1 /* Copyright (C) 1991-2022 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    As a special exception, if you link the code in this file with
19    files compiled with a GNU compiler to produce an executable,
20    that does not cause the resulting executable to be covered by
21    the GNU Lesser General Public License.  This exception does not
22    however invalidate any other reasons why the executable file
23    might be covered by the GNU Lesser General Public License.
24    This exception applies to code released by its copyright holders
25    in files containing the exception.  */
26 
27 #ifndef _LIBIO_H
28 #define _LIBIO_H 1
29 
30 #ifndef _LIBC
31 # error "libio.h should only be included when building glibc itself"
32 #endif
33 #ifdef _ISOMAC
34 # error "libio.h should not be included under _ISOMAC"
35 #endif
36 
37 #include <stdio.h>
38 
39 #if defined _IO_MTSAFE_IO && !defined _IO_lock_t_defined
40 # error "Someone forgot to include stdio-lock.h"
41 #endif
42 
43 #define __need_wchar_t
44 #include <stddef.h>
45 
46 #include <bits/types/__mbstate_t.h>
47 #include <bits/types/wint_t.h>
48 #include <gconv.h>
49 
50 typedef struct
51 {
52   struct __gconv_step *step;
53   struct __gconv_step_data step_data;
54 } _IO_iconv_t;
55 
56 #include <shlib-compat.h>
57 
58 /* _IO_seekoff modes */
59 #define _IOS_INPUT	1
60 #define _IOS_OUTPUT	2
61 
62 /* Magic number and bits for the _flags field.  The magic number is
63    mostly vestigial, but preserved for compatibility.  It occupies the
64    high 16 bits of _flags; the low 16 bits are actual flag bits.  */
65 
66 #define _IO_MAGIC         0xFBAD0000 /* Magic number */
67 #define _IO_MAGIC_MASK    0xFFFF0000
68 #define _IO_USER_BUF          0x0001 /* Don't deallocate buffer on close. */
69 #define _IO_UNBUFFERED        0x0002
70 #define _IO_NO_READS          0x0004 /* Reading not allowed.  */
71 #define _IO_NO_WRITES         0x0008 /* Writing not allowed.  */
72 #define _IO_EOF_SEEN          0x0010
73 #define _IO_ERR_SEEN          0x0020
74 #define _IO_DELETE_DONT_CLOSE 0x0040 /* Don't call close(_fileno) on close.  */
75 #define _IO_LINKED            0x0080 /* In the list of all open files.  */
76 #define _IO_IN_BACKUP         0x0100
77 #define _IO_LINE_BUF          0x0200
78 #define _IO_TIED_PUT_GET      0x0400 /* Put and get pointer move in unison.  */
79 #define _IO_CURRENTLY_PUTTING 0x0800
80 #define _IO_IS_APPENDING      0x1000
81 #define _IO_IS_FILEBUF        0x2000
82                            /* 0x4000  No longer used, reserved for compat.  */
83 #define _IO_USER_LOCK         0x8000
84 
85 /* Bits for the _flags2 field.  */
86 #define _IO_FLAGS2_MMAP 1
87 #define _IO_FLAGS2_NOTCANCEL 2
88 #define _IO_FLAGS2_USER_WBUF 8
89 #define _IO_FLAGS2_NOCLOSE 32
90 #define _IO_FLAGS2_CLOEXEC 64
91 #define _IO_FLAGS2_NEED_LOCK 128
92 
93 /* _IO_pos_BAD is an off64_t value indicating error, unknown, or EOF.  */
94 #define _IO_pos_BAD ((off64_t) -1)
95 
96 /* _IO_pos_adjust adjusts an off64_t by some number of bytes.  */
97 #define _IO_pos_adjust(pos, delta) ((pos) += (delta))
98 
99 /* _IO_pos_0 is an off64_t value indicating beginning of file.  */
100 #define _IO_pos_0 ((off64_t) 0)
101 
102 struct _IO_jump_t;
103 
104 /* A streammarker remembers a position in a buffer. */
105 struct _IO_marker {
106   struct _IO_marker *_next;
107   FILE *_sbuf;
