diff --git a/.clang-format b/.clang-format
index 4059a1a7..5486a84a 100644
--- a/.clang-format
+++ b/.clang-format
@@ -68,7 +68,7 @@ IncludeCategories:
     Priority:        1
 IncludeIsMainRegex: '$'
 IndentCaseLabels: false
-IndentPPDirectives: None
+IndentPPDirectives: AfterHash
 IndentWidth:     2
 IndentWrappedFunctionNames: false
 JavaScriptQuotes: Leave
diff --git a/examples/asio-sv2.cc b/examples/asio-sv2.cc
index 8d2580ed..17ea02b9 100644
--- a/examples/asio-sv2.cc
+++ b/examples/asio-sv2.cc
@@ -36,10 +36,10 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #include <iostream>
 #include <string>
diff --git a/examples/client.c b/examples/client.c
index 5d210a28..2d3c4c5d 100644
--- a/examples/client.c
+++ b/examples/client.c
@@ -27,26 +27,26 @@
  * intentionally made simple.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <inttypes.h>
 #include <stdlib.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif /* HAVE_UNISTD_H */
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif /* HAVE_FCNTL_H */
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif /* HAVE_SYS_SOCKET_H */
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif /* HAVE_NETDB_H */
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif /* HAVE_NETINET_IN_H */
 #include <netinet/tcp.h>
 #include <poll.h>
diff --git a/examples/deflate.c b/examples/deflate.c
index eb713622..63f3ea15 100644
--- a/examples/deflate.c
+++ b/examples/deflate.c
@@ -23,7 +23,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* !HAVE_CONFIG_H */
 
 #include <stdio.h>
diff --git a/examples/libevent-client.c b/examples/libevent-client.c
index 216e7bc6..22b46da2 100644
--- a/examples/libevent-client.c
+++ b/examples/libevent-client.c
@@ -23,33 +23,33 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef __sgi
-#include <string.h>
-#define errx(exitcode, format, args...)                                        \
-  {                                                                            \
-    warnx(format, ##args);                                                     \
-    exit(exitcode);                                                            \
-  }
-#define warnx(format, args...) fprintf(stderr, format "\n", ##args)
+#  include <string.h>
+#  define errx(exitcode, format, args...)                                      \
+    {                                                                          \
+      warnx(format, ##args);                                                   \
+      exit(exitcode);                                                          \
+    }
+#  define warnx(format, args...) fprintf(stderr, format "\n", ##args)
 char *strndup(const char *s, size_t size);
 #endif
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <sys/types.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif /* HAVE_UNISTD_H */
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif /* HAVE_SYS_SOCKET_H */
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif /* HAVE_NETINET_IN_H */
 #include <netinet/tcp.h>
 #ifndef __sgi
-#include <err.h>
+#  include <err.h>
 #endif
 #include <signal.h>
 #include <string.h>
diff --git a/examples/libevent-server.c b/examples/libevent-server.c
index 541a7ee5..a5536175 100644
--- a/examples/libevent-server.c
+++ b/examples/libevent-server.c
@@ -23,41 +23,41 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef __sgi
-#define errx(exitcode, format, args...)                                        \
-  {                                                                            \
-    warnx(format, ##args);                                                     \
-    exit(exitcode);                                                            \
-  }
-#define warn(format, args...) warnx(format ": %s", ##args, strerror(errno))
-#define warnx(format, args...) fprintf(stderr, format "\n", ##args)
+#  define errx(exitcode, format, args...)                                      \
+    {                                                                          \
+      warnx(format, ##args);                                                   \
+      exit(exitcode);                                                          \
+    }
+#  define warn(format, args...) warnx(format ": %s", ##args, strerror(errno))
+#  define warnx(format, args...) fprintf(stderr, format "\n", ##args)
 #endif
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif /* HAVE_SYS_SOCKET_H */
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif /* HAVE_NETDB_H */
 #include <signal.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif /* HAVE_UNISTD_H */
 #include <sys/stat.h>
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif /* HAVE_FCNTL_H */
 #include <ctype.h>
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif /* HAVE_NETINET_IN_H */
 #include <netinet/tcp.h>
 #ifndef __sgi
-#include <err.h>
+#  include <err.h>
 #endif
 #include <string.h>
 #include <errno.h>
diff --git a/lib/includes/nghttp2/nghttp2.h b/lib/includes/nghttp2/nghttp2.h
index 3f9d39b1..4756ea64 100644
--- a/lib/includes/nghttp2/nghttp2.h
+++ b/lib/includes/nghttp2/nghttp2.h
@@ -28,7 +28,7 @@
 /* Define WIN32 when build target is Win32 API (borrowed from
    libcurl) */
 #if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32)
-#define WIN32
+#  define WIN32
 #endif
 
 #ifdef __cplusplus
@@ -40,9 +40,9 @@ extern "C" {
 /* MSVC < 2013 does not have inttypes.h because it is not C99
    compliant.  See compiler macros and version number in
    https://sourceforge.net/p/predef/wiki/Compilers/ */
-#include <stdint.h>
+#  include <stdint.h>
 #else /* !defined(_MSC_VER) || (_MSC_VER >= 1800) */
-#include <inttypes.h>
+#  include <inttypes.h>
 #endif /* !defined(_MSC_VER) || (_MSC_VER >= 1800) */
 #include <sys/types.h>
 #include <stdarg.h>
@@ -50,20 +50,20 @@ extern "C" {
 #include <nghttp2/nghttp2ver.h>
 
 #ifdef NGHTTP2_STATICLIB
-#define NGHTTP2_EXTERN
+#  define NGHTTP2_EXTERN
 #elif defined(WIN32)
-#ifdef BUILDING_NGHTTP2
-#define NGHTTP2_EXTERN __declspec(dllexport)
-#else /* !BUILDING_NGHTTP2 */
-#define NGHTTP2_EXTERN __declspec(dllimport)
-#endif /* !BUILDING_NGHTTP2 */
-#else  /* !defined(WIN32) */
-#ifdef BUILDING_NGHTTP2
-#define NGHTTP2_EXTERN __attribute__((visibility("default")))
-#else /* !BUILDING_NGHTTP2 */
-#define NGHTTP2_EXTERN
-#endif /* !BUILDING_NGHTTP2 */
-#endif /* !defined(WIN32) */
+#  ifdef BUILDING_NGHTTP2
+#    define NGHTTP2_EXTERN __declspec(dllexport)
+#  else /* !BUILDING_NGHTTP2 */
+#    define NGHTTP2_EXTERN __declspec(dllimport)
+#  endif /* !BUILDING_NGHTTP2 */
+#else    /* !defined(WIN32) */
+#  ifdef BUILDING_NGHTTP2
+#    define NGHTTP2_EXTERN __attribute__((visibility("default")))
+#  else /* !BUILDING_NGHTTP2 */
+#    define NGHTTP2_EXTERN
+#  endif /* !BUILDING_NGHTTP2 */
+#endif   /* !defined(WIN32) */
 
 /**
  * @macro
diff --git a/lib/nghttp2_buf.h b/lib/nghttp2_buf.h
index 9f484a22..06cce67a 100644
--- a/lib/nghttp2_buf.h
+++ b/lib/nghttp2_buf.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_BUF_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_callbacks.h b/lib/nghttp2_callbacks.h
index b607bbb5..61e51fa5 100644
--- a/lib/nghttp2_callbacks.h
+++ b/lib/nghttp2_callbacks.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_CALLBACKS_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_debug.h b/lib/nghttp2_debug.h
index 2e2cd0d1..cbb4dd57 100644
--- a/lib/nghttp2_debug.h
+++ b/lib/nghttp2_debug.h
@@ -26,18 +26,18 @@
 #define NGHTTP2_DEBUG_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
 
 #ifdef DEBUGBUILD
-#define DEBUGF(...) nghttp2_debug_vprintf(__VA_ARGS__)
+#  define DEBUGF(...) nghttp2_debug_vprintf(__VA_ARGS__)
 void nghttp2_debug_vprintf(const char *format, ...);
 #else
-#define DEBUGF(...)                                                            \
-  do {                                                                         \
-  } while (0)
+#  define DEBUGF(...)                                                          \
+    do {                                                                       \
+    } while (0)
 #endif
 
