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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
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Prepare for radical source tree reorganization.zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage directory, REORG.TODO, except for files that will certainly still exist in their current form at top level when we're done (COPYING, COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which are moved to the new directory OldChangeLogs, instead), and the generated file INSTALL (which is just deleted; in the new order, there will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/nios2/makecontext.c')
-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)