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  * This library is free software; you can redistribute it and/or
  21  * modify it under the terms of the GNU Lesser General Public
  22  * License as published by the Free Software Foundation; either
  23  * version 2.1 of the License, or (at your option) any later version.
  24  *
  25  * This library is distributed in the hope that it will be useful,
  26  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  28  * Lesser General Public License for more details.
  29  *
  30  * You should have received a copy of the GNU Lesser General Public
  31  * License along with this library; if not, write to the Free Software
  32  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  33  *
  34  * Questions or comments about this library should be sent to:
  35  *
  36  * Lee Ward
  37  * Sandia National Laboratories, New Mexico
  38  * P.O. Box 5800
  39  * Albuquerque, NM 87185-1110
  40  *
  41  * lee@sandia.gov
  42  */
  43
  44 #include <unistd.h>
  45 #include <stdlib.h>
  46 #ifdef __GLIBC__
  47 #include <alloca.h>
  48 #endif
  49 #include <string.h>
  50 #include <errno.h>
  51 #include <sys/types.h>
  52 #include <sys/stat.h>
  53 #include <dirent.h>
  54 #include <sys/queue.h>
  55
  56 #include "sysio.h"
  57 #include "inode.h"
  58 #include "file.h"
  59 #include "sysio-symbols.h"
  60
  61 #ifndef __GNUC__
  62 #define __restrict
  63 #endif
  64
  65 static ssize_t
  66 filldirents(struct file *fil,
  67             char *buf, size_t nbytes,
  68             _SYSIO_OFF_T *__restrict basep)
  69 {
  70         _SYSIO_OFF_T opos;
  71         ssize_t cc;
  72
  73         if (!S_ISDIR(fil->f_ino->i_stbuf.st_mode))
  74                 return -ENOTDIR;
  75
  76         opos = fil->f_pos;
  77         cc =
  78             (*fil->f_ino->i_ops.inop_filldirentries)(fil->f_ino,
  79                                                      &fil->f_pos,
  80                                                      buf, nbytes);
  81         if (cc < 0)
  82                 return cc;
  83         *basep = opos;
  84         return cc;
  85 }
  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
 105         cc = filldirents(fil, buf, nbytes, basep);
 106         SYSIO_INTERFACE_RETURN(cc < 0 ? -1 : cc, cc < 0 ? (int )cc : 0);
 107 }
 108
 109 #ifdef _LARGEFILE64_SOURCE
 110 #undef getdirentries64
 111 sysio_sym_strong_alias(PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64)),
 112                        SYSIO_INTERFACE_NAME(getdirentries64))
 113 #endif
 114
 115 #undef getdirentries
 116
 117 #ifndef DIRENT64_IS_NATURAL
 118
 119 #ifndef EOVERFLOW
 120 #define EOVERFLOW       ERANGE
 121 #endif
 122
 123 #ifdef _DIRENT_HAVE_D_NAMLEN
 124 #define _namlen(dp)     ((dp)->d_namlen)
 125 #else
 126 #define _namlen(dp)     (strlen((dp)->d_name))
 127 #endif
 128
 129 #ifndef _rndup
 130 #define _rndup(n, boundary) \
 131         ((((n) + (boundary) - 1 ) / (boundary)) * (boundary))
 132 #endif
 133
 134 #define _dbaselen       ((size_t )&((struct dirent *)0)->d_name[0])
 135
 136 #ifdef __GLIBC__
 137 #define _dreclen(namlen) \
 138         ((_dbaselen + (namlen) + __alignof__ (struct dirent)) & \
 139          ~(__alignof__ (struct dirent) - 1))
 140 #else /* !defined(__GLIBC__) */
 141 #define _dreclen(namlen) \
 142         _rndup(_dbaselen + (namlen) + 1, sizeof(int))
 143 #endif
 144
 145 #ifndef BSD
 146 ssize_t
 147 SYSIO_INTERFACE_NAME(getdirentries)(int fd,
 148                                     char *buf,
 149                                     size_t nbytes,
 150                                     off_t * __restrict basep)
 151 #else
 152 int
 153 SYSIO_INTERFACE_NAME(getdirentries)(int fd,
