Add cygwin support

Fails a few tests

config-unix.mk

@@ -59,6 +59,14 @@ LINKFLAGS+=
 UV_OS_FILE=uv-freebsd.c
 endif
 
+ifneq (,$(findstring CYGWIN,$(uname_S)))
+EV_CONFIG=config_cygwin.h
+EIO_CONFIG=config_cygwin.h
+CPPFLAGS += -Ic-ares/config_cygwin
+LINKFLAGS+=
+UV_OS_FILE=uv-cygwin.c
+endif
+
 # Need _GNU_SOURCE for strdup?
 RUNNER_CFLAGS=$(CFLAGS) -D_GNU_SOURCE
 

uv-cygwin.c

@@ -0,0 +1,52 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+
+#include <stdint.h>
+#include <stddef.h>
+#include <time.h>
+
+#undef NANOSEC
+#define NANOSEC 1000000000
+
+
+uint64_t uv_hrtime() {
+  struct timespec ts;
+  clock_gettime(CLOCK_MONOTONIC, &ts);
+  return (ts.tv_sec * NANOSEC + ts.tv_nsec);
+}
+
+
+int uv_exepath(char* buffer, size_t* size) {
+  uint32_t usize;
+  int result;
+  char* path;
+  char* fullpath;
+
+  if (!buffer || !size) {
+    return -1;
+  }
+
+  *size = readlink("/proc/self/exe", buffer, *size - 1);
+  if (*size <= 0) return -1;
+  buffer[*size] = '\0';
+  return 0;
+}