Move generic util functions to shared directory
diff --git a/shared/util.h b/shared/util.h
new file mode 100644
index 0000000..1ed7214
--- /dev/null
+++ b/shared/util.h
@@ -0,0 +1,64 @@
+#pragma once
+
+#include <limits.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <shared/macro.h>
+
+/* string handling functions and memory allocations                         */
+/* ************************************************************************ */
+#define streq(a, b) (strcmp((a), (b)) == 0)
+#define strstartswith(a, b) (strncmp(a, b, strlen(b)) == 0)
+char *strchr_replace(char *s, int c, char r);
+void *memdup(const void *p, size_t n) __attribute__((nonnull(1)));
+
+/* read-like and fread-like functions                                       */
+/* ************************************************************************ */
+ssize_t read_str_safe(int fd, char *buf, size_t buflen) _must_check_ __attribute__((nonnull(2)));
+ssize_t write_str_safe(int fd, const char *buf, size_t buflen) __attribute__((nonnull(2)));
+int read_str_long(int fd, long *value, int base) _must_check_ __attribute__((nonnull(2)));
+int read_str_ulong(int fd, unsigned long *value, int base) _must_check_ __attribute__((nonnull(2)));
+char *getline_wrapped(FILE *fp, unsigned int *linenum) __attribute__((nonnull(1)));
+
+/* path handling functions                                                  */
+/* ************************************************************************ */
+bool path_is_absolute(const char *p) _must_check_ __attribute__((nonnull(1)));
+char *path_make_absolute_cwd(const char *p) _must_check_ __attribute__((nonnull(1)));
+int mkdir_p(const char *path, int len, mode_t mode);
+int mkdir_parents(const char *path, mode_t mode);
+unsigned long long stat_mstamp(const struct stat *st);
+unsigned long long ts_usec(const struct timespec *ts);
+
+/* endianess and alignments                                                 */
+/* ************************************************************************ */
+#define get_unaligned(ptr)			\
+({						\
+	struct __attribute__((packed)) {	\
+		typeof(*(ptr)) __v;		\
+	} *__p = (typeof(__p)) (ptr);		\
+	__p->__v;				\
+})
+
+#define put_unaligned(val, ptr)			\
+do {						\
+	struct __attribute__((packed)) {	\
+		typeof(*(ptr)) __v;		\
+	} *__p = (typeof(__p)) (ptr);		\
+	__p->__v = (val);			\
+} while(0)
+
+static _always_inline_ unsigned int ALIGN_POWER2(unsigned int u)
+{
+	return 1 << ((sizeof(u) * 8) - __builtin_clz(u - 1));
+}
+
+/* misc                                                                     */
+/* ************************************************************************ */
+static inline void freep(void *p) {
+        free(*(void**) p);
+}
+#define _cleanup_free_ _cleanup_(freep)