posix/confstr.c

   1 /* Copyright (C) 1991-2012 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 #include <stddef.h>
  19 #include <errno.h>
  20 #include <unistd.h>
  21 #include <string.h>
  22 #include <confstr.h>
  23 #include "../version.h"
  24
  25 /* If BUF is not NULL and LEN > 0, fill in at most LEN - 1 bytes
  26    of BUF with the value corresponding to NAME and zero-terminate BUF.
  27    Return the number of bytes required to hold NAME's entire value.  */
  28 size_t
  29 confstr (name, buf, len)
  30      int name;
  31      char *buf;
  32      size_t len;
  33 {
  34   const char *string = "";
  35   size_t string_len = 1;
  36
  37   /* Note that this buffer must be large enough for the longest strings
  38      used below.  */
  39   char restenvs[4 * sizeof "POSIX_V7_LPBIG_OFFBIG"];
  40
  41   switch (name)
  42     {
  43     case _CS_PATH:
  44       {
  45         static const char cs_path[] = CS_PATH;
  46         string = cs_path;
  47         string_len = sizeof (cs_path);
  48       }
  49       break;
  50
  51     case _CS_V7_WIDTH_RESTRICTED_ENVS:
  52       /* We have to return a newline-separated list of named of
  53          programming environements in which the widths of blksize_t,
  54          cc_t, mode_t, nfds_t, pid_t, ptrdiff_t, size_t, speed_t,
  55          ssize_t, suseconds_t, tcflag_t, useconds_t, wchar_t, and
  56          wint_t types are no greater than the width of type long.
  57
  58          Currently this means all environment which the system allows.  */
  59       string_len = 0;
  60 #ifndef _POSIX_V7_ILP32_OFF32
  61       if (__sysconf (_SC_V7_ILP32_OFF32) > 0)
  62 #endif
  63 #if !defined _POSIX_V7_ILP32_OFF32 || _POSIX_V7_ILP32_OFF32 > 0
  64         {
  65           memcpy (restenvs + string_len, "POSIX_V7_ILP32_OFF32",
  66                   sizeof "POSIX_V7_ILP32_OFF32" - 1);
  67           string_len += sizeof "POSIX_V7_ILP32_OFF32" - 1;
  68         }
  69 #endif
  70 #ifndef _POSIX_V7_ILP32_OFFBIG
  71       if (__sysconf (_SC_V7_ILP32_OFFBIG) > 0)
  72 #endif
  73 #if !defined _POSIX_V7_ILP32_OFFBIG || _POSIX_V7_ILP32_OFFBIG > 0
  74         {
  75           if (string_len)
  76             restenvs[string_len++] = '\n';
  77           memcpy (restenvs + string_len, "POSIX_V7_ILP32_OFFBIG",
  78                   sizeof "POSIX_V7_ILP32_OFFBIG" - 1);
  79           string_len += sizeof "POSIX_V7_ILP32_OFFBIG" - 1;
  80         }
  81 #endif
  82 #ifndef _POSIX_V7_LP64_OFF64
  83       if (__sysconf (_SC_V7_LP64_OFF64) > 0)
  84 #endif
  85 #if !defined _POSIX_V7_LP64_OFF64 || _POSIX_V7_LP64_OFF64 > 0
  86         {
  87           if (string_len)
  88             restenvs[string_len++] = '\n';
  89           memcpy (restenvs + string_len, "POSIX_V7_LP64_OFF64",
  90                   sizeof "POSIX_V7_LP64_OFF64" - 1);
  91           string_len += sizeof "POSIX_V7_LP64_OFF64" - 1;
  92         }
  93 #endif
  94 #ifndef _POSIX_V7_LPBIG_OFFBIG
  95       if (__sysconf (_SC_V7_LPBIG_OFFBIG) > 0)
  96 #endif
  97 #if !defined _POSIX_V7_LPBIG_OFFBIG || _POSIX_V7_LPBIG_OFFBIG > 0
  98         {
  99           if (string_len)
 100             restenvs[string_len++] = '\n';
 101           memcpy (restenvs + string_len, "POSIX_V7_LPBIG_OFFBIG",
 102                   sizeof "POSIX_V7_LPBIG_OFFBIG" - 1);
 103           string_len += sizeof "POSIX_V7_LPBIG_OFFBIG" - 1;
 104         }
 105 #endif
 106       restenvs[string_len++] = '\0';
 107       string = restenvs;
 108       break;
 109
 110     case _CS_V6_WIDTH_RESTRICTED_ENVS:
 111       /* We have to return a newline-separated list of named of
 112          programming environements in which the widths of blksize_t,
 113          cc_t, mode_t, nfds_t, pid_t, ptrdiff_t, size_t, speed_t,
 114          ssize_t, suseconds_t, tcflag_t, useconds_t, wchar_t, and
 115          wint_t types are no greater than the width of type long.
