Merge branch 'rs/swap'

Code clean-up.

* rs/swap:
  graph: use SWAP macro
  diff: use SWAP macro
  use SWAP macro
  apply: use SWAP macro
  add SWAP macro

git-compat-util.h

@@ -527,6 +527,16 @@ static inline int ends_with(const char *str, const char *suffix)
 	return strip_suffix(str, suffix, &len);
 }
 
+#define SWAP(a, b) do {						\
+	void *_swap_a_ptr = &(a);				\
+	void *_swap_b_ptr = &(b);				\
+	unsigned char _swap_buffer[sizeof(a)];			\
+	memcpy(_swap_buffer, _swap_a_ptr, sizeof(a));		\
+	memcpy(_swap_a_ptr, _swap_b_ptr, sizeof(a) +		\
+	       BUILD_ASSERT_OR_ZERO(sizeof(a) == sizeof(b)));	\
+	memcpy(_swap_b_ptr, _swap_buffer, sizeof(a));		\
+} while (0)
+
 #if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
 
 #ifndef PROT_READ