[wasm] Initial signal handler

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 5bb470a2ae3129c5d3d55941e7016e8ae41bf7e0..f2eba4d29af1514cf5cbe7fe633e4ec6896eebc3 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -7649,6 +7649,35 @@ class V8_EXPORT V8 {
    */
   static void ShutdownPlatform();
 
+#if V8_OS_LINUX && V8_TARGET_ARCH_X64
+  /**
+   * Given the V8 signal handler a chance to handle a fault.

[ahaas, 2017/02/20 09:27:23]

"Give" I guess

[Eric Holk, 2017/02/23 02:16:55]

Done.

+   *
+   * This function determines whether a memory access violation can be recovered
+   * by V8. If so, it will return true and modify context to return to a code
+   * fragment that can recover from the fault. Otherwise, TryHandleSignal will
+   * return true.

[ahaas, 2017/02/20 09:27:23]

return false;

[Eric Holk, 2017/02/23 02:16:55]

Done.

+   *
+   * The parameters to this function correspond to those passed to a Linux
+   * signal handler.
+   *
+   * \param signum The signal number.

[ahaas, 2017/02/20 09:27:23]

I would still prefer the name signal_number

[Eric Holk, 2017/02/23 02:16:55]

Done.

+   *
+   * \param info A pointer to the siginfo_t structure provided to the signal
+   * handler.
+   *
+   * \param context The third argument passed to the Linux signal handler, which
+   * points to a ucontext_t structure.
+   */
+  static bool TryHandleSignal(int signum, void* info, void* context);
+#endif  // V8_OS_LINUX
+
+  /**
+   * Enable the default signal handler rather than using one provided by the
+   * embedder.
+   */
+  static bool RegisterDefaultSignalHandler();
+
  private:
   V8();