108   /* If _pos >= 0
109  it points to _buf->Gbase()+_pos. FIXME comment */
110   /* if _pos < 0, it points to _buf->eBptr()+_pos. FIXME comment */
111   int _pos;
112 };
113 
114 struct _IO_codecvt
115 {
116   _IO_iconv_t __cd_in;
117   _IO_iconv_t __cd_out;
118 };
119 
120 /* Extra data for wide character streams.  */
121 struct _IO_wide_data
122 {
123   wchar_t *_IO_read_ptr;	/* Current read pointer */
124   wchar_t *_IO_read_end;	/* End of get area. */
125   wchar_t *_IO_read_base;	/* Start of putback+get area. */
126   wchar_t *_IO_write_base;	/* Start of put area. */
127   wchar_t *_IO_write_ptr;	/* Current put pointer. */
128   wchar_t *_IO_write_end;	/* End of put area. */
129   wchar_t *_IO_buf_base;	/* Start of reserve area. */
130   wchar_t *_IO_buf_end;		/* End of reserve area. */
131   /* The following fields are used to support backing up and undo. */
132   wchar_t *_IO_save_base;	/* Pointer to start of non-current get area. */
133   wchar_t *_IO_backup_base;	/* Pointer to first valid character of
134 				   backup area */
135   wchar_t *_IO_save_end;	/* Pointer to end of non-current get area. */
136 
137   __mbstate_t _IO_state;
138   __mbstate_t _IO_last_state;
139   struct _IO_codecvt _codecvt;
140 
141   wchar_t _shortbuf[1];
142 
143   const struct _IO_jump_t *_wide_vtable;
144 };
145 
146 struct _IO_FILE_plus;
147 
148 extern struct _IO_FILE_plus _IO_2_1_stdin_;
149 extern struct _IO_FILE_plus _IO_2_1_stdout_;
150 extern struct _IO_FILE_plus _IO_2_1_stderr_;
151 
152 struct _IO_cookie_file;
153 
154 /* Initialize one of those.  */
155 extern void _IO_cookie_init (struct _IO_cookie_file *__cfile, int __read_write,
156 			     void *__cookie, cookie_io_functions_t __fns);
157 
158 extern int __underflow (FILE *);
159 extern wint_t __wunderflow (FILE *);
160 extern wint_t __wuflow (FILE *);
161 extern wint_t __woverflow (FILE *, wint_t);
162 
163 #define _IO_getc_unlocked(_fp) __getc_unlocked_body (_fp)
164 #define _IO_peekc_unlocked(_fp)						\
165   (__glibc_unlikely ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end)	\
166    && __underflow (_fp) == EOF						\
167    ? EOF								\
168    : *(unsigned char *) (_fp)->_IO_read_ptr)
169 #define _IO_putc_unlocked(_ch, _fp) __putc_unlocked_body (_ch, _fp)
170 
171 # define _IO_getwc_unlocked(_fp)					\
172   (__glibc_unlikely ((_fp)->_wide_data == NULL				\
173 		     || ((_fp)->_wide_data->_IO_read_ptr		\
174 			 >= (_fp)->_wide_data->_IO_read_end))		\
175    ? __wuflow (_fp) : (wint_t) *(_fp)->_wide_data->_IO_read_ptr++)
176 # define _IO_putwc_unlocked(_wch, _fp)					\
177   (__glibc_unlikely ((_fp)->_wide_data == NULL				\
178 		     || ((_fp)->_wide_data->_IO_write_ptr		\
179 			 >= (_fp)->_wide_data->_IO_write_end))		\
180    ? __woverflow (_fp, _wch)						\
181    : (wint_t) (*(_fp)->_wide_data->_IO_write_ptr++ = (_wch)))
182 
183 #define _IO_feof_unlocked(_fp) __feof_unlocked_body (_fp)
184 #define _IO_ferror_unlocked(_fp) __ferror_unlocked_body (_fp)
185 
186 extern int _IO_getc (FILE *__fp);
187 extern int _IO_putc (int __c, FILE *__fp);
188 extern int _IO_feof (FILE *__fp) __THROW;
189 extern int _IO_ferror (FILE *__fp) __THROW;
190 
191 extern int _IO_peekc_locked (FILE *__fp);
192 
193 /* This one is for Emacs. */
194 #define _IO_PENDING_OUTPUT_COUNT(_fp)	\
195 	((_fp)->_IO_write_ptr - (_fp)->_IO_write_base)
196 
197 extern void _IO_flockfile (FILE *) __THROW;
