1 /* $NetBSD: scandir.c,v 1.6 1995/02/25 08:51:42 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)scandir.c 8.3 (Berkeley) 1/2/94"; 39 #else 40 static char rcsid[] = "$NetBSD: scandir.c,v 1.6 1995/02/25 08:51:42 cgd Exp $"; 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 /* 45 * Scan the directory dirname calling select to make a list of selected 46 * directory entries then sort using qsort and compare routine dcomp. 47 * Returns the number of entries and a pointer to a list of pointers to 48 * struct dirent (through namelist). Returns -1 if there were any errors. 49 */ 50 51 #include <sys/types.h> 52 #include <sys/stat.h> 53 #include <dirent.h> 54 #include <stdlib.h> 55 #include <string.h> 56 57 /* 58 * The DIRSIZ macro is the minimum record length which will hold the directory 59 * entry. This requires the amount of space in struct dirent without the 60 * d_name field, plus enough space for the name and a terminating nul byte 61 * (dp->d_namlen + 1), rounded up to a 4 byte boundary. 62 */ 63 #undef DIRSIZ 64 #define DIRSIZ(dp) \ 65 ((sizeof(struct dirent) - sizeof(dp)->d_name) + \ 66 (((dp)->d_namlen + 1 + 3) &~ 3)) 67 68 int 69 scandir(dirname, namelist, select, dcomp) 70 const char *dirname; 71 struct dirent ***namelist; 72 int (*select) __P((struct dirent *)); 73 int (*dcomp) __P((const void *, const void *)); 74 { 75 register struct dirent *d, *p, **names; 76 register size_t nitems; 77 struct stat stb; 78 long arraysz; 79 DIR *dirp; 80 81 if ((dirp = opendir(dirname)) == NULL) 82 return(-1); 83 if (fstat(dirp->dd_fd, &stb) < 0) 84 return(-1); 85 86 /* 87 * estimate the array size by taking the size of the directory file 88 * and dividing it by a multiple of the minimum size entry. 89 */ 90 arraysz = (stb.st_size / 24); 91 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 92 if (names == NULL) 93 return(-1); 94 95 nitems = 0; 96 while ((d = readdir(dirp)) != NULL) { 97 if (select != NULL && !(*select)(d)) 98 continue; /* just selected names */ 99 /* 100 * Make a minimum size copy of the data 101 */ 102 p = (struct dirent *)malloc(DIRSIZ(d)); 103 if (p == NULL) 104 return(-1); 105 p->d_ino = d->d_ino; 106 p->d_reclen = d->d_reclen; 107 p->d_namlen = d->d_namlen; 108 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 109 /* 110 * Check to make sure the array has space left and 111 * realloc the maximum size. 112 */ 113 if (++nitems >= arraysz) { 114 if (fstat(dirp->dd_fd, &stb) < 0) 115 return(-1); /* just might have grown */ 116 arraysz = stb.st_size / 12; 117 names = (struct dirent **)realloc((char *)names, 118 arraysz * sizeof(struct dirent *)); 119 if (names == NULL) 120 return(-1); 121 } 122 names[nitems-1] = 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 } 130 131 /* 132 * Alphabetic order comparison routine for those who want it. 133 */ 134 int 135 alphasort(d1, d2) 136 const void *d1; 137 const void *d2; 138 { 139 return(strcmp((*(struct dirent **)d1)->d_name, 140 (*(struct dirent **)d2)->d_name)); 141 } 142