Add support for fmkpath(), formatted string mkpath()

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

src/lite.h

@@ -81,6 +81,7 @@ char   *lfgetkey   (lfile_t *lf, const char *key);
 int     lfgetint   (lfile_t *lf, const char *key);
 int     fgetint    (const char *file, const char *sep, const char *key);
 
+int     fmkpath    (mode_t mode, const char *fmt, ...);
 int     mkpath     (const char *dir, mode_t mode);
 int     makepath   (const char *dir);
 

src/makepath.c

@@ -17,6 +17,8 @@
 
 #include <errno.h>
 #include <libgen.h>
+#include <stdarg.h>
+#include <stdlib.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include "lite.h"
@@ -46,6 +48,38 @@ int mkpath(const char *dir, mode_t mode)
 	return mkdir(dir, mode);
 }
 
+/**
+ * fmkpath - Formatted version of mkpath()
+ * @mode: A &mode_t mode to create directories with
+ * @fmt:  Formatted string to be composed into a pathname
+ *
+ * Note:
+ * Notice the swapped arguments, compared to mkpath()!
+ *
+ * Returns:
+ * POSIX OK(0) on success, otherwise -1 with @errno set.
+ */
+int fmkpath(mode_t mode, const char *fmt, ...)
+{
+	va_list ap;
+	char *path;
+	int len;
+
+	va_start(ap, fmt);
+	len = vsnprintf(NULL, 0, fmt, ap);
+	va_end(ap);
+
+	path = alloca(len + 1);
+	if (!path)
+		return -1;
+
+	va_start(ap, fmt);
+	len = vsnprintf(path, len + 1, fmt, ap);
+	va_end(ap);
+
+	return mkpath(path, mode);
+}
+
 /**
  * makepath - Create all components of the specified directory.
  * @dir: Directory to create.