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 #include "gen_private.h" 55 56 int 57 scandir(const char *dirname, struct dirent ***namelist, 58 int (*select)(const struct dirent *), 59 int (*dcomp)(const struct dirent **, const struct dirent **)) 60 { 61 struct dirent *d, *p, **names = NULL; 62 size_t arraysz, nitems = 0; 63 struct stat stb; 64 DIR *dirp; 65 66 if ((dirp = opendir(dirname)) == NULL) 67 return(-1); 68 if (_fstat(dirp->dd_fd, &stb) < 0) 69 goto fail; 70 71 /* 72 * Estimate the array size by taking the size of the directory file 73 * and dividing it by a multiple of the minimum size entry. 74 * Ensure that the size does fit into memory without overflooding. 75 */ 76 if (stb.st_size / 24 > SIZE_T_MAX) 77 goto fail; 78 arraysz = stb.st_size / 24; 79 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 80 if (names == NULL) 81 goto fail; 82 83 while ((d = readdir(dirp)) != NULL) { 84 if (select != NULL && !(*select)(d)) 85 continue; /* just selected names */ 86 /* 87 * Make a minimum size copy of the data 88 */ 89 p = (struct dirent *)malloc(_DIRENT_DIRSIZ(d)); 90 if (p == NULL) 91 goto fail; 92 p->d_ino = d->d_ino; 93 p->d_type = d->d_type; 94 p->d_namlen = d->d_namlen; 95 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 96 /* 97 * Check to make sure the array has space left and 98 * realloc the maximum size. 99 */ 100 if (nitems >= arraysz) { 101 const int inc = 10; /* increase by this much */ 102 struct dirent **names2; 103 104 names2 = (struct dirent **)realloc((char *)names, 105 (arraysz + inc) * sizeof(struct dirent *)); 106 if (names2 == NULL) { 107 free(p); 108 goto fail; 109 } 110 names = names2; 111 arraysz += inc; 112 } 113 names[nitems++] = p; 114 } 115 closedir(dirp); 116 if (nitems && dcomp != NULL) 117 qsort(names, nitems, sizeof(struct dirent *), 118 (int (*)(const void *, const void *))dcomp); 119 *namelist = names; 120 return(nitems); 121 122 fail: 123 while (nitems > 0) 124 free(names[--nitems]); 125 free(names); 126 closedir(dirp); 127 return -1; 128 } 129 130 /* 131 * Alphabetic order comparison routine for those who want it. 132 */ 133 int 134 alphasort(const struct dirent **d1, const struct dirent **d2) 135 { 136 return(strcmp((*d1)->d_name, (*d2)->d_name)); 137 } 138