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-rw-r--r--sysdeps/unix/sysv/linux/hppa/makecontext.c99
1 files changed, 99 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/hppa/makecontext.c b/sysdeps/unix/sysv/linux/hppa/makecontext.c
new file mode 100644
index 0000000000..c8a1599d07
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/hppa/makecontext.c
@@ -0,0 +1,99 @@
+/* Create new context.
+   Copyright (C) 2008-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Helge Deller <deller@gmx.de>, 2008.
+
+   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 <libintl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sysdep.h>
+#include <ucontext.h>
+
+/* POSIX only supports integer arguments.  */
+
+/* Stack must be 64-byte aligned at all times.  */
+#define STACK_ALIGN 64
+/* Size of frame marker in unsigned long words.  */
+#define FRAME_SIZE_UL 8
+/* Size of frame marker in bytes.  */
+#define FRAME_SIZE_BYTES (8 * sizeof(unsigned long))
+/* Size of X arguments in bytes.  */
+#define ARGS(x) (x * sizeof(unsigned long))
+
+void
+__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
+{
+  unsigned long *sp, *osp;
+  va_list ap;
+  int i;
+
+  /* Create a 64-byte aligned frame to store args. Use ss_sp if
+     it is available, otherwise be robust and use the currently
+     saved stack pointer.  */
+  if (ucp->uc_stack.ss_sp && ucp->uc_stack.ss_size)
+    osp = (unsigned long *)ucp->uc_stack.ss_sp;
+  else
+    osp = (unsigned long *)ucp->uc_mcontext.sc_gr[30];
+
+  sp = (unsigned long *)((((unsigned long) osp)
+			   + FRAME_SIZE_BYTES + ARGS(argc) + STACK_ALIGN)
+			 & ~(STACK_ALIGN - 1));
+
+  /* Use new frame.  */
+  ucp->uc_mcontext.sc_gr[30] = ((unsigned long) sp);
+
+  /* Finish frame setup.  */
+  if (ucp->uc_link)
+    {
+      /* Returning to the next context and next frame.  */
+      sp[-4/sizeof(unsigned long)] = ucp->uc_link->uc_mcontext.sc_gr[30];
+      sp[-20/sizeof(unsigned long)] = ucp->uc_link->uc_mcontext.sc_gr[2];
+    }
+  else
+    {
+      /* This is the main context. No frame marker, and no return address.  */
+      sp[-4/sizeof(unsigned long)] = 0x0;
+      sp[-20/sizeof(unsigned long)] = 0x0;
+    }
+
+  /* Store address to jump to.  */
+  ucp->uc_mcontext.sc_gr[2] = (unsigned long) func;
+
+  /* Process arguments.  */
+  va_start (ap, argc);
+  for (i = 0; i < argc; ++i)
+    {
+      if (i < 4)
+	{
+	  ucp->uc_mcontext.sc_gr[26-i] = va_arg (ap, int);
+	  continue;
+	}
+
+      if ((i < 8) && (sizeof(unsigned long) == 8))
+	{
+	  /* 64bit: r19-r22 are arg7-arg4.  */
+	  ucp->uc_mcontext.sc_gr[22+4-i] = va_arg (ap, int);
+	  continue;
+	}
+
+      /* All other arguments go on the stack.  */
+      sp[-1 * (FRAME_SIZE_UL + 1 + i)] = va_arg (ap, int);
+    }
+  va_end (ap);
+}
+weak_alias(__makecontext, makecontext)