1 files changed, 81 insertions, 0 deletions
diff --git a/js/src/wasm/WasmSignalHandlers.h b/js/src/wasm/WasmSignalHandlers.h
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+++ b/js/src/wasm/WasmSignalHandlers.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ *
+ * Copyright 2014 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef wasm_signal_handlers_h
+#define wasm_signal_handlers_h
+
+#include "mozilla/Attributes.h"
+
+#if defined(XP_DARWIN)
+# include <mach/mach.h>
+#endif
+#include "threading/Thread.h"
+
+struct JSRuntime;
+
+namespace js {
+
+// Force any currently-executing asm.js/ion code to call HandleExecutionInterrupt.
+extern void
+InterruptRunningJitCode(JSRuntime* rt);
+
+namespace wasm {
+
+// Ensure the given JSRuntime is set up to use signals. Failure to enable signal
+// handlers indicates some catastrophic failure and creation of the runtime must
+// fail.
+MOZ_MUST_USE bool
+EnsureSignalHandlers(JSRuntime* rt);
+
+// Return whether signals can be used in this process for interrupts or
+// asm.js/wasm out-of-bounds.
+bool
+HaveSignalHandlers();
+
+#if defined(XP_DARWIN)
+// On OSX we are forced to use the lower-level Mach exception mechanism instead
+// of Unix signals. Mach exceptions are not handled on the victim's stack but
+// rather require an extra thread. For simplicity, we create one such thread
+// per JSRuntime (upon the first use of asm.js in the JSRuntime). This thread
+// and related resources are owned by AsmJSMachExceptionHandler which is owned
+// by JSRuntime.
+class MachExceptionHandler
+{
+    bool installed_;
+    js::Thread thread_;
+    mach_port_t port_;
+
+    void uninstall();
+
+  public:
+    MachExceptionHandler();
+    ~MachExceptionHandler() { uninstall(); }
+    mach_port_t port() const { return port_; }
+    bool installed() const { return installed_; }
+    bool install(JSRuntime* rt);
+};
+#endif
+
+// Test whether the given PC is within the innermost wasm activation. Return
+// false if it is not, or it cannot be determined.
+bool IsPCInWasmCode(void *pc);
+
+} // namespace wasm
+} // namespace js
+
+#endif // wasm_signal_handlers_h