gen/FreeBSD/scandir_b.c

   1 /*
   2  * Copyright (c) 1983, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static char sccsid[] = "@(#)scandir.c   8.3 (Berkeley) 1/2/94";
  32 #endif /* LIBC_SCCS and not lint */
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD: src/lib/libc/gen/scandir.c,v 1.9 2008/03/16 19:08:53 das Exp $");
  35
  36 /*
  37  * Scan the directory dirname calling select to make a list of selected
  38  * directory entries then sort using qsort and compare routine dcomp.
  39  * Returns the number of entries and a pointer to a list of pointers to
  40  * struct dirent (through namelist). Returns -1 if there were any errors.
  41  */
  42
  43 #include "namespace.h"
  44 #include <dirent.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include "un-namespace.h"
  48
  49 /*
  50  * The _GENERIC_DIRSIZ macro is the minimum record length which will hold the directory
  51  * entry.  This requires the amount of space in struct dirent without the
  52  * d_name field, plus enough space for the name and a terminating nul byte
  53  * (dp->d_namlen + 1), rounded up to a 4 byte boundary.
  54  */
  55
  56 int
  57 scandir_b(dirname, namelist, select, _dcomp)
  58         const char *dirname;
  59         struct dirent ***namelist;
  60         int (^select)(const struct dirent *);
  61         int (^_dcomp)(const struct dirent **, const struct dirent **);
  62 {
  63         struct dirent *d, *p, **names = NULL;
  64         size_t nitems = 0;
  65         long arraysz;
  66         DIR *dirp;
  67         int (^dcomp)(const void *, const void *) = (void *)_dcomp; /* see <rdar://problem/10293482> */
  68
  69         if ((dirp = opendir(dirname)) == NULL)
  70                 return(-1);
  71
  72         arraysz = 32;   /* initial estimate of the array size */
  73         names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *));
  74         if (names == NULL)
  75                 goto fail;
  76
  77         while ((d = readdir(dirp)) != NULL) {
  78                 if (select != NULL && !select(d))
  79                         continue;       /* just selected names */
  80                 /*
  81                  * Make a minimum size copy of the data
  82                  */
  83                 p = (struct dirent *)malloc(_GENERIC_DIRSIZ(d));
  84                 if (p == NULL)
  85                         goto fail;
  86                 p->d_fileno = d->d_fileno;
  87                 p->d_type = d->d_type;
  88                 p->d_reclen = d->d_reclen;
  89                 p->d_namlen = d->d_namlen;
  90                 bcopy(d->d_name, p->d_name, p->d_namlen + 1);
  91                 /*
  92                  * Check to make sure the array has space left and
  93                  * realloc the maximum size.
  94                  */
  95                 if (nitems >= arraysz) {
  96                         struct dirent **names2;
  97
  98                         names2 = (struct dirent **)realloc((char *)names,
  99                                 (arraysz * 2) * sizeof(struct dirent *));
 100                         if (names2 == NULL) {
 101                                 free(p);
 102                                 goto fail;
 103                         }
 104                         names = names2;
 105                         arraysz *= 2;
 106                 }
 107                 names[nitems++] = p;
 108         }
 109         closedir(dirp);
 110         if (nitems && dcomp != NULL)
 111                 qsort_b(names, nitems, sizeof(struct dirent *), dcomp);
 112         *namelist = names;
 113         return(nitems);
 114
 115 fail:
 116         while (nitems > 0)
 117                 free(names[--nitems]);
 118         free(names);
 119         closedir(dirp);
 120         return -1;
 121 }