libio/libio.h

   1 /* Copyright (C) 1991-2018 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Written by Per Bothner <bothner@cygnus.com>.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.
  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 #ifndef _LIBIO_H
  29 #define _LIBIO_H 1
  30
  31 #ifndef _LIBC
  32 # error "libio.h should only be included when building glibc itself"
  33 #endif
  34 #ifdef _ISOMAC
  35 # error "libio.h should not be included under _ISOMAC"
  36 #endif
  37
  38 #include <stdio.h>
  39
  40 #if defined _IO_MTSAFE_IO && !defined _IO_lock_t_defined
  41 # error "Someone forgot to include stdio-lock.h"
  42 #endif
  43
  44 #define __need_wchar_t
  45 #include <stddef.h>
  46
  47 #include <bits/types/__mbstate_t.h>
  48 #include <bits/types/wint_t.h>
  49 #include <gconv.h>
  50
  51 typedef union
  52 {
  53   struct __gconv_info __cd;
  54   struct
  55   {
  56     struct __gconv_info __cd;
  57     struct __gconv_step_data __data;
  58   } __combined;
  59 } _IO_iconv_t;
  60
  61 #include <shlib-compat.h>
  62
  63 /* _IO_seekoff modes */
  64 #define _IOS_INPUT      1
  65 #define _IOS_OUTPUT     2
  66
  67 /* Magic number and bits for the _flags field.  The magic number is
  68    mostly vestigial, but preserved for compatibility.  It occupies the
  69    high 16 bits of _flags; the low 16 bits are actual flag bits.  */
  70
  71 #define _IO_MAGIC         0xFBAD0000 /* Magic number */
  72 #define _IO_MAGIC_MASK    0xFFFF0000
  73 #define _IO_USER_BUF          0x0001 /* Don't deallocate buffer on close. */
  74 #define _IO_UNBUFFERED        0x0002
  75 #define _IO_NO_READS          0x0004 /* Reading not allowed.  */
  76 #define _IO_NO_WRITES         0x0008 /* Writing not allowed.  */
  77 #define _IO_EOF_SEEN          0x0010
  78 #define _IO_ERR_SEEN          0x0020
  79 #define _IO_DELETE_DONT_CLOSE 0x0040 /* Don't call close(_fileno) on close.  */
  80 #define _IO_LINKED            0x0080 /* In the list of all open files.  */
  81 #define _IO_IN_BACKUP         0x0100
  82 #define _IO_LINE_BUF          0x0200
  83 #define _IO_TIED_PUT_GET      0x0400 /* Put and get pointer move in unison.  */
  84 #define _IO_CURRENTLY_PUTTING 0x0800
  85 #define _IO_IS_APPENDING      0x1000
  86 #define _IO_IS_FILEBUF        0x2000
  87                            /* 0x4000  No longer used, reserved for compat.  */
  88 #define _IO_USER_LOCK         0x8000
  89
  90 /* Bits for the _flags2 field.  */
  91 #define _IO_FLAGS2_MMAP 1
  92 #define _IO_FLAGS2_NOTCANCEL 2
  93 #define _IO_FLAGS2_FORTIFY 4
  94 #define _IO_FLAGS2_USER_WBUF 8
  95 #define _IO_FLAGS2_SCANF_STD 16
  96 #define _IO_FLAGS2_NOCLOSE 32
  97 #define _IO_FLAGS2_CLOEXEC 64
  98 #define _IO_FLAGS2_NEED_LOCK 128
  99
 100 /* _IO_pos_BAD is an off64_t value indicating error, unknown, or EOF.  */
 101 #define _IO_pos_BAD ((off64_t) -1)
 102
 103 /* _IO_pos_adjust adjusts an off64_t by some number of bytes.  */
 104 #define _IO_pos_adjust(pos, delta) ((pos) += (delta))
 105
 106 /* _IO_pos_0 is an off64_t value indicating beginning of file.  */
 107 #define _IO_pos_0 ((off64_t) 0)
 108
 109 struct _IO_jump_t;
 110
 111 /* A streammarker remembers a position in a buffer. */
 112 struct _IO_marker {
 113   struct _IO_marker *_next;
 114   FILE *_sbuf;
 115   /* If _pos >= 0
 116  it points to _buf->Gbase()+_pos. FIXME comment */
 117   /* if _pos < 0, it points to _buf->eBptr()+_pos. FIXME comment */
