libsysio/src/getdirentries.c

   1 /*
   2  *    This Cplant(TM) source code is the property of Sandia National
   3  *    Laboratories.
   4  *
   5  *    This Cplant(TM) source code is copyrighted by Sandia National
   6  *    Laboratories.
   7  *
   8  *    The redistribution of this Cplant(TM) source code is subject to the
   9  *    terms of the GNU Lesser General Public License
  10  *    (see cit/LGPL or http://www.gnu.org/licenses/lgpl.html)
  11  *
  12  *    Cplant(TM) Copyright 1998-2004 Sandia Corporation.
  13  *    Under the terms of Contract DE-AC04-94AL85000, there is a non-exclusive
  14  *    license for use of this work by or on behalf of the US Government.
  15  *    Export of this program may require a license from the United States
  16  *    Government.
  17  */
  18
  19 /*
  20  * #############################################################################
  21  * #
  22  * #     This Cplant(TM) source code is the property of Sandia National
  23  * #     Laboratories.
  24  * #
  25  * #     This Cplant(TM) source code is copyrighted by Sandia National
  26  * #     Laboratories.
  27  * #
  28  * #     The redistribution of this Cplant(TM) source code is subject to the
  29  * #     terms of the GNU Lesser General Public License
  30  * #     (see cit/LGPL or http://www.gnu.org/licenses/lgpl.html)
  31  * #
  32  * #     Cplant(TM) Copyright 1998-2004 Sandia Corporation.
  33  * #     Under the terms of Contract DE-AC04-94AL85000, there is a non-exclusive
  34  * #     license for use of this work by or on behalf of the US Government.
  35  * #     Export of this program may require a license from the United States
  36  * #     Government.
  37  * #
  38  * #############################################################################
  39  */
  40
  41 /*
  42  * This library is free software; you can redistribute it and/or
  43  * modify it under the terms of the GNU Lesser General Public
  44  * License as published by the Free Software Foundation; either
  45  * version 2.1 of the License, or (at your option) any later version.
  46  *
  47  * This library is distributed in the hope that it will be useful,
  48  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  49  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  50  * Lesser General Public License for more details.
  51  *
  52  * You should have received a copy of the GNU Lesser General Public
  53  * License along with this library; if not, write to the Free Software
  54  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  55  *
  56  * Questions or comments about this library should be sent to:
  57  *
  58  * Lee Ward
  59  * Sandia National Laboratories, New Mexico
  60  * P.O. Box 5800
  61  * Albuquerque, NM 87185-1110
  62  *
  63  * lee@sandia.gov
  64  */
  65
  66 #include <unistd.h>
  67 #include <stdlib.h>
  68 #ifdef __GLIBC__
  69 #include <alloca.h>
  70 #endif
  71 #include <string.h>
  72 #include <errno.h>
  73 #include <sys/types.h>
  74 #include <sys/stat.h>
  75 #include <dirent.h>
  76 #include <sys/queue.h>
  77
  78 #include "sysio.h"
  79 #include "inode.h"
  80 #include "file.h"
  81 #include "sysio-symbols.h"
  82
  83 #ifndef __GNUC__
  84 #define __restrict
  85 #endif
  86
  87 static ssize_t
  88 PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64))(int fd,
  89                                                   char *buf,
  90                                                   size_t nbytes,
  91                                                   _SYSIO_OFF_T * __restrict
  92                                                    basep)
  93 {
  94         struct file *fil;
  95         ssize_t cc;
  96         SYSIO_INTERFACE_DISPLAY_BLOCK;
  97
  98         SYSIO_INTERFACE_ENTER;
  99
 100         fil = _sysio_fd_find(fd);
 101         if (!(fil && fil->f_ino))
 102                 SYSIO_INTERFACE_RETURN(-1, -EBADF);
 103
 104         if (!S_ISDIR(fil->f_ino->i_stbuf.st_mode))
 105                 SYSIO_INTERFACE_RETURN(-1, -ENOTDIR);
 106
 107         cc =
 108             (*fil->f_ino->i_ops.inop_getdirentries)(fil->f_ino,
 109                                                     buf,
 110                                                     nbytes,
 111                                                     basep);
 112         SYSIO_INTERFACE_RETURN(cc < 0 ? -1 : cc, cc < 0 ? (int )cc : 0);
 113 }
 114
 115 #if _LARGEFILE64_SOURCE
 116 #undef getdirentries64
 117 sysio_sym_strong_alias(PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64)),
 118                        SYSIO_INTERFACE_NAME(getdirentries64))
 119 #endif
 120
 121 #undef getdirentries
 122
 123 #ifndef DIRENT64_IS_NATURAL
 124
 125 #ifndef EOVERFLOW
 126 #define EOVERFLOW       ERANGE
 127 #endif
 128
 129 #ifdef _DIRENT_HAVE_D_NAMLEN
 130 #define _namlen(dp)     ((dp)->d_namlen)
 131 #else
 132 #define _namlen(dp)     (strlen((dp)->d_name))
 133 #endif
 134
 135 #ifndef _rndup
 136 #define _rndup(n, boundary) \
 137         ((((n) + (boundary) - 1 ) / (boundary)) * (boundary))
 138 #endif
 139
 140 #ifndef BSD
 141 ssize_t
 142 SYSIO_INTERFACE_NAME(getdirentries)(int fd,
 143                                     char *buf,
 144                                     size_t nbytes,
 145                                     off_t * __restrict basep)
 146 #else
 147 int
 148 SYSIO_INTERFACE_NAME(getdirentries)(int fd,
 149                                     char *buf,
 150                                     int nbytes,
 151                                     long * __restrict basep)
 152 #endif
 153 {
 154         size_t inbytes;
 155         void    *ibuf;
 156         _SYSIO_OFF_T ibase;
 157         ssize_t cc;
 158         struct dirent *dp, *nxtdp;
 159 #if defined(BSD)
 160         int     off;
 161 #endif
 162         struct intnl_dirent *od64p, *d64p;
 163         size_t  n;
 164         size_t  reclen;
 165         char    *cp;
 166         SYSIO_INTERFACE_DISPLAY_BLOCK;
 167
 168 #define _dbaselen       ((size_t )&((struct dirent *)0)->d_name[0])
 169
 170 #ifdef __GLIBC__
 171 #define _dreclen(namlen) \
 172         ((_dbaselen + (namlen) + __alignof__ (struct dirent)) & \
 173          ~(__alignof__ (struct dirent) - 1))
 174 #else /* !defined(__GLIBC__) */
 175 #define _dreclen(namlen) \
 176         _rndup(_dbaselen + (namlen) + 1, sizeof(int))
 177 #endif
 178
 179 #if defined(__GLIBC__)
 180 #define _fast_alloc(n)  alloca(n)
 181 #define _fast_free(p)
 182 #else /* !defined(__GLIBC__) */
 183 #define _fast_alloc(n)  malloc(n)
 184 #define _fast_free(p)   free(p)
 185 #endif
 186
 187         SYSIO_INTERFACE_ENTER;
 188 #if defined(BSD)
 189         if (nbytes < 0)
 190                 SYSIO_INTERFACE_RETURN(-1, -EINVAL);
 191 #endif
 192
 193         inbytes = nbytes;
 194         if (inbytes > 8 * 1024) {
 195                 /*
 196                  * Limit stack use.
