Add some helper macros and wrappers for C library functions.

- touch()    - Create a file, or update mtime.  Errors on stderr
- makedir()  - Create directory, like mkdir().  Errors on stderr
- makefifo() - Create a FIFO, like mkfifo().  Errors on stderr
- erase()    - Erase file/directory with remove().  Errors on stderr
- chardev()  - Create character device
- blkdev()   - Create block device
- S_ISEXEC() - Mysteriously missing from GLIBC
- UNUSED()   - Shorter and more readable version of __attribute__ ((unused))

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

lite.h

@@ -25,6 +25,7 @@
 #ifndef FINIT_LITE_H_
 #define FINIT_LITE_H_
 
+#include <error.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
@@ -54,6 +55,32 @@ size_t  strlcat    (char *dst, const char *src, size_t siz);
 long long strtonum (const char *numstr, long long minval, long long maxval, const char **errstrp);
 #endif
 
+#ifndef touch
+# define touch(x) do { if (mknod((x), S_IFREG|0644, 0) && errno != EEXIST) error(0, errno, "Failed creating %s", x); } while (0)
+#endif
+#ifndef makedir
+# define makedir(x, p) do { if (mkdir(x, p) && errno != EEXIST) error(0, errno, "Failed creating directory %s", x); } while (0)
+#endif
+#ifndef makefifo
+# define makefifo(x, p) do { if (mkfifo(x, p) && errno != EEXIST) error(0, errno, "Failed creating FIFO %s", x); } while (0)
+#endif
+#ifndef erase
+# define erase(x) do { if (remove(x) && errno != ENOENT) error(0, errno, "Failed removing %s", x); } while (0)
+#endif
+#ifndef chardev
+# define chardev(x,m,maj,min) mknod((x), S_IFCHR|(m), makedev((maj),(min)))
+#endif
+#ifndef blkdev
+# define blkdev(x,m,maj,min) mknod((x), S_IFBLK|(m), makedev((maj),(min)))
+#endif
+#ifndef S_ISEXEC
+# define S_ISEXEC(m) (((m) & S_IXUSR) == S_IXUSR)
+#endif
+#ifndef UNUSED
+#define UNUSED(x) UNUSED_ ## x __attribute__ ((unused))
+#endif
+
+
 static inline int fisslashdir(char *dir)
 {
    if (!dir)             return 0;