cde/programs/dtksh/ksh93/src/lib/libast/dir/getdents.c

   1 /*
   2  * CDE - Common Desktop Environment
   3  *
   4  * Copyright (c) 1993-2012, The Open Group. All rights reserved.
   5  *
   6  * These libraries and programs are free software; you can
   7  * redistribute them and/or modify them under the terms of the GNU
   8  * Lesser General Public License as published by the Free Software
   9  * Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  * These libraries and programs are distributed in the hope that
  13  * they will be useful, but WITHOUT ANY WARRANTY; without even the
  14  * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  15  * PURPOSE. See the GNU Lesser General Public License for more
  16  * details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with these librararies and programs; if not, write
  20  * to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
  21  * Floor, Boston, MA 02110-1301 USA
  22  */
  23 /* $XConsortium: getdents.c /main/3 1995/11/01 17:22:56 rswiston $ */
  24 /***************************************************************
  25 *                                                              *
  26 *                      AT&T - PROPRIETARY                      *
  27 *                                                              *
  28 *         THIS IS PROPRIETARY SOURCE CODE LICENSED BY          *
  29 *                          AT&T CORP.                          *
  30 *                                                              *
  31 *                Copyright (c) 1995 AT&T Corp.                 *
  32 *                     All Rights Reserved                      *
  33 *                                                              *
  34 *           This software is licensed by AT&T Corp.            *
  35 *       under the terms and conditions of the license in       *
  36 *       http://www.research.att.com/orgs/ssr/book/reuse        *
  37 *                                                              *
  38 *               This software was created by the               *
  39 *           Software Engineering Research Department           *
  40 *                    AT&T Bell Laboratories                    *
  41 *                                                              *
  42 *               For further information contact                *
  43 *                     gsf@research.att.com                     *
  44 *                                                              *
  45 ***************************************************************/
  46
  47 /* : : generated by proto : : */
  48
  49 #if !defined(__PROTO__)
  50 #if defined(__STDC__) || defined(__cplusplus) || defined(_proto) || defined(c_plusplus)
  51 #if defined(__cplusplus)
  52 #define __MANGLE__      "C"
  53 #else
  54 #define __MANGLE__
  55 #endif
  56 #define __STDARG__
  57 #define __PROTO__(x)    x
  58 #define __OTORP__(x)
  59 #define __PARAM__(n,o)  n
  60 #if !defined(__STDC__) && !defined(__cplusplus)
  61 #if !defined(c_plusplus)
  62 #define const
  63 #endif
  64 #define signed
  65 #define void            int
  66 #define volatile
  67 #define __V_            char
  68 #else
  69 #define __V_            void
  70 #endif
  71 #else
  72 #define __PROTO__(x)    ()
  73 #define __OTORP__(x)    x
  74 #define __PARAM__(n,o)  o
  75 #define __MANGLE__
  76 #define __V_            char
  77 #define const
  78 #define signed
  79 #define void            int
  80 #define volatile
  81 #endif
  82 #if defined(__cplusplus) || defined(c_plusplus)
  83 #define __VARARG__      ...