 #endif /* NGHTTP2_DEBUG_H */
diff --git a/lib/nghttp2_frame.h b/lib/nghttp2_frame.h
index cf04eec4..615bbf31 100644
--- a/lib/nghttp2_frame.h
+++ b/lib/nghttp2_frame.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_FRAME_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_hd.h b/lib/nghttp2_hd.h
index 760bfbc3..c64a1f2b 100644
--- a/lib/nghttp2_hd.h
+++ b/lib/nghttp2_hd.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HD_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_hd_huffman.h b/lib/nghttp2_hd_huffman.h
index 83323400..c6e3942e 100644
--- a/lib/nghttp2_hd_huffman.h
+++ b/lib/nghttp2_hd_huffman.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HD_HUFFMAN_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_helper.h b/lib/nghttp2_helper.h
index 4a32564f..b1f18ce5 100644
--- a/lib/nghttp2_helper.h
+++ b/lib/nghttp2_helper.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HELPER_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <string.h>
diff --git a/lib/nghttp2_http.h b/lib/nghttp2_http.h
index ac684c4d..dd057cdb 100644
--- a/lib/nghttp2_http.h
+++ b/lib/nghttp2_http.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HTTP_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_int.h b/lib/nghttp2_int.h
index 30cf7274..b23585cc 100644
--- a/lib/nghttp2_int.h
+++ b/lib/nghttp2_int.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_INT_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_map.h b/lib/nghttp2_map.h
index 21262488..f6e29e35 100644
--- a/lib/nghttp2_map.h
+++ b/lib/nghttp2_map.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_MAP_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_mem.h b/lib/nghttp2_mem.h
index 2d1bd6a0..f83dbcb8 100644
--- a/lib/nghttp2_mem.h
+++ b/lib/nghttp2_mem.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_MEM_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_net.h b/lib/nghttp2_net.h
index 587f4189..95ffee74 100644
--- a/lib/nghttp2_net.h
+++ b/lib/nghttp2_net.h
@@ -26,15 +26,15 @@
 #define NGHTTP2_NET_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif /* HAVE_ARPA_INET_H */
 
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif /* HAVE_NETINET_IN_H */
 
 #include <nghttp2/nghttp2.h>
@@ -44,11 +44,11 @@
    define inline functions for those function so that we don't have
    dependeny on that lib. */
 
-#ifdef _MSC_VER
-#define STIN static __inline
-#else
-#define STIN static inline
-#endif
+#  ifdef _MSC_VER
+#    define STIN static __inline
+#  else
+#    define STIN static inline
+#  endif
 
 STIN uint32_t htonl(uint32_t hostlong) {
   uint32_t res;
diff --git a/lib/nghttp2_npn.h b/lib/nghttp2_npn.h
index a481bde3..c6f1c04b 100644
--- a/lib/nghttp2_npn.h
+++ b/lib/nghttp2_npn.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_NPN_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_option.h b/lib/nghttp2_option.h
index c743e33b..29e72aa3 100644
--- a/lib/nghttp2_option.h
+++ b/lib/nghttp2_option.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_OPTION_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_outbound_item.h b/lib/nghttp2_outbound_item.h
index 89a8a926..b5f503a3 100644
--- a/lib/nghttp2_outbound_item.h
+++ b/lib/nghttp2_outbound_item.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_OUTBOUND_ITEM_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_pq.h b/lib/nghttp2_pq.h
index 71cf96a1..2d7b702a 100644
--- a/lib/nghttp2_pq.h
+++ b/lib/nghttp2_pq.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_PQ_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_priority_spec.h b/lib/nghttp2_priority_spec.h
index 98fac210..92ece822 100644
--- a/lib/nghttp2_priority_spec.h
+++ b/lib/nghttp2_priority_spec.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_PRIORITY_SPEC_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_queue.h b/lib/nghttp2_queue.h
index c7eb753c..a06fa6c7 100644
--- a/lib/nghttp2_queue.h
+++ b/lib/nghttp2_queue.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_QUEUE_H
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#  include "config.h"
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_rcbuf.h b/lib/nghttp2_rcbuf.h
index 29d1543e..6814e709 100644
--- a/lib/nghttp2_rcbuf.h
+++ b/lib/nghttp2_rcbuf.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_RCBUF_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_session.h b/lib/nghttp2_session.h
index 5fbc7155..5add50bc 100644
--- a/lib/nghttp2_session.h
+++ b/lib/nghttp2_session.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_SESSION_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_stream.h b/lib/nghttp2_stream.h
index da0e5d53..d1d5856d 100644
--- a/lib/nghttp2_stream.h
+++ b/lib/nghttp2_stream.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_STREAM_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_submit.h b/lib/nghttp2_submit.h
index 545388cf..74d702fb 100644
--- a/lib/nghttp2_submit.h
+++ b/lib/nghttp2_submit.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_SUBMIT_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/lib/nghttp2_version.c b/lib/nghttp2_version.c
index 8c5710d4..4211f2cf 100644
--- a/lib/nghttp2_version.c
+++ b/lib/nghttp2_version.c
@@ -23,7 +23,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <nghttp2/nghttp2.h>
diff --git a/src/HtmlParser.h b/src/HtmlParser.h
index fc2f2e57..1e846882 100644
--- a/src/HtmlParser.h
+++ b/src/HtmlParser.h
@@ -32,7 +32,7 @@
 
 #ifdef HAVE_LIBXML2
 
-#include <libxml/HTMLparser.h>
+#  include <libxml/HTMLparser.h>
 
 #endif // HAVE_LIBXML2
 
diff --git a/src/HttpServer.cc b/src/HttpServer.cc
index a6afa0c4..8dcf580e 100644
--- a/src/HttpServer.cc
+++ b/src/HttpServer.cc
@@ -26,23 +26,23 @@
 
 #include <sys/stat.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #include <netinet/tcp.h>
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif // HAVE_ARPA_INET_H
 
 #include <cassert>
@@ -64,7 +64,7 @@
 #include "template.h"
 
 #ifndef O_BINARY
-#define O_BINARY (0)
+#  define O_BINARY (0)
 #endif // O_BINARY
 
 namespace nghttp2 {
diff --git a/src/allocator.h b/src/allocator.h
index 32a74260..fa0de3ad 100644
--- a/src/allocator.h
+++ b/src/allocator.h
@@ -28,7 +28,7 @@
 #include "nghttp2_config.h"
 
 #ifndef _WIN32
-#include <sys/uio.h>
+#  include <sys/uio.h>
 #endif // !_WIN32
 
 #include <cassert>
diff --git a/src/app_helper.cc b/src/app_helper.cc
index 90c9fa8c..77fa5c24 100644
--- a/src/app_helper.cc
+++ b/src/app_helper.cc
@@ -24,19 +24,19 @@
  */
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #include <netinet/tcp.h>
 #include <poll.h>
diff --git a/src/app_helper.h b/src/app_helper.h
index 2e1ef53c..5424054f 100644
--- a/src/app_helper.h
+++ b/src/app_helper.h
@@ -30,7 +30,7 @@
 #include <cinttypes>
 #include <cstdlib>
 #ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
+#  include <sys/time.h>
 #endif // HAVE_SYS_TIME_H
 #include <poll.h>
 
diff --git a/src/base64_test.h b/src/base64_test.h
index 8fd0e494..8bdb84f8 100644
--- a/src/base64_test.h
+++ b/src/base64_test.h
@@ -26,7 +26,7 @@
 #define BASE64_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace nghttp2 {
diff --git a/src/buffer_test.h b/src/buffer_test.h
index abdc9879..6789aa39 100644
--- a/src/buffer_test.h
+++ b/src/buffer_test.h
@@ -26,7 +26,7 @@
 #define BUFFER_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace nghttp2 {
diff --git a/src/comp_helper.h b/src/comp_helper.h
index 0e48a75e..131ed21b 100644
--- a/src/comp_helper.h
+++ b/src/comp_helper.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_COMP_HELPER_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <jansson.h>
diff --git a/src/deflatehd.cc b/src/deflatehd.cc
index 2db89814..5d28e241 100644
--- a/src/deflatehd.cc
+++ b/src/deflatehd.cc
@@ -23,11 +23,11 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <getopt.h>
 
diff --git a/src/h2load.cc b/src/h2load.cc
index 229c73df..9e2592a8 100644
--- a/src/h2load.cc
+++ b/src/h2load.cc
@@ -27,12 +27,12 @@
 #include <getopt.h>
 #include <signal.h>
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #include <netinet/tcp.h>
 #include <sys/stat.h>
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 
 #include <cstdio>
@@ -58,7 +58,7 @@
 #include "template.h"
 
