From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org
Subject: Re: [PATCH 4/7] Consolidate Linux getdents{64} implementation
Date: Tue, 17 Apr 2018 19:42:00 -0000 [thread overview]
Message-ID: <be844c0d-d2c3-f19a-6fc9-ca155b604c15@linaro.org> (raw)
In-Reply-To: <58439e02-ad1d-2cdc-8d7c-fbc73fc8e2fc@linaro.org>
I will commit this shortly if no one opposes it.
> Unfortunately MIPS n64 only wire up getdents64 on Linux 3.10, so we
> still need to use the non-LFS one and adjust the buffer for the
> ABI. Below it is an updated patch for mips which first tried
> getdents64 and if it fails fallbacks to old syscall. I did a sniff
> test on a qemu-system mips64 with dirent tests and saw no regressions.
>
> ---
>
> * sysdeps/unix/sysv/linux/alpha/getdents.c: Add comments with alpha
> requirements.
> (_DIRENT_MATCHES_DIRENT64): Undef
> * sysdeps/unix/sysv/linux/alpha/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/arm/getdents64.c: Remove file.
> * sysdeps/unix/sysv/linux/generic/getdents.c: Likewise.
> * sysdeps/unix/sysv/linux/generic/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/generic/wordsize-32/getdents.c: Likewise.
> * sysdeps/unix/sysv/linux/getdents.c: Simplify implementation by
> use getdents64 syscalls as base.
> * sysdeps/unix/sysv/linux/getdents64.c: Likewise and add compatibility
> symbol if required.
> * sysdeps/unix/sysv/linux/hppa/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/i386/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/m68k/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/powerpc/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/s390/s390-32/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/sparc/sparc32/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/wordsize-64/getdents.c: Likewise.
> * sysdeps/unix/sysv/linux/wordsize-64/getdents64.c: Likewise.
> * sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c
> (__get_clockfreq_via_proc_openprom): Use __getdents64.
> * sysdeps/unix/sysv/linux/mips/mips64/getdents64.c: New file.
>
> ---
>
> diff --git a/sysdeps/unix/sysv/linux/alpha/getdents.c b/sysdeps/unix/sysv/linux/alpha/getdents.c
> index dfecfef..64ccf86 100644
> --- a/sysdeps/unix/sysv/linux/alpha/getdents.c
> +++ b/sysdeps/unix/sysv/linux/alpha/getdents.c
> @@ -1,3 +1,11 @@
> +/* Although Alpha defines _DIRENT_MATCHES_DIRENT64, 'struct dirent' and
> + 'struct dirent64' have slight different internal layout with d_ino
> + being a __ino_t on non-LFS version with an extra __pad field which should
> + be zeroed. */
> +
> +#include <dirent.h>
> +#undef _DIRENT_MATCHES_DIRENT64
> +#define _DIRENT_MATCHES_DIRENT64 0
> #define DIRENT_SET_DP_INO(dp, value) \
> do { (dp)->d_ino = (value); (dp)->__pad = 0; } while (0)
> #include <sysdeps/unix/sysv/linux/getdents.c>
> diff --git a/sysdeps/unix/sysv/linux/alpha/getdents64.c b/sysdeps/unix/sysv/linux/alpha/getdents64.c
> index 50f1368..53cf93c 100644
> --- a/sysdeps/unix/sysv/linux/alpha/getdents64.c
> +++ b/sysdeps/unix/sysv/linux/alpha/getdents64.c
> @@ -1 +1,10 @@
> +/* Although Alpha defines _DIRENT_MATCHES_DIRENT64, 'struct dirent' and
> + 'struct dirent64' have slight different internal layout with d_ino
> + being a __ino_t on non-LFS version with an extra __pad field which should
> + be zeroed. */
> +
> +#include <dirent.h>
> +/* It suppress the __getdents64 to __getdents alias. */
> +#undef _DIRENT_MATCHES_DIRENT64
> +#define _DIRENT_MATCHES_DIRENT64 0
> #include <sysdeps/unix/sysv/linux/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/arm/getdents64.c b/sysdeps/unix/sysv/linux/arm/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/arm/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/generic/getdents.c b/sysdeps/unix/sysv/linux/generic/getdents.c
> deleted file mode 100644
> index 14dbbc7..0000000
> --- a/sysdeps/unix/sysv/linux/generic/getdents.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -/* Defined in getdents64.c */
> diff --git a/sysdeps/unix/sysv/linux/generic/getdents64.c b/sysdeps/unix/sysv/linux/generic/getdents64.c
> deleted file mode 100644
> index 0f876b8..0000000
> --- a/sysdeps/unix/sysv/linux/generic/getdents64.c
> +++ /dev/null
> @@ -1,37 +0,0 @@
> -/* Copyright (C) 2011-2018 Free Software Foundation, Inc.
