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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/lib/libc/gen/scandir.c,v 1.5.6.1 2001/03/05 09:52:13 obrien Exp $ 34 * 35 * @(#)scandir.c 8.3 (Berkeley) 1/2/94 36 */ 37 38 /* 39 * Scan the directory dirname calling select to make a list of selected 40 * directory entries then sort using qsort and compare routine dcomp. 41 * Returns the number of entries and a pointer to a list of pointers to 42 * struct dirent (through namelist). Returns -1 if there were any errors. 43 */ 44 45 #include "namespace.h" 46 #include <sys/types.h> 47 #include <sys/stat.h> 48 #include <dirent.h> 49 #include <limits.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include "un-namespace.h" 53 54 int 55 scandir(const char *dirname, struct dirent ***namelist, 56 int (*select)(const struct dirent *), 57 int (*dcomp)(const struct dirent **, const struct dirent **)) 58 { 59 struct dirent *d, *p, **names = NULL; 60 size_t arraysz, nitems = 0; 61 struct stat stb; 62 DIR *dirp; 63 64 if ((dirp = opendir(dirname)) == NULL) 65 return(-1); 66 if (_fstat(dirp->dd_fd, &stb) < 0) 67 goto fail; 68 69 /* 70 * Estimate the array size by taking the size of the directory file 71 * and dividing it by a multiple of the minimum size entry. 72 * Ensure that the size does fit into memory without overflooding. 73 */ 74 if (stb.st_size / 24 > SIZE_T_MAX) 75 goto fail; 76 arraysz = stb.st_size / 24; 77 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 78 if (names == NULL) 79 goto fail; 80 81 while ((d = readdir(dirp)) != NULL) { 82 if (select != NULL && !(*select)(d)) 83 continue; /* just selected names */ 84 /* 85 * Make a minimum size copy of the data 86 */ 87 p = (struct dirent *)malloc(_DIRENT_DIRSIZ(d)); 88 if (p == NULL) 89 goto fail; 90 p->d_ino = d->d_ino; 91 p->d_type = d->d_type; 92 p->d_namlen = d->d_namlen; 93 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 94 /* 95 * Check to make sure the array has space left and 96 * realloc the maximum size. 97 */ 98 if (nitems >= arraysz) { 99 const int inc = 10; /* increase by this much */ 100 struct dirent **names2; 101 102 names2 = (struct dirent **)realloc((char *)names, 103 (arraysz + inc) * sizeof(struct dirent *)); 104 if (names2 == NULL) { 105 free(p); 106 goto fail; 107 } 108 names = names2; 109 arraysz += inc; 110 } 111 names[nitems++] = p; 112 } 113 closedir(dirp); 114 if (nitems && dcomp != NULL) 115 qsort(names, nitems, sizeof(struct dirent *), 116 (int (*)(const void *, const void *))dcomp); 117 *namelist = names; 118 return(nitems); 119 120 fail: 121 while (nitems > 0) 122 free(names[--nitems]); 123 free(names); 124 closedir(dirp); 125 return -1; 126 } 127 128 /* 129 * Alphabetic order comparison routine for those who want it. 130 */ 131 int 132 alphasort(const struct dirent **d1, const struct dirent **d2) 133 { 134 return(strcmp((*d1)->d_name, (*d2)->d_name)); 135 } 136