 116
 117          Currently this means all environment which the system allows.  */
 118       string_len = 0;
 119 #ifndef _POSIX_V6_ILP32_OFF32
 120       if (__sysconf (_SC_V6_ILP32_OFF32) > 0)
 121 #endif
 122 #if !defined _POSIX_V6_ILP32_OFF32 || _POSIX_V6_ILP32_OFF32 > 0
 123         {
 124           memcpy (restenvs + string_len, "POSIX_V6_ILP32_OFF32",
 125                   sizeof "POSIX_V6_ILP32_OFF32" - 1);
 126           string_len += sizeof "POSIX_V6_ILP32_OFF32" - 1;
 127         }
 128 #endif
 129 #ifndef _POSIX_V6_ILP32_OFFBIG
 130       if (__sysconf (_SC_V6_ILP32_OFFBIG) > 0)
 131 #endif
 132 #if !defined _POSIX_V6_ILP32_OFFBIG || _POSIX_V6_ILP32_OFFBIG > 0
 133         {
 134           if (string_len)
 135             restenvs[string_len++] = '\n';
 136           memcpy (restenvs + string_len, "POSIX_V6_ILP32_OFFBIG",
 137                   sizeof "POSIX_V6_ILP32_OFFBIG" - 1);
 138           string_len += sizeof "POSIX_V6_ILP32_OFFBIG" - 1;
 139         }
 140 #endif
 141 #ifndef _POSIX_V6_LP64_OFF64
 142       if (__sysconf (_SC_V6_LP64_OFF64) > 0)
 143 #endif
 144 #if !defined _POSIX_V6_LP64_OFF64 || _POSIX_V6_LP64_OFF64 > 0
 145         {
 146           if (string_len)
 147             restenvs[string_len++] = '\n';
 148           memcpy (restenvs + string_len, "POSIX_V6_LP64_OFF64",
 149                   sizeof "POSIX_V6_LP64_OFF64" - 1);
 150           string_len += sizeof "POSIX_V6_LP64_OFF64" - 1;
 151         }
 152 #endif
 153 #ifndef _POSIX_V6_LPBIG_OFFBIG
 154       if (__sysconf (_SC_V6_LPBIG_OFFBIG) > 0)
 155 #endif
 156 #if !defined _POSIX_V6_LPBIG_OFFBIG || _POSIX_V6_LPBIG_OFFBIG > 0
 157         {
 158           if (string_len)
 159             restenvs[string_len++] = '\n';
 160           memcpy (restenvs + string_len, "POSIX_V6_LPBIG_OFFBIG",
 161                   sizeof "POSIX_V6_LPBIG_OFFBIG" - 1);
 162           string_len += sizeof "POSIX_V6_LPBIG_OFFBIG" - 1;
 163         }
 164 #endif
 165       restenvs[string_len++] = '\0';
 166       string = restenvs;
 167       break;
 168
 169     case _CS_V5_WIDTH_RESTRICTED_ENVS:
 170       /* We have to return a newline-separated list of named of
 171          programming environements in which the widths of blksize_t,
 172          cc_t, mode_t, nfds_t, pid_t, ptrdiff_t, size_t, speed_t,
 173          ssize_t, suseconds_t, tcflag_t, useconds_t, wchar_t, and
 174          wint_t types are no greater than the width of type long.