> - This file is part of the GNU C Library.
> - Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
> -
> - The GNU C Library is free software; you can redistribute it and/or
> - modify it under the terms of the GNU Lesser General Public
> - License as published by the Free Software Foundation; either
> - version 2.1 of the License, or (at your option) any later version.
> -
> - The GNU C Library is distributed in the hope that it will be useful,
> - but WITHOUT ANY WARRANTY; without even the implied warranty of
> - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> - Lesser General Public License for more details.
> -
> - You should have received a copy of the GNU Lesser General Public
> - License along with the GNU C Library. If not, see
> - <http://www.gnu.org/licenses/>. */
> -
> -#include <stddef.h>
> -#include <stdint.h>
> -#include <unistd.h>
> -#include <sys/types.h>
> -#include <bits/wordsize.h>
> -
> -#include <sysdep.h>
> -#include <sys/syscall.h>
> -
> -/* The kernel struct linux_dirent64 matches the 'struct getdents64' type. */
> -ssize_t
> -__getdents64 (int fd, char *buf, size_t nbytes)
> -{
> - return INLINE_SYSCALL (getdents64, 3, fd, buf, nbytes);
> -}
> -
> -#if __WORDSIZE == 64
> -strong_alias (__getdents64, __getdents)
> -#endif
> diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/getdents.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/getdents.c
> deleted file mode 100644
> index 7158fd1..0000000
> --- a/sysdeps/unix/sysv/linux/generic/wordsize-32/getdents.c
> +++ /dev/null
> @@ -1,115 +0,0 @@
> -/* Copyright (C) 1993-2018 Free Software Foundation, Inc.
> - This file is part of the GNU C Library.
> - Simplified from sysdeps/unix/sysv/linux/getdents.c.
> -
> - The GNU C Library is free software; you can redistribute it and/or
> - modify it under the terms of the GNU Lesser General Public
> - License as published by the Free Software Foundation; either
> - version 2.1 of the License, or (at your option) any later version.
> -
> - The GNU C Library is distributed in the hope that it will be useful,
> - but WITHOUT ANY WARRANTY; without even the implied warranty of
> - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> - Lesser General Public License for more details.
> -
> - You should have received a copy of the GNU Lesser General Public
> - License along with the GNU C Library. If not, see
> - <http://www.gnu.org/licenses/>. */
> -
> -#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 <sysdep.h>
> -#include <sys/syscall.h>
> -
> -/* Pack the dirent64 struct down into 32-bit offset/inode fields, and
> - ensure that no overflow occurs. */
> -ssize_t
> -__getdents (int fd, char *buf, size_t nbytes)
> -{
> - union
> - {
> - struct dirent64 k; /* Kernel structure. */
> - struct dirent u;
> - char b[1];
> - } *kbuf = (void *) buf, *outp, *inp;
> - size_t kbytes = nbytes;
> - off64_t last_offset = -1;
> - ssize_t retval;
> -
> - const size_t size_diff = (offsetof (struct dirent64, d_name)
> - - offsetof (struct dirent, d_name));
> - if (nbytes <= sizeof (struct dirent))
> - {
> - kbytes = nbytes + offsetof (struct dirent64, d_name)
> - - offsetof (struct dirent, d_name);
> - kbuf = __alloca(kbytes);
> - }
> -
> - retval = INLINE_SYSCALL (getdents64, 3, fd, kbuf, kbytes);
> - if (retval == -1)
> - return -1;
> -
> - /* These two pointers might alias the same memory buffer.
> - Standard C requires that we always use the same type for them,
> - so we must use the union type. */
> - inp = kbuf;
> - outp = (void *) buf;
> -
> - while (&inp->b < &kbuf->b + retval)
> - {
> - const size_t alignment = __alignof__ (struct dirent);
> - /* Since inp->k.d_reclen is already aligned for the kernel
> - structure this may compute a value that is bigger
> - than necessary. */
> - size_t old_reclen = inp->k.d_reclen;
> - size_t new_reclen = ((old_reclen - size_diff + alignment - 1)
> - & ~(alignment - 1));
> -
> - /* Copy the data out of the old structure into temporary space.
