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-rw-r--r--sysdeps/unix/sysv/linux/personality.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/personality.c b/sysdeps/unix/sysv/linux/personality.c
new file mode 100644
index 0000000000..6724f1b2a6
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/personality.c
@@ -0,0 +1,49 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/personality.h>
+#include <sysdep.h>
+
+extern __typeof (personality) __personality;
+
+int
+__personality (unsigned long persona)
+{
+#ifdef PERSONALITY_TRUNCATE_ARGUMENT
+  /* Starting with kernel commit v2.6.21-3117-g97dc32c, the type of
+     task_struct->pesonality is "unsigned int".
+     Starting with kernel commit v2.6.35-rc1-372-g485d527, the personality
+     syscall accepts "unsigned int" instead of "long unsigned int".
+     Inbetween, a personality argument that does not fit into "unsigned int"
+     would result to system call returning -EINVAL.
+     We explicitly truncate the personality argument to "unsigned int"
+     to eliminate the uncertainty.  */
+  persona = (unsigned int) persona;
+#endif
+
+  INTERNAL_SYSCALL_DECL (err);
+  long ret = INTERNAL_SYSCALL (personality, err, 1, persona);
+
+  /* Starting with kernel commit v2.6.29-6609-g11d06b2, the personality syscall
+     never fails.  However, 32-bit kernels might flag valid values as errors, so
+     we need to reverse the error setting.  We can't use the raw result as some
+     arches split the return/error values.  */
+  if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (ret, err)))
+    ret = -INTERNAL_SYSCALL_ERRNO (ret, err);
+  return ret;
+}
+weak_alias (__personality, personality)