rpms/xfsdump
7
0
Fork 0
Code Issues Pull Requests Releases Activity
cde0019aec
xfsdump/xfsdump-getdents-ifdef-hell.patch
Troy Dawson 8704d8f1d8 RHEL 9.0.0 Alpha bootstrap 
The content of this branch was automatically imported from Fedora ELN
with the following as its source:
https://src.fedoraproject.org/rpms/xfsdump#4fe9e0d20cdda9617ef07340832416b7729e2b3d
2020-10-15 14:00:19 -07:00

215 lines
7.0 KiB
Diff
Raw Blame History

commit 9ed517b63df35876681e8883388fbf154afda0c1
Author: Kyle McMartin <kmcmarti@redhat.com>
Date: Tue Apr 8 10:33:57 2014 +1000
xfsdump: getdents.c: clean up ifdef-hell around sys_getdents
Remove the ifdef-hell imported from glibc around getdents64. Everything
since 2.4.1 supports things properly and this seems like a sensible
clean up, so lets just assume it exists and handle it by falling back
if not.
Additionally, if the old getdents syscall doesn't exist, just stub out
the actual syscall and return ENOSYS.
Signed-off-by: Kyle McMartin <kmcmarti@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/common/getdents.c b/common/getdents.c
index e9ba25a..49d0d03 100644
--- a/common/getdents.c
+++ b/common/getdents.c
@@ -35,44 +35,6 @@
#include <linux/posix_types.h>
-/* Copied from kernel-features.h for __ASSUME_GETDENTS64_SYSCALL */
-#ifndef __LINUX_KERNEL_VERSION
-/* We assume the worst; all kernels should be supported. */
-# define __LINUX_KERNEL_VERSION 0
-#endif
-/* The getdents64 syscall was introduced in 2.4.0-test7. We test for
- 2.4.1 for the earliest version we know the syscall is available. */
-#if __LINUX_KERNEL_VERSION >= 132097
-# define __ASSUME_GETDENTS64_SYSCALL 1
-#endif
-/* There are an infinite number of PA-RISC kernel versions numbered
- 2.4.0. But they've not really been released as such. We require
- and expect the final version here. */
-#ifdef __hppa__
-# define __ASSUME_GETDENTS64_SYSCALL 1
-#endif
-
-#ifndef __set_errno
-#define __set_errno(e) (errno = (e))
-#endif
-
-
-#ifdef __NR_getdents64
-# ifndef __ASSUME_GETDENTS64_SYSCALL
-# ifndef __GETDENTS
-/* The variable is shared between all *getdents* calls. */
-int __have_no_getdents64;
-# else
-extern int __have_no_getdents64;
-# endif
-# endif
-/* Earlier versions of glibc don't define SYS_getdents64 at all */
-# ifndef SYS_getdents64
-# define SYS_getdents64 __NR_getdents64
-# endif
-#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
@@ -97,11 +59,22 @@ struct kernel_dirent64
char d_name[256];
};
-#ifndef DIRENT_TYPE
-# define DIRENT_TYPE struct dirent
+#define DIRENT_SET_DP_INO(dp, value) (dp)->d_ino = (value)
+
+#define __set_errno(e) (errno = (e))
+
+int __have_no_getdents64;
+
+#ifdef __NR_getdents64
+# define __SYS_GETDENTS64(fd, buf, len) (syscall(SYS_getdents64, fd, buf, len))
+#else
+# define __SYS_GETDENTS64(fd, buf, len) ({ __set_errno(ENOSYS); -1; })
#endif
-#ifndef DIRENT_SET_DP_INO
-# define DIRENT_SET_DP_INO(dp, value) (dp)->d_ino = (value)
+
+#ifdef __NR_getdents
+# define __SYS_GETDENTS(fd, buf, len) (syscall(SYS_getdents, fd, buf, len))
+#else
+# define __SYS_GETDENTS(fd, buf, len) ({ __set_errno(ENOSYS); -1; })
#endif
/* The problem here is that we cannot simply read the next NBYTES
@@ -115,50 +88,43 @@ struct kernel_dirent64
int
getdents_wrap (int fd, char *buf, size_t nbytes)
{
- DIRENT_TYPE *dp;
+ struct dirent *dp;
off64_t last_offset = -1;
ssize_t retval;
-#ifdef __NR_getdents64
