lib/stdio-impl.h

   1 /* Implementation details of FILE streams.
   2    Copyright (C) 2007-2008, 2010-2017 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Many stdio implementations have the same logic and therefore can share
  18    the same implementation of stdio extension API, except that some fields
  19    have different naming conventions, or their access requires some casts.  */
  20
  21
  22 /* BSD stdio derived implementations.  */
  23
  24 #if defined __NetBSD__                         /* NetBSD */
  25 /* Get __NetBSD_Version__.  */
  26 # include <sys/param.h>
  27 #endif
  28
  29 #include <errno.h>                             /* For detecting Plan9.  */
  30
  31 #if defined __sferror || defined __DragonFly__ || defined __ANDROID__
  32   /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */
  33
  34 # if defined __DragonFly__          /* DragonFly */
  35   /* See <https://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/lib/libc/stdio/priv_stdio.h>.  */
  36 #  define fp_ ((struct { struct __FILE_public pub; \
  37                          struct { unsigned char *_base; int _size; } _bf; \
  38                          void *cookie; \
  39                          void *_close; \
  40                          void *_read; \
  41                          void *_seek; \
  42                          void *_write; \
  43                          struct { unsigned char *_base; int _size; } _ub; \
  44                          int _ur; \
  45                          unsigned char _ubuf[3]; \
  46                          unsigned char _nbuf[1]; \
  47                          struct { unsigned char *_base; int _size; } _lb; \
  48                          int _blksize; \
  49                          fpos_t _offset; \
  50                          /* More fields, not relevant here.  */ \
  51                        } *) fp)
  52   /* See <https://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/include/stdio.h>.  */
  53 #  define _p pub._p
  54 #  define _flags pub._flags
  55 #  define _r pub._r
  56 #  define _w pub._w
  57 # else
  58 #  define fp_ fp
  59 # endif
  60
  61 # if (defined __NetBSD__ && __NetBSD_Version__ >= 105270000) || defined __OpenBSD__ || defined __minix || defined __ANDROID__ /* NetBSD >= 1.5ZA, OpenBSD, Minix 3, Android */
  62   /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
  63      and <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */
  64   struct __sfileext
  65     {
  66       struct  __sbuf _ub; /* ungetc buffer */
  67       /* More fields, not relevant here.  */
  68     };
  69 #  define fp_ub ((struct __sfileext *) fp->_ext._base)->_ub
  70 # else                                         /* FreeBSD, NetBSD <= 1.5Z, DragonFly, Mac OS X, Cygwin, Android */
  71 #  define fp_ub fp_->_ub
  72 # endif
  73
  74 # define HASUB(fp) (fp_ub._base != NULL)
  75
  76 #endif
  77
  78
  79 /* SystemV derived implementations.  */
  80
  81 #ifdef __TANDEM                     /* NonStop Kernel */
  82 # ifndef _IOERR
  83 /* These values were determined by the program 'stdioext-flags' at
  84    <https://lists.gnu.org/archive/html/bug-gnulib/2010-12/msg00165.html>.  */
  85 #  define _IOERR   0x40
  86 #  define _IOREAD  0x80
  87 #  define _IOWRT    0x4
  88 #  define _IORW   0x100
  89 # endif
  90 #endif
  91
  92 #if defined _IOERR
  93
  94 # if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */
  95 #  define fp_ ((struct { unsigned char *_ptr; \
  96                          unsigned char *_base; \
  97                          unsigned char *_end; \
  98                          long _cnt; \
  99                          int _file; \
 100                          unsigned int _flag; \
 101                        } *) fp)
 102 # elif defined __VMS                /* OpenVMS */
 103 #  define fp_ ((struct _iobuf *) fp)
 104 # else
 105 #  define fp_ fp
 106 # endif
 107
 108 # if defined _SCO_DS                /* OpenServer */
 109 #  define _cnt __cnt
 110 #  define _ptr __ptr
 111 #  define _base __base
 112 #  define _flag __flag
 113 # endif
 114
 115 #elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__  /* newer Windows with MSVC */
 116
 117 /* <stdio.h> does not define the innards of FILE any more.  */
 118 # define WINDOWS_OPAQUE_FILE
 119
 120 struct _gl_real_FILE
 121 {
 122   /* Note: Compared to older Windows and to mingw, it has the fields
 123      _base and _cnt swapped. */
 124   unsigned char *_ptr;
 125   unsigned char *_base;
 126   int _cnt;
 127   int _flag;
 128   int _file;
 129   int _charbuf;
 130   int _bufsiz;
 131 };
 132 # define fp_ ((struct _gl_real_FILE *) fp)
 133
 134 /* These values were determined by a program similar to the one at
 135    <https://lists.gnu.org/archive/html/bug-gnulib/2010-12/msg00165.html>.  */
 136 # define _IOREAD   0x1
 137 # define _IOWRT    0x2
 138 # define _IORW     0x4
 139 # define _IOEOF    0x8
 140 # define _IOERR   0x10
 141
 142 #endif