198 extern void _IO_funlockfile (FILE *) __THROW;
199 extern int _IO_ftrylockfile (FILE *) __THROW;
200 
201 #define _IO_peekc(_fp) _IO_peekc_unlocked (_fp)
202 #define _IO_flockfile(_fp) /**/
203 #define _IO_funlockfile(_fp) ((void) 0)
204 #define _IO_ftrylockfile(_fp) /**/
205 #ifndef _IO_cleanup_region_start
206 #define _IO_cleanup_region_start(_fct, _fp) /**/
207 #endif
208 #ifndef _IO_cleanup_region_end
209 #define _IO_cleanup_region_end(_Doit) /**/
210 #endif
211 
212 #define _IO_need_lock(_fp) \
213   (((_fp)->_flags2 & _IO_FLAGS2_NEED_LOCK) != 0)
214 
215 extern int _IO_vfscanf (FILE * __restrict, const char * __restrict,
216 			__gnuc_va_list, int *__restrict);
217 extern __ssize_t _IO_padn (FILE *, int, __ssize_t);
218 extern size_t _IO_sgetn (FILE *, void *, size_t);
219 
220 extern off64_t _IO_seekoff (FILE *, off64_t, int, int);
221 extern off64_t _IO_seekpos (FILE *, off64_t, int);
222 
223 extern void _IO_free_backup_area (FILE *) __THROW;
224 
225 
226 extern wint_t _IO_getwc (FILE *__fp);
227 extern wint_t _IO_putwc (wchar_t __wc, FILE *__fp);
228 extern int _IO_fwide (FILE *__fp, int __mode) __THROW;
229 
230 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
231 #  define _IO_fwide_maybe_incompatible \
232   (__glibc_unlikely (&_IO_stdin_used == NULL))
233 extern const int _IO_stdin_used;
234 weak_extern (_IO_stdin_used);
235 #else
236 # define _IO_fwide_maybe_incompatible (0)
237 #endif
238 
239 /* A special optimized version of the function above.  It optimizes the
240    case of initializing an unoriented byte stream.  */
241 #define _IO_fwide(__fp, __mode) \
242   ({ int __result = (__mode);						      \
243      if (__result < 0 && ! _IO_fwide_maybe_incompatible)		      \
244        {								      \
245 	 if ((__fp)->_mode == 0)					      \
246 	   /* We know that all we have to do is to set the flag.  */	      \
247 	   (__fp)->_mode = -1;						      \
248 	 __result = (__fp)->_mode;					      \
249        }								      \
250      else if (__builtin_constant_p (__mode) && (__mode) == 0)		      \
251        __result = _IO_fwide_maybe_incompatible ? -1 : (__fp)->_mode;	      \
252      else								      \
253        __result = _IO_fwide (__fp, __result);				      \
254      __result; })
255 
256 extern __ssize_t _IO_wpadn (FILE *, wint_t, __ssize_t);
257 extern void _IO_free_wbackup_area (FILE *) __THROW;
258 
259 #ifdef __LDBL_COMPAT
260 __LDBL_REDIR_DECL (_IO_vfscanf)
261 #endif
262 
263 libc_hidden_proto (__overflow)
264 libc_hidden_proto (__underflow)
265 libc_hidden_proto (__uflow)
266 libc_hidden_proto (__woverflow)
267 libc_hidden_proto (__wunderflow)
268 libc_hidden_proto (__wuflow)
269 libc_hidden_proto (_IO_free_backup_area)
270 libc_hidden_proto (_IO_free_wbackup_area)
271 libc_hidden_proto (_IO_padn)
272 libc_hidden_proto (_IO_putc)
273 libc_hidden_proto (_IO_sgetn)
274 
275 #ifdef _IO_MTSAFE_IO
276 # undef _IO_peekc
277 # undef _IO_flockfile
278 # undef _IO_funlockfile
279 # undef _IO_ftrylockfile
280 
281 # define _IO_peekc(_fp) _IO_peekc_locked (_fp)
282 # define _IO_flockfile(_fp) \
283   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_lock_lock (*(_fp)->_lock)
284 # define _IO_funlockfile(_fp) \
285   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_lock_unlock (*(_fp)->_lock)
286 #endif /* _IO_MTSAFE_IO */
287 
288 #endif /* _LIBIO_H */
289