From 5e5ee15db2364d090624733c3eadf874b31ef08d Mon Sep 17 00:00:00 2001
From: Zixing Liu <zixing.liu@canonical.com>
Date: Sun, 24 Mar 2024 10:52:15 +0100
Subject: [PATCH] preload: Fix building with _FILE_OFFSET_BITS

Unsetting `_FILE_OFFSET_BITS` causes time_t to be treated as 32-bit
instead of the 64-bit that we want with `-D_TIME_BITS=64`.

Fixes #216

Co-Authored-By: Steve Langasek <steve.langasek@canonical.com>
Co-Authored-By: Martin Pitt <mpitt@debian.org>
---
 src/libumockdev-preload.c | 32 +++++++++++++++++++++++++++++---
 1 file changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/libumockdev-preload.c b/src/libumockdev-preload.c
index 7e1ea6f..bed4774 100644
--- a/src/libumockdev-preload.c
+++ b/src/libumockdev-preload.c
@@ -22,12 +22,30 @@
  * along with umockdev; If not, see <http://www.gnu.org/licenses/>.
  */
 
-/* override -D_FILE_OFFSET_BITS, it breaks us */
-#undef _FILE_OFFSET_BITS
-
 /* for getting stat64 */
 #define _GNU_SOURCE
 
+#include <features.h>
+
+#ifdef __GLIBC__
+/* Remove gcc asm aliasing so that our interposed symbols work as expected */
+#include <sys/cdefs.h>
+
+#include <stddef.h>
+extern int __REDIRECT_NTH (__ttyname_r_alias, (int __fd, char *__buf,
+                                               size_t __buflen), ttyname_r);
+
+#ifdef __REDIRECT
+#undef __REDIRECT
+#endif
+#define __REDIRECT(name, proto, alias) name proto
+#ifdef __REDIRECT_NTH
+#undef __REDIRECT_NTH
+#endif
+#define __REDIRECT_NTH(name, proto, alias) name proto __THROW
+
+#endif /* __GLIBC__ */
+
 #include <assert.h>
 #include <errno.h>
 #include <dirent.h>
@@ -63,6 +81,14 @@
 #include "utils.h"
 #include "ioctl_tree.h"
 
+#ifdef __GLIBC__
+/* Fixup for making a mess with __REDIRECT above */
+#ifdef __USE_TIME_BITS64
+#define clock_gettime __clock_gettime64
+extern int clock_gettime(clockid_t clockid, struct timespec *tp);
+#endif
+#endif
+
 /* fix missing O_TMPFILE on some systems */
 #ifndef O_TMPFILE
 #define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)