gl/stdio-impl.h

   1 /* Implementation details of FILE streams.
   2    Copyright (C) 2007-2008, 2010-2023 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file 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 Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser 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 /* Glibc 2.28 made _IO_UNBUFFERED and _IO_IN_BACKUP private.  For now, work
  22    around this problem by defining them ourselves.  FIXME: Do not rely on glibc
  23    internals.  */
  24 #if defined _IO_EOF_SEEN
  25 # if !defined _IO_UNBUFFERED
  26 #  define _IO_UNBUFFERED 0x2
  27 # endif
  28 # if !defined _IO_IN_BACKUP
  29 #  define _IO_IN_BACKUP 0x100
  30 # endif
  31 #endif
  32
  33 /* BSD stdio derived implementations.  */
  34
  35 #if defined __NetBSD__                         /* NetBSD */
  36 /* Get __NetBSD_Version__.  */
  37 # include <sys/param.h>
  38 #endif
  39
  40 #include <errno.h>                             /* For detecting Plan9.  */
  41
  42 #if defined __sferror || defined __DragonFly__ || defined __ANDROID__
  43   /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */
  44
  45 # if defined __DragonFly__          /* DragonFly */
  46   /* See <https://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/lib/libc/stdio/priv_stdio.h>.  */
  47 #  define fp_ ((struct { struct __FILE_public pub; \
  48                          struct { unsigned char *_base; int _size; } _bf; \
  49                          void *cookie; \
  50                          void *_close; \
  51                          void *_read; \
  52                          void *_seek; \
  53                          void *_write; \
  54                          struct { unsigned char *_base; int _size; } _ub; \
  55                          int _ur; \
  56                          unsigned char _ubuf[3]; \
  57                          unsigned char _nbuf[1]; \
  58                          struct { unsigned char *_base; int _size; } _lb; \
  59                          int _blksize; \
  60                          fpos_t _offset; \
  61                          /* More fields, not relevant here.  */ \
  62                        } *) fp)
  63   /* See <https://gitweb.dragonflybsd.org/dragonfly.git/blob_plain/HEAD:/include/stdio.h>.  */
  64 #  define _p pub._p
  65 #  define _flags pub._flags
  66 #  define _r pub._r
  67 #  define _w pub._w
  68 # elif defined __ANDROID__ /* Android */
  69 #  ifdef __LP64__
  70 #   define _gl_flags_file_t int
  71 #  else
  72 #   define _gl_flags_file_t short
  73 #  endif
  74 #  ifdef __LP64__
  75 #   define _gl_file_offset_t int64_t
  76 #  else
  77     /* see https://android.googlesource.com/platform/bionic/+/master/docs/32-bit-abi.md */
  78 #   define _gl_file_offset_t __kernel_off_t
  79 #  endif
  80   /* Up to this commit from 2015-10-12
  81      <https://android.googlesource.com/platform/bionic.git/+/f0141dfab10a4b332769d52fa76631a64741297a>
  82      the innards of FILE were public, and fp_ub could be defined like for OpenBSD,
  83      see <https://android.googlesource.com/platform/bionic.git/+/e78392637d5086384a5631ddfdfa8d7ec8326ee3/libc/stdio/fileext.h>
  84      and <https://android.googlesource.com/platform/bionic.git/+/e78392637d5086384a5631ddfdfa8d7ec8326ee3/libc/stdio/local.h>.