> - Then copy the name, which may overlap if BUF == KBUF. */
> - const uint64_t d_ino = inp->k.d_ino;
> - const int64_t d_off = inp->k.d_off;
> - const uint8_t d_type = inp->k.d_type;
> -
> - memmove (outp->u.d_name, inp->k.d_name,
> - old_reclen - offsetof (struct dirent64, d_name));
> -
> - /* Now we have copied the data from INP and access only OUTP. */
> -
> - outp->u.d_ino = d_ino;
> - outp->u.d_off = d_off;
> - if ((sizeof (outp->u.d_ino) != sizeof (inp->k.d_ino)
> - && outp->u.d_ino != d_ino)
> - || (sizeof (outp->u.d_off) != sizeof (inp->k.d_off)
> - && outp->u.d_off != d_off))
> - {
> - /* Overflow. If there was at least one entry before this one,
> - return them without error, otherwise signal overflow. */
> - if (last_offset != -1)
> - {
> - __lseek64 (fd, last_offset, SEEK_SET);
> - return outp->b - buf;
> - }
> - __set_errno (EOVERFLOW);
> - return -1;
> - }
> -
> - last_offset = d_off;
> - outp->u.d_reclen = new_reclen;
> - outp->u.d_type = d_type;
> -
> - inp = (void *) inp + old_reclen;
> - outp = (void *) outp + new_reclen;
> - }
> -
> - return outp->b - buf;
> -}
> diff --git a/sysdeps/unix/sysv/linux/getdents.c b/sysdeps/unix/sysv/linux/getdents.c
> index 591ce67..4e52729 100644
> --- a/sysdeps/unix/sysv/linux/getdents.c
> +++ b/sysdeps/unix/sysv/linux/getdents.c
> @@ -1,4 +1,5 @@
> -/* Copyright (C) 1993-2018 Free Software Foundation, Inc.
> +/* Get directory entries. Linux no-LFS version.
> + Copyright (C) 1993-2018 Free Software Foundation, Inc.
> This file is part of the GNU C Library.
>
> The GNU C Library is free software; you can redistribute it and/or
> @@ -12,260 +13,102 @@
> Lesser General Public License for more details.
>
> You should have received a copy of the GNU Lesser General Public
> - License along with the GNU C Library; if not, see
> + License along with the GNU C Library. If not, see
> <http://www.gnu.org/licenses/>. */
>
> -#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 <sysdep.h>
> -#include <sys/syscall.h>
> +#if !_DIRENT_MATCHES_DIRENT64
>
> -#include <linux/posix_types.h>
> +# include <unistd.h>
> +# include <string.h>
> +# include <errno.h>
>
> -#include <kernel-features.h>
> +# ifndef DIRENT_SET_DP_INO
> +# define DIRENT_SET_DP_INO(dp, value) (dp)->d_ino = (value)
> +# endif
>
> -/* For Linux we need a special version of this file since the
> - definition of `struct dirent' is not the same for the kernel and
> - the libc. There is one additional field which might be introduced
> - in the kernel structure in the future.