-# ifndef __ASSUME_GETDENTS64_SYSCALL
if (!__have_no_getdents64)
-# endif
{
-# ifndef __ASSUME_GETDENTS64_SYSCALL
int saved_errno = errno;
-# endif
char *kbuf = buf;
size_t kbytes = nbytes;
- if (offsetof (DIRENT_TYPE, d_name)
+ if (offsetof (struct dirent, d_name)
< offsetof (struct kernel_dirent64, d_name)
- && nbytes <= sizeof (DIRENT_TYPE))
+ && nbytes <= sizeof (struct dirent))
{
kbytes = nbytes + offsetof (struct kernel_dirent64, d_name)
- - offsetof (DIRENT_TYPE, d_name);
+ - offsetof (struct dirent, d_name);
kbuf = alloca(kbytes);
}
- retval = syscall(SYS_getdents64, fd, kbuf, kbytes);
-# ifndef __ASSUME_GETDENTS64_SYSCALL
- if (retval != -1 && errno != -EINVAL)
-# endif
+ retval = __SYS_GETDENTS64(fd, kbuf, kbytes);
+ if (retval != -1)
{
struct kernel_dirent64 *kdp;
const size_t size_diff = (offsetof (struct kernel_dirent64, d_name)
- - offsetof (DIRENT_TYPE, d_name));
+ - offsetof (struct dirent, d_name));
/* If the structure returned by the kernel is identical to what we
need, don't do any conversions. */
- if (offsetof (DIRENT_TYPE, d_name)
+ if (offsetof (struct dirent, d_name)
== offsetof (struct kernel_dirent64, d_name)
&& sizeof (dp->d_ino) == sizeof (kdp->d_ino)
&& sizeof (dp->d_off) == sizeof (kdp->d_off))
return retval;
- dp = (DIRENT_TYPE *)buf;
+ dp = (struct dirent *)buf;
kdp = (struct kernel_dirent64 *) kbuf;
while ((char *) kdp < kbuf + retval)
{
- const size_t alignment = __alignof__ (DIRENT_TYPE);
+ const size_t alignment = __alignof__ (struct dirent);
/* Since kdp->d_reclen is already aligned for the kernel
structure this may compute a value that is bigger
than necessary. */
@@ -194,41 +160,39 @@ getdents_wrap (int fd, char *buf, size_t nbytes)
memmove (dp->d_name, kdp->d_name,
old_reclen - offsetof (struct kernel_dirent64, d_name));
- dp = (DIRENT_TYPE *) ((char *) dp + new_reclen);
+ dp = (struct dirent *) ((char *) dp + new_reclen);
kdp = (struct kernel_dirent64 *) ((char *) kdp + old_reclen);
}
return (char *) dp - buf;
}
-# ifndef __ASSUME_GETDENTS64_SYSCALL
__set_errno (saved_errno);
__have_no_getdents64 = 1;
-# endif
}
-#endif
+
+ /* fallback to getdents */
{
size_t red_nbytes;
struct kernel_dirent *skdp, *kdp;
- const size_t size_diff = (offsetof (DIRENT_TYPE, d_name)
+ const size_t size_diff = (offsetof (struct dirent, d_name)
- offsetof (struct kernel_dirent, d_name));
red_nbytes = MIN (nbytes
- - ((nbytes / (offsetof (DIRENT_TYPE, d_name) + 14))
+ - ((nbytes / (offsetof (struct dirent, d_name) + 14))
* size_diff),
nbytes - size_diff);
- dp = (DIRENT_TYPE *) buf;
+ dp = (struct dirent *) buf;
skdp = kdp = alloca (red_nbytes);
- retval = syscall(SYS_getdents, fd, kdp, red_nbytes);
-
+ retval = __SYS_GETDENTS(fd, kdp, red_nbytes);
if (retval == -1)
return -1;
while ((char *) kdp < (char *) skdp + retval)
{
- const size_t alignment = __alignof__ (DIRENT_TYPE);
+ const size_t alignment = __alignof__ (struct dirent);
/* 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)
@@ -259,7 +223,7 @@ getdents_wrap (int fd, char *buf, size_t nbytes)
memcpy (dp->d_name, kdp->d_name,
kdp->d_reclen - offsetof (struct kernel_dirent, d_name));
- dp = (DIRENT_TYPE *) ((char *) dp + new_reclen);
+ dp = (struct dirent *) ((char *) dp + new_reclen);
kdp = (struct kernel_dirent *) (((char *) kdp) + kdp->d_reclen);
}
}
Reference in New Issue View Git Blame Copy Permalink