diff --git a/util-internal.h b/util-internal.h
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--- /dev/null
+++ b/util-internal.h
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+/*
+ * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
+ *
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * 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.
+ */
+#ifndef _EVENT_UTIL_INTERNAL_H
+#define _EVENT_UTIL_INTERNAL_H
+
+#include "event2/event-config.h"
+#include <errno.h>
+
+/* For EVUTIL_ASSERT */
+#include "log-internal.h"
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef _EVENT_HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#include "event2/util.h"
+
+#include "ipv6-internal.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* If we need magic to say "inline", get it for free internally. */
+#ifdef _EVENT_inline
+#define inline _EVENT_inline
+#endif
+#ifdef _EVENT___func__
+#define __func__ _EVENT___func__
+#endif
+
+/* A good no-op to use in macro definitions. */
+#define _EVUTIL_NIL_STMT ((void)0)
+/* A no-op that tricks the compiler into thinking a condition is used while
+ * definitely not making any code for it.  Used to compile out asserts while
+ * avoiding "unused variable" warnings.  The "!" forces the compiler to
+ * do the sizeof() on an int, in case "condition" is a bitfield value.
+ */
+#define _EVUTIL_NIL_CONDITION(condition) do { \
+	(void)sizeof(!(condition));  \
+} while(0)
+
+/* Internal use only: macros to match patterns of error codes in a
+   cross-platform way.  We need these macros because of two historical
+   reasons: first, nonblocking IO functions are generally written to give an
+   error on the "blocked now, try later" case, so sometimes an error from a
+   read, write, connect, or accept means "no error; just wait for more
+   data," and we need to look at the error code.  Second, Windows defines
+   a different set of error codes for sockets. */
+
+#ifndef WIN32
+
+/* True iff e is an error that means a read/write operation can be retried. */
+#define EVUTIL_ERR_RW_RETRIABLE(e)				\
+	((e) == EINTR || (e) == EAGAIN)
+/* True iff e is an error that means an connect can be retried. */
+#define EVUTIL_ERR_CONNECT_RETRIABLE(e)			\
+	((e) == EINTR || (e) == EINPROGRESS)
+/* True iff e is an error that means a accept can be retried. */
+#define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
+	((e) == EINTR || (e) == EAGAIN || (e) == ECONNABORTED)
+
+/* True iff e is an error that means the connection was refused */
+#define EVUTIL_ERR_CONNECT_REFUSED(e)					\
+	((e) == ECONNREFUSED)
+
+#else
+
+#define EVUTIL_ERR_RW_RETRIABLE(e)					\
+	((e) == WSAEWOULDBLOCK ||					\
+	    (e) == WSAEINTR)
+
+#define EVUTIL_ERR_CONNECT_RETRIABLE(e)					\
+	((e) == WSAEWOULDBLOCK ||					\
+	    (e) == WSAEINTR ||						\
+	    (e) == WSAEINPROGRESS ||					\
+	    (e) == WSAEINVAL)
+
+#define EVUTIL_ERR_ACCEPT_RETRIABLE(e)			\
+	EVUTIL_ERR_RW_RETRIABLE(e)
+
+#define EVUTIL_ERR_CONNECT_REFUSED(e)					\
+	((e) == WSAECONNREFUSED)
+
+#endif
+
+#ifdef _EVENT_socklen_t
+#define socklen_t _EVENT_socklen_t
+#endif
+
+/* Arguments for shutdown() */
+#ifdef SHUT_RD
+#define EVUTIL_SHUT_RD SHUT_RD
+#else
+#define EVUTIL_SHUT_RD 0
+#endif
+#ifdef SHUT_WR
+#define EVUTIL_SHUT_WR SHUT_WR
+#else
+#define EVUTIL_SHUT_WR 1
+#endif
+#ifdef SHUT_BOTH
+#define EVUTIL_SHUT_BOTH SHUT_BOTH
+#else
+#define EVUTIL_SHUT_BOTH 2
+#endif
+
+/* Locale-independent replacements for some ctypes functions.  Use these
+ * when you care about ASCII's notion of character types, because you are about
+ * to send those types onto the wire.