> -
> - Here is the kernel definition of `struct dirent' as of 2.1.20: */
> -
> -struct kernel_dirent
> - {
> - long int d_ino;
> - __kernel_off_t d_off;
> - unsigned short int d_reclen;
> - char d_name[256];
> - };
> -
> -struct kernel_dirent64
> - {
> - uint64_t d_ino;
> - int64_t d_off;
> - unsigned short int d_reclen;
> - unsigned char d_type;
> - char d_name[256];
> - };
> -
> -#ifndef __GETDENTS
> -# define __GETDENTS __getdents
> -#endif
> -#ifndef DIRENT_TYPE
> -# define DIRENT_TYPE struct dirent
> -#endif
> -#ifndef DIRENT_SET_DP_INO
> -# define DIRENT_SET_DP_INO(dp, value) (dp)->d_ino = (value)
> -#endif
> -
> -/* The problem here is that we cannot simply read the next NBYTES
> - bytes. We need to take the additional field into account. We use
> - some heuristic. Assuming the directory contains names with 14
> - characters on average we can compute an estimated number of entries
> - which fit in the buffer. Taking this number allows us to specify a
> - reasonable number of bytes to read. If we should be wrong, we can
> - reset the file descriptor. In practice the kernel is limiting the
> - amount of data returned much more then the reduced buffer size. */
> +/* Pack the dirent64 struct down into 32-bit offset/inode fields, and
> + ensure that no overflow occurs. */
> ssize_t
> -__GETDENTS (int fd, char *buf, size_t nbytes)
> +__getdents (int fd, char *buf, size_t nbytes)
> {
> + union
> + {
> + struct dirent64 k; /* Kernel structure. */
> + struct dirent u;
> + char b[1];
> + } *kbuf = (void *) buf, *outp, *inp;
> + size_t kbytes = nbytes;
> + off64_t last_offset = -1;
> ssize_t retval;
>
> - /* The d_ino and d_off fields in kernel_dirent and dirent must have
> - the same sizes and alignments. */
> - if (sizeof (DIRENT_TYPE) == sizeof (struct dirent)
> - && (sizeof (((struct kernel_dirent *) 0)->d_ino)
> - == sizeof (((struct dirent *) 0)->d_ino))
> - && (sizeof (((struct kernel_dirent *) 0)->d_off)
> - == sizeof (((struct dirent *) 0)->d_off))
> - && (offsetof (struct kernel_dirent, d_off)
> - == offsetof (struct dirent, d_off))
> - && (offsetof (struct kernel_dirent, d_reclen)
> - == offsetof (struct dirent, d_reclen)))
> - {
> - retval = INLINE_SYSCALL (getdents, 3, fd, buf, nbytes);
> +# define size_diff (offsetof (struct dirent64, d_name) \
> + - offsetof (struct dirent, d_name))
> + char kbuftmp[sizeof (struct dirent) + size_diff];
> + if (nbytes <= sizeof (struct dirent))
> + kbuf = (void*) kbuftmp;
>
> - /* The kernel added the d_type value after the name. Change
> - this now. */
> - if (retval != -1)
> - {
> - union
> - {
> - struct kernel_dirent k;
> - struct dirent u;
> - } *kbuf = (void *) buf;
> + retval = INLINE_SYSCALL_CALL (getdents64, fd, kbuf, kbytes);
> + if (retval == -1)
> + return -1;
>
> - while ((char *) kbuf < buf + retval)
> - {
> - char d_type = *((char *) kbuf + kbuf->k.d_reclen - 1);
> - memmove (kbuf->u.d_name, kbuf->k.d_name,
> - strlen (kbuf->k.d_name) + 1);
> - kbuf->u.d_type = d_type;
> + /* These two pointers might alias the same memory buffer.
> + Standard C requires that we always use the same type for them,
> + so we must use the union type. */
> + inp = kbuf;
> + outp = (void *) buf;
>
> - kbuf = (void *) ((char *) kbuf + kbuf->k.d_reclen);
> - }
> - }
> -
> - return retval;
> - }
> -
> - off64_t last_offset = -1;
> -
> -#ifdef __NR_getdents64
> - {
> - union
> + while (&inp->b < &kbuf->b + retval)
> {
> - struct kernel_dirent64 k;
> - DIRENT_TYPE u;
> - char b[1];
> - } *kbuf = (void *) buf, *outp, *inp;
> - size_t kbytes = nbytes;
> - if (offsetof (DIRENT_TYPE, d_name)
> - < offsetof (struct kernel_dirent64, d_name)
> - && nbytes <= sizeof (DIRENT_TYPE))
> - {
> - kbytes = (nbytes + offsetof (struct kernel_dirent64, d_name)
> - - offsetof (DIRENT_TYPE, d_name));
> - kbuf = __alloca(kbytes);
> - }
> - retval = INLINE_SYSCALL (getdents64, 3, fd, kbuf, kbytes);
> - const size_t size_diff = (offsetof (struct kernel_dirent64, d_name)
> - - offsetof (DIRENT_TYPE, d_name));
> -
> - /* Return the error if encountered. */
> - if (retval == -1)
> - return -1;
> -
> - /* If the structure returned by the kernel is identical to what we
> - need, don't do any conversions. */
> - if (offsetof (DIRENT_TYPE, d_name)
> - == offsetof (struct kernel_dirent64, d_name)
> - && sizeof (outp->u.d_ino) == sizeof (inp->k.d_ino)
> - && sizeof (outp->u.d_off) == sizeof (inp->k.d_off))
> - return retval;
> -
> - /* These two pointers might alias the same memory buffer.
