libio/iofopncook.c

   1 /* Copyright (C) 1993,95,97,99,2000,2002,2004, 2005, 2010
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.
  19
  20    As a special exception, if you link the code in this file with
  21    files compiled with a GNU compiler to produce an executable,
  22    that does not cause the resulting executable to be covered by
  23    the GNU Lesser General Public License.  This exception does not
  24    however invalidate any other reasons why the executable file
  25    might be covered by the GNU Lesser General Public License.
  26    This exception applies to code released by its copyright holders
  27    in files containing the exception.  */
  28
  29 #include <libioP.h>
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <shlib-compat.h>
  33
  34 /* Prototyped for local functions.  */
  35 static _IO_ssize_t _IO_cookie_read (register _IO_FILE* fp, void* buf,
  36                                     _IO_ssize_t size);
  37 static _IO_ssize_t _IO_cookie_write (register _IO_FILE* fp,
  38                                      const void* buf, _IO_ssize_t size);
  39 static _IO_off64_t _IO_cookie_seek (_IO_FILE *fp, _IO_off64_t offset, int dir);
  40 static _IO_off64_t _IO_cookie_seekoff (_IO_FILE *fp, _IO_off64_t offset,
  41                                        int dir, int mode);
  42 static int _IO_cookie_close (_IO_FILE* fp);
  43
  44 static _IO_ssize_t
  45 _IO_cookie_read (fp, buf, size)
  46      _IO_FILE *fp;
  47      void *buf;
  48      _IO_ssize_t size;
  49 {
  50   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  51
  52   if (cfile->__io_functions.read == NULL)
  53     return -1;
  54
  55   return cfile->__io_functions.read (cfile->__cookie, buf, size);
  56 }
  57
  58 static _IO_ssize_t
  59 _IO_cookie_write (fp, buf, size)
  60      _IO_FILE *fp;
  61      const void *buf;
  62      _IO_ssize_t size;
  63 {
  64   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  65
  66   if (cfile->__io_functions.write == NULL)
  67     {
  68       fp->_flags |= _IO_ERR_SEEN;
  69       return 0;
  70     }
  71
  72   _IO_ssize_t n = cfile->__io_functions.write (cfile->__cookie, buf, size);
  73   if (n < size)
  74     fp->_flags |= _IO_ERR_SEEN;
  75
  76   return n;
  77 }
  78
  79 static _IO_off64_t
  80 _IO_cookie_seek (fp, offset, dir)
  81      _IO_FILE *fp;
  82      _IO_off64_t offset;
  83      int dir;
  84 {
  85   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  86
  87   return ((cfile->__io_functions.seek == NULL
  88            || (cfile->__io_functions.seek (cfile->__cookie, &offset, dir)
  89                == -1)
  90            || offset == (_IO_off64_t) -1)
  91           ? _IO_pos_BAD : offset);
  92 }
  93
  94 static int
  95 _IO_cookie_close (fp)
  96      _IO_FILE *fp;
  97 {
  98   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
  99
 100   if (cfile->__io_functions.close == NULL)
 101     return 0;
 102
 103   return cfile->__io_functions.close (cfile->__cookie);
 104 }
 105
 106
 107 static _IO_off64_t
 108 _IO_cookie_seekoff (fp, offset, dir, mode)
 109      _IO_FILE *fp;
 110      _IO_off64_t offset;
 111      int dir;
 112      int mode;
 113 {
 114   /* We must force the fileops code to always use seek to determine
 115      the position.  */
 116   fp->_offset = _IO_pos_BAD;
 117   return INTUSE(_IO_file_seekoff) (fp, offset, dir, mode);
 118 }
 119
 120
 121 static const struct _IO_jump_t _IO_cookie_jumps = {
 122   JUMP_INIT_DUMMY,
 123   JUMP_INIT(finish, INTUSE(_IO_file_finish)),
 124   JUMP_INIT(overflow, INTUSE(_IO_file_overflow)),
 125   JUMP_INIT(underflow, INTUSE(_IO_file_underflow)),
 126   JUMP_INIT(uflow, INTUSE(_IO_default_uflow)),
 127   JUMP_INIT(pbackfail, INTUSE(_IO_default_pbackfail)),
 128   JUMP_INIT(xsputn, INTUSE(_IO_file_xsputn)),
 129   JUMP_INIT(xsgetn, INTUSE(_IO_default_xsgetn)),
 130   JUMP_INIT(seekoff, _IO_cookie_seekoff),
 131   JUMP_INIT(seekpos, _IO_default_seekpos),
 132   JUMP_INIT(setbuf, INTUSE(_IO_file_setbuf)),
 133   JUMP_INIT(sync, INTUSE(_IO_file_sync)),
 134   JUMP_INIT(doallocate, INTUSE(_IO_file_doallocate)),
 135   JUMP_INIT(read, _IO_cookie_read),
 136   JUMP_INIT(write, _IO_cookie_write),
 137   JUMP_INIT(seek, _IO_cookie_seek),
 138   JUMP_INIT(close, _IO_cookie_close),
 139   JUMP_INIT(stat, _IO_default_stat),
 140   JUMP_INIT(showmanyc, _IO_default_showmanyc),
 141   JUMP_INIT(imbue, _IO_default_imbue),
 142 };
 143
 144
 145 void
