[[PATCH RFC 2] 32/63] Y2038: add function __fstat64_t64 (and __fxstat64_t64)

["Albert ARIBAUD (3ADEV)" <albert dot aribaud at 3adev dot fr>]

There is no Y2038-proof linux struct stat for now, so these
implementations just use the existing syscalls and convert from kernel
32-bit-time struct stat64 to GLIBC Y2038-ready struct __stat64_t64.
---
 include/sys/stat.h                 |  3 +++
 io/Versions                        |  1 +
 io/fstat64.c                       |  7 ++++++
 sysdeps/unix/sysv/linux/fxstat64.c | 50 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+)

diff --git a/include/sys/stat.h b/include/sys/stat.h
index 72f627f247..0d755c7398 100644
--- a/include/sys/stat.h
+++ b/include/sys/stat.h
@@ -38,6 +38,9 @@ extern int __mkdir (const char *__path, __mode_t __mode);
 libc_hidden_proto (__mkdir)
 extern int __mknod (const char *__path,
 		    __mode_t __mode, __dev_t __dev);
+extern int __fxstat64_t64 (int __ver, int __fildes,
+                           struct __stat64_t64 *__stat_buf);
+
 #if IS_IN (libc) || (IS_IN (rtld) && !defined NO_RTLD_HIDDEN)
 hidden_proto (__fxstat)
 hidden_proto (__fxstat64)
diff --git a/io/Versions b/io/Versions
index 98898cb9d5..a2857c7754 100644
--- a/io/Versions
+++ b/io/Versions
@@ -127,5 +127,6 @@ libc {
   }
   GLIBC_2.27 {
     copy_file_range;
+    __fxstat64_t64;
   }
 }
diff --git a/io/fstat64.c b/io/fstat64.c
index 0f4de02cee..60f8a74178 100644
--- a/io/fstat64.c
+++ b/io/fstat64.c
@@ -50,3 +50,10 @@ fstat64 (int fd, struct stat64 *buf)
 {
   return __fxstat64 (_STAT_VER, fd, buf);
 }
+
+int
+attribute_hidden
+__fstat64_t64 (int fd, struct __stat64_t64 *buf)
+{
+  return __fxstat64_t64 (_STAT_VER, fd, buf);
+}
diff --git a/sysdeps/unix/sysv/linux/fxstat64.c b/sysdeps/unix/sysv/linux/fxstat64.c
index 0d053897a0..705e47a120 100644
--- a/sysdeps/unix/sysv/linux/fxstat64.c
+++ b/sysdeps/unix/sysv/linux/fxstat64.c
@@ -51,3 +51,53 @@ hidden_ver (___fxstat64, __fxstat64)
 strong_alias (___fxstat64, __fxstat64)
 hidden_def (__fxstat64)
 #endif
+
+/* 64-bit time version */
+
+extern int __y2038_linux_support;
+
+int
+__fxstat64_t64 (int vers, int fd, struct __stat64_t64 *buf)
+{
+  int result;
+  struct stat64 st64;
+
+  if (__y2038_linux_support)
+    {
+      // TODO: use 64-bit syscalls when they become available
+    }
+
+  result = INLINE_SYSCALL (fstat64, 2, fd, &st64);
+#if defined _HAVE_STAT64___ST_INO && !__ASSUME_ST_INO_64_BIT
+  if (__builtin_expect (!result, 1) && st64.__st_ino != (__ino_t) st64.st_ino)
+    st64.st_ino = st64.__st_ino;
+#endif
+  if (!result)
+    {
+      buf->st_dev          = st64.st_dev;
+      //buf->__pad1		     = st64.__pad1;
+    
+#if defined _HAVE_STAT64___ST_INO
+      buf->__st_ino        = st64.__st_ino;
+#endif
+      buf->st_mode         = st64.st_mode;
+      buf->st_nlink        = st64.st_nlink;
+      buf->st_uid          = st64.st_uid;		 
+      buf->st_gid          = st64.st_gid;		 
+      buf->st_rdev         = st64.st_rdev;		 
+      buf->__pad2          = st64.__pad2;
+      buf->st_size         = st64.st_size;		 
+      buf->st_blksize      = st64.st_blksize;
+    
+      buf->st_blocks       = st64.st_blocks;		
+      buf->st_atim.tv_sec  = st64.st_atim.tv_sec;	
+      buf->st_atim.tv_nsec = st64.st_atim.tv_nsec;	
+      buf->st_mtim.tv_sec  = st64.st_mtim.tv_sec;	
+      buf->st_mtim.tv_nsec = st64.st_mtim.tv_nsec;	
+      buf->st_ctim.tv_sec  = st64.st_ctim.tv_sec;	
+      buf->st_ctim.tv_nsec = st64.st_ctim.tv_nsec;	
+    
+      buf->st_ino          = st64.st_ino;
+    }
+  return result;
+}
-- 
2.14.1