--- /dev/null
+/*
+ * Copyright (C) 2016 CTERA Networks. All Rights Reserved.
+ * Author: Amir Goldstein <amir73il@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * t_dir_type
+ *
+ * print directory entries, optionally filtered by d_type
+ *
+ * ./t_dir_type <path> [u|f|d|c|b|l|p|s|w]
+ */
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+
+struct linux_dirent64 {
+ uint64_t d_ino;
+ int64_t d_off;
+ unsigned short d_reclen;
+ unsigned char d_type;
+ char d_name[0];
+};
+
+#define DT_MASK 15
+#define DT_MAX 15
+unsigned char type_to_char[DT_MAX] = {
+ [DT_UNKNOWN] = 'u',
+ [DT_DIR] = 'd',
+ [DT_REG] = 'f',
+ [DT_LNK] = 'l',
+ [DT_CHR] = 'c',
+ [DT_BLK] = 'b',
+ [DT_FIFO] = 'p',
+ [DT_SOCK] = 's',
+ [DT_WHT] = 'w',
+};
+
+#define DT_CHAR(t) type_to_char[(t)&DT_MASK]
+
+#define BUF_SIZE 4096
+
+int
+main(int argc, char *argv[])
+{
+ int fd, nread;
+ char buf[BUF_SIZE];
+ struct linux_dirent64 *d;
+ int bpos;
+ int type = -1; /* -1 means all types */
+ int ret = 1;
+
+ fd = open(argv[1], O_RDONLY | O_DIRECTORY);
+ if (fd < 0) {
+ perror("open");
+ exit(EXIT_FAILURE);
+ }
+
+ if (argc > 2 && argv[2][0]) {
+ char t = argv[2][0];
+
+ for (type = DT_MAX-1; type >= 0; type--)
+ if (DT_CHAR(type) == t)
+ break;
+ /* no match ends up with type = -1 */
+ }
+
+ for ( ; ; ) {
+ nread = syscall(SYS_getdents64, fd, buf, BUF_SIZE);
+ if (nread == -1) {
+ perror("getdents");
+ exit(EXIT_FAILURE);
+ }
+
+ if (nread == 0)
+ break;
+
+ for (bpos = 0; bpos < nread;) {
+ d = (struct linux_dirent64 *) (buf + bpos);
+ if (type < 0 || type == (int)d->d_type) {
+ ret = 0;
+ printf("%s %c\n", d->d_name, DT_CHAR(d->d_type));
+ }
+ bpos += d->d_reclen;
+ }
+ }
+
+ return ret;
+}