libio/memstream.c

   1 /* Copyright (C) 1995, 1996, 1997, 1999 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include "libioP.h"
  20 #include "strfile.h"
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23
  24
  25 struct _IO_FILE_memstream
  26 {
  27   _IO_strfile _sf;
  28   char **bufloc;
  29   _IO_size_t *sizeloc;
  30 };
  31
  32
  33 static int _IO_mem_sync __P ((_IO_FILE* fp));
  34 static void _IO_mem_finish __P ((_IO_FILE* fp, int));
  35 static int _IO_wmem_sync __P ((_IO_FILE* fp));
  36 static void _IO_wmem_finish __P ((_IO_FILE* fp, int));
  37
  38
  39 static struct _IO_jump_t _IO_mem_jumps =
  40 {
  41   JUMP_INIT_DUMMY,
  42   JUMP_INIT (finish, _IO_mem_finish),
  43   JUMP_INIT (overflow, _IO_str_overflow),
  44   JUMP_INIT (underflow, _IO_str_underflow),
  45   JUMP_INIT (uflow, _IO_default_uflow),
  46   JUMP_INIT (pbackfail, _IO_str_pbackfail),
  47   JUMP_INIT (xsputn, _IO_default_xsputn),
  48   JUMP_INIT (xsgetn, _IO_default_xsgetn),
  49   JUMP_INIT (seekoff, _IO_str_seekoff),
  50   JUMP_INIT (seekpos, _IO_default_seekpos),
  51   JUMP_INIT (setbuf, _IO_default_setbuf),
  52   JUMP_INIT (sync, _IO_mem_sync),
  53   JUMP_INIT (doallocate, _IO_default_doallocate),
  54   JUMP_INIT (read, _IO_default_read),
  55   JUMP_INIT (write, _IO_default_write),
  56   JUMP_INIT (seek, _IO_default_seek),
  57   JUMP_INIT (close, _IO_default_close),
  58   JUMP_INIT (stat, _IO_default_stat),
  59   JUMP_INIT(showmanyc, _IO_default_showmanyc),
  60   JUMP_INIT(imbue, _IO_default_imbue)
  61 };
  62
  63 static struct _IO_jump_t _IO_wmem_jumps =
  64 {
  65   JUMP_INIT_DUMMY,
  66   JUMP_INIT (finish, (_IO_finish_t) _IO_wmem_finish),
  67   JUMP_INIT (overflow, (_IO_overflow_t) _IO_wstr_overflow),
  68   JUMP_INIT (underflow, (_IO_underflow_t) _IO_wstr_underflow),
  69   JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
  70   JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wstr_pbackfail),
  71   JUMP_INIT (xsputn, (_IO_xsputn_t) _IO_wdefault_xsputn),
  72   JUMP_INIT (xsgetn, (_IO_xsgetn_t) _IO_wdefault_xsgetn),
  73   JUMP_INIT (seekoff, _IO_wstr_seekoff),
  74   JUMP_INIT (seekpos, _IO_default_seekpos),
  75   JUMP_INIT (setbuf, (_IO_setbuf_t) _IO_wdefault_setbuf),
  76   JUMP_INIT (sync, (_IO_sync_t) _IO_wmem_sync),
  77   JUMP_INIT (doallocate, _IO_wdefault_doallocate),
  78   JUMP_INIT (read, _IO_default_read),
  79   JUMP_INIT (write, _IO_default_write),
  80   JUMP_INIT (seek, _IO_default_seek),
  81   JUMP_INIT (close, _IO_default_close),
  82   JUMP_INIT (stat, _IO_default_stat),
  83   JUMP_INIT(showmanyc, _IO_default_showmanyc),
  84   JUMP_INIT(imbue, _IO_default_imbue)
  85 };
  86
  87 /* Open a stream that writes into a malloc'd buffer that is expanded as
  88    necessary.  *BUFLOC and *SIZELOC are updated with the buffer's location
  89    and the number of characters written on fflush or fclose.  */
  90 _IO_FILE *
  91 open_memstream (bufloc, sizeloc)
  92      char **bufloc;
  93      _IO_size_t *sizeloc;
  94 {
  95   struct locked_FILE
  96   {
  97     struct _IO_FILE_memstream fp;
  98 #ifdef _IO_MTSAFE_IO
  99     _IO_lock_t lock;
 100 #endif
 101     struct _IO_wide_data wd;
 102   } *new_f;
 103   char *buf;
 104
 105   new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
 106   if (new_f == NULL)
 107     return NULL;
 108 #ifdef _IO_MTSAFE_IO
 109   new_f->fp._sf._sbf._f._lock = &new_f->lock;