> - Standard C requires that we always use the same type for them,
> - so we must use the union type. */
> - inp = kbuf;
> - outp = (void *) buf;
> -
> - while (&inp->b < &kbuf->b + retval)
> - {
> - const size_t alignment = __alignof__ (DIRENT_TYPE);
> - /* Since inp->k.d_reclen is already aligned for the kernel
> - structure this may compute a value that is bigger
> - than necessary. */
> - size_t old_reclen = inp->k.d_reclen;
> - size_t new_reclen = ((old_reclen - size_diff + alignment - 1)
> - & ~(alignment - 1));
> -
> - /* Copy the data out of the old structure into temporary space.
> - Then copy the name, which may overlap if BUF == KBUF. */
> - const uint64_t d_ino = inp->k.d_ino;
> - const int64_t d_off = inp->k.d_off;
> - const uint8_t d_type = inp->k.d_type;
> -
> - memmove (outp->u.d_name, inp->k.d_name,
> - old_reclen - offsetof (struct kernel_dirent64, d_name));
> -
> - /* Now we have copied the data from INP and access only OUTP. */
> -
> - DIRENT_SET_DP_INO (&outp->u, d_ino);
> - outp->u.d_off = d_off;
> - if ((sizeof (outp->u.d_ino) != sizeof (inp->k.d_ino)
> - && outp->u.d_ino != d_ino)
> - || (sizeof (outp->u.d_off) != sizeof (inp->k.d_off)
> - && outp->u.d_off != d_off))
> - {
> - /* Overflow. If there was at least one entry
> - before this one, return them without error,
> - otherwise signal overflow. */
> - if (last_offset != -1)
> - {
> - __lseek64 (fd, last_offset, SEEK_SET);
> - return outp->b - buf;
> - }
> - __set_errno (EOVERFLOW);
> - return -1;
> - }
> -
> - last_offset = d_off;
> - outp->u.d_reclen = new_reclen;
> - outp->u.d_type = d_type;
> -
> - inp = (void *) inp + old_reclen;
> - outp = (void *) outp + new_reclen;
> - }
> -
> - return outp->b - buf;
> - }
> -#endif
> - {
> - size_t red_nbytes;
> - struct kernel_dirent *skdp, *kdp;
> - const size_t size_diff = (offsetof (DIRENT_TYPE, d_name)
> - - offsetof (struct kernel_dirent, d_name));
> -
> - red_nbytes = MIN (nbytes
> - - ((nbytes / (offsetof (DIRENT_TYPE, d_name) + 14))
> - * size_diff),
> - nbytes - size_diff);
> -
> - skdp = kdp = __alloca (red_nbytes);
> -
> - retval = INLINE_SYSCALL (getdents, 3, fd, (char *) kdp, red_nbytes);
> -
> - if (retval == -1)
> - return -1;
> -
> - DIRENT_TYPE *dp = (DIRENT_TYPE *) buf;
> - while ((char *) kdp < (char *) skdp + retval)
> - {
> - const size_t alignment = __alignof__ (DIRENT_TYPE);
> - /* 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;
> - }
> + const size_t alignment = __alignof__ (struct dirent);
> + /* Since inp->k.d_reclen is already aligned for the kernel
> + structure this may compute a value that is bigger
> + than necessary. */
> + size_t old_reclen = inp->k.d_reclen;
> + size_t new_reclen = ((old_reclen - size_diff + alignment - 1)
> + & ~(alignment - 1));
> +
> + /* Copy the data out of the old structure into temporary space.
