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- /*
- * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org>
- *
- * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
- */
- #include <features.h>
- #include <alloca.h>
- #include <assert.h>
- #include <errno.h>
- #include <dirent.h>
- #include <stddef.h>
- #include <stdint.h>
- #include <string.h>
- #include <unistd.h>
- #include <sys/param.h>
- #include <sys/types.h>
- #include <sys/syscall.h>
- #if defined __UCLIBC_HAS_LFS__ && defined __NR_getdents64
- libc_hidden_proto(memcpy)
- libc_hidden_proto(lseek64)
- # ifndef offsetof
- # define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
- # endif
- struct kernel_dirent64
- {
- uint64_t d_ino;
- int64_t d_off;
- unsigned short d_reclen;
- unsigned char d_type;
- char d_name[256];
- };
- # define __NR___syscall_getdents64 __NR_getdents64
- static inline _syscall3(int, __syscall_getdents64, int, fd, unsigned char *, dirp, size_t, count);
- ssize_t attribute_hidden __getdents64 (int fd, char *buf, size_t nbytes);
- ssize_t attribute_hidden __getdents64 (int fd, char *buf, size_t nbytes)
- {
- struct dirent64 *dp;
- off64_t last_offset = -1;
- ssize_t retval;
- size_t red_nbytes;
- struct kernel_dirent64 *skdp, *kdp;
- const size_t size_diff = (offsetof (struct dirent64, d_name)
- - offsetof (struct kernel_dirent64, d_name));
- red_nbytes = MIN (nbytes - ((nbytes /
- (offsetof (struct dirent64, d_name) + 14)) * size_diff),
- nbytes - size_diff);
- dp = (struct dirent64 *) buf;
- skdp = kdp = alloca (red_nbytes);
- retval = __syscall_getdents64(fd, (char *)kdp, red_nbytes);
- if (retval == -1)
- return -1;
- while ((char *) kdp < (char *) skdp + retval) {
- const size_t alignment = __alignof__ (struct dirent64);
- /* Since kdp->d_reclen is already aligned for the kernel structure
- this may compute a value that is bigger than necessary. */
- size_t new_reclen = ((kdp->d_reclen + size_diff + alignment - 1)
- & ~(alignment - 1));
- if ((char *) dp + new_reclen > buf + nbytes) {
- /* Our heuristic failed. We read too many entries. Reset
- the stream. */
- assert (last_offset != -1);
- lseek64(fd, last_offset, SEEK_SET);
- if ((char *) dp == buf) {
- /* The buffer the user passed in is too small to hold even
- one entry. */
- __set_errno (EINVAL);
- return -1;
- }
- break;
- }
- last_offset = kdp->d_off;
- dp->d_ino = kdp->d_ino;
- dp->d_off = kdp->d_off;
- dp->d_reclen = new_reclen;
- dp->d_type = kdp->d_type;
- memcpy (dp->d_name, kdp->d_name,
- kdp->d_reclen - offsetof (struct kernel_dirent64, d_name));
- dp = (struct dirent64 *) ((char *) dp + new_reclen);
- kdp = (struct kernel_dirent64 *) (((char *) kdp) + kdp->d_reclen);
- }
- return (char *) dp - buf;
- }
- /* since getdents doesnt give us d_type but getdents64 does, try and
- * use getdents64 as much as possible */
- attribute_hidden strong_alias(__getdents64,__getdents)
- #endif /* __UCLIBC_HAS_LFS__ */
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