1 /* Copyright (C) 1995-2022 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, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include "libioP.h"
19 #include "strfile.h"
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <wchar.h>
23 
24 
25 struct _IO_FILE_wmemstream
26 {
27   _IO_strfile _sf;
28   wchar_t **bufloc;
29   size_t *sizeloc;
30 };
31 
32 
33 static int _IO_wmem_sync (FILE* fp) __THROW;
34 static void _IO_wmem_finish (FILE* fp, int) __THROW;
35 
36 
37 static const struct _IO_jump_t _IO_wmem_jumps libio_vtable =
38 {
39   JUMP_INIT_DUMMY,
40   JUMP_INIT (finish, _IO_wmem_finish),
41   JUMP_INIT (overflow, (_IO_overflow_t) _IO_wstr_overflow),
42   JUMP_INIT (underflow, (_IO_underflow_t) _IO_wstr_underflow),
43   JUMP_INIT (uflow, (_IO_underflow_t) _IO_wdefault_uflow),
44   JUMP_INIT (pbackfail, (_IO_pbackfail_t) _IO_wstr_pbackfail),
45   JUMP_INIT (xsputn, _IO_wdefault_xsputn),
46   JUMP_INIT (xsgetn, _IO_wdefault_xsgetn),
47   JUMP_INIT (seekoff, _IO_wstr_seekoff),
48   JUMP_INIT (seekpos, _IO_default_seekpos),
49   JUMP_INIT (setbuf, _IO_default_setbuf),
50   JUMP_INIT (sync, _IO_wmem_sync),
51   JUMP_INIT (doallocate, _IO_wdefault_doallocate),
52   JUMP_INIT (read, _IO_default_read),
53   JUMP_INIT (write, _IO_default_write),
54   JUMP_INIT (seek, _IO_default_seek),
55   JUMP_INIT (close, _IO_default_close),
56   JUMP_INIT (stat, _IO_default_stat),
57   JUMP_INIT (showmanyc, _IO_default_showmanyc),
58   JUMP_INIT (imbue, _IO_default_imbue)
59 };
60 
61 /* Open a stream that writes into a malloc'd buffer that is expanded as
62    necessary.  *BUFLOC and *SIZELOC are updated with the buffer's location
63    and the number of characters written on fflush or fclose.  */
64 FILE *
open_wmemstream(wchar_t ** bufloc,size_t * sizeloc)65 open_wmemstream (wchar_t **bufloc, size_t *sizeloc)
66 {
67   struct locked_FILE
68   {
69     struct _IO_FILE_wmemstream fp;
70 #ifdef _IO_MTSAFE_IO
71     _IO_lock_t lock;
72 #endif
73     struct _IO_wide_data wd;
74   } *new_f;
75   wchar_t *buf;
76 
77   new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
78   if (new_f == NULL)
79     return NULL;
80 #ifdef _IO_MTSAFE_IO
81   new_f->fp._sf._sbf._f._lock = &new_f->lock;
82 #endif
83 
84   buf = calloc (1, BUFSIZ);
85   if (buf == NULL)
86     {
87       free (new_f);
88       return NULL;
89     }
90   _IO_no_init (&new_f->fp._sf._sbf._f, 0, 0, &new_f->wd, &_IO_wmem_jumps);
91   _IO_fwide (&new_f->fp._sf._sbf._f, 1);
92   _IO_wstr_init_static (&new_f->fp._sf._sbf._f, buf,
93 			BUFSIZ / sizeof (wchar_t), buf);
94   new_f->fp._sf._sbf._f._flags2 &= ~_IO_FLAGS2_USER_WBUF;
95   new_f->fp._sf._s._allocate_buffer_unused = (_IO_alloc_type) malloc;
96   new_f->fp._sf._s._free_buffer_unused = (_IO_free_type) free;
97 
98   new_f->fp.bufloc = bufloc;
99   new_f->fp.sizeloc = sizeloc;
100 
101   /* Disable single thread optimization.  BZ 21735.  */
102   new_f->fp._sf._sbf._f._flags2 |= _IO_FLAGS2_NEED_LOCK;
103 
104   return (FILE *) &new_f->fp._sf._sbf;
105 }
106 
107 
108 static int
_IO_wmem_sync(FILE * fp)109 _IO_wmem_sync (FILE *fp)
110 {
111   struct _IO_FILE_wmemstream *mp = (struct _IO_FILE_wmemstream *) fp;
112 
113   if (fp->_wide_data->_IO_write_ptr == fp->_wide_data->_IO_write_end)
114     {
115       _IO_wstr_overflow (fp, '\0');
116       --fp->_wide_data->_IO_write_ptr;
117     }
118 
119   *mp->bufloc = fp->_wide_data->_IO_write_base;
120   *mp->sizeloc = (fp->_wide_data->_IO_write_ptr
121 		  - fp->_wide_data->_IO_write_base);
122 
123   return 0;
124 }
125 
126 
127 static void
_IO_wmem_finish(FILE * fp,int dummy)128 _IO_wmem_finish (FILE *fp, int dummy)
129 {
130   struct _IO_FILE_wmemstream *mp = (struct _IO_FILE_wmemstream *) fp;
131 
132   *mp->bufloc = (wchar_t *) realloc (fp->_wide_data->_IO_write_base,
133 				     (fp->_wide_data->_IO_write_ptr
134 				      - fp->_wide_data->_IO_write_base + 1)
135 				     * sizeof (wchar_t));
136   if (*mp->bufloc != NULL)
137     {
138       size_t len = (fp->_wide_data->_IO_write_ptr
139 		    - fp->_wide_data->_IO_write_base);
140       (*mp->bufloc)[len] = '\0';
141       *mp->sizeloc = len;
142 
143       fp->_wide_data->_IO_buf_base = NULL;
144     }
145 
146   _IO_wstr_finish (fp, 0);
147 }
148