1 /* Copyright (c) 1982 Regents of the University of California */ 2 3 static char sccsid[] = "@(#)readdir.c 4.4 05/07/82"; 4 5 #include <sys/param.h> 6 #include <dir.h> 7 8 /* 9 * get next entry in a directory. 10 */ 11 struct direct * 12 readdir(dirp) 13 register DIR *dirp; 14 { 15 register struct direct *dp; 16 17 for (;;) { 18 if (dirp->dd_loc == 0) { 19 dirp->dd_size = read(dirp->dd_fd, dirp->dd_buf, 20 DIRBLKSIZ); 21 if (dirp->dd_size <= 0) 22 return NULL; 23 } 24 if (dirp->dd_loc >= dirp->dd_size) { 25 dirp->dd_loc = 0; 26 continue; 27 } 28 dp = (struct direct *)(dirp->dd_buf + dirp->dd_loc); 29 if (dp->d_reclen <= 0 || 30 dp->d_reclen > DIRBLKSIZ + 1 - dirp->dd_loc) 31 return NULL; 32 dirp->dd_loc += dp->d_reclen; 33 if (dp->d_ino == 0) 34 continue; 35 return (dp); 36 } 37 } 38