> + Then copy the name, which may overlap if BUF == KBUF. */
> + const uint64_t d_ino = inp->k.d_ino;
> + const int64_t d_off = inp->k.d_off;
> + const uint8_t d_type = inp->k.d_type;
> +
> + memmove (outp->u.d_name, inp->k.d_name,
> + old_reclen - offsetof (struct dirent64, d_name));
> +
> + /* Now we have copied the data from INP and access only OUTP. */
> +
> + DIRENT_SET_DP_INO (&outp->u, d_ino);
> + outp->u.d_off = d_off;
> + if ((sizeof (outp->u.d_ino) != sizeof (inp->k.d_ino)
> + && outp->u.d_ino != d_ino)
> + || (sizeof (outp->u.d_off) != sizeof (inp->k.d_off)
> + && outp->u.d_off != d_off))
> + {
> + /* Overflow. If there was at least one entry before this one,
> + return them without error, otherwise signal overflow. */
> + if (last_offset != -1)
> + {
> + __lseek64 (fd, last_offset, SEEK_SET);
> + return outp->b - buf;
> + }
> + __set_errno (EOVERFLOW);
> + return -1;
> + }
> +
> + last_offset = d_off;
> + outp->u.d_reclen = new_reclen;
> + outp->u.d_type = d_type;
> +
> + inp = (void *) inp + old_reclen;
> + outp = (void *) outp + new_reclen;
> + }
>
> - last_offset = kdp->d_off;
> - DIRENT_SET_DP_INO(dp, kdp->d_ino);
> - dp->d_off = kdp->d_off;
> - dp->d_reclen = new_reclen;
> - dp->d_type = *((char *) kdp + kdp->d_reclen - 1);
> - memcpy (dp->d_name, kdp->d_name,
> - kdp->d_reclen - offsetof (struct kernel_dirent, d_name));
> + return outp->b - buf;
> +}
>
> - dp = (DIRENT_TYPE *) ((char *) dp + new_reclen);
> - kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen);
> - }
> +# undef DIRENT_SET_DP_INO
>
> - return (char *) dp - buf;
> - }
> -}
> +#endif /* _DIRENT_MATCHES_DIRENT64 */
> diff --git a/sysdeps/unix/sysv/linux/getdents64.c b/sysdeps/unix/sysv/linux/getdents64.c
> index 805917e..f37fe15 100644
> --- a/sysdeps/unix/sysv/linux/getdents64.c
> +++ b/sysdeps/unix/sysv/linux/getdents64.c
> @@ -1,3 +1,77 @@
> -#define __GETDENTS __getdents64
> -#define DIRENT_TYPE struct dirent64
> -#include <sysdeps/unix/sysv/linux/getdents.c>
> +/* Get directory entries. Linux LFS version.
> + Copyright (C) 1997-2018 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library. If not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <string.h>
> +#include <dirent.h>
> +#include <errno.h>
> +
> +/* The kernel struct linux_dirent64 matches the 'struct getdents64' type. */
> +ssize_t
> +__getdents64 (int fd, char *buf, size_t nbytes)
> +{
> + return INLINE_SYSCALL_CALL (getdents64, fd, buf, nbytes);
> +}
> +
> +#if _DIRENT_MATCHES_DIRENT64
> +strong_alias (__getdents64, __getdents)
> +#else
> +# include <shlib-compat.h>
> +
> +# if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)
> +
> +# include <olddirent.h>
> +
> +/* kernel definition of as of 3.2. */
> +struct compat_linux_dirent
> +{
> + /* Both d_ino and d_off are compat_ulong_t which are defined in all
> + architectures as 'u32'. */
> + uint32_t d_ino;
> + uint32_t d_off;
> + unsigned short d_reclen;
> + char d_name[1];
> +};
> +
> +ssize_t
> +__old_getdents64 (int fd, char *buf, size_t nbytes)
> +{
> + ssize_t retval = INLINE_SYSCALL_CALL (getdents, fd, buf, nbytes);
> +
> + /* The kernel added the d_type value after the name. Change this now. */
> + if (retval != -1)
> + {
> + union
> + {
> + struct compat_linux_dirent k;
> + struct dirent u;
> + } *kbuf = (void *) buf;
> +
> + while ((char *) kbuf < buf + retval)
> + {
> + char d_type = *((char *) kbuf + kbuf->k.d_reclen - 1);
> + memmove (kbuf->u.d_name, kbuf->k.d_name,
> + strlen (kbuf->k.d_name) + 1);
> + kbuf->u.d_type = d_type;
> +
> + kbuf = (void *) ((char *) kbuf + kbuf->k.d_reclen);
> + }
> + }
> + return retval;
> +}
> +# endif /* SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2) */
> +#endif /* _DIRENT_MATCHES_DIRENT64 */
> diff --git a/sysdeps/unix/sysv/linux/hppa/getdents64.c b/sysdeps/unix/sysv/linux/hppa/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/hppa/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/i386/getdents64.c b/sysdeps/unix/sysv/linux/i386/getdents64.c
> deleted file mode 100644
> index 0a2c194..0000000
> --- a/sysdeps/unix/sysv/linux/i386/getdents64.c
> +++ /dev/null
> @@ -1,39 +0,0 @@
> -/* Copyright (C) 2000-2018 Free Software Foundation, Inc.
> - This file is part of the GNU C Library.
