2 * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org>
4 * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
8 #include <sys/syscall.h>
10 #ifdef __NR_getdents64
19 #include <sys/param.h>
20 #include <bits/wordsize.h>
21 #include <bits/uClibc_alloc.h>
23 struct kernel_dirent64
27 unsigned short d_reclen;
32 # define __NR___syscall_getdents64 __NR_getdents64
33 static __inline__ _syscall3(int, __syscall_getdents64, int, fd, unsigned char *, dirp, size_t, count)
35 ssize_t __getdents64 (int fd, char *buf, size_t nbytes)
38 off64_t last_offset = -1;
41 struct kernel_dirent64 *skdp, *kdp;
42 const size_t size_diff = (offsetof (struct dirent64, d_name)
43 - offsetof (struct kernel_dirent64, d_name));
45 red_nbytes = MIN (nbytes - ((nbytes /
46 (offsetof (struct dirent64, d_name) + 14)) * size_diff),
49 dp = (struct dirent64 *) buf;
50 skdp = kdp = stack_heap_alloc(red_nbytes);
52 retval = __syscall_getdents64(fd, (unsigned char *)kdp, red_nbytes);
54 stack_heap_free(skdp);
58 while ((char *) kdp < (char *) skdp + retval) {
59 const size_t alignment = __alignof__ (struct dirent64);
60 /* Since kdp->d_reclen is already aligned for the kernel structure
61 this may compute a value that is bigger than necessary. */
62 size_t new_reclen = ((kdp->d_reclen + size_diff + alignment - 1)
64 if ((char *) dp + new_reclen > buf + nbytes) {
65 /* Our heuristic failed. We read too many entries. Reset
67 assert (last_offset != -1);
68 lseek64(fd, last_offset, SEEK_SET);
70 if ((char *) dp == buf) {
71 /* The buffer the user passed in is too small to hold even
73 stack_heap_free(skdp);
80 last_offset = kdp->d_off;
81 dp->d_ino = kdp->d_ino;
82 dp->d_off = kdp->d_off;
83 dp->d_reclen = new_reclen;
84 dp->d_type = kdp->d_type;
85 memcpy (dp->d_name, kdp->d_name,
86 kdp->d_reclen - offsetof (struct kernel_dirent64, d_name));
87 dp = (struct dirent64 *) ((char *) dp + new_reclen);
88 kdp = (struct kernel_dirent64 *) (((char *) kdp) + kdp->d_reclen);
90 stack_heap_free(skdp);
91 return (char *) dp - buf;
94 #if __WORDSIZE == 64 || (defined __UCLIBC_HAS_LFS__ && !defined __NR_getdents)
95 /* since getdents doesnt give us d_type but getdents64 does, try and
96 * use getdents64 as much as possible */
97 strong_alias(__getdents64,__getdents)