 118   int _pos;
 119 };
 120
 121 /* This is the structure from the libstdc++ codecvt class.  */
 122 enum __codecvt_result
 123 {
 124   __codecvt_ok,
 125   __codecvt_partial,
 126   __codecvt_error,
 127   __codecvt_noconv
 128 };
 129
 130 /* The order of the elements in the following struct must match the order
 131    of the virtual functions in the libstdc++ codecvt class.  */
 132 struct _IO_codecvt
 133 {
 134   void (*__codecvt_destr) (struct _IO_codecvt *);
 135   enum __codecvt_result (*__codecvt_do_out) (struct _IO_codecvt *,
 136                                              __mbstate_t *,
 137                                              const wchar_t *,
 138                                              const wchar_t *,
 139                                              const wchar_t **, char *,
 140                                              char *, char **);
 141   enum __codecvt_result (*__codecvt_do_unshift) (struct _IO_codecvt *,
 142                                                  __mbstate_t *, char *,
 143                                                  char *, char **);
 144   enum __codecvt_result (*__codecvt_do_in) (struct _IO_codecvt *,
 145                                             __mbstate_t *,
 146                                             const char *, const char *,
 147                                             const char **, wchar_t *,
 148                                             wchar_t *, wchar_t **);
 149   int (*__codecvt_do_encoding) (struct _IO_codecvt *);
 150   int (*__codecvt_do_always_noconv) (struct _IO_codecvt *);
 151   int (*__codecvt_do_length) (struct _IO_codecvt *, __mbstate_t *,
 152                               const char *, const char *, size_t);
 153   int (*__codecvt_do_max_length) (struct _IO_codecvt *);
 154
 155   _IO_iconv_t __cd_in;
 156   _IO_iconv_t __cd_out;
 157 };
 158
 159 /* Extra data for wide character streams.  */
 160 struct _IO_wide_data
 161 {
 162   wchar_t *_IO_read_ptr;        /* Current read pointer */
 163   wchar_t *_IO_read_end;        /* End of get area. */
 164   wchar_t *_IO_read_base;       /* Start of putback+get area. */
 165   wchar_t *_IO_write_base;      /* Start of put area. */
 166   wchar_t *_IO_write_ptr;       /* Current put pointer. */
 167   wchar_t *_IO_write_end;       /* End of put area. */
 168   wchar_t *_IO_buf_base;        /* Start of reserve area. */
 169   wchar_t *_IO_buf_end;         /* End of reserve area. */
 170   /* The following fields are used to support backing up and undo. */
 171   wchar_t *_IO_save_base;       /* Pointer to start of non-current get area. */
 172   wchar_t *_IO_backup_base;     /* Pointer to first valid character of
 173                                    backup area */
 174   wchar_t *_IO_save_end;        /* Pointer to end of non-current get area. */
 175
 176   __mbstate_t _IO_state;
 177   __mbstate_t _IO_last_state;
 178   struct _IO_codecvt _codecvt;
 179
 180   wchar_t _shortbuf[1];
 181
 182   const struct _IO_jump_t *_wide_vtable;
 183 };
 184
 185 struct _IO_FILE_plus;
 186
 187 extern struct _IO_FILE_plus _IO_2_1_stdin_;
 188 extern struct _IO_FILE_plus _IO_2_1_stdout_;
 189 extern struct _IO_FILE_plus _IO_2_1_stderr_;
 190 extern FILE *_IO_stdin attribute_hidden;
 191 extern FILE *_IO_stdout attribute_hidden;
 192 extern FILE *_IO_stderr attribute_hidden;
 193
 194 struct _IO_cookie_file;
 195
 196 /* Initialize one of those.  */
