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 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)scandir.c 8.3 (Berkeley) 1/2/94"; 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 is the minimum record length which will hold the directory 53 * entry. This requires the amount of space in struct dirent without the 54 * d_name field, plus enough space for the name and a terminating nul byte 55 * (dp->d_namlen + 1), rounded up to a 4 byte boundary. 56 */ 57 #undef DIRSIZ 58 #define DIRSIZ(dp) \ 59 ((sizeof(struct dirent) - sizeof(dp)->d_name) + \ 60 (((dp)->d_namlen + 1 + 3) &~ 3)) 61 62 int 63 scandir(dirname, namelist, select, dcomp) 64 const char *dirname; 65 struct dirent ***namelist; 66 int (*select) __P((struct dirent *)); 67 int (*dcomp) __P((const void *, const void *)); 68 { 69 register struct dirent *d, *p, **names = NULL; 70 register size_t nitems = 0; 71 struct stat stb; 72 long arraysz; 73 DIR *dirp; 74 75 if ((dirp = opendir(dirname)) == NULL) 76 return(-1); 77 if (fstat(dirp->dd_fd, &stb) < 0) 78 goto fail; 79 80 /* 81 * estimate the array size by taking the size of the directory file 82 * and dividing it by a multiple of the minimum size entry. 83 */ 84 arraysz = (stb.st_size / 24); 85 names = (struct dirent **)malloc(arraysz * sizeof(struct dirent *)); 86 if (names == NULL) 87 goto fail; 88 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 goto fail; 98 p->d_fileno = d->d_fileno; 99 p->d_type = d->d_type; 100 p->d_reclen = d->d_reclen; 101 p->d_namlen = d->d_namlen; 102 bcopy(d->d_name, p->d_name, p->d_namlen + 1); 103 /* 104 * Check to make sure the array has space left and 105 * realloc the maximum size. 106 */ 107 if (nitems >= arraysz) { 108 const int inc = 10; /* increase by this much */ 109 struct dirent **names2; 110 111 names2 = (struct dirent **)realloc((char *)names, 112 (arraysz + inc) * sizeof(struct dirent *)); 113 if (names2 == NULL) { 114 free(p); 115 goto fail; 116 } 117 names = names2; 118 arraysz += inc; 119 } 120 names[nitems++] = p; 121 } 122 closedir(dirp); 123 if (nitems && dcomp != NULL) 124 qsort(names, nitems, sizeof(struct dirent *), dcomp); 125 *namelist = names; 126 return(nitems); 127 128 fail: 129 while (nitems > 0) 130 free(names[--nitems]); 131 free(names); 132 closedir(dirp); 133 return -1; 134 } 135 136 /* 137 * Alphabetic order comparison routine for those who want it. 138 */ 139 int 140 alphasort(d1, d2) 141 const void *d1; 142 const void *d2; 143 { 144 return(strcmp((*(struct dirent **)d1)->d_name, 145 (*(struct dirent **)d2)->d_name)); 146 } 147