> -
> - The GNU C Library is free software; you can redistribute it and/or
> - modify it under the terms of the GNU Lesser General Public
> - License as published by the Free Software Foundation; either
> - version 2.1 of the License, or (at your option) any later version.
> -
> - The GNU C Library is distributed in the hope that it will be useful,
> - but WITHOUT ANY WARRANTY; without even the implied warranty of
> - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> - Lesser General Public License for more details.
> -
> - You should have received a copy of the GNU Lesser General Public
> - License along with the GNU C Library; if not, see
> - <http://www.gnu.org/licenses/>. */
> -
> -#define __GETDENTS __getdents64
> -#define DIRENT_TYPE struct dirent64
> -
> -#include <sysdeps/unix/sysv/linux/getdents.c>
> -
> -#include <shlib-compat.h>
> -
> -#undef __READDIR
> -#undef __GETDENTS
> -#undef DIRENT_TYPE
> -
> -#if SHLIB_COMPAT(libc, GLIBC_2_1, GLIBC_2_2)
> -
> -#include <olddirent.h>
> -
> -#define __GETDENTS __old_getdents64
> -#define DIRENT_TYPE struct __old_dirent64
> -#define kernel_dirent old_kernel_dirent
> -#define kernel_dirent64 old_kernel_dirent64
> -
> -#include <sysdeps/unix/sysv/linux/getdents.c>
> -#endif
> diff --git a/sysdeps/unix/sysv/linux/m68k/getdents64.c b/sysdeps/unix/sysv/linux/m68k/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/m68k/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/mips/mips64/getdents64.c b/sysdeps/unix/sysv/linux/mips/mips64/getdents64.c
> new file mode 100644
> index 0000000..5b62791
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/mips/mips64/getdents64.c
> @@ -0,0 +1,113 @@
> +/* Get directory entries. Linux/MIPSn64 LFS version.
> + Copyright (C) 2018 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library. If not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <string.h>
> +#include <dirent.h>
> +#include <errno.h>
> +#include <assert.h>
> +#include <sys/param.h>
> +#include <unistd.h>
> +#include <scratch_buffer.h>
> +
> +ssize_t
> +__getdents64 (int fd, char *buf, size_t nbytes)
> +{
> + ssize_t ret;
> +#ifdef __NR_getdents64
> + ret = INLINE_SYSCALL_CALL (getdents64, fd, buf, nbytes);
> + if (ret != -1)
> + return ret;
> +#endif
> +
> + /* Unfortunately getdents64 was only wire-up for MIPS n64 on Linux 3.10.
> + If syscall is not available it need to fallback to old one. */
> +
> + struct kernel_dirent
> + {
> + unsigned long d_ino;
> + unsigned long d_off;
> + unsigned short int d_reclen;
> + char d_name[256];
> + };
> +
> + const size_t size_diff = (offsetof (struct dirent64, d_name)
> + - offsetof (struct kernel_dirent, d_name));
> +
> + size_t red_nbytes = MIN (nbytes
> + - ((nbytes / (offsetof (struct dirent64, d_name)
> + + 14)) * size_diff),
> + nbytes - size_diff);
> +
> + struct scratch_buffer tmpbuf;
> + scratch_buffer_init (&tmpbuf);
> + if (!scratch_buffer_set_array_size (&tmpbuf, red_nbytes, sizeof (uint8_t)))
> + INLINE_SYSCALL_ERROR_RETURN_VALUE (ENOMEM);
> +
> + struct kernel_dirent *skdp, *kdp;
> + skdp = kdp = tmpbuf.data;
> +
> + ssize_t retval = INLINE_SYSCALL_CALL (getdents, fd, kdp, red_nbytes);
> + if (retval == -1)
> + {
> + scratch_buffer_free (&tmpbuf);
> + return -1;
> + }
> +
> + off64_t last_offset = -1;
> + struct dirent64 *dp = (struct dirent64 *) buf;
> + 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)
> + {
> + scratch_buffer_free (&tmpbuf);
> + INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
> + }
> +
> + 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 = *((char *) kdp + kdp->d_reclen - 1);
> + memcpy (dp->d_name, kdp->d_name,
> + kdp->d_reclen - offsetof (struct kernel_dirent, d_name));
> +
> + dp = (struct dirent64 *) ((char *) dp + new_reclen);
> + kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen);
> + }
> +
> + scratch_buffer_free (&tmpbuf);
> + return (char *) dp - buf;
> +}
