libio/strfile.h

   1 /* Copyright (C) 1993-2018 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    <http://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 #include <stdio.h>
  28 #include "libioP.h"
  29
  30 typedef void *(*_IO_alloc_type) (size_t);
  31 typedef void (*_IO_free_type) (void*);
  32
  33 struct _IO_str_fields
  34 {
  35   _IO_alloc_type _allocate_buffer;
  36   _IO_free_type _free_buffer;
  37 };
  38
  39 /* This is needed for the Irix6 N32 ABI, which has a 64 bit off_t type,
  40    but a 32 bit pointer type.  In this case, we get 4 bytes of padding
  41    after the vtable pointer.  Putting them in a structure together solves
  42    this problem.  */
  43
  44 struct _IO_streambuf
  45 {
  46   FILE _f;
  47   const struct _IO_jump_t *vtable;
  48 };
  49
  50 typedef struct _IO_strfile_
  51 {
  52   struct _IO_streambuf _sbf;
  53   struct _IO_str_fields _s;
  54 } _IO_strfile;
  55
  56 /* dynamic: set when the array object is allocated (or reallocated)  as
  57    necessary to hold a character sequence that can change in length. */
  58 #define _IO_STR_DYNAMIC(FP) ((FP)->_s._allocate_buffer != (_IO_alloc_type)0)
  59
  60 /* frozen: set when the program has requested that the array object not
  61    be altered, reallocated, or freed. */
  62 #define _IO_STR_FROZEN(FP) ((FP)->_f._flags & _IO_USER_BUF)
  63
  64 typedef struct
  65 {
  66   _IO_strfile f;
  67   /* This is used for the characters which do not fit in the buffer
  68      provided by the user.  */
  69   char overflow_buf[64];
  70 } _IO_strnfile;
  71
  72 extern const struct _IO_jump_t _IO_strn_jumps attribute_hidden;
  73
  74
  75 typedef struct
  76 {
  77   _IO_strfile f;
  78   /* This is used for the characters which do not fit in the buffer
  79      provided by the user.  */
  80   wchar_t overflow_buf[64];
  81 } _IO_wstrnfile;
  82
  83 extern const struct _IO_jump_t _IO_wstrn_jumps attribute_hidden;