workaround to the signal on Windows

uvloop/loop.pxd

@@ -47,12 +47,8 @@ cdef class Loop:
         bint _thread_is_main
         bint _sigint_check
 
-        IF UNAME_SYSNAME == "Windows":
-            # TODO(iceboy): Signal equivalence on windows?
-            pass
-        ELSE:
-            SignalsStack py_signals
-            SignalsStack uv_signals
+        SignalsStack py_signals
+        SignalsStack uv_signals
         bint _executing_py_code
 
         object _task_factory
@@ -207,7 +203,6 @@ include "handles/udp.pxd"
 include "server.pxd"
 
 IF UNAME_SYSNAME == "Windows":
-    # TODO(iceboy): Signal equivalence on windows?
-    pass
+    include "os_signal_win.pxd"
 ELSE:
     include "os_signal.pxd"

uvloop/loop.pyx

@@ -73,18 +73,14 @@ cdef class Loop:
         self._timers = set()
         self._polls = dict()
 
-        IF UNAME_SYSNAME == "Windows":
-            # TODO(iceboy): Signal equivalence on windows?
-            pass
-        ELSE:
-            if MAIN_THREAD_ID == PyThread_get_thread_ident():  # XXX
-                self.py_signals = SignalsStack()
-                self.uv_signals = SignalsStack()
+        if MAIN_THREAD_ID == PyThread_get_thread_ident():  # XXX
+            self.py_signals = SignalsStack()
+            self.uv_signals = SignalsStack()
 
-                self.py_signals.save()
-            else:
-                self.py_signals = None
-                self.uv_signals = None
+            self.py_signals.save()
+        else:
+            self.py_signals = None
+            self.uv_signals = None
 
         self._executing_py_code = 0
 
@@ -223,12 +219,8 @@ cdef class Loop:
         self._stop(SystemExit())
 
     cdef _check_sigint(self):
-        IF UNAME_SYSNAME == "Windows":
-            # TODO(iceboy): __signal_set_sigint() on windows?
-            pass
-        ELSE:
-            self.uv_signals.save()
-            __signal_set_sigint()
+        self.uv_signals.save()
+        __signal_set_sigint()
 
     cdef _on_idle(self):
         cdef:
@@ -290,13 +282,9 @@ cdef class Loop:
     cdef __run(self, uv.uv_run_mode mode):
         global __main_loop__
 
-        IF UNAME_SYSNAME == "Windows":
-            # TODO(iceboy): Signal equivalence on windows?
-            pass
-        ELSE:
-            if self.py_signals is not None:
-                # self.py_signals is not None only for the main thread
-                __main_loop__ = self
+        if self.py_signals is not None:
+            # self.py_signals is not None only for the main thread
+            __main_loop__ = self
 
         self._executing_py_code = 0
         # Although every UVHandle holds a reference to the loop,
@@ -309,14 +297,10 @@ cdef class Loop:
         Py_DECREF(self)
         self._executing_py_code = 1
 
-        IF UNAME_SYSNAME == "Windows":
-            # TODO(iceboy): Signal equivalence on windows?
-            pass
-        ELSE:
-            if self.py_signals is not None:
-                # self.py_signals is not None only for the main thread
-                self.py_signals.restore()
-                __main_loop__ = None
+        if self.py_signals is not None:
+            # self.py_signals is not None only for the main thread
+            self.py_signals.restore()
+            __main_loop__ = None
 
         if err < 0:
             raise convert_error(err)
@@ -2409,8 +2393,7 @@ include "handles/udp.pyx"
 include "server.pyx"
 
 IF UNAME_SYSNAME == "Windows":
-    # TODO(iceboy): Signal equivalence on windows?
-    pass
+    include "os_signal_win.pyx"
 ELSE:
     include "os_signal.pyx"
 

uvloop/os_signal_win.pxd

@@ -0,0 +1,17 @@
+from libc.signal cimport sighandler_t
+
+
+cdef extern from "Python.h":
+    ctypedef void (*PyOS_sighandler_t)(int)
+
+    PyOS_sighandler_t   PyOS_getsig(int)
+    PyOS_sighandler_t   PyOS_setsig(int, PyOS_sighandler_t)
+
+
+cdef class SignalsStack:
+    cdef:
+        sighandler_t[MAX_SIG] signals
+        bint saved
+
+    cdef save(self)
+    cdef restore(self)

uvloop/os_signal_win.pyx

@@ -0,0 +1,57 @@
+from libc.signal cimport SIG_DFL, SIG_IGN, SIG_ERR, sighandler_t, signal, SIGINT
+
+
+cdef class SignalsStack:
+    def __cinit__(self):
+        self.saved = 0
+        for i in range(MAX_SIG):
+            self.signals[i] = NULL
+
+    cdef save(self):
+        cdef sighandler_t handler
+
+        for i in range(MAX_SIG):
+            handler = <sighandler_t>(PyOS_getsig(i))
+            if handler != SIG_ERR:
+                self.signals[i] = handler
+
+        self.saved = 1
+
+    cdef restore(self):
+        cdef:
+            sighandler_t sig
+
+        if not self.saved:
+            raise RuntimeError("SignalsStack.save() wasn't called")
+
+        for i in range(MAX_SIG):
+            if self.signals[i] == NULL:
+                continue
+
+            if PyOS_setsig(i, self.signals[i]) == SIG_ERR:
+                raise convert_error(-errno.errno)
+
+
+cdef void __signal_handler_sigint(int sig) nogil:
+    cdef sighandler_t handle
+
+    # We can run this method without GIL because there is no
+    # Python code here -- all '.' and '[]' operators work on
+    # C structs/pointers.
+
+    if sig != SIGINT or __main_loop__ is None:
+        return
+
+    if __main_loop__._executing_py_code and not __main_loop__._custom_sigint:
+        PyErr_SetInterrupt()  # void
+        return
+
+    if __main_loop__.uv_signals is not None:
+        handle = __main_loop__.uv_signals.signals[sig]
+        if handle is not NULL:
+            handle(sig)  # void
+
+
+cdef __signal_set_sigint():
+    if PyOS_setsig(SIGINT, __signal_handler_sigint) == SIG_ERR:
+        raise convert_error(-errno.errno)