> +#if _DIRENT_MATCHES_DIRENT64
> +strong_alias (__getdents64, __getdents)
> +#endif
> diff --git a/sysdeps/unix/sysv/linux/powerpc/getdents64.c b/sysdeps/unix/sysv/linux/powerpc/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/powerpc/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/getdents64.c b/sysdeps/unix/sysv/linux/s390/s390-32/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/s390/s390-32/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/getdents64.c b/sysdeps/unix/sysv/linux/sparc/sparc32/getdents64.c
> deleted file mode 100644
> index 0c75fb5..0000000
> --- a/sysdeps/unix/sysv/linux/sparc/sparc32/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -#include <sysdeps/unix/sysv/linux/i386/getdents64.c>
> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c b/sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c
> index c54d301..6838a77 100644
> --- a/sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c
> +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c
> @@ -90,12 +90,12 @@ __get_clockfreq_via_proc_openprom (void)
> if (obp_fd != -1)
> {
> unsigned long int buf[4096 / sizeof (unsigned long int)];
> - struct dirent *dirp = (struct dirent *) buf;
> + struct dirent64 *dirp = (struct dirent64 *) buf;
> ssize_t len;
>
> - while ((len = __getdents (obp_fd, (char *) dirp, sizeof (buf))) > 0)
> + while ((len = __getdents64 (obp_fd, (char *) dirp, sizeof (buf))) > 0)
> {
> - struct dirent *this_dirp = dirp;
> + struct dirent64 *this_dirp = dirp;
>
> while (len > 0)
> {
> @@ -140,7 +140,7 @@ __get_clockfreq_via_proc_openprom (void)
> break;
>
> len -= this_dirp->d_reclen;
> - this_dirp = (struct dirent *)
> + this_dirp = (struct dirent64 *)
> ((char *) this_dirp + this_dirp->d_reclen);
> }
> if (result != 0)
> diff --git a/sysdeps/unix/sysv/linux/wordsize-64/getdents.c b/sysdeps/unix/sysv/linux/wordsize-64/getdents.c
> deleted file mode 100644
> index 5ea4c57..0000000
> --- a/sysdeps/unix/sysv/linux/wordsize-64/getdents.c
> +++ /dev/null
> @@ -1,4 +0,0 @@
> -#define __getdents64 __no___getdents64_decl
> -#include <sysdeps/unix/sysv/linux/getdents.c>
> -#undef __getdents64
> -weak_alias (__getdents, __getdents64);
> diff --git a/sysdeps/unix/sysv/linux/wordsize-64/getdents64.c b/sysdeps/unix/sysv/linux/wordsize-64/getdents64.c
> deleted file mode 100644
> index 0df2c8f..0000000
> --- a/sysdeps/unix/sysv/linux/wordsize-64/getdents64.c
> +++ /dev/null
> @@ -1 +0,0 @@
> -/* getdents64 is in getdents.c */
>
next prev parent reply other threads:[~2018-04-17 19:42 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-02 18:59 [PATCH 1/7] Assume O_DIRECTORY for opendir Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 7/7] Consolidate getdirentries{64} implementation Adhemerval Zanella
2018-04-25 19:49 ` Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 4/7] Consolidate Linux getdents{64} implementation Adhemerval Zanella
2018-03-09 18:10 ` Adhemerval Zanella
2018-04-17 19:42 ` Adhemerval Zanella [this message]
2018-04-19 17:29 ` Joseph Myers
2018-04-19 18:23 ` Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 6/7] Consolidate alphasort{64} and versionsort{64} implementation Adhemerval Zanella
2018-03-02 20:33 ` Joseph Myers
2018-03-06 11:28 ` Adhemerval Zanella
2018-04-23 18:01 ` Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 5/7] Consolidate scandir{at}{64} implementation Adhemerval Zanella
2018-04-20 13:50 ` Adhemerval Zanella
2018-04-20 15:30 ` Florian Weimer
2018-04-20 15:56 ` Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 3/7] Consolidate Linux readdir{64}{_r} implementation Adhemerval Zanella
2018-04-06 19:49 ` Adhemerval Zanella
2018-03-02 18:59 ` [PATCH 2/7] Define _DIRENT_MATCHES_DIRENT64 regardless Adhemerval Zanella
2018-03-02 19:30 ` Andreas Schwab
2018-04-02 13:59 ` [PATCH 1/7] Assume O_DIRECTORY for opendir Adhemerval Zanella
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