 #ifndef O_BINARY
-#define O_BINARY (0)
+#  define O_BINARY (0)
 #endif // O_BINARY
 
 using namespace nghttp2;
diff --git a/src/h2load.h b/src/h2load.h
index 4f6739d4..bde36e8d 100644
--- a/src/h2load.h
+++ b/src/h2load.h
@@ -29,10 +29,10 @@
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #include <sys/un.h>
 
diff --git a/src/http2_test.h b/src/http2_test.h
index bd7ddc05..0d63020e 100644
--- a/src/http2_test.h
+++ b/src/http2_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_HTTP2_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/inflatehd.cc b/src/inflatehd.cc
index 4f9bf5a0..9a159ad6 100644
--- a/src/inflatehd.cc
+++ b/src/inflatehd.cc
@@ -23,11 +23,11 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <getopt.h>
 
diff --git a/src/memchunk.h b/src/memchunk.h
index 6f76b492..d381e3cb 100644
--- a/src/memchunk.h
+++ b/src/memchunk.h
@@ -35,7 +35,7 @@ struct iovec {
   size_t iov_len; /* Length of data.  */
 };
 #else // !_WIN32
-#include <sys/uio.h>
+#  include <sys/uio.h>
 #endif // !_WIN32
 
 #include <cassert>
@@ -52,9 +52,9 @@ namespace nghttp2 {
 #define DEFAULT_WR_IOVCNT 16
 
 #if defined(IOV_MAX) && IOV_MAX < DEFAULT_WR_IOVCNT
-#define MAX_WR_IOVCNT IOV_MAX
+#  define MAX_WR_IOVCNT IOV_MAX
 #else // !defined(IOV_MAX) || IOV_MAX >= DEFAULT_WR_IOVCNT
-#define MAX_WR_IOVCNT DEFAULT_WR_IOVCNT
+#  define MAX_WR_IOVCNT DEFAULT_WR_IOVCNT
 #endif // !defined(IOV_MAX) || IOV_MAX >= DEFAULT_WR_IOVCNT
 
 template <size_t N> struct Memchunk {
diff --git a/src/memchunk_test.h b/src/memchunk_test.h
index 068f8255..7d677e78 100644
--- a/src/memchunk_test.h
+++ b/src/memchunk_test.h
@@ -26,7 +26,7 @@
 #define MEMCHUNK_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace nghttp2 {
diff --git a/src/network.h b/src/network.h
index 02dda099..45311d84 100644
--- a/src/network.h
+++ b/src/network.h
@@ -26,23 +26,23 @@
 #define NETWORK_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef _WIN32
-#include <ws2tcpip.h>
+#  include <ws2tcpip.h>
 #else // !_WIN32
-#include <sys/un.h>
+#  include <sys/un.h>
 #endif // !_WIN32
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif // HAVE_ARPA_INET_H
 
 namespace nghttp2 {
diff --git a/src/nghttp.cc b/src/nghttp.cc
index 58ee8804..7aaa65b7 100644
--- a/src/nghttp.cc
+++ b/src/nghttp.cc
@@ -26,13 +26,13 @@
 
 #include <sys/stat.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #include <netinet/tcp.h>
 #include <getopt.h>
@@ -50,7 +50,7 @@
 #include <openssl/err.h>
 
 #ifdef HAVE_JANSSON
-#include <jansson.h>
+#  include <jansson.h>
 #endif // HAVE_JANSSON
 
 #include "app_helper.h"
@@ -62,7 +62,7 @@
 #include "ssl_compat.h"
 
 #ifndef O_BINARY
-#define O_BINARY (0)
+#  define O_BINARY (0)
 #endif // O_BINARY
 
 namespace nghttp2 {
diff --git a/src/nghttp.h b/src/nghttp.h
index 3d970f03..120eb74d 100644
--- a/src/nghttp.h
+++ b/src/nghttp.h
@@ -29,10 +29,10 @@
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 
 #include <string>
diff --git a/src/nghttp2_config.h b/src/nghttp2_config.h
index 7fbd3657..8e6cd05f 100644
--- a/src/nghttp2_config.h
+++ b/src/nghttp2_config.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_CONFIG_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #endif // NGHTTP2_CONFIG_H
diff --git a/src/nghttp2_gzip.h b/src/nghttp2_gzip.h
index 2fa905a2..a40352c3 100644
--- a/src/nghttp2_gzip.h
+++ b/src/nghttp2_gzip.h
@@ -24,16 +24,16 @@
  */
 #ifndef NGHTTP2_GZIP_H
 
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif /* HAVE_CONFIG_H */
-#include <zlib.h>
+#  ifdef HAVE_CONFIG_H
+#    include <config.h>
+#  endif /* HAVE_CONFIG_H */
+#  include <zlib.h>
 
-#include <nghttp2/nghttp2.h>
+#  include <nghttp2/nghttp2.h>
 
-#ifdef __cplusplus
+#  ifdef __cplusplus
 extern "C" {
-#endif
+#  endif
 
 /**
  * @struct
@@ -115,8 +115,8 @@ int nghttp2_gzip_inflate(nghttp2_gzip *inflater, uint8_t *out,
  */
 int nghttp2_gzip_inflate_finished(nghttp2_gzip *inflater);
 
-#ifdef __cplusplus
+#  ifdef __cplusplus
 }
-#endif
+#  endif
 
 #endif /* NGHTTP2_GZIP_H */
diff --git a/src/nghttp2_gzip_test.h b/src/nghttp2_gzip_test.h
index 2defcdc8..8d554f72 100644
--- a/src/nghttp2_gzip_test.h
+++ b/src/nghttp2_gzip_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_GZIP_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #ifdef __cplusplus
diff --git a/src/nghttpd.cc b/src/nghttpd.cc
index b26aea2f..efa01103 100644
--- a/src/nghttpd.cc
+++ b/src/nghttpd.cc
@@ -25,11 +25,11 @@
 #include "nghttp2_config.h"
 
 #ifdef __sgi
-#define daemon _daemonize
+#  define daemon _daemonize
 #endif
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <signal.h>
 #include <getopt.h>
diff --git a/src/shrpx-unittest.cc b/src/shrpx-unittest.cc
index 7f9bd806..dd4fadf1 100644
--- a/src/shrpx-unittest.cc
+++ b/src/shrpx-unittest.cc
@@ -23,7 +23,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #include <stdio.h>
diff --git a/src/shrpx.cc b/src/shrpx.cc
index 003707a9..8f8e16cc 100644
--- a/src/shrpx.cc
+++ b/src/shrpx.cc
@@ -28,36 +28,36 @@
 #include <sys/wait.h>
 #include <sys/stat.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #include <sys/un.h>
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #include <signal.h>
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #include <netinet/tcp.h>
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif // HAVE_ARPA_INET_H
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <getopt.h>
 #ifdef HAVE_SYSLOG_H
-#include <syslog.h>
+#  include <syslog.h>
 #endif // HAVE_SYSLOG_H
 #ifdef HAVE_LIMITS_H
-#include <limits.h>
+#  include <limits.h>
 #endif // HAVE_LIMITS_H
 #ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
+#  include <sys/time.h>
 #endif // HAVE_SYS_TIME_H
 #include <sys/resource.h>
 #ifdef HAVE_LIBSYSTEMD
-#include <systemd/sd-daemon.h>
+#  include <systemd/sd-daemon.h>
 #endif // HAVE_LIBSYSTEMD
 
 #include <cinttypes>
@@ -131,16 +131,16 @@ constexpr auto ENV_ACCEPT_PREFIX = StringRef::from_lit("NGHTTPX_ACCEPT_");
 constexpr auto ENV_ORIG_PID = StringRef::from_lit("NGHTTPX_ORIG_PID");
 
