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# The 2.6 asm/stat.h for ARM has some rather unusual transmogrifications
# for big-endian running. This patch adds ARM specific code in xstatconv.c
# which deals with the 2.4->2.6 ABI change.
--- uClibc-0.9.27/libc/sysdeps/linux/common/xstatconv.c 2005-01-11 23:59:21.000000000 -0800
+++ uClibc-0.9.27/libc/sysdeps/linux/common/xstatconv.c 2005-06-05 11:03:56.742587966 -0700
@@ -18,7 +18,14 @@
02111-1307 USA.
Modified for uClibc by Erik Andersen <andersen@codepoet.org>
+ Further modified for ARMBE by John Bowler <jbowler@acm.org>
*/
+/* This is a copy of common/xstatconv.c with a fixup for the ABI
+ * (structure layout) change in ARM Linux 2.6 - this shifts the
+ * st_dev and st_rdev information from the start of the 8 byte
+ * space to the end on big-endian ARM (only). The code is unchanged
+ * on little endian.
+ */
#define _GNU_SOURCE
#define _LARGEFILE64_SOURCE
@@ -32,6 +39,84 @@
#include <sys/stat.h>
#include "xstatconv.h"
+/* Only for ARMEB and LFS. */
+#if defined(__ARMEB__) && defined(__UCLIBC_HAS_LFS__)
+/* stat64 (renamed) from 2.6.11.11. What happened here is that after
+ * Linux 2.4 the 2.4 unsigned short st_rdev and st_dev fields were
+ * lengthened to unsigned long long - causing the inclusion of at least
+ * some of the 0 padding bytes which followed them. On little endian
+ * this is fine because 2.4 did zero the pad bytes (I think) and the
+ * position of the data did not change. On big endian the change
+ * shifted the data to the end of the field. Someone noticed for the
+ * struct stat, and the armeb (big endian) case preserved the
+ * unsigned short (yuck), but no so for stat64 (maybe this was deliberate,
+ * but there is no evidence in the code of this.) Consequently a
+ * fixup is necessary for the stat64 case. The fixup here is to
+ * use the new structure when the change is detected. See below.
+ */
+struct __kernel_stat64_armeb {
+ /* This definition changes the layout on big-endian from that
+ * used in 2.4.31 - ABI change! Likewise for st_rdev.
+ */
+ unsigned long long st_dev;
+ unsigned char __pad0[4];
+ unsigned long __st_ino;
+ unsigned int st_mode;
+ unsigned int st_nlink;
+ unsigned long st_uid;
+ unsigned long st_gid;
+ unsigned long long st_rdev;
+ unsigned char __pad3[4];
+ long long st_size;
+ unsigned long st_blksize;
+ unsigned long __pad4;
+ unsigned long st_blocks;
+ unsigned long st_atime;
+ unsigned long st_atime_nsec;
+ unsigned long st_mtime;
+ unsigned long st_mtime_nsec;
+ unsigned long st_ctime;
+ unsigned long st_ctime_nsec;
+ unsigned long long st_ino;
+};
+
+/* This fixup only works so long as the old struct stat64 is no
+ * smaller than the new one - the caller of xstatconv uses the
+ * *old* struct, but the kernel writes the new one. CASSERT
+ * detects this at compile time.
+ */
+#define CASSERT(c) do switch (0) { case 0:; case (c):; } while (0)
+
+void __xstat64_conv_new(struct __kernel_stat64_armeb *kbuf, struct stat64 *buf)
+{
+ CASSERT(sizeof *kbuf <= sizeof (struct kernel_stat64));
+
+ /* Convert from new kernel version of `struct stat64'. */
+ buf->st_dev = kbuf->st_dev;
+ buf->st_ino = kbuf->st_ino;
+#ifdef _HAVE_STAT64___ST_INO
+ buf->__st_ino = kbuf->__st_ino;
+#endif
+ buf->st_mode = kbuf->st_mode;
+ buf->st_nlink = kbuf->st_nlink;
+ buf->st_uid = kbuf->st_uid;
+ buf->st_gid = kbuf->st_gid;
+ buf->st_rdev = kbuf->st_rdev;
+ buf->st_size = kbuf->st_size;
+ buf->st_blksize = kbuf->st_blksize;
+ buf->st_blocks = kbuf->st_blocks;
+ buf->st_atime = kbuf->st_atime;
+ buf->st_mtime = kbuf->st_mtime;
+ buf->st_ctime = kbuf->st_ctime;
+}
+#define _MAY_HAVE_NEW_STAT64 1
+#else
+#define _MAY_HAVE_NEW_STAT64 0
+#endif
+
+/* The following is taken verbatim from xstatconv.c apart from
+ * the addition of the _MAY_HAVE_NEW_STAT64 code.
+ */
void __xstat_conv(struct kernel_stat *kbuf, struct stat *buf)
{
/* Convert to current kernel version of `struct stat'. */
@@ -53,6 +138,19 @@
#if defined __UCLIBC_HAS_LFS__
void __xstat64_conv(struct kernel_stat64 *kbuf, struct stat64 *buf)
{
+# if _MAY_HAVE_NEW_STAT64
+ /* This relies on any device (0,0) not being mountable - i.e.
+ * it fails on Linux 2.4 if dev(0,0) is a mountable block file
+ * system and itself contains it's own device. That doesn't
+ * happen on Linux 2.4 so far as I can see, but even if it
+ * does the API only fails (even then) if 2.4 didn't set all
+ * of the pad bytes to 0 (and it does set them to zero.)
+ */
+ if (kbuf->st_dev == 0 && kbuf->st_rdev == 0) {
+ __xstat64_conv_new((struct __kernel_stat64_armeb*)kbuf, buf);
+ return;
+ }
+# endif
/* Convert to current kernel version of `struct stat64'. */
buf->st_dev = kbuf->st_dev;
buf->st_ino = kbuf->st_ino;
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