 154                                     char *buf,
 155                                     int nbytes,
 156                                     long * __restrict basep)
 157 #endif
 158 {
 159         struct file *fil;
 160         _SYSIO_OFF_T b;
 161         ssize_t cc, count;
 162         struct dirent64 *d64p, d64;
 163         struct dirent *dp;
 164         size_t  n, reclen;
 165         void    *p;
 166         char    *cp;
 167         SYSIO_INTERFACE_DISPLAY_BLOCK;
 168
 169         SYSIO_INTERFACE_ENTER;
 170
 171         fil = _sysio_fd_find(fd);
 172         if (!(fil && fil->f_ino)) {
 173                 SYSIO_INTERFACE_RETURN(-1, -EBADF);
 174         }
 175
 176         count = cc = filldirents(fil, buf, nbytes, &b);
 177         d64p = (void *)buf;
 178         dp = (void *)buf;
 179         reclen = 0;
 180         while (cc > 0) {
 181                 n = _namlen(d64p);
 182                 reclen = _dreclen(n);
 183                 d64.d_ino = d64p->d_ino;
 184                 d64.d_off = d64p->d_off;
 185                 d64.d_type = d64p->d_type;
 186                 d64.d_reclen = d64p->d_reclen;
 187                 /*
 188                  * Copy name first.
 189                  */
 190                 (void )memcpy(dp->d_name, d64p->d_name, n);
 191                 /*
 192                  * Then, the rest.
 193                  */
 194                 dp->d_ino = d64.d_ino;
 195                 dp->d_off = d64.d_off;
 196                 if (dp->d_ino != d64.d_ino ||
 197                     dp->d_off != d64.d_off) {
 198                         /*
 199                          * If conversion failure then we are done.
 200                          */
 201                         if (cc == count) {
 202                                 /*
 203                                  * Couldn't process any entries. We return
 204                                  * the error now.
 205                                  */
 206                                 cc = - EOVERFLOW;
 207                         }
 208                         break;
 209                 }
 210                 fil->f_pos = dp->d_off;
 211                 dp->d_type = d64.d_type;
 212                 dp->d_reclen = reclen;
 213                 /*
 214                  * Fill the remainder with zeros.
 215                  */
 216                 p = (char *)dp + dp->d_reclen;
 217 #ifdef HAVE_D_NAMLEN
 218                 dp->d_namlen = n;
 219 #endif
 220                 cp = dp->d_name + n;
 221                 do {
 222                         *cp++ = 0;
 223                 } while (cp < (char *)p);
 224                 /*
 225                  * Advance.
 226                  */
 227                 dp = p;
 228                 cc -= d64.d_reclen;
 229                 d64p = (struct dirent64 *)((char *)d64p + d64.d_reclen);
 230         }
 231
 232         if (cc < 0)
 233                 SYSIO_INTERFACE_RETURN(-1, cc);
 234         cc = (char *)dp - buf;
 235         *basep = b;
 236         SYSIO_INTERFACE_RETURN(cc, 0);
 237 }
 238 #else /* !defined(DIRENT64_IS_NATURAL) */
 239 sysio_sym_strong_alias(PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries64),
 240                        SYSIO_INTERFACE_NAME(getdirentries)))
 241 #endif
 242
 243 #ifdef REDSTORM
 244 #undef __getdirentries
 245 sysio_sym_weak_alias(SYSIO_INTERFACE_NAME(getdirentries),
 246                      PREPEND(__, SYSIO_INTERFACE_NAME(getdirentries)))
 247 #endif
 248 #if defined(BSD) || defined(REDSTORM)
 249 #undef _getdirentries
 250 sysio_sym_weak_alias(SYSIO_INTERFACE_NAME(getdirentries),
 251                      PREPEND(_, SYSIO_INTERFACE_NAME(getdirentries)))
 252 #endif