 197 extern void _IO_cookie_init (struct _IO_cookie_file *__cfile, int __read_write,
 198                              void *__cookie, cookie_io_functions_t __fns);
 199
 200 extern int __underflow (FILE *);
 201 extern wint_t __wunderflow (FILE *);
 202 extern wint_t __wuflow (FILE *);
 203 extern wint_t __woverflow (FILE *, wint_t);
 204
 205 #define _IO_getc_unlocked(_fp) __getc_unlocked_body (_fp)
 206 #define _IO_peekc_unlocked(_fp)                                         \
 207   (__glibc_unlikely ((_fp)->_IO_read_ptr >= (_fp)->_IO_read_end)        \
 208    && __underflow (_fp) == EOF                                          \
 209    ? EOF                                                                \
 210    : *(unsigned char *) (_fp)->_IO_read_ptr)
 211 #define _IO_putc_unlocked(_ch, _fp) __putc_unlocked_body (_ch, _fp)
 212
 213 # define _IO_getwc_unlocked(_fp)                                        \
 214   (__glibc_unlikely ((_fp)->_wide_data == NULL                          \
 215                      || ((_fp)->_wide_data->_IO_read_ptr                \
 216                          >= (_fp)->_wide_data->_IO_read_end))           \
 217    ? __wuflow (_fp) : (wint_t) *(_fp)->_wide_data->_IO_read_ptr++)
 218 # define _IO_putwc_unlocked(_wch, _fp)                                  \
 219   (__glibc_unlikely ((_fp)->_wide_data == NULL                          \
 220                      || ((_fp)->_wide_data->_IO_write_ptr               \
 221                          >= (_fp)->_wide_data->_IO_write_end))          \
 222    ? __woverflow (_fp, _wch)                                            \
 223    : (wint_t) (*(_fp)->_wide_data->_IO_write_ptr++ = (_wch)))
 224
 225 #define _IO_feof_unlocked(_fp) __feof_unlocked_body (_fp)
 226 #define _IO_ferror_unlocked(_fp) __ferror_unlocked_body (_fp)
 227
 228 extern int _IO_getc (FILE *__fp);
 229 extern int _IO_putc (int __c, FILE *__fp);
 230 extern int _IO_feof (FILE *__fp) __THROW;
 231 extern int _IO_ferror (FILE *__fp) __THROW;
 232
 233 extern int _IO_peekc_locked (FILE *__fp);
 234
 235 /* This one is for Emacs. */
 236 #define _IO_PENDING_OUTPUT_COUNT(_fp)   \
 237         ((_fp)->_IO_write_ptr - (_fp)->_IO_write_base)
 238
 239 extern void _IO_flockfile (FILE *) __THROW;
 240 extern void _IO_funlockfile (FILE *) __THROW;
 241 extern int _IO_ftrylockfile (FILE *) __THROW;
 242
 243 #define _IO_peekc(_fp) _IO_peekc_unlocked (_fp)
 244 #define _IO_flockfile(_fp) /**/
 245 #define _IO_funlockfile(_fp) /**/
 246 #define _IO_ftrylockfile(_fp) /**/
 247 #ifndef _IO_cleanup_region_start
 248 #define _IO_cleanup_region_start(_fct, _fp) /**/
 249 #endif
 250 #ifndef _IO_cleanup_region_end
 251 #define _IO_cleanup_region_end(_Doit) /**/
 252 #endif
 253
 254 #define _IO_need_lock(_fp) \
 255   (((_fp)->_flags2 & _IO_FLAGS2_NEED_LOCK) != 0)
 256
 257 extern int _IO_vfscanf (FILE * __restrict, const char * __restrict,
 258                         __gnuc_va_list, int *__restrict);
 259 extern int _IO_vfprintf (FILE *__restrict, const char *__restrict,
 260                          __gnuc_va_list);
 261 extern __ssize_t _IO_padn (FILE *, int, __ssize_t);
 262 extern size_t _IO_sgetn (FILE *, void *, size_t);
 263
 264 extern off64_t _IO_seekoff (FILE *, off64_t, int, int);
 265 extern off64_t _IO_seekpos (FILE *, off64_t, int);
 266
 267 extern void _IO_free_backup_area (FILE *) __THROW;
 268
 269
 270 extern wint_t _IO_getwc (FILE *__fp);
