public void TestStatFs(string path, bool pathExists)
{
var pathExistsAsFile = FileUtilities.FileExistsNoFollow(path);
var pathExistsAsDir = FileUtilities.DirectoryExistsNoFollow(path);
XAssert.AreEqual(
pathExists, pathExistsAsFile || pathExistsAsDir,
$"Expected exists: {pathExists}, Actual exists as file: {pathExistsAsFile}, Actual exists as dir: {pathExistsAsDir}");
var buf = new StatFsBuffer();
int error = IO.StatFs(path, ref buf);
ulong?maybeFreeSpaceBytes = IO.FreeSpaceLeftOnDeviceInBytes(path);
if (pathExists)
{
XAssert.IsNotNull(maybeFreeSpaceBytes);
ulong freeSpaceBytes = maybeFreeSpaceBytes.Value;
var dbg = $"{path} (free {freeSpaceBytes >> 30}GB) :: {buf.f_fstypename}: {buf.f_mntfromname} -> {buf.f_mntonname}";
XAssert.AreEqual(0, error, $"Expected statfs to return 0 on {path} which exists. {dbg}");
XAssert.IsTrue(freeSpaceBytes > 0, $"Expected free space to be greater than 0B, instead it is {freeSpaceBytes}B. {dbg}");
if (path == "/")
{
XAssert.AreEqual("/", buf.f_mntonname, $"Path '/' must be mounted to '/'. {dbg}");
}
}
else
{
XAssert.AreEqual(-1, error, $"Expected statfs to return -1 on '{path}' which does not exist.");
XAssert.IsNull(maybeFreeSpaceBytes, $"Expected free space to be -1 for path '{path}' that does not exist.");
}
}
internal static string GetMountNameForPath(string path)
{
var statFsBuffer = new StatFsBuffer();
var error = StatFs(path, ref statFsBuffer);
if (error != 0)
{
return(null);
}
return(statFsBuffer.f_mntonname);
}
/// <summary>
/// Returns the number of available bytes left on a mounted file system.
/// </summary>
/// <param name="path">Path name of any file or directory within the mounted file system</param>
/// <returns>Number of available bytes or <c>null</c> on error</returns>
public static ulong?FreeSpaceLeftOnDeviceInBytes(string path)
{
var statFsBuffer = new StatFsBuffer();
var error = StatFs(path, ref statFsBuffer);
if (error != 0)
{
return(null);
}
return(statFsBuffer.f_bsize * statFsBuffer.f_bavail);
}
private static extern int StatFs([MarshalAs(UnmanagedType.LPStr)] string path, ref StatFsBuffer buf);
