2 files changed, 104 insertions, 1 deletions

diff --git a/lib/libc/alpha/gen/Makefile.inc b/lib/libc/alpha/gen/Makefile.inc
index 4d0796cf2905..39292c470dfa 100644
--- a/lib/libc/alpha/gen/Makefile.inc
+++ b/lib/libc/alpha/gen/Makefile.inc
@@ -8,7 +8,7 @@ SRCS+=	sigsetjmp.S
 SRCS+=	__divqu.S __divq.S __divlu.S __divl.S
 SRCS+=	__remqu.S __remq.S __remlu.S __reml.S
 SRCS+=	rfork_thread.S
-SRCS+=	_ctx_start.S makecontext.c
+SRCS+=	_ctx_start.S makecontext.c signalcontext.c
 
 CLEANFILES+=	__divqu.S __divq.S __divlu.S __divl.S
 CLEANFILES+=	__remqu.S __remq.S __remlu.S __reml.S
diff --git a/lib/libc/alpha/gen/signalcontext.c b/lib/libc/alpha/gen/signalcontext.c
new file mode 100644
index 000000000000..a3f639719594
--- /dev/null
+++ b/lib/libc/alpha/gen/signalcontext.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2003 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * 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 ``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 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 <sys/ucontext.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <strings.h>
+
+typedef void (*handler_t)(uint64_t, uint64_t, uint64_t);
+
+/* Prototypes */
+static void ctx_wrapper(ucontext_t *ucp, handler_t func, uint64_t *args);
+
+__weak_reference(__signalcontext, signalcontext);
+
+int
+__signalcontext(ucontext_t *ucp, int sig, __sighandler_t *func)
+{
+	uint64_t *args;
+	siginfo_t *sig_si;
+	ucontext_t *sig_uc;
+	uint64_t sp;
+
+	/* Bail out if we don't have a valid ucontext pointer. */
+	if (ucp == NULL)
+		abort();
+
+	/*
+	 * Build a signal frame and copy the arguments of signal handler
+	 * 'func' onto the stack. We only need 3 arguments, but we
+	 * create room for 4 so that we are 16-byte aligned.
+	 */
+	sp = (ucp->uc_mcontext.mc_regs[FRAME_SP] - sizeof(ucontext_t)) & ~15UL;
+	sig_uc = (ucontext_t *)sp;
+	bcopy(ucp, sig_uc, sizeof(*sig_uc));
+	sp = (sp - sizeof(siginfo_t)) & ~15UL;
+	sig_si = (siginfo_t *)sp;
+	bzero(sig_si, sizeof(*sig_si));
+	sig_si->si_signo = sig;
+	sp -= 4 * sizeof(uint64_t);
+	args = (uint64_t *)sp;
+	args[0] = sig;
+	args[1] = (intptr_t)sig_si;
+	args[2] = (intptr_t)sig_uc;
+	args[3] = 0;
+
+	/*
+	 * Setup the ucontext of the signal handler.
+	 */
+	bzero(&ucp->uc_mcontext, sizeof(ucp->uc_mcontext));
+	ucp->uc_link = sig_uc;
+	sigdelset(&ucp->uc_sigmask, sig);
+
+	ucp->uc_mcontext.mc_format = _MC_REV0_TRAPFRAME;
+	ucp->uc_mcontext.mc_regs[FRAME_A0] = (register_t)ucp;
+	ucp->uc_mcontext.mc_regs[FRAME_A1] = (register_t)func;
+	ucp->uc_mcontext.mc_regs[FRAME_A1] = (register_t)args;
+	ucp->uc_mcontext.mc_regs[FRAME_SP] = (register_t)sp;
+	ucp->uc_mcontext.mc_regs[FRAME_PC] = (register_t)ctx_wrapper;
+	ucp->uc_mcontext.mc_regs[FRAME_RA] = (register_t)ctx_wrapper;
+	ucp->uc_mcontext.mc_regs[FRAME_T12] = (register_t)ctx_wrapper;
+	return (0);
+}
+
+static void
+ctx_wrapper(ucontext_t *ucp, handler_t func, uint64_t *args)
+{
+
+	(*func)(args[0], args[1], args[2]);
+	if (ucp->uc_link == NULL)
+		exit(0);
+	setcontext((const ucontext_t *)ucp->uc_link);
+	/* should never get here */
+	abort();
+	/* NOTREACHED */
+}