+ */
+int EVUTIL_ISALPHA(char c);
+int EVUTIL_ISALNUM(char c);
+int EVUTIL_ISSPACE(char c);
+int EVUTIL_ISDIGIT(char c);
+int EVUTIL_ISXDIGIT(char c);
+int EVUTIL_ISPRINT(char c);
+int EVUTIL_ISLOWER(char c);
+int EVUTIL_ISUPPER(char c);
+char EVUTIL_TOUPPER(char c);
+char EVUTIL_TOLOWER(char c);
+
+/** Helper macro.  If we know that a given pointer points to a field in a
+    structure, return a pointer to the structure itself.  Used to implement
+    our half-baked C OO.  Example:
+
+    struct subtype {
+	int x;
+	struct supertype common;
+	int y;
+    };
+    ...
+    void fn(struct supertype *super) {
+	struct subtype *sub = EVUTIL_UPCAST(super, struct subtype, common);
+	...
+    }
+ */
+#define EVUTIL_UPCAST(ptr, type, field)				\
+	((type *)(((char*)(ptr)) - evutil_offsetof(type, field)))
+
+/* As open(pathname, flags, mode), except that the file is always opened with
+ * the close-on-exec flag set. (And the mode argument is mandatory.)
+ */
+int evutil_open_closeonexec(const char *pathname, int flags, unsigned mode);
+
+int evutil_read_file(const char *filename, char **content_out, size_t *len_out,
+    int is_binary);
+
+int evutil_socket_connect(evutil_socket_t *fd_ptr, struct sockaddr *sa, int socklen);
+
+int evutil_socket_finished_connecting(evutil_socket_t fd);
+
+int evutil_ersatz_socketpair(int, int , int, evutil_socket_t[]);
+
+int evutil_resolve(int family, const char *hostname, struct sockaddr *sa,
+    ev_socklen_t *socklen, int port);
+
+const char *evutil_getenv(const char *name);
+
+long _evutil_weakrand(void);
+
+/* Evaluates to the same boolean value as 'p', and hints to the compiler that
+ * we expect this value to be false. */
+#if defined(__GNUC__) && __GNUC__ >= 3         /* gcc 3.0 or later */
+#define EVUTIL_UNLIKELY(p) __builtin_expect(!!(p),0)
+#else
+#define EVUTIL_UNLIKELY(p) (p)
+#endif
+
+/* Replacement for assert() that calls event_errx on failure. */
+#ifdef NDEBUG
+#define EVUTIL_ASSERT(cond) _EVUTIL_NIL_CONDITION(cond)
+#define EVUTIL_FAILURE_CHECK(cond) 0
+#else
+#define EVUTIL_ASSERT(cond)						\
+	do {								\
+		if (EVUTIL_UNLIKELY(!(cond))) {				\
+			event_errx(_EVENT_ERR_ABORT,			\
+			    "%s:%d: Assertion %s failed in %s",		\
+			    __FILE__,__LINE__,#cond,__func__);		\
+			/* In case a user-supplied handler tries to */	\
+			/* return control to us, log and abort here. */	\
+			(void)fprintf(stderr,				\
+			    "%s:%d: Assertion %s failed in %s",		\
+			    __FILE__,__LINE__,#cond,__func__);		\
+			abort();					\
+		}							\
+	} while (0)
+#define EVUTIL_FAILURE_CHECK(cond) EVUTIL_UNLIKELY(cond)
+#endif
+
+#ifndef _EVENT_HAVE_STRUCT_SOCKADDR_STORAGE
+/* Replacement for sockaddr storage that we can use internally on platforms
+ * that lack it.  It is not space-efficient, but neither is sockaddr_storage.