  84 #else
  85 #define __VARARG__
  86 #endif
  87 #if defined(__STDARG__)
  88 #define __VA_START__(p,a)       va_start(p,a)
  89 #else
  90 #define __VA_START__(p,a)       va_start(p)
  91 #endif
  92 #endif
  93 #include "dirlib.h"
  94
  95 #if _dir_ok || _lib_getdents
  96
  97 NoN(getdents)
  98
  99 #else
 100
 101 /*
 102  * getdents
 103  *
 104  * read directory entries into directory block
 105  *
 106  * NOTE: directory entries must fit within DIRBLKSIZ boundaries
 107  */
 108
 109 #ifndef MAXNAMLEN
 110 #define MAXNAMLEN       255
 111 #endif
 112
 113 #if _lib_dirread
 114 extern __MANGLE__ int           dirread __PROTO__((int, char*, int));
 115 #endif
 116 #if _lib_getdirentries
 117 extern __MANGLE__ int           getdirentries __PROTO__((int, char*, int, long*));
 118 #endif
 119
 120 ssize_t
 121 getdents __PARAM__((int fd, __V_* buf, size_t siz), (fd, buf, siz)) __OTORP__(int fd; __V_* buf; size_t siz;){
 122         struct stat             st;
 123
 124         if (siz < DIRBLKSIZ)
 125         {
 126                 errno = EINVAL;
 127                 return(-1);
 128         }
 129         if (fstat(fd, &st)) return(-1);
 130         if (!S_ISDIR(st.st_mode))
 131         {
 132 #ifdef ENOTDIR
 133                 errno = ENOTDIR;
 134 #else
 135                 errno = EBADF;
 136 #endif
 137                 return(-1);
 138         }
 139 #if _lib_getdirentries
 140         {
 141                 long            off;
 142                 return(getdirentries(fd, buf, siz, &off));
 143         }
 144 #else
 145 #if _lib_dirread
 146         {
 147                 register char*          sp;     /* system */
 148                 register struct dirent* up;     /* user */
 149                 char*                   u;
 150                 int                     n;
 151                 int                     m;
 152                 int                     i;
 153
 154                 m = (siz * 6) / 10;
 155                 m = roundof(m, 8);
 156                 sp = (char*)buf + siz - m - 1;
 157                 if (!(n = dirread(fd, sp, m))) return(0);
 158                 if (n > 0)
 159                 {
 160                         up = (struct dirent*)buf;
 161                         sp[n] = 0;
 162                         while (sp < (char*)buf + siz - m + n)
 163                         {
 164                                 i = 0;
 165                                 while (*sp >= '0' && *sp <= '9')
 166                                         i = 10 * i + *sp++ - '0';
 167                                 while (*sp && *sp != '\t') sp++;
 168                                 if (*sp++)
 169                                 {
 170                                         up->d_fileno = i;
 171                                         u = up->d_name;
 172                                         while ((*u = *sp++) && u < up->d_name + MAXNAMLEN) u++;
 173                                         *u = 0;
 174                                         up->d_reclen = sizeof(struct dirent) - sizeof(up->d_name) + (up->d_namlen = u - up->d_name) + 1;
 175                                         up->d_reclen = roundof(up->d_reclen, 8);
 176                                         up = (struct dirent*)((char*)up + up->d_reclen);
 177                                 }
 178                         }
 179                         return((char*)up - (char*)buf);
 180                 }
 181         }
 182 #else
 183 #if _mem_d_reclen_direct
 184         return(read(fd, buf, siz));
 185 #else
 186         {
 187
 188 #define MAXREC  roundof(sizeof(*up)-sizeof(up->d_name)+sizeof(sp->d_name)+1,8)
 189
 190                 register struct direct* sp;     /* system */
 191                 register struct dirent* up;     /* user */
 192                 register char*          s;
 193                 register char*          u;
 194                 int                     n;
 195                 int                     m;
 196                 char                    tmp[sizeof(sp->d_name) + 1];
 197
 198                 /*
 199                  * we assume sizeof(struct dirent) > sizeof(struct direct)
 200                  */
 201
 202                 up = (struct dirent*)buf;
 203                 n = (siz / MAXREC) * sizeof(struct direct);
 204                 if ((!(m = n & ~511) || m < MAXREC) && (!(m = n & ~255) || m < MAXREC)) m = n;
 205                 do
 206                 {
 207                         if ((n = read(fd, (char*)buf + siz - m, m)) <= 0) break;
 208                         sp = (struct direct*)((char*)buf + siz - m);
 209                         while (sp < (struct direct*)((char*)buf + siz - m + n))
 210                         {
 211                                 if (sp->d_ino)
 212                                 {
 213                                         up->d_fileno = sp->d_ino;
 214                                         s = sp->d_name;
 215                                         u = tmp;
 216                                         while (s < sp->d_name + sizeof(sp->d_name) && *s)
 217                                                 *u++ = *s++;
 218                                         *u = 0;
 219                                         strcpy(up->d_name, tmp);
 220                                         up->d_reclen = sizeof(struct dirent) - sizeof(up->d_name) + (up->d_namlen = u - tmp) + 1;
 221                                         up->d_reclen = roundof(up->d_reclen, 8);
 222                                         up = (struct dirent*)((char*)up + up->d_reclen);
 223                                 }
 224                                 sp++;
 225                         }
 226                 } while (up == (struct dirent*)buf);
 227                 return((char*)up - (char*)buf);
 228         }
 229 #endif
 230 #endif
 231 #endif
 232 }
 233
 234 #endif