 110 #endif
 111
 112   buf = malloc (_IO_BUFSIZ);
 113   if (buf == NULL)
 114     return NULL;
 115   _IO_no_init (&new_f->fp._sf._sbf._f, 0, 0, &new_f->wd, &_IO_wmem_jumps);
 116   _IO_JUMPS (&new_f->fp._sf._sbf._f) = &_IO_mem_jumps;
 117   _IO_str_init_static (&new_f->fp._sf._sbf._f, buf, _IO_BUFSIZ, buf);
 118   new_f->fp._sf._sbf._f._flags &= ~_IO_USER_BUF;
 119   new_f->fp._sf._s._allocate_buffer = (_IO_alloc_type) malloc;
 120   new_f->fp._sf._s._free_buffer = (_IO_free_type) free;
 121
 122   new_f->fp.bufloc = bufloc;
 123   new_f->fp.sizeloc = sizeloc;
 124
 125   return &new_f->fp._sf._sbf._f;
 126 }
 127
 128
 129 static int
 130 _IO_mem_sync (fp)
 131      _IO_FILE* fp;
 132 {
 133   struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;
 134   int res;
 135
 136   res = _IO_default_sync (fp);
 137   if (res < 0)
 138     return res;
 139
 140   if (fp->_IO_write_ptr == fp->_IO_write_end)
 141     {
 142       _IO_str_overflow (fp, '\0');
 143       --fp->_IO_write_ptr;
 144     }
 145   else
 146     *fp->_IO_write_ptr = '\0';
 147
 148   *mp->bufloc = fp->_IO_write_base;
 149   *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;
 150
 151   return 0;
 152 }
 153
 154
 155 static void
 156 _IO_mem_finish (fp, dummy)
 157      _IO_FILE* fp;
 158      int dummy;
 159 {
 160   struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;
 161
 162   *mp->bufloc = (char *) realloc (fp->_IO_write_base,
 163                                   fp->_IO_write_ptr - fp->_IO_write_base + 1);
 164   if (*mp->bufloc != NULL)
 165     {
 166       (*mp->bufloc)[fp->_IO_write_ptr - fp->_IO_write_base] = '\0';
 167       *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;
 168     }
 169
 170   fp->_IO_buf_base = NULL;
 171
 172   _IO_default_finish (fp, 0);
 173 }
 174
 175
 176 static int
 177 _IO_wmem_sync (fp)
 178      _IO_FILE* fp;
 179 {
 180   struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;
 181   int res;
 182
 183   res = _IO_default_sync (fp);
 184   if (res < 0)
 185     return res;
 186
 187   if (fp->_wide_data->_IO_write_ptr == fp->_wide_data->_IO_write_end)
 188     {
 189       _IO_wstr_overflow (fp, L'\0');
 190       --fp->_wide_data->_IO_write_ptr;
 191     }
 192   else
 193     *fp->_wide_data->_IO_write_ptr = '\0';
 194
 195   *mp->bufloc = (char *) fp->_wide_data->_IO_write_base;
 196   *mp->sizeloc = (fp->_wide_data->_IO_write_ptr
 197                   - fp->_wide_data->_IO_write_base);
 198
 199   return 0;
 200 }
 201
 202
 203 static void
 204 _IO_wmem_finish (fp, dummy)
 205      _IO_FILE* fp;
 206      int dummy;
 207 {
 208   struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;
 209
 210   *mp->bufloc = (char *) realloc (fp->_wide_data->_IO_write_base,
 211                                   (fp->_wide_data->_IO_write_ptr
 212                                    - fp->_wide_data->_IO_write_base + 1)
 213                                   * sizeof (wchar_t));
 214   if (*mp->bufloc != NULL)
 215     {
 216       ((wchar_t *) (*mp->bufloc))[fp->_wide_data->_IO_write_ptr
 217                                  - fp->_wide_data->_IO_write_base] = '\0';
 218       *mp->sizeloc = (fp->_wide_data->_IO_write_ptr
 219                       - fp->_wide_data->_IO_write_base);
 220     }
 221
 222   fp->_wide_data->_IO_buf_base = NULL;
 223
 224   _IO_default_finish (fp, 0);
 225 }