1 files changed, 56 insertions, 0 deletions
diff --git a/src/lib/fs/freespace.c b/src/lib/fs/freespace.c
new file mode 100644
index 0000000000..926b17dbde
--- /dev/null
+++ b/src/lib/fs/freespace.c
@@ -0,0 +1,56 @@
+/* Copyright (c) 2003-2004, Roger Dingledine
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#include "lib/fs/files.h"
+#include "lib/cc/torint.h"
+
+#ifdef HAVE_SYS_STATVFS_H
+#include <sys/statvfs.h>
+#endif
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+#include <string.h>
+
+/** Return the amount of free disk space we have permission to use, in
+ * bytes. Return -1 if the amount of free space can't be determined. */
+int64_t
+tor_get_avail_disk_space(const char *path)
+{
+#ifdef HAVE_STATVFS
+  struct statvfs st;
+  int r;
+  memset(&st, 0, sizeof(st));
+
+  r = statvfs(path, &st);
+  if (r < 0)
+    return -1;
+
+  int64_t result = st.f_bavail;
+  if (st.f_frsize) {
+    result *= st.f_frsize;
+  } else if (st.f_bsize) {
+    result *= st.f_bsize;
+  } else {
+    return -1;
+  }
+
+  return result;
+#elif defined(_WIN32)
+  ULARGE_INTEGER freeBytesAvail;
+  BOOL ok;
+
+  ok = GetDiskFreeSpaceEx(path, &freeBytesAvail, NULL, NULL);
+  if (!ok) {
+    return -1;
+  }
+  return (int64_t)freeBytesAvail.QuadPart;
+#else
+  (void)path;
+  errno = ENOSYS;
+  return -1;
+#endif /* defined(HAVE_STATVFS) || ... */
+}