gcc/ada/cstreams.c

   1 /****************************************************************************
   2  *                                                                          *
   3  *                          GNAT RUN-TIME COMPONENTS                        *
   4  *                                                                          *
   5  *                              C S T R E A M S                             *
   6  *                                                                          *
   7  *              Auxiliary C functions for Interfaces.C.Streams              *
   8  *                                                                          *
   9  *          Copyright (C) 1992-2023, Free Software Foundation, Inc.         *
  10  *                                                                          *
  11  * GNAT is free software;  you can  redistribute it  and/or modify it under *
  12  * terms of the  GNU General Public License as published  by the Free Soft- *
  13  * ware  Foundation;  either version 3,  or (at your option) any later ver- *
  14  * sion.  GNAT is distributed in the hope that it will be useful, but WITH- *
  15  * OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY *
  16  * or FITNESS FOR A PARTICULAR PURPOSE.                                     *
  17  *                                                                          *
  18  * As a special exception under Section 7 of GPL version 3, you are granted *
  19  * additional permissions described in the GCC Runtime Library Exception,   *
  20  * version 3.1, as published by the Free Software Foundation.               *
  21  *                                                                          *
  22  * You should have received a copy of the GNU General Public License and    *
  23  * a copy of the GCC Runtime Library Exception along with this program;     *
  24  * see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    *
  25  * <http://www.gnu.org/licenses/>.                                          *
  26  *                                                                          *
  27  * GNAT was originally developed  by the GNAT team at  New York University. *
  28  * Extensive contributions were provided by Ada Core Technologies Inc.      *
  29  *                                                                          *
  30  ****************************************************************************/
  31
  32 /* Routines required for implementing routines in Interfaces.C.Streams.  */
  33
  34 #ifndef _LARGEFILE_SOURCE
  35 #define _LARGEFILE_SOURCE
  36 #endif
  37 #define _FILE_OFFSET_BITS 64
  38 /* the define above will make off_t a 64bit type on GNU/Linux */
  39
  40 /* Tell Cygwin's <stdio.h> to expose fileno_unlocked() */
  41 #if defined(__CYGWIN__) && !defined(__CYGWIN32__) && !defined(_GNU_SOURCE)
  42 #define _GNU_SOURCE
  43 #endif
  44
  45 #include <stdio.h>
  46 #include <sys/types.h>
  47 #include <sys/stat.h>
  48 #include <unistd.h>
  49 #include <stdlib.h>
  50
  51 #ifdef _AIX
  52 /* needed to avoid conflicting declarations */
  53 #include <unistd.h>
  54 #include <sys/mman.h>
  55 #endif
  56
  57 #ifdef __vxworks
  58 #include "vxWorks.h"
  59 #endif
  60
  61 #ifdef IN_RTS
  62 #include <string.h>
  63 #else
  64 #include "config.h"
  65 #include "system.h"
  66 #endif
  67
  68 #include "adaint.h"
  69
  70 #ifdef __cplusplus
  71 extern "C" {
  72 #endif
  73
  74 #ifdef __linux__
  75 /* Don't use macros on GNU/Linux since they cause incompatible changes between
  76    glibc 2.0 and 2.1 */
  77
  78 #ifdef stderr
  79 #  undef stderr
  80 #endif
  81 #ifdef stdin
  82 #  undef stdin
  83 #endif
  84 #ifdef stdout
  85 #  undef stdout
  86 #endif
  87
  88 #endif
  89
  90 /* Don't use macros versions of this functions on VxWorks since they cause
  91    imcompatible changes in some VxWorks versions */
  92 #ifdef __vxworks
  93 #undef getchar
  94 #undef putchar
  95 #undef feof
  96 #undef ferror
  97 #undef fileno
  98 #endif
  99
 100 int
 101 __gnat_feof (FILE *stream)
 102 {
 103   return (feof (stream));
 104 }
 105
 106 int
 107 __gnat_ferror (FILE *stream)
 108 {
 109    return (ferror (stream));
 110 }
 111
 112 int
 113 __gnat_fileno (FILE *stream)
 114 {
 115    return (fileno (stream));
 116 }
 117
 118 /* on some systems, the constants for seek are not defined, if so, then
 119    provide the conventional definitions */
 120
 121 #ifndef SEEK_SET
 122 #define SEEK_SET 0  /* Set file pointer to offset                           */
 123 #define SEEK_CUR 1  /* Set file pointer to its current value plus offset    */
 124 #define SEEK_END 2  /* Set file pointer to the size of the file plus offset */
 125 #endif
 126
 127 /* if L_tmpnam is not set, use a large number that should be safe */
 128 #ifndef L_tmpnam
 129 #define L_tmpnam 256
 130 #endif
 131
 132 int    __gnat_constant_eof      = EOF;
 133 int    __gnat_constant_iofbf    = _IOFBF;
 134 int    __gnat_constant_iolbf    = _IOLBF;
 135 int    __gnat_constant_ionbf    = _IONBF;
 136 int    __gnat_constant_l_tmpnam = L_tmpnam;
 137 int    __gnat_constant_seek_cur = SEEK_CUR;
 138 int    __gnat_constant_seek_end = SEEK_END;
 139 int    __gnat_constant_seek_set = SEEK_SET;
 140
 141 FILE *
 142 __gnat_constant_stderr (void)
 143 {
 144   return stderr;
 145 }
 146
 147 FILE *
 148 __gnat_constant_stdin (void)
 149 {
 150   return stdin;
 151 }
 152
 153 FILE *
 154 __gnat_constant_stdout (void)
 155 {
 156   return stdout;
 157 }
 158
 159 char *
 160 __gnat_full_name (char *nam, char *buffer)
 161 {
 162 #ifdef RTSS
 163   /* RTSS applications have no current-directory notion, so RTSS file I/O
 164      requests must use fully qualified path names, such as:
 165        c:\temp\MyFile.txt (for a file system object)
 166        \\.\MyDevice0 (for a device object)
 167    */
 168   if (nam[1] == ':' || nam[0] == '\\')
 169     strcpy (buffer, nam);
 170   else
 171     buffer[0] = '\0';
 172
 173 #elif defined (__MINGW32__)
 174   /* If this is a device file return it as is;
 175      under Windows NT a device file ends with ":".  */
 176   if (nam[strlen (nam) - 1] == ':')
 177     strcpy (buffer, nam);
 178   else
 179     {
 180       char *p;
 181
 182       _fullpath (buffer, nam, __gnat_max_path_len);
 183
 184       for (p = buffer; *p; p++)
 185         if (*p == '/')
 186           *p = '\\';
 187     }
 188
 189 #elif defined (__FreeBSD__) || defined (__DragonFly__) || defined (__OpenBSD__)
 190
 191   /* Use realpath function which resolves links and references to . and ..
 192      on those Unix systems that support it. Note that GNU/Linux provides it but
 193      cannot handle more than 5 symbolic links in a full name, so we use the
 194      getcwd approach instead. */
 195   realpath (nam, buffer);
 196
 197 #elif defined (__vxworks)
 198
 199   /* On VxWorks systems, an absolute path can be represented (depending on
 200      the host platform) as either /dir/file, or device:/dir/file, or
 201      device:drive_letter:/dir/file. Use the __gnat_is_absolute_path
 202      to verify it. */
 203
 204   int length;
 205
 206   if (__gnat_is_absolute_path (nam, strlen (nam)))
 207     strcpy (buffer, nam);
 208
 209   else
 210     {
 211       length = __gnat_max_path_len;
 212       __gnat_get_current_dir (buffer, &length);
 213       strncat (buffer, nam, __gnat_max_path_len - length - 1);
 214     }
 215
 216 #else
 217   if (nam[0] != '/')
 218     {
 219       char *p = getcwd (buffer, __gnat_max_path_len);
 220
 221       if (p == 0)
 222         {
 223           buffer[0] = '\0';
 224           return 0;
 225         }
 226
 227
 228       /* If the name returned is an absolute path, it is safe to append '/'
 229          to the path and concatenate the name of the file. */
 230       if (buffer[0] == '/')
 231         strcat (buffer, "/");
 232
 233       strcat (buffer, nam);
 234     }
 235   else
 236     strcpy (buffer, nam);
 237 #endif
 238
 239   return buffer;
 240 }
 241
 242 #ifdef _WIN32
 243   /* On Windows we want to use the fseek/fteel supporting large files. This
 244      issue is due to the fact that a long on Win64 is still a 32 bits value */
 245 __int64
 246 __gnat_ftell64 (FILE *stream)
 247 {
 248   return _ftelli64 (stream);
 249 }
 250
 251 int
 252 __gnat_fseek64 (FILE *stream, __int64 offset, int origin)
 253 {
 254   return _fseeki64 (stream, offset, origin);
 255 }
 256
 257 #elif defined (__linux__) || defined (__sun__) || defined (__FreeBSD__) \
 258   || defined (__APPLE__)
 259 /* section for platforms having ftello/fseeko */
 260
 261 __int64
 262 __gnat_ftell64 (FILE *stream)
 263 {
 264   return (__int64)ftello (stream);
 265 }
 266
 267 int
 268 __gnat_fseek64 (FILE *stream, __int64 offset, int origin)
 269 {
 270   /* make sure that the offset is not bigger than the OS off_t, if so return
 271      with error as this mean that we are trying to handle files larger than
 272      2Gb on a patform not supporting it. */
 273   if ((off_t)offset == offset)
 274     return fseeko (stream, (off_t) offset, origin);
 275   else
 276     return -1;
 277 }
 278
 279 #else
 280
 281 __int64
 282 __gnat_ftell64 (FILE *stream)
 283 {
 284   return (__int64)ftell (stream);
 285 }
 286
 287 int
 288 __gnat_fseek64 (FILE *stream, __int64 offset, int origin)
 289 {
 290   /* make sure that the offset is not bigger than the OS off_t, if so return
 291      with error as this mean that we are trying to handle files larger than
 292      2Gb on a patform not supporting it. */
 293   if ((off_t)offset == offset)
 294     return fseek (stream, (off_t) offset, origin);
 295   else
 296     return -1;
 297 }
 298 #endif
 299
 300 /* Returns true if the path names a fifo (i.e. a named pipe). */
 301 int
 302 __gnat_is_fifo (const char* path)
 303 {
 304 /* Posix defines S_ISFIFO as a macro. If the macro doesn't exist, we return
 305    false. */
 306 #ifdef S_ISFIFO
 307   struct stat buf;
 308   const int status = stat(path, &buf);
 309   if (status == 0)
 310     return S_ISFIFO(buf.st_mode);
 311 #endif
 312
 313   /* S_ISFIFO is not available, or stat got an error (probably
 314      file not found). */
 315   return 0;
 316 }
 317
 318 #ifdef __cplusplus
 319 }
 320 #endif