  85      After this commit, the innards of FILE are hidden.  */
  86 #  define fp_ ((struct { unsigned char *_p; \
  87                          int _r; \
  88                          int _w; \
  89                          _gl_flags_file_t _flags; \
  90                          _gl_flags_file_t _file; \
  91                          struct { unsigned char *_base; size_t _size; } _bf; \
  92                          int _lbfsize; \
  93                          void *_cookie; \
  94                          void *_close; \
  95                          void *_read; \
  96                          void *_seek; \
  97                          void *_write; \
  98                          struct { unsigned char *_base; size_t _size; } _ext; \
  99                          unsigned char *_up; \
 100                          int _ur; \
 101                          unsigned char _ubuf[3]; \
 102                          unsigned char _nbuf[1]; \
 103                          struct { unsigned char *_base; size_t _size; } _lb; \
 104                          int _blksize; \
 105                          _gl_file_offset_t _offset; \
 106                          /* More fields, not relevant here.  */ \
 107                        } *) fp)
 108 # else
 109 #  define fp_ fp
 110 # endif
 111
 112 # if (defined __NetBSD__ && __NetBSD_Version__ >= 105270000) || defined __OpenBSD__ || defined __minix /* NetBSD >= 1.5ZA, OpenBSD, Minix 3 */
 113   /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
 114      and <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
 115      and <https://github.com/Stichting-MINIX-Research-Foundation/minix/blob/master/lib/libc/stdio/fileext.h> */
 116   struct __sfileext
 117     {
 118       struct  __sbuf _ub; /* ungetc buffer */
 119       /* More fields, not relevant here.  */
 120     };
 121 #  define fp_ub ((struct __sfileext *) fp->_ext._base)->_ub
 122 # elif defined __ANDROID__                     /* Android */
 123   struct __sfileext
 124     {
 125       struct { unsigned char *_base; size_t _size; } _ub; /* ungetc buffer */
 126       /* More fields, not relevant here.  */
 127     };
 128 #  define fp_ub ((struct __sfileext *) fp_->_ext._base)->_ub
 129 # else                                         /* FreeBSD, NetBSD <= 1.5Z, DragonFly, Mac OS X, Cygwin */
 130 #  define fp_ub fp_->_ub
 131 # endif
 132
 133 # define HASUB(fp) (fp_ub._base != NULL)
 134
 135 # if defined __ANDROID__ /* Android */
 136   /* Needed after this commit from 2016-01-25
 137      <https://android.googlesource.com/platform/bionic.git/+/e70e0e9267d069bf56a5078c99307e08a7280de7> */
 138 #  ifndef __SEOF
 139 #   define __SLBF 1
 140 #   define __SNBF 2
 141 #   define __SRD 4
 142 #   define __SWR 8
 143 #   define __SRW 0x10
 144 #   define __SEOF 0x20
 145 #   define __SERR 0x40
 146 #  endif
 147 #  ifndef __SOFF
 148 #   define __SOFF 0x1000
 149 #  endif
 150 # endif
 151
 152 #endif
 153
 154
 155 /* SystemV derived implementations.  */
 156
 157 #ifdef __TANDEM                     /* NonStop Kernel */
 158 # ifndef _IOERR
 159 /* These values were determined by the program 'stdioext-flags' at
 160    <https://lists.gnu.org/r/bug-gnulib/2010-12/msg00165.html>.  */
 161 #  define _IOERR   0x40
 162 #  define _IOREAD  0x80
 163 #  define _IOWRT    0x4
 164 #  define _IORW   0x100
 165 # endif
 166 #endif
 167
 168 #if defined _IOERR
 169
 170 # if defined __sun && defined _LP64 /* Solaris/{SPARC,AMD64} 64-bit */
 171 #  define fp_ ((struct { unsigned char *_ptr; \
 172                          unsigned char *_base; \
 173                          unsigned char *_end; \
 174                          long _cnt; \
 175                          int _file; \
 176                          unsigned int _flag; \
 177                        } *) fp)
 178 # elif defined __VMS                /* OpenVMS */
 179 #  define fp_ ((struct _iobuf *) fp)
 180 # else
 181 #  define fp_ fp
 182 # endif
 183
 184 # if defined _SCO_DS || (defined __SCO_VERSION__ || defined __sysv5__)  /* OpenServer 5, OpenServer 6, UnixWare 7 */
 185 #  define _cnt __cnt
 186 #  define _ptr __ptr
 187 #  define _base __base
 188 #  define _flag __flag
 189 # endif
 190
 191 #elif defined _WIN32 && ! defined __CYGWIN__  /* newer Windows with MSVC */
 192
 193 /* <stdio.h> does not define the innards of FILE any more.  */
 194 # define WINDOWS_OPAQUE_FILE
 195
 196 struct _gl_real_FILE
 197 {
 198   /* Note: Compared to older Windows and to mingw, it has the fields
 199      _base and _cnt swapped. */
 200   unsigned char *_ptr;
 201   unsigned char *_base;
 202   int _cnt;
 203   int _flag;
 204   int _file;
 205   int _charbuf;
 206   int _bufsiz;
 207 };
 208 # define fp_ ((struct _gl_real_FILE *) fp)
 209
 210 /* These values were determined by a program similar to the one at
 211    <https://lists.gnu.org/r/bug-gnulib/2010-12/msg00165.html>.  */
 212 # define _IOREAD   0x1
 213 # define _IOWRT    0x2
 214 # define _IORW     0x4
 215 # define _IOEOF    0x8
 216 # define _IOERR   0x10
 217
 218 #endif