Initial commit

This initial commit has enough to make a new file system and print out
it's structures.

Signed-off-by: Zach Brown <zab@versity.com>

utils/src/util.h

@@ -0,0 +1,73 @@
+#ifndef _UTIL_H_
+#define _UTIL_H_
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * Generate build warnings if the condition is false but generate no
+ * code at run time if it's true.
+ */
+#define build_assert(cond) ((void)sizeof(char[1 - 2*!(cond)]))
+
+#define min(a, b) 		\
+({				\
+	__typeof__(a) _a = (a);	\
+	__typeof__(b) _b = (b);	\
+				\
+	_a < _b ? _a : _b;	\
+})
+
+#define max(a, b) 		\
+({				\
+	__typeof__(a) _a = (a);	\
+	__typeof__(b) _b = (b);	\
+				\
+	_a > _b ? _a : _b;	\
+})
+
+#define swap(a, b) 		\
+do {				\
+	__typeof__(a) _t = (a);	\
+ 	(a) = (b);		\
+ 	(b) = (_t);		\
+} while (0)
+
+#define array_size(arr) (sizeof(arr) / sizeof(arr[0]))
+
+#define __packed __attribute__((packed))
+
+/*
+ * Round the 'a' value up to the next 'b' power of two boundary.  It
+ * casts the mask to the value type before masking to avoid truncation
+ * problems.
+ */
+#define round_up(a, b)			\
+({					\
+	__typeof__(a) _b = (b);		\
+					\
+	((a) + _b - 1) & ~(_b - 1);	\
+})
+
+#ifndef offsetof
+#define offsetof(type, memb) ((unsigned long)&((type *)0)->memb)
+#endif
+
+#define container_of(ptr, type, memb) \
+	((type *)((void *)(ptr) - offsetof(type, memb)))
+
+/*
+ * return -1,0,+1 based on the memcmp comparison of the minimum of their
+ * two lengths.  If their min shared bytes are equal but the lengths
+ * are not then the larger length is considered greater.
+ */
+static inline int memcmp_lens(const void *a, int a_len,
+			      const void *b, int b_len)
+{
+	unsigned int len = min(a_len, b_len);
+
+	return memcmp(a, b, len) ?: a_len - b_len;
+}
+
+#endif