1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * 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 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)scandir.c 5.10 (Berkeley) 2/23/91"; 36 #endif /* LIBC_SCCS and not lint */ 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 <sys/types.h> 46 #include <sys/stat.h> 47 #include <dirent.h> 48 #include <stdlib.h> 49 #include <string.h> 50 51 /* 52 * The DIRSIZ macro gives the minimum record length which will hold 53 * the directory entry. This requires the amount of space in struct dirent 54 * without the d_name field, plus enough space for the name with a terminating 55 * null byte (dp->d_namlen+1), rounded up to a 4 byte boundary. 56 */ 57 #undef DIRSIZ 58 #define DIRSIZ(dp) \ 59 ((sizeof (struct dirent) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3)) 60 61 int 62 scandir(dirname, namelist, select, dcomp) 63 const char *dirname; 64 struct dirent ***namelist; 65 int (*select) __P((struct dirent *)); 66 int (*dcomp) __P((const void *, const void *)); 67 { 68 register struct dirent *d, *p, **names; 69 register size_t nitems; 70 struct stat stb; 71 long arraysz; 72 DIR *dirp; 73 74 if ((dirp = opendir(dirname)) == NULL) 75 return(-1); 76 if (fstat(dirp->dd_fd, &stb) < 0) 77 return(-1); 78 79 /* 80 * estimate the array size by taking the size of the directory file 81 * and dividing it by a multiple of the minimum size entry. 82 */ 83 arraysz = (stb.st_size / 24); 84 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 85 if (names == NULL) 86 return(-1); 87 88 nitems = 0; 89 while ((d = readdir(dirp)) != NULL) { 90 if (select != NULL && !(*select)(d)) 91 continue; /* just selected names */ 92 /* 93 * Make a minimum size copy of the data 94 */ 95 p = (struct dirent *)malloc(DIRSIZ(d)); 96 if (p == NULL) 97 return(-1); 98 p->d_ino = d->d_ino; 99 p->d_reclen = d->d_reclen; 100 p->d_namlen = d->d_namlen; 101 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 102 /* 103 * Check to make sure the array has space left and 104 * realloc the maximum size. 105 */ 106 if (++nitems >= arraysz) { 107 if (fstat(dirp->dd_fd, &stb) < 0) 108 return(-1); /* just might have grown */ 109 arraysz = stb.st_size / 12; 110 names = (struct dirent **)realloc((char *)names, 111 arraysz * sizeof(struct dirent *)); 112 if (names == NULL) 113 return(-1); 114 } 115 names[nitems-1] = p; 116 } 117 closedir(dirp); 118 if (nitems && dcomp != NULL) 119 qsort(names, nitems, sizeof(struct dirent *), dcomp); 120 *namelist = names; 121 return(nitems); 122 } 123 124 /* 125 * Alphabetic order comparison routine for those who want it. 126 */ 127 int 128 alphasort(d1, d2) 129 const void *d1; 130 const void *d2; 131 { 132 return(strcmp((*(struct dirent **)d1)->d_name, 133 (*(struct dirent **)d2)->d_name)); 134 } 135