 #ifndef _KERNEL_FASTOPEN
-#define _KERNEL_FASTOPEN
+#  define _KERNEL_FASTOPEN
 // conditional define for TCP_FASTOPEN mostly on ubuntu
-#ifndef TCP_FASTOPEN
-#define TCP_FASTOPEN 23
-#endif
+#  ifndef TCP_FASTOPEN
+#    define TCP_FASTOPEN 23
+#  endif
 
 // conditional define for SOL_TCP mostly on ubuntu
-#ifndef SOL_TCP
-#define SOL_TCP 6
-#endif
+#  ifndef SOL_TCP
+#    define SOL_TCP 6
+#  endif
 #endif
 
 // This configuration is fixed at the first startup of the main
@@ -1140,15 +1140,15 @@ int call_daemon() {
 #ifdef __sgi
   return _daemonize(0, 0, 0, 0);
 #else // !__sgi
-#ifdef HAVE_LIBSYSTEMD
+#  ifdef HAVE_LIBSYSTEMD
   if (sd_booted() && (getenv("NOTIFY_SOCKET") != nullptr)) {
     LOG(NOTICE) << "Daemonising disabled under systemd";
     chdir("/");
     return 0;
   }
-#endif // HAVE_LIBSYSTEMD
+#  endif // HAVE_LIBSYSTEMD
   return daemon(0, 0);
-#endif // !__sgi
+#endif   // !__sgi
 }
 } // namespace
 
diff --git a/src/shrpx.h b/src/shrpx.h
index c12064b8..60e873dd 100644
--- a/src/shrpx.h
+++ b/src/shrpx.h
@@ -26,20 +26,20 @@
 #define SHRPX_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 
 #include <cassert>
 
 #ifndef HAVE__EXIT
-#define nghttp2_Exit(status) _exit(status)
+#  define nghttp2_Exit(status) _exit(status)
 #else // HAVE__EXIT
-#define nghttp2_Exit(status) _Exit(status)
+#  define nghttp2_Exit(status) _Exit(status)
 #endif // HAVE__EXIT
 
 #define DIE() nghttp2_Exit(EXIT_FAILURE)
diff --git a/src/shrpx_accept_handler.cc b/src/shrpx_accept_handler.cc
index 3f41b831..01b64158 100644
--- a/src/shrpx_accept_handler.cc
+++ b/src/shrpx_accept_handler.cc
@@ -25,7 +25,7 @@
 #include "shrpx_accept_handler.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <cerrno>
diff --git a/src/shrpx_client_handler.cc b/src/shrpx_client_handler.cc
index 941e0e12..ea8cea16 100644
--- a/src/shrpx_client_handler.cc
+++ b/src/shrpx_client_handler.cc
@@ -25,13 +25,13 @@
 #include "shrpx_client_handler.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 
 #include <cerrno>
diff --git a/src/shrpx_config.cc b/src/shrpx_config.cc
index 5964dc49..bd4e0622 100644
--- a/src/shrpx_config.cc
+++ b/src/shrpx_config.cc
@@ -25,21 +25,21 @@
 #include "shrpx_config.h"
 
 #ifdef HAVE_PWD_H
-#include <pwd.h>
+#  include <pwd.h>
 #endif // HAVE_PWD_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #ifdef HAVE_SYSLOG_H
-#include <syslog.h>
+#  include <syslog.h>
 #endif // HAVE_SYSLOG_H
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <dirent.h>
 
diff --git a/src/shrpx_config.h b/src/shrpx_config.h
index d631a566..f08bbc0f 100644
--- a/src/shrpx_config.h
+++ b/src/shrpx_config.h
@@ -29,14 +29,14 @@
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #include <sys/un.h>
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif // HAVE_ARPA_INET_H
 #include <cinttypes>
 #include <cstdio>
diff --git a/src/shrpx_config_test.cc b/src/shrpx_config_test.cc
index 75319712..b970ccbc 100644
--- a/src/shrpx_config_test.cc
+++ b/src/shrpx_config_test.cc
@@ -25,7 +25,7 @@
 #include "shrpx_config_test.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <cstdlib>
diff --git a/src/shrpx_config_test.h b/src/shrpx_config_test.h
index 3e86a4be..a30de41a 100644
--- a/src/shrpx_config_test.h
+++ b/src/shrpx_config_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_CONFIG_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/shrpx_connection.cc b/src/shrpx_connection.cc
index eafda7e9..2269c63f 100644
--- a/src/shrpx_connection.cc
+++ b/src/shrpx_connection.cc
@@ -25,7 +25,7 @@
 #include "shrpx_connection.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <netinet/tcp.h>
 
@@ -817,11 +817,11 @@ int Connection::get_tcp_hint(TCPHint *hint) const {
   // For TLSv1.3, AES-GCM and CHACHA20_POLY1305 overhead are now 22
   // bytes (5 (header) + 1 (ContentType) + 16 (tag)).
   size_t tls_overhead;
-#ifdef TLS1_3_VERSION
+#  ifdef TLS1_3_VERSION
   if (SSL_version(tls.ssl) == TLS1_3_VERSION) {
     tls_overhead = 22;
   } else
-#endif // TLS1_3_VERSION
+#  endif // TLS1_3_VERSION
   {
     tls_overhead = 29;
   }
diff --git a/src/shrpx_connection_handler.cc b/src/shrpx_connection_handler.cc
index 19985aaf..89c8b4cc 100644
--- a/src/shrpx_connection_handler.cc
+++ b/src/shrpx_connection_handler.cc
@@ -25,7 +25,7 @@
 #include "shrpx_connection_handler.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <sys/types.h>
 #include <sys/wait.h>
@@ -254,15 +254,15 @@ int ConnectionHandler::create_worker_thread(size_t num) {
   cert_tree_ = tls::create_cert_lookup_tree();
   auto sv_ssl_ctx = tls::setup_server_ssl_context(
       all_ssl_ctx_, indexed_ssl_ctx_, cert_tree_.get()
-#ifdef HAVE_NEVERBLEED
+#  ifdef HAVE_NEVERBLEED
                                           ,
       nb_.get()
-#endif // HAVE_NEVERBLEED
+#  endif // HAVE_NEVERBLEED
   );
   auto cl_ssl_ctx = tls::setup_downstream_client_ssl_context(
-#ifdef HAVE_NEVERBLEED
+#  ifdef HAVE_NEVERBLEED
       nb_.get()
-#endif // HAVE_NEVERBLEED
+#  endif // HAVE_NEVERBLEED
   );
 
   if (cl_ssl_ctx) {
@@ -284,9 +284,9 @@ int ConnectionHandler::create_worker_thread(size_t num) {
 
     if (memcachedconf.tls) {
       session_cache_ssl_ctx = tls::create_ssl_client_context(
-#ifdef HAVE_NEVERBLEED
+#  ifdef HAVE_NEVERBLEED
           nb_.get(),
-#endif // HAVE_NEVERBLEED
+#  endif // HAVE_NEVERBLEED
           tlsconf.cacert, memcachedconf.cert_file,
           memcachedconf.private_key_file, nullptr);
       all_ssl_ctx_.push_back(session_cache_ssl_ctx);
@@ -299,11 +299,11 @@ int ConnectionHandler::create_worker_thread(size_t num) {
     auto worker = make_unique<Worker>(
         loop, sv_ssl_ctx, cl_ssl_ctx, session_cache_ssl_ctx, cert_tree_.get(),
         ticket_keys_, this, config->conn.downstream);
-#ifdef HAVE_MRUBY
+#  ifdef HAVE_MRUBY
     if (worker->create_mruby_context() != 0) {
       return -1;
     }
-#endif // HAVE_MRUBY
+#  endif // HAVE_MRUBY
 
     workers_.push_back(std::move(worker));
     worker_loops_.push_back(loop);
@@ -629,19 +629,19 @@ void ConnectionHandler::handle_ocsp_complete() {
       tls::verify_ocsp_response(ssl_ctx, ocsp_.resp.data(),
                                 ocsp_.resp.size()) == 0) {
 #ifndef OPENSSL_IS_BORINGSSL
-#ifdef HAVE_ATOMIC_STD_SHARED_PTR
+#  ifdef HAVE_ATOMIC_STD_SHARED_PTR
     std::atomic_store_explicit(
         &tls_ctx_data->ocsp_data,
         std::make_shared<std::vector<uint8_t>>(std::move(ocsp_.resp)),
         std::memory_order_release);
-#else  // !HAVE_ATOMIC_STD_SHARED_PTR
+#  else  // !HAVE_ATOMIC_STD_SHARED_PTR
     std::lock_guard<std::mutex> g(tls_ctx_data->mu);
     tls_ctx_data->ocsp_data =
         std::make_shared<std::vector<uint8_t>>(std::move(ocsp_.resp));
-#endif // !HAVE_ATOMIC_STD_SHARED_PTR
-#else  // OPENSSL_IS_BORINGSSL
+#  endif // !HAVE_ATOMIC_STD_SHARED_PTR
+#else    // OPENSSL_IS_BORINGSSL
     SSL_CTX_set_ocsp_response(ssl_ctx, ocsp_.resp.data(), ocsp_.resp.size());
-#endif // OPENSSL_IS_BORINGSSL
+#endif   // OPENSSL_IS_BORINGSSL
   }
 
