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-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c b/REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c
new file mode 100644
index 0000000000..b4c45cd3d4
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c
@@ -0,0 +1,79 @@
+/* Create new context.
+ Copyright (C) 2015-2017 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 <sysdep.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <ucontext.h>
+
+/* makecontext sets up a stack and the registers for the
+ user context. The stack looks like this:
+
+ +-----------------------+
+ | padding as required |
+ +-----------------------+
+ sp -> | parameters 5 to n |
+ +-----------------------+
+
+ The registers are set up like this:
+ r4--r7 : parameter 1 to 4
+ r16 : uc_link
+ sp : stack pointer.
+*/
+
+void
+__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
+{
+ extern void __startcontext (void);
+ unsigned long *sp;
+ va_list ap;
+ int i;
+
+ sp = (unsigned long *)
+ ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
+
+ /* Allocate stack arguments. */
+ sp -= argc < 4 ? 0 : argc - 4;
+
+ /* Keep the stack aligned. */
+ sp = (unsigned long*) (((uintptr_t) sp) & -4L);
+
+ /* Init version field. */
+ ucp->uc_mcontext.version = 2;
+ /* Keep uc_link in r16. */
+ ucp->uc_mcontext.regs[15] = (uintptr_t) ucp->uc_link;
+ /* Return address points to __startcontext(). */
+ ucp->uc_mcontext.regs[23] = (uintptr_t) &__startcontext;
+ /* Frame pointer is null. */
+ ucp->uc_mcontext.regs[24] = (uintptr_t) 0;
+ /* Restart in user-space starting at 'func'. */
+ ucp->uc_mcontext.regs[27] = (uintptr_t) func;
+ /* Set stack pointer. */
+ ucp->uc_mcontext.regs[28] = (uintptr_t) sp;
+
+ va_start (ap, argc);
+ for (i = 0; i < argc; ++i)
+ if (i < 4)
+ ucp->uc_mcontext.regs[i + 3] = va_arg (ap, unsigned long);
+ else
+ sp[i - 4] = va_arg (ap, unsigned long);
+
+ va_end (ap);
+}
+
+weak_alias (__makecontext, makecontext)