1/* Copyright (C) 1994,1997,1999,2000,2001,2002 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 Lesser General Public
6   License as published by the Free Software Foundation; either
7   version 2.1 of the 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   Lesser General Public License for more details.
13
14   You should have received a copy of the GNU Lesser General Public
15   License along with the GNU C Library; if not, write to the Free
16   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17   02111-1307 USA.
18
19   As a special exception, if you link the code in this file with
20   files compiled with a GNU compiler to produce an executable,
21   that does not cause the resulting executable to be covered by
22   the GNU Lesser General Public License.  This exception does not
23   however invalidate any other reasons why the executable file
24   might be covered by the GNU Lesser General Public License.
25   This exception applies to code released by its copyright holders
26   in files containing the exception.  */
27
28#include "libioP.h"
29#include "strfile.h"
30
31
32typedef struct
33{
34  _IO_strfile f;
35  /* This is used for the characters which do not fit in the buffer
36     provided by the user.  */
37  wchar_t overflow_buf[64];
38} _IO_strnfile;
39
40
41static wint_t _IO_wstrn_overflow __P ((_IO_FILE *fp, wint_t c));
42
43static wint_t
44_IO_wstrn_overflow (fp, c)
45     _IO_FILE *fp;
46     wint_t c;
47{
48  /* When we come to here this means the user supplied buffer is
49     filled.  But since we must return the number of characters which
50     would have been written in total we must provide a buffer for
51     further use.  We can do this by writing on and on in the overflow
52     buffer in the _IO_strnfile structure.  */
53  _IO_strnfile *snf = (_IO_strnfile *) fp;
54
55  if (fp->_wide_data->_IO_buf_base != snf->overflow_buf)
56    {
57      INTUSE(_IO_wsetb) (fp, snf->overflow_buf,
58			 snf->overflow_buf + (sizeof (snf->overflow_buf)
59					      / sizeof (wchar_t)), 0);
60
61      fp->_wide_data->_IO_write_base = snf->overflow_buf;
62      fp->_wide_data->_IO_read_base = snf->overflow_buf;
63      fp->_wide_data->_IO_read_ptr = snf->overflow_buf;
64      fp->_wide_data->_IO_read_end = (snf->overflow_buf
65				      + (sizeof (snf->overflow_buf)
66					 / sizeof (wchar_t)));
67    }
68
69  fp->_wide_data->_IO_write_ptr = snf->overflow_buf;
70  fp->_wide_data->_IO_write_end = snf->overflow_buf;
71
72  /* Since we are not really interested in storing the characters
73     which do not fit in the buffer we simply ignore it.  */
74  return c;
75}
76
77
78static struct _IO_jump_t _IO_wstrn_jumps =
79{
80  JUMP_INIT_DUMMY,
81  JUMP_INIT(finish, _IO_wstr_finish),
82  JUMP_INIT(overflow, (_IO_overflow_t) _IO_wstrn_overflow),
83  JUMP_INIT(underflow, (_IO_underflow_t) _IO_wstr_underflow),
84  JUMP_INIT(uflow, (_IO_underflow_t) INTUSE(_IO_wdefault_uflow)),
85  JUMP_INIT(pbackfail, (_IO_pbackfail_t) _IO_wstr_pbackfail),
86  JUMP_INIT(xsputn, INTUSE(_IO_wdefault_xsputn)),
87  JUMP_INIT(xsgetn, INTUSE(_IO_wdefault_xsgetn)),
88  JUMP_INIT(seekoff, _IO_wstr_seekoff),
89  JUMP_INIT(seekpos, _IO_default_seekpos),
90  JUMP_INIT(setbuf, _IO_default_setbuf),
91  JUMP_INIT(sync, _IO_default_sync),
92  JUMP_INIT(doallocate, INTUSE(_IO_wdefault_doallocate)),
93  JUMP_INIT(read, _IO_default_read),
94  JUMP_INIT(write, _IO_default_write),
95  JUMP_INIT(seek, _IO_default_seek),
96  JUMP_INIT(close, _IO_default_close),
97  JUMP_INIT(stat, _IO_default_stat),
98  JUMP_INIT(showmanyc, _IO_default_showmanyc),
99  JUMP_INIT(imbue, _IO_default_imbue)
100};
101
102
103int
104_IO_vswprintf (string, maxlen, format, args)
105     wchar_t *string;
106     _IO_size_t maxlen;
107     const wchar_t *format;
108     _IO_va_list args;
109{
110  _IO_strnfile sf;
111  int ret;
112  struct _IO_wide_data wd;
113#ifdef _IO_MTSAFE_IO
114  sf.f._sbf._f._lock = NULL;
115#endif
116
117  if (maxlen == 0)
118    /* Since we have to write at least the terminating L'\0' a buffer
119       length of zero always makes the function fail.  */
120    return -1;
121
122  _IO_no_init (&sf.f._sbf._f, _IO_USER_LOCK, 0, &wd, &_IO_wstrn_jumps);
123  _IO_fwide (&sf.f._sbf._f, 1);
124  string[0] = L'\0';
125  _IO_wstr_init_static (&sf.f._sbf._f, string, maxlen - 1, string);
126  ret = _IO_vfwprintf ((_IO_FILE *) &sf.f._sbf, format, args);
127
128  if (sf.f._sbf._f._wide_data->_IO_buf_base == sf.overflow_buf)
129    /* ISO C99 requires swprintf/vswprintf to return an error if the
130       output does not fit int he provided buffer.  */
131    return -1;
132
133  /* Terminate the string.  */
134  *sf.f._sbf._f._wide_data->_IO_write_ptr = '\0';
135
136  return ret;
137}
138
139#ifdef weak_alias
140weak_alias (_IO_vswprintf, __vswprintf)
141weak_alias (_IO_vswprintf, vswprintf)
142#endif
143