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Diffstat (limited to 'lib/libc/riscv/gen/makecontext.c')
-rw-r--r--lib/libc/riscv/gen/makecontext.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/lib/libc/riscv/gen/makecontext.c b/lib/libc/riscv/gen/makecontext.c
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index 000000000000..3633a5dd66e1
--- /dev/null
+++ b/lib/libc/riscv/gen/makecontext.c
@@ -0,0 +1,91 @@
+/*-
+ * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
+ * All rights reserved.
+ *
+ * Portions of this software were developed by SRI International and the
+ * University of Cambridge Computer Laboratory under DARPA/AFRL contract
+ * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
+ *
+ * Portions of this software were developed by the University of Cambridge
+ * Computer Laboratory as part of the CTSRD Project, with support from the
+ * UK Higher Education Innovation Fund (HEIF).
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+
+#include <machine/riscvreg.h>
+
+#include <inttypes.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <ucontext.h>
+
+void _ctx_start(void);
+
+void
+ctx_done(ucontext_t *ucp)
+{
+
+ if (ucp->uc_link == NULL) {
+ exit(0);
+ } else {
+ setcontext((const ucontext_t *)ucp->uc_link);
+ abort();
+ }
+}
+
+__weak_reference(__makecontext, makecontext);
+
+void
+__makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
+{
+ struct gpregs *gp;
+ va_list ap;
+ int i;
+
+ /* A valid context is required. */
+ if (ucp == NULL)
+ return;
+
+ if ((argc < 0) || (argc > 8))
+ return;
+
+ gp = &ucp->uc_mcontext.mc_gpregs;
+
+ va_start(ap, argc);
+ /* Pass up to eight arguments in a0-7. */
+ for (i = 0; i < argc && i < 8; i++)
+ gp->gp_a[i] = va_arg(ap, uint64_t);
+ va_end(ap);
+
+ /* Set the stack */
+ gp->gp_sp = STACKALIGN(ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
+ /* Arrange for return via the trampoline code. */
+ gp->gp_sepc = (__register_t)_ctx_start;
+ gp->gp_s[0] = (__register_t)func;
+ gp->gp_s[1] = (__register_t)ucp;
+}