 146 _IO_cookie_init (struct _IO_cookie_file *cfile, int read_write,
 147                  void *cookie, _IO_cookie_io_functions_t io_functions)
 148 {
 149   INTUSE(_IO_init) (&cfile->__fp.file, 0);
 150   _IO_JUMPS (&cfile->__fp) = &_IO_cookie_jumps;
 151
 152   cfile->__cookie = cookie;
 153   cfile->__io_functions = io_functions;
 154
 155   INTUSE(_IO_file_init) (&cfile->__fp);
 156
 157   _IO_mask_flags (&cfile->__fp.file, read_write,
 158                   _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
 159
 160   /* We use a negative number different from -1 for _fileno to mark that
 161      this special stream is not associated with a real file, but still has
 162      to be treated as such.  */
 163   cfile->__fp.file._fileno = -2;
 164 }
 165
 166
 167 _IO_FILE *
 168 _IO_fopencookie (cookie, mode, io_functions)
 169      void *cookie;
 170      const char *mode;
 171      _IO_cookie_io_functions_t io_functions;
 172 {
 173   int read_write;
 174   struct locked_FILE
 175   {
 176     struct _IO_cookie_file cfile;
 177 #ifdef _IO_MTSAFE_IO
 178     _IO_lock_t lock;
 179 #endif
 180   } *new_f;
 181
 182   switch (*mode++)
 183     {
 184     case 'r':
 185       read_write = _IO_NO_WRITES;
 186       break;
 187     case 'w':
 188       read_write = _IO_NO_READS;
 189       break;
 190     case 'a':
 191       read_write = _IO_NO_READS|_IO_IS_APPENDING;
 192       break;
 193     default:
 194       return NULL;
 195   }
 196   if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
 197     read_write &= _IO_IS_APPENDING;
 198
 199   new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
 200   if (new_f == NULL)
 201     return NULL;
 202 #ifdef _IO_MTSAFE_IO
 203   new_f->cfile.__fp.file._lock = &new_f->lock;
 204 #endif
 205
 206   _IO_cookie_init (&new_f->cfile, read_write, cookie, io_functions);
 207
 208   return (_IO_FILE *) &new_f->cfile.__fp;
 209 }
 210
 211 versioned_symbol (libc, _IO_fopencookie, fopencookie, GLIBC_2_2);
 212
 213 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)
 214
 215 static _IO_off64_t _IO_old_cookie_seek (_IO_FILE *fp, _IO_off64_t offset,
 216                                         int dir);
 217 _IO_FILE * _IO_old_fopencookie (void *cookie, const char *mode,
 218                                 _IO_cookie_io_functions_t io_functions);
 219
 220 static _IO_off64_t
 221 attribute_compat_text_section
 222 _IO_old_cookie_seek (fp, offset, dir)
 223      _IO_FILE *fp;
 224      _IO_off64_t offset;
 225      int dir;
 226 {
 227   struct _IO_cookie_file *cfile = (struct _IO_cookie_file *) fp;
 228   int (*seek) (_IO_FILE *, _IO_off_t, int);
 229   int ret;
 230
 231   seek = (int (*)(_IO_FILE *, _IO_off_t, int)) cfile->__io_functions.seek;
 232   if (seek == NULL)
 233     return _IO_pos_BAD;
 234
 235   ret = seek (cfile->__cookie, offset, dir);
 236
 237   return (ret == -1) ? _IO_pos_BAD : ret;
 238 }
 239
 240 static const struct _IO_jump_t _IO_old_cookie_jumps = {
 241   JUMP_INIT_DUMMY,
 242   JUMP_INIT(finish, INTUSE(_IO_file_finish)),
 243   JUMP_INIT(overflow, INTUSE(_IO_file_overflow)),
 244   JUMP_INIT(underflow, INTUSE(_IO_file_underflow)),
 245   JUMP_INIT(uflow, INTUSE(_IO_default_uflow)),
 246   JUMP_INIT(pbackfail, INTUSE(_IO_default_pbackfail)),
 247   JUMP_INIT(xsputn, INTUSE(_IO_file_xsputn)),
 248   JUMP_INIT(xsgetn, INTUSE(_IO_default_xsgetn)),
 249   JUMP_INIT(seekoff, _IO_cookie_seekoff),
 250   JUMP_INIT(seekpos, _IO_default_seekpos),
 251   JUMP_INIT(setbuf, INTUSE(_IO_file_setbuf)),
 252   JUMP_INIT(sync, INTUSE(_IO_file_sync)),
 253   JUMP_INIT(doallocate, INTUSE(_IO_file_doallocate)),
 254   JUMP_INIT(read, _IO_cookie_read),
 255   JUMP_INIT(write, _IO_cookie_write),
 256   JUMP_INIT(seek, _IO_old_cookie_seek),
 257   JUMP_INIT(close, _IO_cookie_close),
 258   JUMP_INIT(stat, _IO_default_stat),
 259   JUMP_INIT(showmanyc, _IO_default_showmanyc),
 260   JUMP_INIT(imbue, _IO_default_imbue),
 261 };
 262
 263 _IO_FILE *
 264 attribute_compat_text_section
 265 _IO_old_fopencookie (cookie, mode, io_functions)
 266      void *cookie;
 267      const char *mode;
 268      _IO_cookie_io_functions_t io_functions;
 269 {
 270   _IO_FILE *ret;
 271
 272   ret = _IO_fopencookie (cookie, mode, io_functions);
 273   if (ret != NULL)
 274     _IO_JUMPS ((struct _IO_FILE_plus *) ret) = &_IO_old_cookie_jumps;
 275
 276   return ret;
 277 }
 278
 279 compat_symbol (libc, _IO_old_fopencookie, fopencookie, GLIBC_2_0);
 280
 281 #endif