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 36 #if defined(LIBC_SCCS) && !defined(lint) 37 static char sccsid[] = "@(#)scandir.c 8.3 (Berkeley) 1/2/94"; 38 #endif /* LIBC_SCCS and not lint */ 39 40 /* 41 * Scan the directory dirname calling select to make a list of selected 42 * directory entries then sort using qsort and compare routine dcomp. 43 * Returns the number of entries and a pointer to a list of pointers to 44 * struct dirent (through namelist). Returns -1 if there were any errors. 45 */ 46 47 #include <sys/types.h> 48 #include <sys/stat.h> 49 #include <dirent.h> 50 #include <stdlib.h> 51 #include <string.h> 52 53 /* 54 * The DIRSIZ macro is the minimum record length which will hold the directory 55 * entry. This requires the amount of space in struct dirent without the 56 * d_name field, plus enough space for the name and a terminating nul byte 57 * (dp->d_namlen + 1), rounded up to a 4 byte boundary. 58 */ 59 #undef DIRSIZ 60 #define DIRSIZ(dp) \ 61 ((sizeof(struct dirent) - sizeof(dp)->d_name) + \ 62 (((dp)->d_namlen + 1 + 3) &~ 3)) 63 64 int 65 scandir(dirname, namelist, select, dcomp) 66 const char *dirname; 67 struct dirent ***namelist; 68 int (*select) __P((struct dirent *)); 69 int (*dcomp) __P((const void *, const void *)); 70 { 71 register struct dirent *d, *p, **names = NULL; 72 register size_t nitems = 0; 73 struct stat stb; 74 long arraysz; 75 DIR *dirp; 76 77 if ((dirp = opendir(dirname)) == NULL) 78 return(-1); 79 if (fstat(dirp->dd_fd, &stb) < 0) 80 goto fail; 81 82 /* 83 * estimate the array size by taking the size of the directory file 84 * and dividing it by a multiple of the minimum size entry. 85 */ 86 arraysz = (stb.st_size / 24); 87 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 88 if (names == NULL) 89 goto fail; 90 91 while ((d = readdir(dirp)) != NULL) { 92 if (select != NULL && !(*select)(d)) 93 continue; /* just selected names */ 94 /* 95 * Make a minimum size copy of the data 96 */ 97 p = (struct dirent *)malloc(DIRSIZ(d)); 98 if (p == NULL) 99 goto fail; 100 p->d_fileno = d->d_fileno; 101 p->d_type = d->d_type; 102 p->d_reclen = d->d_reclen; 103 p->d_namlen = d->d_namlen; 104 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 105 /* 106 * Check to make sure the array has space left and 107 * realloc the maximum size. 108 */ 109 if (nitems >= arraysz) { 110 const int inc = 10; /* increase by this much */ 111 struct dirent **names2; 112 113 names2 = (struct dirent **)realloc((char *)names, 114 (arraysz + inc) * sizeof(struct dirent *)); 115 if (names2 == NULL) { 116 free(p); 117 goto fail; 118 } 119 names = names2; 120 arraysz += inc; 121 } 122 names[nitems++] = p; 123 } 124 closedir(dirp); 125 if (nitems && dcomp != NULL) 126 qsort(names, nitems, sizeof(struct dirent *), dcomp); 127 *namelist = names; 128 return(nitems); 129 130 fail: 131 while (nitems > 0) 132 free(names[--nitems]); 133 free(names); 134 closedir(dirp); 135 return -1; 136 } 137 138 /* 139 * Alphabetic order comparison routine for those who want it. 140 */ 141 int 142 alphasort(d1, d2) 143 const void *d1; 144 const void *d2; 145 { 146 return(strcmp((*(struct dirent **)d1)->d_name, 147 (*(struct dirent **)d2)->d_name)); 148 } 149