 197                  */
 198                 inbytes = 8 * 1024;
 199         }
 200         ibuf = _fast_alloc(inbytes);
 201         if (!ibuf)
 202                 SYSIO_INTERFACE_RETURN(-1, -ENOMEM);
 203
 204         dp = (struct dirent *)buf;
 205
 206         ibase = *basep;
 207         cc =
 208             PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64))(fd,
 209                                             ibuf,
 210                                             inbytes,
 211                                             &ibase);
 212         if (cc < 0) {
 213                 cc = -errno;
 214                 goto out;
 215         }
 216         *basep = (off_t )ibase;
 217         if (sizeof(*basep) != sizeof(ibase) && *basep != ibase) {
 218                 cc = -EOVERFLOW;
 219                 goto out;
 220         }
 221
 222 #if defined(BSD)
 223         off = *basep;
 224 #endif
 225         od64p = NULL;
 226         d64p = ibuf;
 227         for (;;) {
 228                 if (!cc)
 229                         break;
 230 #ifdef HAVE_D_NAMLEN
 231                 n = d64p->d_namlen;
 232 #else
 233                 n = strlen(d64p->d_name);
 234 #endif
 235                 reclen = _dreclen(n);
 236                 if (reclen >= (unsigned )nbytes)
 237                         break;
 238                 dp->d_ino = (ino_t )d64p->d_ino;
 239 #if !(defined(BSD))
 240                 dp->d_off = (off_t )d64p->d_off;
 241 #endif
 242                 if ((sizeof(dp->d_ino) != sizeof(d64p->d_ino) &&
 243                      dp->d_ino != d64p->d_ino)
 244                                 ||
 245 #if !(defined(BSD))
 246                     (sizeof(dp->d_off) != sizeof(d64p->d_off) &&
 247                      dp->d_off != d64p->d_off)
 248 #else
 249                     (off + (int )reclen < off)
 250 #endif
 251                     ) {
 252                         cc = -EOVERFLOW;
 253                         break;
 254                 }
 255                 dp->d_type = d64p->d_type;
 256                 dp->d_reclen = reclen;
 257                 nxtdp = (struct dirent *)((char *)dp + dp->d_reclen);
 258                 (void )memcpy(dp->d_name, d64p->d_name, n);
 259                 for (cp = dp->d_name + n; cp < (char *)nxtdp; *cp++ = '\0')
 260                         ;
 261                 cc -= d64p->d_reclen;
 262                 od64p = d64p;
 263                 d64p = (struct dirent64 *)((char *)d64p + d64p->d_reclen);
 264                 nbytes -= reclen;
 265 #if defined(BSD)
 266                 off += reclen;
 267 #endif
 268                 dp = nxtdp;
 269         }
 270
 271 out:
 272         _fast_free(ibuf);
 273
 274         if (dp == (struct dirent *)buf && cc < 0)
 275                 SYSIO_INTERFACE_RETURN(-1, (int )cc);
 276         cc = (char *)dp - buf;
 277         if (cc)
 278                 *basep =
 279 #if !(defined(BSD))
 280                     od64p->d_off;
 281 #else
 282                     off;
 283 #endif
 284         SYSIO_INTERFACE_RETURN(cc, 0);
 285
 286 #ifdef __GLIBC__
 287 #undef _fast_alloc
 288 #undef _fast_free
 289 #endif
 290 #undef _dreclen
 291 #undef _dbaselen
 292 }
 293 #else /* !defined(DIRENT64_IS_NATURAL) */
 294 sysio_sym_strong_alias(PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64),
 295                        SYSIO_INTERFACE_NAME(getdirentries)))
 296 #endif
 297
 298 #ifdef REDSTORM
 299 #undef __getdirentries
 300 sysio_sym_weak_alias(SYSIO_INTERFACE_NAME(getdirentries),
 301                      PREPEND(__, SYSIO_INTERFACE_NAME(getdirentries)))
 302 #endif
 303 #if defined(BSD) || defined(REDSTORM)
 304 #undef _getdirentries
 305 sysio_sym_weak_alias(SYSIO_INTERFACE_NAME(getdirentries),
 306                      PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries)))
 307 #endif