[PATCH 18/27] [AARCH64] Add kernel_sigaction.h for AARCH64 ILP32

[Yury Norov]

From: Andrew Pinski <apinski@xxxxxxxxxx>

In ILP32, the sigaction struct is the same as AARCH64 so we need
the header file kernel_sigaction.h.  To allow for this to work,
we use a long long fields and then add extra casts when converting
between the user exposed struct and the kernel exposed struct.

* sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h: New file.
* sysdeps/unix/sysv/linux/aarch64/sigaction.c (__libc_sigaction):
Add cast here it is necessary.

Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx>
---
 sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h | 12 ++++++++++++
 sysdeps/unix/sysv/linux/aarch64/sigaction.c        | 10 ++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)
 create mode 100644 sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h

diff --git a/sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h b/sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h
new file mode 100644
index 0000000..7b3023b
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/aarch64/kernel_sigaction.h
@@ -0,0 +1,12 @@
+
+#define HAVE_SA_RESTORER
+
+/* This is the sigaction structure in aarch64 kernel.
+   Note the ILP32 struct uses the same struct as LP64
+   which is why the fields are 64bit in size. */
+struct kernel_sigaction {
+	unsigned long long k_sa_handler;
+	unsigned long long sa_flags;
+	unsigned long long sa_restorer;
+	sigset_t sa_mask;
+};
diff --git a/sysdeps/unix/sysv/linux/aarch64/sigaction.c b/sysdeps/unix/sysv/linux/aarch64/sigaction.c
index 3291924..40a327f 100644
--- a/sysdeps/unix/sysv/linux/aarch64/sigaction.c
+++ b/sysdeps/unix/sysv/linux/aarch64/sigaction.c
@@ -39,15 +39,17 @@ __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
 
   if (act)
     {
-      kact.k_sa_handler = act->sa_handler;
+      kact.k_sa_handler = (unsigned long long)(uintptr_t)act->sa_handler;
       memcpy (&kact.sa_mask, &act->sa_mask, sizeof (sigset_t));
       kact.sa_flags = act->sa_flags;
 #ifdef HAVE_SA_RESTORER
       if (kact.sa_flags & SA_RESTORER)
-	kact.sa_restorer = act->sa_restorer;
+	kact.sa_restorer = (unsigned long long)(uintptr_t)act->sa_restorer;
 #endif
     }
 
+  /* This is needed for ILP32 as the structures are two different sizes due to
+     using the LP64 structure.  */
   result = INLINE_SYSCALL (rt_sigaction, 4, sig,
 			   act ? &kact : NULL,
 			   oact ? &koact : NULL, _NSIG / 8);
@@ -55,11 +57,11 @@ __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
     {
       if (oact && result >= 0)
 	{
-	  oact->sa_handler = koact.k_sa_handler;
+	  oact->sa_handler = (void*)(uintptr_t)koact.k_sa_handler;
 	  memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (sigset_t));
 	  oact->sa_flags = koact.sa_flags;
 #ifdef HAVE_SA_RESTORER
-	  oact->sa_restorer = koact.sa_restorer;
+	  oact->sa_restorer = (void*)(uintptr_t)koact.sa_restorer;
 #endif
 	}
     }
-- 
2.7.4