   ++ocsp_.next;
diff --git a/src/shrpx_connection_handler.h b/src/shrpx_connection_handler.h
index 4c5ce743..65de76fa 100644
--- a/src/shrpx_connection_handler.h
+++ b/src/shrpx_connection_handler.h
@@ -29,7 +29,7 @@
 
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 
 #include <mutex>
@@ -37,7 +37,7 @@
 #include <vector>
 #include <random>
 #ifndef NOTHREADS
-#include <future>
+#  include <future>
 #endif // NOTHREADS
 
 #include <openssl/ssl.h>
@@ -45,7 +45,7 @@
 #include <ev.h>
 
 #ifdef HAVE_NEVERBLEED
-#include <neverbleed.h>
+#  include <neverbleed.h>
 #endif // HAVE_NEVERBLEED
 
 #include "shrpx_downstream_connection_pool.h"
diff --git a/src/shrpx_downstream.cc b/src/shrpx_downstream.cc
index 360a9a91..cdd33bb8 100644
--- a/src/shrpx_downstream.cc
+++ b/src/shrpx_downstream.cc
@@ -38,7 +38,7 @@
 #include "shrpx_http2_session.h"
 #include "shrpx_log.h"
 #ifdef HAVE_MRUBY
-#include "shrpx_mruby.h"
+#  include "shrpx_mruby.h"
 #endif // HAVE_MRUBY
 #include "util.h"
 #include "http2.h"
diff --git a/src/shrpx_downstream_test.h b/src/shrpx_downstream_test.h
index d9153ee5..ef06ea30 100644
--- a/src/shrpx_downstream_test.h
+++ b/src/shrpx_downstream_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_DOWNSTREAM_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/shrpx_http2_downstream_connection.cc b/src/shrpx_http2_downstream_connection.cc
index 70a4a055..7a2d5598 100644
--- a/src/shrpx_http2_downstream_connection.cc
+++ b/src/shrpx_http2_downstream_connection.cc
@@ -25,7 +25,7 @@
 #include "shrpx_http2_downstream_connection.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include "http-parser/http_parser.h"
diff --git a/src/shrpx_http2_session.cc b/src/shrpx_http2_session.cc
index 67039867..5fbe10ac 100644
--- a/src/shrpx_http2_session.cc
+++ b/src/shrpx_http2_session.cc
@@ -26,7 +26,7 @@
 
 #include <netinet/tcp.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <vector>
diff --git a/src/shrpx_http2_upstream.cc b/src/shrpx_http2_upstream.cc
index e67ea6ca..df78dfdf 100644
--- a/src/shrpx_http2_upstream.cc
+++ b/src/shrpx_http2_upstream.cc
@@ -39,7 +39,7 @@
 #include "shrpx_http2_session.h"
 #include "shrpx_log.h"
 #ifdef HAVE_MRUBY
-#include "shrpx_mruby.h"
+#  include "shrpx_mruby.h"
 #endif // HAVE_MRUBY
 #include "http2.h"
 #include "util.h"
diff --git a/src/shrpx_http_test.cc b/src/shrpx_http_test.cc
index 0fdcc93b..ba3fad97 100644
--- a/src/shrpx_http_test.cc
+++ b/src/shrpx_http_test.cc
@@ -25,7 +25,7 @@
 #include "shrpx_http_test.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <cstdlib>
diff --git a/src/shrpx_http_test.h b/src/shrpx_http_test.h
index 85d2947d..8bd8395d 100644
--- a/src/shrpx_http_test.h
+++ b/src/shrpx_http_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_HTTP_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/shrpx_https_upstream.cc b/src/shrpx_https_upstream.cc
index 452ec90d..556d1d85 100644
--- a/src/shrpx_https_upstream.cc
+++ b/src/shrpx_https_upstream.cc
@@ -39,7 +39,7 @@
 #include "shrpx_http2_session.h"
 #include "shrpx_log.h"
 #ifdef HAVE_MRUBY
-#include "shrpx_mruby.h"
+#  include "shrpx_mruby.h"
 #endif // HAVE_MRUBY
 #include "http2.h"
 #include "util.h"
diff --git a/src/shrpx_log.cc b/src/shrpx_log.cc
index d43b6fab..0fafc6c2 100644
--- a/src/shrpx_log.cc
+++ b/src/shrpx_log.cc
@@ -25,18 +25,18 @@
 #include "shrpx_log.h"
 
 #ifdef HAVE_SYSLOG_H
-#include <syslog.h>
+#  include <syslog.h>
 #endif // HAVE_SYSLOG_H
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #ifdef HAVE_INTTYPES_H
-#include <inttypes.h>
+#  include <inttypes.h>
 #endif // HAVE_INTTYPES_H
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #include <sys/wait.h>
 
diff --git a/src/shrpx_log_config.cc b/src/shrpx_log_config.cc
index a8fbe416..668f91ab 100644
--- a/src/shrpx_log_config.cc
+++ b/src/shrpx_log_config.cc
@@ -57,14 +57,14 @@ LogConfig::LogConfig()
 }
 
 #ifndef NOTHREADS
-#ifdef HAVE_THREAD_LOCAL
+#  ifdef HAVE_THREAD_LOCAL
 namespace {
 thread_local std::unique_ptr<LogConfig> config = make_unique<LogConfig>();
 } // namespace
 
 LogConfig *log_config() { return config.get(); }
 void delete_log_config() {}
-#else  // !HAVE_THREAD_LOCAL
+#  else  // !HAVE_THREAD_LOCAL
 namespace {
 pthread_key_t lckey;
 pthread_once_t lckey_once = PTHREAD_ONCE_INIT;
@@ -85,8 +85,8 @@ LogConfig *log_config() {
 }
 
 void delete_log_config() { delete log_config(); }
-#endif // !HAVE_THREAD_LOCAL
-#else  // NOTHREADS
+#  endif // !HAVE_THREAD_LOCAL
+#else    // NOTHREADS
 namespace {
 std::unique_ptr<LogConfig> config = make_unique<LogConfig>();
 } // namespace
@@ -94,7 +94,7 @@ std::unique_ptr<LogConfig> config = make_unique<LogConfig>();
 LogConfig *log_config() { return config.get(); }
 
 void delete_log_config() {}
-#endif // NOTHREADS
+#endif   // NOTHREADS
 
 void LogConfig::update_tstamp_millis(
     const std::chrono::system_clock::time_point &now) {
diff --git a/src/shrpx_memcached_connection.cc b/src/shrpx_memcached_connection.cc
index d087ac83..99ec1eb9 100644
--- a/src/shrpx_memcached_connection.cc
+++ b/src/shrpx_memcached_connection.cc
@@ -578,9 +578,9 @@ int MemcachedConnection::parse_packet() {
 #define DEFAULT_WR_IOVCNT 128
 
 #if defined(IOV_MAX) && IOV_MAX < DEFAULT_WR_IOVCNT
-#define MAX_WR_IOVCNT IOV_MAX
+#  define MAX_WR_IOVCNT IOV_MAX
 #else // !defined(IOV_MAX) || IOV_MAX >= DEFAULT_WR_IOVCNT
-#define MAX_WR_IOVCNT DEFAULT_WR_IOVCNT
+#  define MAX_WR_IOVCNT DEFAULT_WR_IOVCNT
 #endif // !defined(IOV_MAX) || IOV_MAX >= DEFAULT_WR_IOVCNT
 
 size_t MemcachedConnection::fill_request_buffer(struct iovec *iov,
diff --git a/src/shrpx_router_test.h b/src/shrpx_router_test.h
index 03b49d25..d39cb87b 100644
--- a/src/shrpx_router_test.h
+++ b/src/shrpx_router_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_ROUTER_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/shrpx_tls.cc b/src/shrpx_tls.cc
index 9f12f37a..74ca9e16 100644
--- a/src/shrpx_tls.cc
+++ b/src/shrpx_tls.cc
@@ -25,10 +25,10 @@
 #include "shrpx_tls.h"
 
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #include <netinet/tcp.h>
 #include <pthread.h>
@@ -46,7 +46,7 @@
 #include <openssl/rand.h>
 #include <openssl/dh.h>
 #ifndef OPENSSL_NO_OCSP
-#include <openssl/ocsp.h>
+#  include <openssl/ocsp.h>
 #endif // OPENSSL_NO_OCSP
 
 #include <nghttp2/nghttp2.h>
@@ -204,21 +204,21 @@ int servername_callback(SSL *ssl, int *al, void *arg) {
     for (auto ssl_ctx : ssl_ctx_list) {
       auto cert = SSL_CTX_get0_certificate(ssl_ctx);
 
-#if OPENSSL_1_1_API
+#  if OPENSSL_1_1_API
       auto pubkey = X509_get0_pubkey(cert);
-#else  // !OPENSSL_1_1_API
+#  else  // !OPENSSL_1_1_API
       auto pubkey = X509_get_pubkey(cert);
-#endif // !OPENSSL_1_1_API
+#  endif // !OPENSSL_1_1_API
 
       if (EVP_PKEY_base_id(pubkey) != EVP_PKEY_EC) {
         continue;
       }
 
-#if OPENSSL_1_1_API
+#  if OPENSSL_1_1_API
       auto eckey = EVP_PKEY_get0_EC_KEY(pubkey);
-#else  // !OPENSSL_1_1_API
+#  else  // !OPENSSL_1_1_API
       auto eckey = EVP_PKEY_get1_EC_KEY(pubkey);
-#endif // !OPENSSL_1_1_API
+#  endif // !OPENSSL_1_1_API
 
       if (eckey == nullptr) {
         continue;
@@ -227,10 +227,10 @@ int servername_callback(SSL *ssl, int *al, void *arg) {
       auto ecgroup = EC_KEY_get0_group(eckey);
       auto cert_curve = EC_GROUP_get_curve_name(ecgroup);
 
-#if !OPENSSL_1_1_API
+#  if !OPENSSL_1_1_API
       EC_KEY_free(eckey);
       EVP_PKEY_free(pubkey);
-#endif // !OPENSSL_1_1_API
+#  endif // !OPENSSL_1_1_API
 
       if (shared_curve == cert_curve) {
         SSL_set_SSL_CTX(ssl, ssl_ctx);
@@ -251,13 +251,13 @@ int servername_callback(SSL *ssl, int *al, void *arg) {
 namespace {
 std::shared_ptr<std::vector<uint8_t>>
 get_ocsp_data(TLSContextData *tls_ctx_data) {
-#ifdef HAVE_ATOMIC_STD_SHARED_PTR
+#  ifdef HAVE_ATOMIC_STD_SHARED_PTR
   return std::atomic_load_explicit(&tls_ctx_data->ocsp_data,
                                    std::memory_order_acquire);
-#else  // !HAVE_ATOMIC_STD_SHARED_PTR
+#  else  // !HAVE_ATOMIC_STD_SHARED_PTR
   std::lock_guard<std::mutex> g(tls_ctx_data->mu);
   return tls_ctx_data->ocsp_data;
-#endif // !HAVE_ATOMIC_STD_SHARED_PTR
+#  endif // !HAVE_ATOMIC_STD_SHARED_PTR
 }
 } // namespace
 
@@ -567,9 +567,9 @@ int alpn_select_proto_cb(SSL *ssl, const unsigned char **out,
 
 #if !LIBRESSL_IN_USE && OPENSSL_VERSION_NUMBER >= 0x10002000L
 
-#ifndef TLSEXT_TYPE_signed_certificate_timestamp
-#define TLSEXT_TYPE_signed_certificate_timestamp 18
-#endif // !TLSEXT_TYPE_signed_certificate_timestamp
+#  ifndef TLSEXT_TYPE_signed_certificate_timestamp
+#    define TLSEXT_TYPE_signed_certificate_timestamp 18
+#  endif // !TLSEXT_TYPE_signed_certificate_timestamp
 
 namespace {
 int sct_add_cb(SSL *ssl, unsigned int ext_type, unsigned int context,
@@ -629,7 +629,7 @@ int sct_parse_cb(SSL *ssl, unsigned int ext_type, unsigned int context,
 }
 } // namespace
 
-#if !OPENSSL_1_1_1_API
+#  if !OPENSSL_1_1_1_API
 
 namespace {
 int legacy_sct_add_cb(SSL *ssl, unsigned int ext_type,
@@ -654,8 +654,8 @@ int legacy_sct_parse_cb(SSL *ssl, unsigned int ext_type,
 }
 } // namespace
 
-#endif // !OPENSSL_1_1_1_API
-#endif // !LIBRESSL_IN_USE && OPENSSL_VERSION_NUMBER >= 0x10002000L
+#  endif // !OPENSSL_1_1_1_API
+#endif   // !LIBRESSL_IN_USE && OPENSSL_VERSION_NUMBER >= 0x10002000L
 
 #ifndef OPENSSL_NO_PSK
 namespace {
@@ -794,18 +794,18 @@ SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
   }
 
 #ifndef OPENSSL_NO_EC
-#if !LIBRESSL_LEGACY_API && OPENSSL_VERSION_NUMBER >= 0x10002000L
+#  if !LIBRESSL_LEGACY_API && OPENSSL_VERSION_NUMBER >= 0x10002000L
   if (SSL_CTX_set1_curves_list(ssl_ctx, tlsconf.ecdh_curves.c_str()) != 1) {
     LOG(FATAL) << "SSL_CTX_set1_curves_list " << tlsconf.ecdh_curves
                << " failed";
     DIE();
   }
-#if !defined(OPENSSL_IS_BORINGSSL) && !OPENSSL_1_1_API
+#    if !defined(OPENSSL_IS_BORINGSSL) && !OPENSSL_1_1_API
   // It looks like we need this function call for OpenSSL 1.0.2.  This
   // function was deprecated in OpenSSL 1.1.0 and BoringSSL.
   SSL_CTX_set_ecdh_auto(ssl_ctx, 1);
-#endif // !defined(OPENSSL_IS_BORINGSSL) && !OPENSSL_1_1_API
-#else  // LIBRESSL_LEGACY_API || OPENSSL_VERSION_NUBMER < 0x10002000L
+#    endif // !defined(OPENSSL_IS_BORINGSSL) && !OPENSSL_1_1_API
+#  else    // LIBRESSL_LEGACY_API || OPENSSL_VERSION_NUBMER < 0x10002000L
   // Use P-256, which is sufficiently secure at the time of this
   // writing.
   auto ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
@@ -816,8 +816,8 @@ SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
   }
   SSL_CTX_set_tmp_ecdh(ssl_ctx, ecdh);
   EC_KEY_free(ecdh);
-#endif // LIBRESSL_LEGACY_API || OPENSSL_VERSION_NUBMER < 0x10002000L
-#endif // OPENSSL_NO_EC
+#  endif   // LIBRESSL_LEGACY_API || OPENSSL_VERSION_NUBMER < 0x10002000L
+#endif     // OPENSSL_NO_EC
 
   if (!tlsconf.dh_param_file.empty()) {
     // Read DH parameters from file
@@ -939,7 +939,7 @@ SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
   // OpenSSL handles signed_certificate_timestamp extension specially,
   // and it lets custom handler to process the extension.
   if (!sct_data.empty()) {
-#if OPENSSL_1_1_1_API
+#  if OPENSSL_1_1_1_API
     // It is not entirely clear to me that SSL_EXT_CLIENT_HELLO is
     // required here.  sct_parse_cb is called without
     // SSL_EXT_CLIENT_HELLO being set.  But the passed context value
@@ -953,7 +953,7 @@ SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
                  << ERR_error_string(ERR_get_error(), nullptr);
       DIE();
     }
-#else  // !OPENSSL_1_1_1_API
+#  else  // !OPENSSL_1_1_1_API
     if (SSL_CTX_add_server_custom_ext(
             ssl_ctx, TLSEXT_TYPE_signed_certificate_timestamp,
             legacy_sct_add_cb, legacy_sct_free_cb, nullptr, legacy_sct_parse_cb,
@@ -962,7 +962,7 @@ SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
                  << ERR_error_string(ERR_get_error(), nullptr);
       DIE();
     }
-#endif // !OPENSSL_1_1_1_API
+#  endif // !OPENSSL_1_1_1_API
   }
 #endif // !LIBRESSL_IN_USE && OPENSSL_VERSION_NUMBER >= 0x10002000L
 
@@ -1893,11 +1893,11 @@ int verify_ocsp_response(SSL_CTX *ssl_ctx, const uint8_t *ocsp_resp,
     return -1;
   }
 
-#if OPENSSL_1_1_API
+#  if OPENSSL_1_1_API
   auto certid = OCSP_SINGLERESP_get0_id(sresp);
-#else  // !OPENSSL_1_1_API
+#  else  // !OPENSSL_1_1_API
   auto certid = sresp->certId;
-#endif // !OPENSSL_1_1_API
+#  endif // !OPENSSL_1_1_API
   assert(certid != nullptr);
 
   ASN1_INTEGER *serial;
@@ -1971,10 +1971,10 @@ StringRef get_x509_issuer_name(BlockAllocator &balloc, X509 *x) {
 }
 
 #ifdef WORDS_BIGENDIAN
-#define bswap64(N) (N)
+#  define bswap64(N) (N)
 #else /* !WORDS_BIGENDIAN */
-#define bswap64(N)                                                             \
-  ((uint64_t)(ntohl((uint32_t)(N))) << 32 | ntohl((uint32_t)((N) >> 32)))
+#  define bswap64(N)                                                           \
+    ((uint64_t)(ntohl((uint32_t)(N))) << 32 | ntohl((uint32_t)((N) >> 32)))
 #endif /* !WORDS_BIGENDIAN */
 
 StringRef get_x509_serial(BlockAllocator &balloc, X509 *x) {
diff --git a/src/shrpx_tls.h b/src/shrpx_tls.h
index f3ee63c2..1ca20330 100644
--- a/src/shrpx_tls.h
+++ b/src/shrpx_tls.h
@@ -36,7 +36,7 @@
 #include <ev.h>
 
 #ifdef HAVE_NEVERBLEED
-#include <neverbleed.h>
+#  include <neverbleed.h>
 #endif // HAVE_NEVERBLEED
 
 #include "network.h"
diff --git a/src/shrpx_tls_test.h b/src/shrpx_tls_test.h
index 40360db9..e9c69d00 100644
--- a/src/shrpx_tls_test.h
+++ b/src/shrpx_tls_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_TLS_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/shrpx_worker.cc b/src/shrpx_worker.cc
index 58019431..8b169d0a 100644
--- a/src/shrpx_worker.cc
+++ b/src/shrpx_worker.cc
@@ -25,7 +25,7 @@
 #include "shrpx_worker.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <memory>
@@ -37,7 +37,7 @@
 #include "shrpx_log_config.h"
 #include "shrpx_memcached_dispatcher.h"
 #ifdef HAVE_MRUBY
-#include "shrpx_mruby.h"
+#  include "shrpx_mruby.h"
 #endif // HAVE_MRUBY
 #include "util.h"
 #include "template.h"
diff --git a/src/shrpx_worker.h b/src/shrpx_worker.h
index a7a7773e..096dfca5 100644
--- a/src/shrpx_worker.h
+++ b/src/shrpx_worker.h
@@ -34,7 +34,7 @@
 #include <deque>
 #include <thread>
 #ifndef NOTHREADS
-#include <future>
+#  include <future>
 #endif // NOTHREADS
 
 #include <openssl/ssl.h>
diff --git a/src/shrpx_worker_process.cc b/src/shrpx_worker_process.cc
index 647c167d..f1c67726 100644
--- a/src/shrpx_worker_process.cc
+++ b/src/shrpx_worker_process.cc
@@ -26,7 +26,7 @@
 
 #include <sys/types.h>
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <sys/resource.h>
 #include <sys/wait.h>
diff --git a/src/shrpx_worker_test.cc b/src/shrpx_worker_test.cc
index d907b327..7c5c3299 100644
--- a/src/shrpx_worker_test.cc
+++ b/src/shrpx_worker_test.cc
@@ -25,7 +25,7 @@
 #include "shrpx_worker_test.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 
 #include <cstdlib>
diff --git a/src/shrpx_worker_test.h b/src/shrpx_worker_test.h
index c9bdfe0d..8ffa2f12 100644
--- a/src/shrpx_worker_test.h
+++ b/src/shrpx_worker_test.h
@@ -26,7 +26,7 @@
 #define SHRPX_WORKER_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/ssl_compat.h b/src/ssl_compat.h
index 777b83c9..9574b7cc 100644
--- a/src/ssl_compat.h
+++ b/src/ssl_compat.h
@@ -24,20 +24,20 @@
  */
 #ifndef OPENSSL_COMPAT_H
 
-#include <openssl/opensslv.h>
+#  include <openssl/opensslv.h>
 
-#if defined(LIBRESSL_VERSION_NUMBER)
-#define OPENSSL_1_1_API 0
-#define OPENSSL_1_1_1_API 0
-#define LIBRESSL_IN_USE 1
-#define LIBRESSL_LEGACY_API (LIBRESSL_VERSION_NUMBER < 0x20700000L)
-#define LIBRESSL_2_7_API (LIBRESSL_VERSION_NUMBER >= 0x20700000L)
-#else // !defined(LIBRESSL_VERSION_NUMBER)
-#define OPENSSL_1_1_API (OPENSSL_VERSION_NUMBER >= 0x1010000fL)
-#define OPENSSL_1_1_1_API (OPENSSL_VERSION_NUMBER >= 0x10101000L)
-#define LIBRESSL_IN_USE 0
-#define LIBRESSL_LEGACY_API 0
-#define LIBRESSL_2_7_API 0
-#endif // !defined(LIBRESSL_VERSION_NUMBER)
+#  if defined(LIBRESSL_VERSION_NUMBER)
+#    define OPENSSL_1_1_API 0
+#    define OPENSSL_1_1_1_API 0
+#    define LIBRESSL_IN_USE 1
+#    define LIBRESSL_LEGACY_API (LIBRESSL_VERSION_NUMBER < 0x20700000L)
+#    define LIBRESSL_2_7_API (LIBRESSL_VERSION_NUMBER >= 0x20700000L)
+#  else // !defined(LIBRESSL_VERSION_NUMBER)
+#    define OPENSSL_1_1_API (OPENSSL_VERSION_NUMBER >= 0x1010000fL)
+#    define OPENSSL_1_1_1_API (OPENSSL_VERSION_NUMBER >= 0x10101000L)
+#    define LIBRESSL_IN_USE 0
+#    define LIBRESSL_LEGACY_API 0
+#    define LIBRESSL_2_7_API 0
+#  endif // !defined(LIBRESSL_VERSION_NUMBER)
 
 #endif // OPENSSL_COMPAT_H
diff --git a/src/template_test.h b/src/template_test.h
index 1a5a85be..2c1448f3 100644
--- a/src/template_test.h
+++ b/src/template_test.h
@@ -26,7 +26,7 @@
 #define TEMPLATE_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace nghttp2 {
diff --git a/src/timegm.h b/src/timegm.h
index 4383fda1..56f9cc6c 100644
--- a/src/timegm.h
+++ b/src/timegm.h
@@ -26,7 +26,7 @@
 #define TIMEGM_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #ifdef __cplusplus
@@ -34,7 +34,7 @@ extern "C" {
 #endif /* __cplusplus */
 
 #ifdef HAVE_TIME_H
-#include <time.h>
+#  include <time.h>
 #endif // HAVE_TIME_H
 
 time_t nghttp2_timegm(struct tm *tm);
diff --git a/src/util.cc b/src/util.cc
index 485163f2..7bbad812 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -25,30 +25,30 @@
 #include "util.h"
 
 #ifdef HAVE_TIME_H
-#include <time.h>
+#  include <time.h>
 #endif // HAVE_TIME_H
 #include <sys/types.h>
 #ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
+#  include <sys/socket.h>
 #endif // HAVE_SYS_SOCKET_H
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 #include <sys/stat.h>
 #ifdef HAVE_FCNTL_H
-#include <fcntl.h>
+#  include <fcntl.h>
 #endif // HAVE_FCNTL_H
 #ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
+#  include <netinet/in.h>
 #endif // HAVE_NETINET_IN_H
 #ifdef _WIN32
-#include <ws2tcpip.h>
-#include <boost/date_time/posix_time/posix_time.hpp>
+#  include <ws2tcpip.h>
+#  include <boost/date_time/posix_time/posix_time.hpp>
 #else // !_WIN32
-#include <netinet/tcp.h>
+#  include <netinet/tcp.h>
 #endif // !_WIN32
 #ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
+#  include <arpa/inet.h>
 #endif // HAVE_ARPA_INET_H
 
 #include <cmath>
@@ -80,9 +80,9 @@ int nghttp2_inet_pton(int af, const char *src, void *dst) {
 namespace {
 // inet_pton-wrapper for Windows
 int nghttp2_inet_pton(int af, const char *src, void *dst) {
-#if _WIN32_WINNT >= 0x0600
+#  if _WIN32_WINNT >= 0x0600
   return InetPtonA(af, src, dst);
-#else
+#  else
   // the function takes a 'char*', so we need to make a copy
   char addr[INET6_ADDRSTRLEN + 1];
   strncpy(addr, src, sizeof(addr));
@@ -93,7 +93,7 @@ int nghttp2_inet_pton(int af, const char *src, void *dst) {
   if (WSAStringToAddress(addr, af, NULL, (LPSOCKADDR)dst, &size) == 0)
     return 1;
   return 0;
-#endif
+#  endif
 }
 } // namespace
 #endif // _WIN32
diff --git a/src/util.h b/src/util.h
index cc85b2c5..e6a4cf6e 100644
--- a/src/util.h
+++ b/src/util.h
@@ -28,11 +28,11 @@
 #include "nghttp2_config.h"
 
 #ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#  include <unistd.h>
 #endif // HAVE_UNISTD_H
 #include <getopt.h>
 #ifdef HAVE_NETDB_H
-#include <netdb.h>
+#  include <netdb.h>
 #endif // HAVE_NETDB_H
 
 #include <cmath>
diff --git a/src/util_test.h b/src/util_test.h
index bfc934c3..41ba9fe2 100644
--- a/src/util_test.h
+++ b/src/util_test.h
@@ -26,7 +26,7 @@
 #define UTIL_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif // HAVE_CONFIG_H
 
 namespace shrpx {
diff --git a/src/xsi_strerror.c b/src/xsi_strerror.c
index 1796b7dc..d008d4e2 100644
--- a/src/xsi_strerror.c
+++ b/src/xsi_strerror.c
@@ -26,11 +26,11 @@
 
 /* Make sure that we get XSI-compliant version of strerror_r */
 #ifdef _POSIX_C_SOURCE
-#undef _POSIX_C_SOURCE
+#  undef _POSIX_C_SOURCE
 #endif /* _POSIX_C_SOURCE */
 
 #ifdef _GNU_SOURCE
-#undef _GNU_SOURCE
+#  undef _GNU_SOURCE
 #endif /* _GNU_SOURCE */
 
 #include <string.h>
diff --git a/src/xsi_strerror.h b/src/xsi_strerror.h
index 9bb61659..32cadc34 100644
--- a/src/xsi_strerror.h
+++ b/src/xsi_strerror.h
@@ -26,7 +26,7 @@
 #define XSI_STRERROR_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <stddef.h>
diff --git a/tests/failmalloc.c b/tests/failmalloc.c
index 4d7376e4..6ca39165 100644
--- a/tests/failmalloc.c
+++ b/tests/failmalloc.c
@@ -23,7 +23,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <stdio.h>
diff --git a/tests/failmalloc_test.h b/tests/failmalloc_test.h
index c4306530..576932a7 100644
--- a/tests/failmalloc_test.h
+++ b/tests/failmalloc_test.h
@@ -26,7 +26,7 @@
 #define FAILMALLOC_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_session_send(void);
diff --git a/tests/main.c b/tests/main.c
index 4af7d419..41e52017 100644
--- a/tests/main.c
+++ b/tests/main.c
@@ -23,7 +23,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <stdio.h>
diff --git a/tests/malloc_wrapper.h b/tests/malloc_wrapper.h
index 62369d6f..a3a3dd79 100644
--- a/tests/malloc_wrapper.h
+++ b/tests/malloc_wrapper.h
@@ -26,7 +26,7 @@
 #define MALLOC_WRAPPER_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include <stdlib.h>
diff --git a/tests/nghttp2_buf_test.h b/tests/nghttp2_buf_test.h
index c37e5150..714b89fd 100644
--- a/tests/nghttp2_buf_test.h
+++ b/tests/nghttp2_buf_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_BUF_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_bufs_add(void);
diff --git a/tests/nghttp2_frame_test.h b/tests/nghttp2_frame_test.h
index 8c0d6d5b..488d710c 100644
--- a/tests/nghttp2_frame_test.h
+++ b/tests/nghttp2_frame_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_FRAME_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_frame_pack_headers(void);
diff --git a/tests/nghttp2_hd_test.h b/tests/nghttp2_hd_test.h
index ab5fcae6..858afe6d 100644
--- a/tests/nghttp2_hd_test.h
+++ b/tests/nghttp2_hd_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HD_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_hd_deflate(void);
diff --git a/tests/nghttp2_helper_test.h b/tests/nghttp2_helper_test.h
index 68bdb6f9..cca8122a 100644
--- a/tests/nghttp2_helper_test.h
+++ b/tests/nghttp2_helper_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_HELPER_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_adjust_local_window_size(void);
diff --git a/tests/nghttp2_map_test.h b/tests/nghttp2_map_test.h
index 9f2770a0..62ae54b3 100644
--- a/tests/nghttp2_map_test.h
+++ b/tests/nghttp2_map_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_MAP_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_map(void);
diff --git a/tests/nghttp2_npn_test.h b/tests/nghttp2_npn_test.h
index 9d85e649..f1c97631 100644
--- a/tests/nghttp2_npn_test.h
+++ b/tests/nghttp2_npn_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_NPN_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_npn(void);
diff --git a/tests/nghttp2_pq_test.h b/tests/nghttp2_pq_test.h
index 2ce16614..969662a9 100644
--- a/tests/nghttp2_pq_test.h
+++ b/tests/nghttp2_pq_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_PQ_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_pq(void);
diff --git a/tests/nghttp2_queue_test.h b/tests/nghttp2_queue_test.h
index eb4d5299..64f8ce85 100644
--- a/tests/nghttp2_queue_test.h
+++ b/tests/nghttp2_queue_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_QUEUE_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_queue(void);
diff --git a/tests/nghttp2_session_test.h b/tests/nghttp2_session_test.h
index 52d990c0..c06ad9aa 100644
--- a/tests/nghttp2_session_test.h
+++ b/tests/nghttp2_session_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_SESSION_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 void test_nghttp2_session_recv(void);
diff --git a/tests/nghttp2_stream_test.h b/tests/nghttp2_stream_test.h
index 16a1f0a1..ad7be640 100644
--- a/tests/nghttp2_stream_test.h
+++ b/tests/nghttp2_stream_test.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_STREAM_TEST_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #endif /* NGHTTP2_STREAM_TEST_H */
diff --git a/tests/nghttp2_test_helper.h b/tests/nghttp2_test_helper.h
index 135f6ed8..c66298a0 100644
--- a/tests/nghttp2_test_helper.h
+++ b/tests/nghttp2_test_helper.h
@@ -26,7 +26,7 @@
 #define NGHTTP2_TEST_HELPER_H
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#  include <config.h>
 #endif /* HAVE_CONFIG_H */
 
 #include "nghttp2_frame.h"