 175
 176          Currently this means all environment which the system allows.  */
 177       string_len = 0;
 178 #ifndef _XBS5_ILP32_OFF32
 179       if (__sysconf (_SC_XBS5_ILP32_OFF32) > 0)
 180 #endif
 181 #if !defined _XBS5_ILP32_OFF32 || _XBS5_ILP32_OFF32 > 0
 182         {
 183           memcpy (restenvs + string_len, "XBS5_ILP32_OFF32",
 184                   sizeof "XBS5_ILP32_OFF32" - 1);
 185           string_len += sizeof "XBS5_ILP32_OFF32" - 1;
 186         }
 187 #endif
 188 #ifndef _XBS5_ILP32_OFFBIG
 189       if (__sysconf (_SC_XBS5_ILP32_OFFBIG) > 0)
 190 #endif
 191 #if !defined _XBS5_ILP32_OFFBIG || _XBS5_ILP32_OFFBIG > 0
 192         {
 193           if (string_len)
 194             restenvs[string_len++] = '\n';
 195           memcpy (restenvs + string_len, "XBS5_ILP32_OFFBIG",
 196                   sizeof "XBS5_ILP32_OFFBIG" - 1);
 197           string_len += sizeof "XBS5_ILP32_OFFBIG" - 1;
 198         }
 199 #endif
 200 #ifndef _XBS5_LP64_OFF64
 201       if (__sysconf (_SC_XBS5_LP64_OFF64) > 0)
 202 #endif
 203 #if !defined _XBS5_LP64_OFF64 || _XBS5_LP64_OFF64 > 0
 204         {
 205           if (string_len)
 206             restenvs[string_len++] = '\n';
 207           memcpy (restenvs + string_len, "XBS5_LP64_OFF64",
 208                   sizeof "XBS5_LP64_OFF64" - 1);
 209           string_len += sizeof "XBS5_LP64_OFF64" - 1;
 210         }
 211 #endif
 212 #ifndef _XBS5_LPBIG_OFFBIG
 213       if (__sysconf (_SC_XBS5_LPBIG_OFFBIG) > 0)
 214 #endif
 215 #if !defined _XBS5_LPBIG_OFFBIG || _XBS5_LPBIG_OFFBIG > 0
 216         {
 217           if (string_len)
 218             restenvs[string_len++] = '\n';
 219           memcpy (restenvs + string_len, "XBS5_LPBIG_OFFBIG",
 220                   sizeof "XBS5_LPBIG_OFFBIG" - 1);
 221           string_len += sizeof "XBS5_LPBIG_OFFBIG" - 1;
 222         }
 223 #endif
 224       restenvs[string_len++] = '\0';
 225       string = restenvs;
 226       break;
 227
 228     case _CS_XBS5_ILP32_OFF32_CFLAGS:
 229     case _CS_POSIX_V6_ILP32_OFF32_CFLAGS:
 230     case _CS_POSIX_V7_ILP32_OFF32_CFLAGS:
 231 #ifdef __ILP32_OFF32_CFLAGS
 232 # if _POSIX_V7_ILP32_OFF32 == -1
 233 #  error "__ILP32_OFF32_CFLAGS should not be defined"
 234 # elif !defined _POSIX_V7_ILP32_OFF32
 235       if (__sysconf (_SC_V7_ILP32_OFF32) < 0)
 236         break;
 237 # endif
 238       string = __ILP32_OFF32_CFLAGS;
 239       string_len = sizeof (__ILP32_OFF32_CFLAGS);
 240 #endif
 241       break;
 242
 243     case _CS_XBS5_ILP32_OFFBIG_CFLAGS:
 244     case _CS_POSIX_V6_ILP32_OFFBIG_CFLAGS:
 245     case _CS_POSIX_V7_ILP32_OFFBIG_CFLAGS:
 246 #ifdef __ILP32_OFFBIG_CFLAGS
 247 # if _POSIX_V7_ILP32_OFFBIG == -1
 248 #  error "__ILP32_OFFBIG_CFLAGS should not be defined"
 249 # elif !defined _POSIX_V7_ILP32_OFFBIG
 250       if (__sysconf (_SC_V7_ILP32_OFFBIG) < 0)
 251         break;
 252 # endif
 253       string = __ILP32_OFFBIG_CFLAGS;
 254       string_len = sizeof (__ILP32_OFFBIG_CFLAGS);
 255 #endif
 256       break;
 257
 258     case _CS_XBS5_LP64_OFF64_CFLAGS:
 259     case _CS_POSIX_V6_LP64_OFF64_CFLAGS:
 260     case _CS_POSIX_V7_LP64_OFF64_CFLAGS:
 261 #ifdef __LP64_OFF64_CFLAGS
 262 # if _POSIX_V7_LP64_OFF64 == -1
 263 #  error "__LP64_OFF64_CFLAGS should not be defined"
 264 # elif !defined _POSIX_V7_LP64_OFF64
 265       if (__sysconf (_SC_V7_LP64_OFF64) < 0)
 266         break;
 267 # endif
 268       string = __LP64_OFF64_CFLAGS;
 269       string_len = sizeof (__LP64_OFF64_CFLAGS);
 270 #endif
 271       break;
 272
 273     case _CS_XBS5_ILP32_OFF32_LDFLAGS:
 274     case _CS_POSIX_V6_ILP32_OFF32_LDFLAGS:
 275     case _CS_POSIX_V7_ILP32_OFF32_LDFLAGS:
 276 #ifdef __ILP32_OFF32_LDFLAGS
 277 # if _POSIX_V7_ILP32_OFF32 == -1
 278 #  error "__ILP32_OFF32_LDFLAGS should not be defined"
 279 # elif !defined _POSIX_V7_ILP32_OFF32
 280       if (__sysconf (_SC_V7_ILP32_OFF32) < 0)
 281         break;
 282 # endif
 283       string = __ILP32_OFF32_LDFLAGS;
 284       string_len = sizeof (__ILP32_OFF32_LDFLAGS);
 285 #endif
 286       break;
 287
 288     case _CS_XBS5_ILP32_OFFBIG_LDFLAGS:
 289     case _CS_POSIX_V6_ILP32_OFFBIG_LDFLAGS:
 290     case _CS_POSIX_V7_ILP32_OFFBIG_LDFLAGS:
 291 #ifdef __ILP32_OFFBIG_LDFLAGS
 292 # if _POSIX_V7_ILP32_OFFBIG == -1
 293 #  error "__ILP32_OFFBIG_LDFLAGS should not be defined"
 294 # elif !defined _POSIX_V7_ILP32_OFFBIG
 295       if (__sysconf (_SC_V7_ILP32_OFFBIG) < 0)
 296         break;
 297 # endif
 298       string = __ILP32_OFFBIG_LDFLAGS;
 299       string_len = sizeof (__ILP32_OFFBIG_LDFLAGS);
 300 #endif
 301       break;
 302
 303     case _CS_XBS5_LP64_OFF64_LDFLAGS:
 304     case _CS_POSIX_V6_LP64_OFF64_LDFLAGS:
 305     case _CS_POSIX_V7_LP64_OFF64_LDFLAGS:
 306 #ifdef __LP64_OFF64_LDFLAGS
 307 # if _POSIX_V7_LP64_OFF64 == -1
 308 #  error "__LP64_OFF64_LDFLAGS should not be defined"
 309 # elif !defined _POSIX_V7_LP64_OFF64
 310       if (__sysconf (_SC_V7_LP64_OFF64) < 0)
 311         break;
 312 # endif
 313       string = __LP64_OFF64_LDFLAGS;
 314       string_len = sizeof (__LP64_OFF64_LDFLAGS);
 315 #endif
 316       break;
 317
 318     case _CS_LFS_CFLAGS:
 319     case _CS_LFS_LINTFLAGS:
 320 #if _POSIX_V6_ILP32_OFF32 == 1 && _POSIX_V6_ILP32_OFFBIG == 1
 321 # define __LFS_CFLAGS "-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64"
 322       /* Signal that we want the new ABI.  */
 323       string = __LFS_CFLAGS;
 324       string_len = sizeof (__LFS_CFLAGS);
 325 #endif
 326       break;
 327
 328     case _CS_LFS_LDFLAGS:
 329     case _CS_LFS_LIBS:
 330       /* No special libraries or linker flags needed.  */
 331       break;
 332
 333     case _CS_LFS64_CFLAGS:
 334     case _CS_LFS64_LINTFLAGS:
 335 #define __LFS64_CFLAGS "-D_LARGEFILE64_SOURCE"
