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.
7 /* L4: Just shortcut getdents* for now... */
17 #include <sys/param.h>
18 #include <sys/types.h>
19 #include <sys/syscall.h>
20 #include <bits/kernel_types.h>
21 #include <bits/kernel-features.h>
23 #if !(defined __UCLIBC_HAS_LFS__ && defined __NR_getdents64 && __WORDSIZE == 64)
24 /* If the condition above is met, __getdents is defined as an alias
25 * for __getdents64 (see getdents64.c). Otherwise...
28 /* With newer versions of linux, the getdents syscall returns d_type
29 * information after the name field.
31 * See __ASSUME_GETDENTS32_D_TYPE in glibc's kernel-features.h for specific
32 * version / arch details.
36 # define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
43 unsigned short int d_reclen;
47 ssize_t __getdents (int fd, char *buf, size_t nbytes) attribute_hidden;
49 #define __NR___syscall_getdents __NR_getdents
51 static __always_inline _syscall3(int, __syscall_getdents, int, fd, unsigned char *, kdirp, size_t, count)
54 #if defined __ASSUME_GETDENTS32_D_TYPE
56 ssize_t __getdents (int fd, char *buf, size_t nbytes)
60 retval = __syscall_getdents(fd, (unsigned char *)buf, nbytes);
62 /* The kernel added the d_type value after the name. Change
66 struct kernel_dirent k;
68 } *kbuf = (void *) buf;
70 while ((char *) kbuf < buf + retval) {
71 char d_type = *((char *) kbuf + kbuf->k.d_reclen - 1);
72 memmove (kbuf->u.d_name, kbuf->k.d_name,
73 strlen (kbuf->k.d_name) + 1);
74 kbuf->u.d_type = d_type;
76 kbuf = (void *) ((char *) kbuf + kbuf->k.d_reclen);
83 #elif defined NOT_FOR_L4 && (! defined __UCLIBC_HAS_LFS__ || ! defined __NR_getdents64)
85 ssize_t __getdents (int fd, char *buf, size_t nbytes)
88 off_t last_offset = -1;
91 struct kernel_dirent *skdp, *kdp;
92 const size_t size_diff = (offsetof (struct dirent, d_name)
93 - offsetof (struct kernel_dirent, d_name));
95 red_nbytes = MIN (nbytes - ((nbytes /
96 (offsetof (struct dirent, d_name) + 14)) * size_diff),
99 dp = (struct dirent *) buf;
100 skdp = kdp = alloca (red_nbytes);
102 retval = __syscall_getdents(fd, (unsigned char *)kdp, red_nbytes);
106 while ((char *) kdp < (char *) skdp + retval) {
107 const size_t alignment = __alignof__ (struct dirent);
108 /* Since kdp->d_reclen is already aligned for the kernel structure
109 this may compute a value that is bigger than necessary. */
110 size_t new_reclen = ((kdp->d_reclen + size_diff + alignment - 1)
112 if ((char *) dp + new_reclen > buf + nbytes) {
113 /* Our heuristic failed. We read too many entries. Reset
115 assert (last_offset != -1);
116 lseek(fd, last_offset, SEEK_SET);
118 if ((char *) dp == buf) {
119 /* The buffer the user passed in is too small to hold even
121 __set_errno (EINVAL);
127 last_offset = kdp->d_off;
128 dp->d_ino = kdp->d_ino;
129 dp->d_off = kdp->d_off;
130 dp->d_reclen = new_reclen;
131 dp->d_type = DT_UNKNOWN;
132 memcpy (dp->d_name, kdp->d_name,
133 kdp->d_reclen - offsetof (struct kernel_dirent, d_name));
134 dp = (struct dirent *) ((char *) dp + new_reclen);
135 kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen);
137 return (char *) dp - buf;
140 #elif __WORDSIZE == 32 && defined __UCLIBC_HAS_LFS__
142 extern __typeof(__getdents) __getdents64 /* attribute_hidden*/;
143 ssize_t __getdents (int fd, char *buf, size_t nbytes)
146 struct dirent64 *dp64;
147 ssize_t ret = __getdents64 (fd, buf, nbytes);
152 dp64 = (struct dirent64 *) buf;
154 while ((void *) dp64 < (void *) buf) {
155 dp = (struct dirent *) dp64;
156 dp->d_ino = dp64->d_ino;
157 dp->d_off = dp64->d_off;
158 dp->d_reclen = dp64->d_reclen;
159 dp->d_type = dp64->d_type;
160 memmove (dp->d_name, dp64->d_name, dp->d_reclen - offsetof (struct dirent64, d_name));
161 memmove (dp64, dp, dp->d_reclen);
162 dp64 = ((void *) dp64) + dp->d_reclen;
170 #if defined NOT_FOR_L4 && (defined __UCLIBC_HAS_LFS__ && ! defined __NR_getdents64)
171 attribute_hidden strong_alias(__getdents,__getdents64)