style: add clang-format style rules

.clang-format

@@ -0,0 +1,22 @@
+---
+Language:      Cpp
+BasedOnStyle:  Google
+
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakTemplateDeclarations: true
+BinPackArguments: false
+BinPackParameters: false
+BreakBeforeBraces: Attach
+ColumnLimit: 79
+Cpp11BracedListStyle: true
+DerivePointerAlignment: false
+IndentWrappedFunctionNames: true
+MaxEmptyLinesToKeep: 1
+PointerAlignment: Left
+SpaceAfterCStyleCast: true
+SpacesInContainerLiterals: false
+
+# Alas, not supported:
+# ForceEmptyLineAtEOF: true

src/msafd.h

@@ -9,6 +9,8 @@
 # define SIO_BASE_HANDLE 0x48000022
 #endif
 
+/* clang-format off */
+
 #define AFD_NO_FAST_IO   0x00000001
 #define AFD_OVERLAPPED   0x00000002
 #define AFD_IMMEDIATE    0x00000004
@@ -39,6 +41,8 @@
 #define AFD_NUM_POLL_EVENTS             11
 #define AFD_POLL_ALL                    ((1 << AFD_NUM_POLL_EVENTS) - 1)
 
+/* clang-format on */
+
 #define FSCTL_AFD_BASE FILE_DEVICE_NETWORK
 
 #define _AFD_CONTROL_CODE(operation, method) \

src/tree.h

@@ -53,6 +53,8 @@
 #ifndef  EPOLL_TREE_H_
 #define  EPOLL_TREE_H_
 
+/* clang-format off */
+
 #define SPLAY_HEAD(name, type)                                                \
 struct name {                                                                 \
   struct type *sph_root; /* root of the tree */                               \
@@ -757,4 +759,6 @@ name##_RB_MINMAX(struct name *head, int val)                                  \
       ((x) != NULL) && ((y) = name##_RB_PREV(x), (x) != NULL);                \
        (x) = (y))
 
+/* clang-format on */
+
 #endif  /* EPOLL_TREE_H_ */