 336       string = __LFS64_CFLAGS;
 337       string_len = sizeof (__LFS64_CFLAGS);
 338       break;
 339
 340     case _CS_LFS64_LDFLAGS:
 341     case _CS_LFS64_LIBS:
 342       /* No special libraries or linker flags needed.  */
 343       break;
 344
 345     case _CS_XBS5_ILP32_OFF32_LIBS:
 346     case _CS_XBS5_ILP32_OFF32_LINTFLAGS:
 347     case _CS_XBS5_ILP32_OFFBIG_LIBS:
 348     case _CS_XBS5_ILP32_OFFBIG_LINTFLAGS:
 349     case _CS_XBS5_LP64_OFF64_LIBS:
 350     case _CS_XBS5_LP64_OFF64_LINTFLAGS:
 351     case _CS_XBS5_LPBIG_OFFBIG_CFLAGS:
 352     case _CS_XBS5_LPBIG_OFFBIG_LDFLAGS:
 353     case _CS_XBS5_LPBIG_OFFBIG_LIBS:
 354     case _CS_XBS5_LPBIG_OFFBIG_LINTFLAGS:
 355
 356     case _CS_POSIX_V6_ILP32_OFF32_LIBS:
 357     case _CS_POSIX_V6_ILP32_OFF32_LINTFLAGS:
 358     case _CS_POSIX_V6_ILP32_OFFBIG_LIBS:
 359     case _CS_POSIX_V6_ILP32_OFFBIG_LINTFLAGS:
 360     case _CS_POSIX_V6_LP64_OFF64_LIBS:
 361     case _CS_POSIX_V6_LP64_OFF64_LINTFLAGS:
 362     case _CS_POSIX_V6_LPBIG_OFFBIG_CFLAGS:
 363     case _CS_POSIX_V6_LPBIG_OFFBIG_LDFLAGS:
 364     case _CS_POSIX_V6_LPBIG_OFFBIG_LIBS:
 365     case _CS_POSIX_V6_LPBIG_OFFBIG_LINTFLAGS:
 366
 367     case _CS_POSIX_V7_ILP32_OFF32_LIBS:
 368     case _CS_POSIX_V7_ILP32_OFF32_LINTFLAGS:
 369     case _CS_POSIX_V7_ILP32_OFFBIG_LIBS:
 370     case _CS_POSIX_V7_ILP32_OFFBIG_LINTFLAGS:
 371     case _CS_POSIX_V7_LP64_OFF64_LIBS:
 372     case _CS_POSIX_V7_LP64_OFF64_LINTFLAGS:
 373     case _CS_POSIX_V7_LPBIG_OFFBIG_CFLAGS:
 374     case _CS_POSIX_V7_LPBIG_OFFBIG_LDFLAGS:
 375     case _CS_POSIX_V7_LPBIG_OFFBIG_LIBS:
 376     case _CS_POSIX_V7_LPBIG_OFFBIG_LINTFLAGS:
 377       /* GNU libc does not require special actions to use LFS functions.  */
 378       break;
 379
 380     case _CS_GNU_LIBC_VERSION:
 381       string = "glibc " VERSION;
 382       string_len = sizeof ("glibc " VERSION);
 383       break;
 384
 385     case _CS_GNU_LIBPTHREAD_VERSION:
 386 #ifdef LIBPTHREAD_VERSION
 387       string = LIBPTHREAD_VERSION;
 388       string_len = sizeof LIBPTHREAD_VERSION;
 389       break;
 390 #else
 391       /* No thread library.  */
 392       __set_errno (EINVAL);
 393       return 0;
 394 #endif
 395
 396     case _CS_V6_ENV:
 397     case _CS_V7_ENV:
 398       /* Maybe something else is needed in future.  */
 399       string = "POSIXLY_CORRECT=1";
 400       string_len = sizeof ("POSIXLY_CORRECT=1");
 401       break;
 402
 403     default:
 404       __set_errno (EINVAL);
 405       return 0;
 406     }
 407
 408   if (len > 0 && buf != NULL)
 409     {
 410       if (string_len <= len)
 411         memcpy (buf, string, string_len);
 412       else
 413         {
 414           memcpy (buf, string, len - 1);
 415           buf[len - 1] = '\0';
 416         }
 417     }
 418   return string_len;
 419 }
 420 libc_hidden_def (confstr)