summaryrefslogtreecommitdiff
path: root/libio/memstream.c
blob: 71519a51906ac210cd86f199d19ee1f576e06f25 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/* Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#include "strfile.h"
#include "libioP.h"
#include <stdlib.h>


struct _IO_FILE_memstream
{
  _IO_strfile _sf;
  char **bufloc;
  _IO_size_t *sizeloc;
};


static int _IO_mem_sync __P ((_IO_FILE* fp));
static void _IO_mem_finish __P ((_IO_FILE* fp));


static const struct _IO_jump_t _IO_mem_jumps =
{
  JUMP_INIT_DUMMY,
  JUMP_INIT (finish, _IO_mem_finish),
  JUMP_INIT (overflow, _IO_str_overflow),
  JUMP_INIT (underflow, _IO_str_underflow),
  JUMP_INIT (uflow, _IO_default_uflow),
  JUMP_INIT (pbackfail, _IO_str_pbackfail),
  JUMP_INIT (xsputn, _IO_default_xsputn),
  JUMP_INIT (xsgetn, _IO_default_xsgetn),
  JUMP_INIT (seekoff, _IO_str_seekoff),
  JUMP_INIT (seekpos, _IO_default_seekpos),
  JUMP_INIT (setbuf, _IO_default_setbuf),
  JUMP_INIT (sync, _IO_mem_sync),
  JUMP_INIT (doallocate, _IO_default_doallocate),
  JUMP_INIT (read, _IO_default_read),
  JUMP_INIT (write, _IO_default_write),
  JUMP_INIT (seek, _IO_default_seek),
  JUMP_INIT (close, _IO_default_close),
  JUMP_INIT (stat, _IO_default_stat)
};

/* Open a stream that writes into a malloc'd buffer that is expanded as
   necessary.  *BUFLOC and *SIZELOC are updated with the buffer's location
   and the number of characters written on fflush or fclose.  */
_IO_FILE *
open_memstream (bufloc, sizeloc)
     char **bufloc;
     _IO_size_t *sizeloc;
{
  struct _IO_FILE_memstream *fp;
  char *buf;

  fp = (struct _IO_FILE_memstream *)
    malloc (sizeof (struct _IO_FILE_memstream));
  if (fp == NULL)
    return NULL;

  buf = ALLOC_BUF (_IO_BUFSIZ);
  _IO_init (&fp->_sf._f, 0);
  _IO_JUMPS (&fp->_sf._f) = &_IO_mem_jumps;
  _IO_str_init_static (&fp->_sf._f, buf, _IO_BUFSIZ, buf);
  fp->_sf._f._flags &= ~_IO_USER_BUF;
  fp->_sf._s._allocate_buffer = (_IO_alloc_type) malloc;
  fp->_sf._s._free_buffer = (_IO_free_type) free;

  fp->bufloc = bufloc;
  fp->sizeloc = sizeloc;

  return &fp->_sf._f;
}


static int
_IO_mem_sync (fp)
     _IO_FILE* fp;
{
  struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;
  int res;

  res = _IO_default_sync (fp);
  if (res < 0)
    return res;

  if (fp->_IO_write_ptr == fp->_IO_write_end)
    {
      _IO_str_overflow (fp, '\0');
      --fp->_IO_write_ptr;
    }
  else
    *fp->_IO_write_ptr = '\0';

  *mp->bufloc = fp->_IO_write_base;
  *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;

  return 0;
}


static void
_IO_mem_finish (fp)
     _IO_FILE* fp;
{
  struct _IO_FILE_memstream *mp = (struct _IO_FILE_memstream *) fp;

  *mp->bufloc = (char *) realloc (fp->_IO_write_base,
				  fp->_IO_write_ptr - fp->_IO_write_base + 1);
  if (*mp->bufloc != NULL)
    {
      (*mp->bufloc)[fp->_IO_write_ptr - fp->_IO_write_base] = '\0';
      *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base;
    }

  fp->_IO_buf_base = NULL;

  _IO_default_finish (fp);
}