _IO_cookie_read (fp, buf, size)
  43      _IO_FILE *fp;
  44      void *buf;
  45      _IO_ssize_t size;
  46 {
  47   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  48
  49   if (cfile->io_functions.read == NULL)
  50     return -1;
  51
  52   return cfile->io_functions.read (cfile->cookie, buf, size);
  53 }
  54
  55 static _IO_ssize_t
  56 _IO_cookie_write (fp, buf, size)
  57      _IO_FILE *fp;
  58      const void *buf;
  59      _IO_ssize_t size;
  60 {
  61   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  62
  63   if (cfile->io_functions.write == NULL)
  64     return -1;
  65
  66   return cfile->io_functions.write (cfile->cookie, buf, size);
  67 }
  68
  69 static _IO_fpos64_t
  70 _IO_cookie_seek (fp, offset, dir)
  71      _IO_FILE *fp;
  72      _IO_off64_t offset;
  73      int dir;
  74 {
  75   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  76   _IO_fpos64_t pos;
  77
  78   if (cfile->io_functions.seek == NULL)
  79     return _IO_pos_BAD;
  80
  81   pos = _IO_pos_0;
  82   _IO_pos_adjust (pos, offset);
  83
  84   if (cfile->io_functions.seek (cfile->cookie, pos, dir))
  85     return _IO_pos_BAD;
  86
  87   return pos;
  88 }
  89
  90 static int
  91 _IO_cookie_close (fp)
  92      _IO_FILE *fp;
  93 {
  94   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  95
  96   if (cfile->io_functions.close == NULL)
  97     return 0;
  98
  99   return cfile->io_functions.close (cfile->cookie);
 100 }
 101
 102
 103 static struct _IO_jump_t _IO_cookie_jumps = {
 104   JUMP_INIT_DUMMY,
 105   JUMP_INIT(finish, _IO_file_finish),
 106   JUMP_INIT(overflow, _IO_file_overflow),
 107   JUMP_INIT(underflow, _IO_file_underflow),
 108   JUMP_INIT(uflow, _IO_default_uflow),
 109   JUMP_INIT(pbackfail, _IO_default_pbackfail),
 110   JUMP_INIT(xsputn, _IO_file_xsputn),
 111   JUMP_INIT(xsgetn, _IO_default_xsgetn),
 112   JUMP_INIT(seekoff, _IO_file_seekoff),
 113   JUMP_INIT(seekpos, _IO_default_seekpos),
 114   JUMP_INIT(setbuf, _IO_file_setbuf),
 115   JUMP_INIT(sync, _IO_file_sync),
 116   JUMP_INIT(doallocate, _IO_file_doallocate),
 117   JUMP_INIT(read, _IO_cookie_read),
 118   JUMP_INIT(write, _IO_cookie_write),
 119   JUMP_INIT(seek, _IO_cookie_seek),
 120   JUMP_INIT(close, _IO_cookie_close),
 121   JUMP_INIT(stat, _IO_default_stat),
 122   JUMP_INIT(showmanyc, _IO_default_showmanyc),
 123   JUMP_INIT(imbue, _IO_default_imbue),
 124 };
 125
 126
 127 _IO_FILE *
 128 fopencookie (cookie, mode, io_functions)
 129      void *cookie;
 130      const char *mode;
 131      _IO_cookie_io_functions_t io_functions;
 132 {
 133   int read_write;
 134   struct locked_FILE
 135   {
 136     struct _IO_cookie_file cfile;
 137 #ifdef _IO_MTSAFE_IO
 138     _IO_lock_t lock;
 139 #endif
 140   } *new_f;
 141
 142   switch (*mode++)
 143     {
 144     case 'r':
 145       read_write = _IO_NO_WRITES;
 146       break;
 147     case 'w':
 148       read_write = _IO_NO_READS;
 149       break;
 150     case 'a':
 151       read_write = _IO_NO_READS|_IO_IS_APPENDING;
 152       break;
 153     default:
 154       return NULL;
 155   }
 156   if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
 157     read_write &= _IO_IS_APPENDING;
 158
 159   new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
 160   if (new_f == NULL)
 161     return NULL;
 162 #ifdef _IO_MTSAFE_IO
 163   new_f->cfile.file._lock = &new_f->lock;
 164 #endif
 165
 166   _IO_init (&new_f->cfile.file, 0);
 167   _IO_JUMPS (&new_f->cfile.file) = &_IO_cookie_jumps;
 168   new_f->cfile.cookie = cookie;
 169   new_f->cfile.io_functions = io_functions;
 170
 171   _IO_file_init(&new_f->cfile.file);
 172
 173   new_f->cfile.file._IO_file_flags =
 174     _IO_mask_flags (&new_f->cfile.file, read_write,
 175                     _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
 176
 177   return &new_f->cfile.file;
 178 }