+ */
+struct sockaddr_storage {
+	union {
+		struct sockaddr ss_sa;
+		struct sockaddr_in ss_sin;
+		struct sockaddr_in6 ss_sin6;
+		char ss_padding[128];
+	} ss_union;
+};
+#define ss_family ss_union.ss_sa.sa_family
+#endif
+
+/* Internal addrinfo error code.  This one is returned from only from
+ * evutil_getaddrinfo_common, when we are sure that we'll have to hit a DNS
+ * server. */
+#define EVUTIL_EAI_NEED_RESOLVE      -90002
+
+struct evdns_base;
+struct evdns_getaddrinfo_request;
+typedef struct evdns_getaddrinfo_request* (*evdns_getaddrinfo_fn)(
+    struct evdns_base *base,
+    const char *nodename, const char *servname,
+    const struct evutil_addrinfo *hints_in,
+    void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
+
+void evutil_set_evdns_getaddrinfo_fn(evdns_getaddrinfo_fn fn);
+
+struct evutil_addrinfo *evutil_new_addrinfo(struct sockaddr *sa,
+    ev_socklen_t socklen, const struct evutil_addrinfo *hints);
+struct evutil_addrinfo *evutil_addrinfo_append(struct evutil_addrinfo *first,
+    struct evutil_addrinfo *append);
+void evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo *hints);
+int evutil_getaddrinfo_common(const char *nodename, const char *servname,
+    struct evutil_addrinfo *hints, struct evutil_addrinfo **res, int *portnum);
+
+int evutil_getaddrinfo_async(struct evdns_base *dns_base,
+    const char *nodename, const char *servname,
+    const struct evutil_addrinfo *hints_in,
+    void (*cb)(int, struct evutil_addrinfo *, void *), void *arg);
+
+/** Return true iff sa is a looback address. (That is, it is 127.0.0.1/8, or
+ * ::1). */
+int evutil_sockaddr_is_loopback(const struct sockaddr *sa);
+
+
+/**
+    Formats a sockaddr sa into a string buffer of size outlen stored in out.
+    Returns a pointer to out.  Always writes something into out, so it's safe
+    to use the output of this function without checking it for NULL.
+ */
+const char *evutil_format_sockaddr_port(const struct sockaddr *sa, char *out, size_t outlen);
+
+long evutil_tv_to_msec(const struct timeval *tv);
+
+int evutil_hex_char_to_int(char c);
+
+#ifdef WIN32
+HANDLE evutil_load_windows_system_library(const TCHAR *library_name);
+#endif
+
+#ifndef EV_SIZE_FMT
+#if defined(_MSC_VER) || defined(__MINGW32__) || defined(__MINGW64__)
+#define EV_U64_FMT "%I64u"
+#define EV_I64_FMT "%I64d"
+#define EV_I64_ARG(x) ((__int64)(x))
+#define EV_U64_ARG(x) ((unsigned __int64)(x))
+#else
+#define EV_U64_FMT "%llu"
+#define EV_I64_FMT "%lld"
+#define EV_I64_ARG(x) ((long long)(x))
+#define EV_U64_ARG(x) ((unsigned long long)(x))
+#endif
+#endif
+
+#ifdef _WIN32
+#define EV_SOCK_FMT EV_I64_FMT
+#define EV_SOCK_ARG(x) EV_I64_ARG((x))
+#else
+#define EV_SOCK_FMT "%d"
+#define EV_SOCK_ARG(x) (x)
+#endif
+
+#if defined(__STDC__) && defined(__STDC_VERSION__)
+#if (__STDC_VERSION__ >= 199901L)
+#define EV_SIZE_FMT "%zu"
+#define EV_SSIZE_FMT "%zd"
+#define EV_SIZE_ARG(x) (x)
+#define EV_SSIZE_ARG(x) (x)
+#endif
+#endif
+
+#ifndef EV_SIZE_FMT
+#if (_EVENT_SIZEOF_SIZE_T <= _EVENT_SIZEOF_LONG)
+#define EV_SIZE_FMT "%lu"
+#define EV_SSIZE_FMT "%ld"
+#define EV_SIZE_ARG(x) ((unsigned long)(x))
+#define EV_SSIZE_ARG(x) ((long)(x))
+#else
+#define EV_SIZE_FMT EV_U64_FMT
+#define EV_SSIZE_FMT EV_I64_FMT
+#define EV_SIZE_ARG(x) EV_U64_ARG(x)
+#define EV_SSIZE_ARG(x) EV_I64_ARG(x)
+#endif
+#endif
+
+void evutil_memclear_(void *mem, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif