Guard headers tool.
diff --git a/src/core/transport/chttp2/alpn.h b/src/core/transport/chttp2/alpn.h
index 796f514..fcbefc0 100644
--- a/src/core/transport/chttp2/alpn.h
+++ b/src/core/transport/chttp2/alpn.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_ALPN_H_
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_ALPN_H_
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_ALPN_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_ALPN_H
 
 #include <string.h>
 
@@ -46,4 +46,4 @@
  * grpc_chttp2_num_alpn_versions()) */
 const char *grpc_chttp2_get_alpn_version_index(size_t i);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_ALPN_H_ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_ALPN_H */
diff --git a/src/core/transport/chttp2/bin_encoder.h b/src/core/transport/chttp2/bin_encoder.h
index 2368fdd..9c88ac9 100644
--- a/src/core/transport/chttp2/bin_encoder.h
+++ b/src/core/transport/chttp2/bin_encoder.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_BIN_ENCODER_H_
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_BIN_ENCODER_H_
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_BIN_ENCODER_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_BIN_ENCODER_H
 
 #include <grpc/support/slice.h>
 
@@ -53,4 +53,4 @@
 
 int grpc_is_binary_header(const char *key, size_t length);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_BIN_ENCODER_H_ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_BIN_ENCODER_H */
diff --git a/src/core/transport/chttp2/frame.h b/src/core/transport/chttp2/frame.h
index 733dd5e..fbb9419 100644
--- a/src/core/transport/chttp2/frame.h
+++ b/src/core/transport/chttp2/frame.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_H
 
 #include <grpc/support/port_platform.h>
 #include <grpc/support/slice.h>
@@ -77,4 +77,4 @@
 #define GRPC_CHTTP2_DATA_FLAG_PADDED 8
 #define GRPC_CHTTP2_FLAG_HAS_PRIORITY 0x20
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_H */
diff --git a/src/core/transport/chttp2/frame_data.h b/src/core/transport/chttp2/frame_data.h
index 4d05a5f..24e557a 100644
--- a/src/core/transport/chttp2/frame_data.h
+++ b/src/core/transport/chttp2/frame_data.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_DATA_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_DATA_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_DATA_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_DATA_H
 
 /* Parser for GRPC streams embedded in DATA frames */
 
@@ -77,4 +77,4 @@
 /* create a slice with an empty data frame and is_last set */
 gpr_slice grpc_chttp2_data_frame_create_empty_close(gpr_uint32 id);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_DATA_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_DATA_H */
diff --git a/src/core/transport/chttp2/frame_goaway.h b/src/core/transport/chttp2/frame_goaway.h
index 9ccef27..7638891 100644
--- a/src/core/transport/chttp2/frame_goaway.h
+++ b/src/core/transport/chttp2/frame_goaway.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_GOAWAY_H_
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_GOAWAY_H_
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_GOAWAY_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_GOAWAY_H
 
 #include "src/core/transport/chttp2/frame.h"
 #include <grpc/support/port_platform.h>
@@ -71,4 +71,4 @@
                                gpr_slice debug_data,
                                gpr_slice_buffer *slice_buffer);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_GOAWAY_H_ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_GOAWAY_H */
diff --git a/src/core/transport/chttp2/frame_ping.h b/src/core/transport/chttp2/frame_ping.h
index d9d6f7e..11d38b8 100644
--- a/src/core/transport/chttp2/frame_ping.h
+++ b/src/core/transport/chttp2/frame_ping.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_PING_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_PING_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_PING_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_PING_H
 
 #include <grpc/support/slice.h>
 #include "src/core/transport/chttp2/frame.h"
@@ -50,4 +50,4 @@
 grpc_chttp2_parse_error grpc_chttp2_ping_parser_parse(
     void *parser, grpc_chttp2_parse_state *state, gpr_slice slice, int is_last);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_PING_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_PING_H */
diff --git a/src/core/transport/chttp2/frame_rst_stream.h b/src/core/transport/chttp2/frame_rst_stream.h
index 83fc380..2d3ee18 100644
--- a/src/core/transport/chttp2/frame_rst_stream.h
+++ b/src/core/transport/chttp2/frame_rst_stream.h
@@ -31,11 +31,11 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H
 
 #include <grpc/support/slice.h>
 
 gpr_slice grpc_chttp2_rst_stream_create(gpr_uint32 stream_id, gpr_uint32 code);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_RST_STREAM_H */
diff --git a/src/core/transport/chttp2/frame_settings.h b/src/core/transport/chttp2/frame_settings.h
index 6cde2c6..1876563 100644
--- a/src/core/transport/chttp2/frame_settings.h
+++ b/src/core/transport/chttp2/frame_settings.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_SETTINGS_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_SETTINGS_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_SETTINGS_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_SETTINGS_H
 
 #include <grpc/support/port_platform.h>
 #include <grpc/support/slice.h>
@@ -96,4 +96,4 @@
 grpc_chttp2_parse_error grpc_chttp2_settings_parser_parse(
     void *parser, grpc_chttp2_parse_state *state, gpr_slice slice, int is_last);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_SETTINGS_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_SETTINGS_H */
diff --git a/src/core/transport/chttp2/frame_window_update.h b/src/core/transport/chttp2/frame_window_update.h
index 093263d..85475a8 100644
--- a/src/core/transport/chttp2/frame_window_update.h
+++ b/src/core/transport/chttp2/frame_window_update.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H
 
 #include <grpc/support/slice.h>
 #include "src/core/transport/chttp2/frame.h"
@@ -52,4 +52,4 @@
 grpc_chttp2_parse_error grpc_chttp2_window_update_parser_parse(
     void *parser, grpc_chttp2_parse_state *state, gpr_slice slice, int is_last);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_FRAME_WINDOW_UPDATE_H */
diff --git a/src/core/transport/chttp2/hpack_parser.h b/src/core/transport/chttp2/hpack_parser.h
index 94acc88..bb4c1a1 100644
--- a/src/core/transport/chttp2/hpack_parser.h
+++ b/src/core/transport/chttp2/hpack_parser.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_PARSER_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_PARSER_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_PARSER_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_PARSER_H
 
 #include <stddef.h>
 
@@ -108,4 +108,4 @@
     void *hpack_parser, grpc_chttp2_parse_state *state, gpr_slice slice,
     int is_last);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_PARSER_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_PARSER_H */
diff --git a/src/core/transport/chttp2/hpack_table.h b/src/core/transport/chttp2/hpack_table.h
index ea0fc1d..d3bf41b 100644
--- a/src/core/transport/chttp2/hpack_table.h
+++ b/src/core/transport/chttp2/hpack_table.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_TABLE_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_TABLE_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H
 
 #include "src/core/transport/metadata.h"
 #include <grpc/support/port_platform.h>
@@ -94,4 +94,4 @@
 grpc_chttp2_hptbl_find_result grpc_chttp2_hptbl_find(
     const grpc_chttp2_hptbl *tbl, grpc_mdelem *md);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_HPACK_TABLE_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H */
diff --git a/src/core/transport/chttp2/http2_errors.h b/src/core/transport/chttp2/http2_errors.h
index 1eecd17..4ab2ec0 100644
--- a/src/core/transport/chttp2/http2_errors.h
+++ b/src/core/transport/chttp2/http2_errors.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_HTTP2_ERRORS_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_HTTP2_ERRORS_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HTTP2_ERRORS_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HTTP2_ERRORS_H
 
 /* error codes for RST_STREAM from http2 draft 14 section 7 */
 typedef enum {
@@ -53,4 +53,4 @@
   GRPC_CHTTP2__ERROR_DO_NOT_USE = -1
 } grpc_chttp2_error_code;
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_HTTP2_ERRORS_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HTTP2_ERRORS_H */
diff --git a/src/core/transport/chttp2/huffsyms.h b/src/core/transport/chttp2/huffsyms.h
index 131c4ac..f9c1447 100644
--- a/src/core/transport/chttp2/huffsyms.h
+++ b/src/core/transport/chttp2/huffsyms.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_HUFFSYMS_H_
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_HUFFSYMS_H_
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HUFFSYMS_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HUFFSYMS_H
 
 /* HPACK static huffman table */
 
@@ -45,4 +45,4 @@
 
 extern const grpc_chttp2_huffsym grpc_chttp2_huffsyms[GRPC_CHTTP2_NUM_HUFFSYMS];
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_HUFFSYMS_H_ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HUFFSYMS_H */
diff --git a/src/core/transport/chttp2/status_conversion.h b/src/core/transport/chttp2/status_conversion.h
index 8e26720..cf06c35 100644
--- a/src/core/transport/chttp2/status_conversion.h
+++ b/src/core/transport/chttp2/status_conversion.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_STATUS_CONVERSION_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_STATUS_CONVERSION_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STATUS_CONVERSION_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STATUS_CONVERSION_H
 
 #include <grpc/grpc.h>
 #include "src/core/transport/chttp2/http2_errors.h"
@@ -47,4 +47,4 @@
 grpc_status_code grpc_chttp2_http2_status_to_grpc_status(int status);
 int grpc_chttp2_grpc_status_to_http2_status(grpc_status_code status);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_STATUS_CONVERSION_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STATUS_CONVERSION_H */
diff --git a/src/core/transport/chttp2/stream_encoder.h b/src/core/transport/chttp2/stream_encoder.h
index a99d61a..50c58ad 100644
--- a/src/core/transport/chttp2/stream_encoder.h
+++ b/src/core/transport/chttp2/stream_encoder.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_ENCODER_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_ENCODER_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_ENCODER_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_ENCODER_H
 
 #include "src/core/transport/chttp2/frame.h"
 #include "src/core/transport/metadata.h"
@@ -90,4 +90,4 @@
                         grpc_chttp2_hpack_compressor *compressor,
                         gpr_slice_buffer *output);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_ENCODER_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_ENCODER_H */
diff --git a/src/core/transport/chttp2/stream_map.h b/src/core/transport/chttp2/stream_map.h
index 3fb91fc..d338d2f 100644
--- a/src/core/transport/chttp2/stream_map.h
+++ b/src/core/transport/chttp2/stream_map.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_MAP_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_MAP_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_MAP_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_MAP_H
 
 #include <grpc/support/port_platform.h>
 
@@ -78,4 +78,4 @@
                                                void *value),
                                      void *user_data);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_STREAM_MAP_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_STREAM_MAP_H */
diff --git a/src/core/transport/chttp2/timeout_encoding.h b/src/core/transport/chttp2/timeout_encoding.h
index 2bef8ba..e6664c6 100644
--- a/src/core/transport/chttp2/timeout_encoding.h
+++ b/src/core/transport/chttp2/timeout_encoding.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H_
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H_
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H
 
 #include "src/core/support/string.h"
 #include <grpc/support/time.h>
@@ -44,4 +44,4 @@
 void grpc_chttp2_encode_timeout(gpr_timespec timeout, char *buffer);
 int grpc_chttp2_decode_timeout(const char *buffer, gpr_timespec *timeout);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H_ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TIMEOUT_ENCODING_H */
diff --git a/src/core/transport/chttp2/varint.h b/src/core/transport/chttp2/varint.h
index 8c353c6..ee04ed7 100644
--- a/src/core/transport/chttp2/varint.h
+++ b/src/core/transport/chttp2/varint.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_VARINT_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_VARINT_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_VARINT_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_VARINT_H
 
 #include <grpc/support/port_platform.h>
 
@@ -71,4 +71,4 @@
     }                                                                       \
   } while (0)
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_VARINT_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_VARINT_H */
diff --git a/src/core/transport/chttp2_transport.h b/src/core/transport/chttp2_transport.h
index 6fbc596..c5b65bd 100644
--- a/src/core/transport/chttp2_transport.h
+++ b/src/core/transport/chttp2_transport.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_CHTTP2_TRANSPORT_H__
-#define __GRPC_INTERNAL_TRANSPORT_CHTTP2_TRANSPORT_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TRANSPORT_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TRANSPORT_H
 
 #include "src/core/iomgr/endpoint.h"
 #include "src/core/transport/transport.h"
@@ -44,4 +44,4 @@
                                   size_t nslices, grpc_mdctx *metadata_context,
                                   int is_client);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_CHTTP2_TRANSPORT_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_TRANSPORT_H */
diff --git a/src/core/transport/metadata.h b/src/core/transport/metadata.h
index 7a56e34..b8afbeb 100644
--- a/src/core/transport/metadata.h
+++ b/src/core/transport/metadata.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_METADATA_H__
-#define __GRPC_INTERNAL_TRANSPORT_METADATA_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_METADATA_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_METADATA_H
 
 #include <grpc/support/slice.h>
 #include <grpc/support/useful.h>
@@ -137,4 +137,4 @@
 
 #define GRPC_MDSTR_KV_HASH(k_hash, v_hash) (GPR_ROTL((k_hash), 2) ^ (v_hash))
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_METADATA_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_METADATA_H */
diff --git a/src/core/transport/stream_op.h b/src/core/transport/stream_op.h
index 828a7f7..2ffbcce 100644
--- a/src/core/transport/stream_op.h
+++ b/src/core/transport/stream_op.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_STREAM_OP_H__
-#define __GRPC_INTERNAL_TRANSPORT_STREAM_OP_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_STREAM_OP_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_STREAM_OP_H
 
 #include <grpc/grpc.h>
 #include <grpc/support/port_platform.h>
@@ -131,4 +131,4 @@
 void grpc_sopb_append(grpc_stream_op_buffer *sopb, grpc_stream_op *ops,
                       size_t nops);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_STREAM_OP_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_STREAM_OP_H */
diff --git a/src/core/transport/transport.h b/src/core/transport/transport.h
index 60193b1..ce8c17c 100644
--- a/src/core/transport/transport.h
+++ b/src/core/transport/transport.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__
-#define __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H
 
 #include <stddef.h>
 
@@ -254,4 +254,4 @@
    used as a destruction call by setup). */
 void grpc_transport_setup_cancel(grpc_transport_setup *setup);
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_TRANSPORT_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_H */
diff --git a/src/core/transport/transport_impl.h b/src/core/transport/transport_impl.h
index d1e0b19..ac275c7 100644
--- a/src/core/transport/transport_impl.h
+++ b/src/core/transport/transport_impl.h
@@ -31,8 +31,8 @@
  *
  */
 
-#ifndef __GRPC_INTERNAL_TRANSPORT_TRANSPORT_IMPL_H__
-#define __GRPC_INTERNAL_TRANSPORT_TRANSPORT_IMPL_H__
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_IMPL_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_IMPL_H
 
 #include "src/core/transport/transport.h"
 
@@ -84,4 +84,4 @@
   const grpc_transport_vtable *vtable;
 };
 
-#endif /* __GRPC_INTERNAL_TRANSPORT_TRANSPORT_IMPL_H__ */
+#endif  /* GRPC_INTERNAL_CORE_TRANSPORT_TRANSPORT_IMPL_H */