 271 extern wint_t _IO_putwc (wchar_t __wc, FILE *__fp);
 272 extern int _IO_fwide (FILE *__fp, int __mode) __THROW;
 273
 274 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
 275 #  define _IO_fwide_maybe_incompatible \
 276   (__glibc_unlikely (&_IO_stdin_used == NULL))
 277 extern const int _IO_stdin_used;
 278 weak_extern (_IO_stdin_used);
 279 #else
 280 # define _IO_fwide_maybe_incompatible (0)
 281 #endif
 282
 283 /* A special optimized version of the function above.  It optimizes the
 284    case of initializing an unoriented byte stream.  */
 285 #define _IO_fwide(__fp, __mode) \
 286   ({ int __result = (__mode);                                                 \
 287      if (__result < 0 && ! _IO_fwide_maybe_incompatible)                      \
 288        {                                                                      \
 289          if ((__fp)->_mode == 0)                                              \
 290            /* We know that all we have to do is to set the flag.  */          \
 291            (__fp)->_mode = -1;                                                \
 292          __result = (__fp)->_mode;                                            \
 293        }                                                                      \
 294      else if (__builtin_constant_p (__mode) && (__mode) == 0)                 \
 295        __result = _IO_fwide_maybe_incompatible ? -1 : (__fp)->_mode;          \
 296      else                                                                     \
 297        __result = _IO_fwide (__fp, __result);                                 \
 298      __result; })
 299
 300 extern int _IO_vfwscanf (FILE * __restrict, const wchar_t * __restrict,
 301                          __gnuc_va_list, int *__restrict);
 302 extern int _IO_vfwprintf (FILE *__restrict, const wchar_t *__restrict,
 303                           __gnuc_va_list);
 304 extern __ssize_t _IO_wpadn (FILE *, wint_t, __ssize_t);
 305 extern void _IO_free_wbackup_area (FILE *) __THROW;
 306
 307 #ifdef __LDBL_COMPAT
 308 __LDBL_REDIR_DECL (_IO_vfscanf)
 309 __LDBL_REDIR_DECL (_IO_vfprintf)
 310 #endif
 311
 312 libc_hidden_proto (__overflow)
 313 libc_hidden_proto (__underflow)
 314 libc_hidden_proto (__uflow)
 315 libc_hidden_proto (__woverflow)
 316 libc_hidden_proto (__wunderflow)
 317 libc_hidden_proto (__wuflow)
 318 libc_hidden_proto (_IO_free_backup_area)
 319 libc_hidden_proto (_IO_free_wbackup_area)
 320 libc_hidden_proto (_IO_padn)
 321 libc_hidden_proto (_IO_putc)
 322 libc_hidden_proto (_IO_sgetn)
 323 libc_hidden_proto (_IO_vfprintf)
 324 libc_hidden_proto (_IO_vfscanf)
 325
 326 #ifdef _IO_MTSAFE_IO
 327 # undef _IO_peekc
 328 # undef _IO_flockfile
 329 # undef _IO_funlockfile
 330 # undef _IO_ftrylockfile
 331
 332 # define _IO_peekc(_fp) _IO_peekc_locked (_fp)
 333 # if _IO_lock_inexpensive
 334 #  define _IO_flockfile(_fp) \
 335   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_lock_lock (*(_fp)->_lock)
 336 #  define _IO_funlockfile(_fp) \
 337   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_lock_unlock (*(_fp)->_lock)
 338 # else
 339 #  define _IO_flockfile(_fp) \
 340   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_flockfile (_fp)
 341 #  define _IO_funlockfile(_fp) \
 342   if (((_fp)->_flags & _IO_USER_LOCK) == 0) _IO_funlockfile (_fp)
 343 # endif
 344 #endif /* _IO_MTSAFE_IO */
 345
 346 #endif /* _LIBIO_H */