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 * 3. 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 * $FreeBSD: src/lib/libc/gen/scandir.c,v 1.5.6.1 2001/03/05 09:52:13 obrien Exp $ 30 * 31 * @(#)scandir.c 8.3 (Berkeley) 1/2/94 32 */ 33 34 /* 35 * Scan the directory dirname calling select to make a list of selected 36 * directory entries then sort using qsort and compare routine dcomp. 37 * Returns the number of entries and a pointer to a list of pointers to 38 * struct dirent (through namelist). Returns -1 if there were any errors. 39 */ 40 41 #include "namespace.h" 42 #include <sys/types.h> 43 #include <sys/stat.h> 44 #include <dirent.h> 45 #include <limits.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include "un-namespace.h" 49 50 #include "gen_private.h" 51 52 int 53 scandir(const char *dirname, struct dirent ***namelist, 54 int (*select)(const struct dirent *), 55 int (*dcomp)(const struct dirent **, const struct dirent **)) 56 { 57 struct dirent *d, *p, **names = NULL; 58 size_t arraysz, nitems = 0; 59 struct stat stb; 60 DIR *dirp; 61 62 if ((dirp = opendir(dirname)) == NULL) 63 return(-1); 64 if (_fstat(dirp->dd_fd, &stb) < 0) 65 goto fail; 66 67 /* 68 * Estimate the array size by taking the size of the directory file 69 * and dividing it by a multiple of the minimum size entry. 70 * Ensure that the size does fit into memory without overflooding. 71 */ 72 if (stb.st_size / 24 > SIZE_T_MAX) 73 goto fail; 74 arraysz = stb.st_size / 24; 75 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 76 if (names == NULL) 77 goto fail; 78 79 while ((d = readdir(dirp)) != NULL) { 80 if (select != NULL && !(*select)(d)) 81 continue; /* just selected names */ 82 /* 83 * Make a minimum size copy of the data 84 */ 85 p = (struct dirent *)malloc(_DIRENT_DIRSIZ(d)); 86 if (p == NULL) 87 goto fail; 88 p->d_ino = d->d_ino; 89 p->d_type = d->d_type; 90 p->d_namlen = d->d_namlen; 91 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 92 /* 93 * Check to make sure the array has space left and 94 * realloc the maximum size. 95 */ 96 if (nitems >= arraysz) { 97 const int inc = 10; /* increase by this much */ 98 struct dirent **names2; 99 100 names2 = (struct dirent **)realloc((char *)names, 101 (arraysz + inc) * sizeof(struct dirent *)); 102 if (names2 == NULL) { 103 free(p); 104 goto fail; 105 } 106 names = names2; 107 arraysz += inc; 108 } 109 names[nitems++] = p; 110 } 111 closedir(dirp); 112 if (nitems && dcomp != NULL) 113 qsort(names, nitems, sizeof(struct dirent *), 114 (int (*)(const void *, const void *))dcomp); 115 *namelist = names; 116 return(nitems); 117 118 fail: 119 while (nitems > 0) 120 free(names[--nitems]); 121 free(names); 122 closedir(dirp); 123 return -1; 124 } 125 126 /* 127 * Alphabetic order comparison routine for those who want it. 128 */ 129 int 130 alphasort(const struct dirent **d1, const struct dirent **d2) 131 { 132 return(strcmp((*d1)->d_name, (*d2)->d_name)); 133 } 134