Usage:
uncrustify [options] [files ...]

If no input files are specified, the input is read from stdin
If reading from stdin, you should specify the language using -l
or specify a filename using --assume for automatic language detection.

If -F is used or files are specified on the command line,
the output filename is 'prefix/filename' + suffix

When reading from stdin or doing a single file via the '-f' option,
the output is dumped to stdout, unless redirected with -o FILE.

Errors are always dumped to stderr

The '-f' and '-o' options may not be used with '-F' or '--replace'.
The '--prefix' and '--suffix' options may not be used with '--replace'.

Basic Options:
 -c CFG       : Use the config file CFG, or defaults if CFG is set to '-'.
 -f FILE      : Process the single file FILE (output to stdout, use with -o).
 -o FILE      : Redirect stdout to FILE.
 -F FILE      : Read files to process from FILE, one filename per line (- is stdin).
 --check      : Do not output the new text, instead verify that nothing changes when
                the file(s) are processed.
                The status of every file is printed to stderr.
                The exit code is EXIT_SUCCESS if there were no changes, EXIT_FAILURE otherwise.
 files        : Files to process (can be combined with -F).
 --suffix SFX : Append SFX to the output filename. The default is '.uncrustify'
 --prefix PFX : Prepend PFX to the output filename path.
 --replace    : Replace source files (creates a backup).
 --no-backup  : Do not create backup and md5 files. Useful if files are under source control.
 --if-changed : Write to stdout (or create output FILE) only if a change was detected.
 -l           : Language override: C, CPP, D, CS, JAVA, PAWN, OC, OC+, VALA.
 -t           : Load a file with types (usually not needed).
 -q           : Quiet mode - no output on stderr (-L will override).
 --frag       : Code fragment, assume the first line is indented correctly.
 --assume FN  : Uses the filename FN for automatic language detection if reading
                from stdin unless -l is specified.

Config/Help Options:
 -h -? --help --usage     : Print this message and exit.
 --version                : Print the version and exit.
 --count-options          : Print the number of available options and exit.
 --show-config            : Print out option documentation and exit.
 --update-config          : Output a new config file. Use with -o FILE.
 --update-config-with-doc : Output a new config file. Use with -o FILE.
 --universalindent        : Output a config file for Universal Indent GUI.
 --detect                 : Detects the config from a source file. Use with '-f FILE'.
                            Detection is fairly limited.
 --set <option>=<value>   : Sets a new value to a config option.

Debug Options:
 -p FILE               : Dump debug info into FILE, or to stdout if FILE is set to '-'.
                         Must be used in combination with '-f FILE'
 -ds FILE              : Dump parsing info at various moments of the formatting process.
 --dump-steps FILE       This creates a series of files named 'FILE_nnn.log', each
                         corresponding to a formatting step in uncrustify.
                         The file 'FILE_000.log' lists the formatting options in use.
                         Must be used in combination with '-f FILE'
 -L SEV                : Set the log severity (see log_levels.h; note 'A' = 'all')
 -s                    : Show the log severity in the logs.
 --decode              : Decode remaining args (chunk flags) and exit.
 --tracking_space FILE : Prepare space tracking information for debugging.
 --tracking_nl FILE    : Prepare newline tracking information for debugging.
                         Cannot be used with the -o option'

Usage Examples
cat foo.d | uncrustify -q -c my.cfg -l d
uncrustify -c my.cfg -f foo.d
uncrustify -c my.cfg -f foo.d -L0-2,20-23,51
uncrustify -c my.cfg -f foo.d -o foo.d
uncrustify -c my.cfg -f foo.d -o foo.d -ds dump
uncrustify -c my.cfg foo.d
uncrustify -c my.cfg --replace foo.d
uncrustify -c my.cfg --no-backup foo.d
uncrustify -c my.cfg --prefix=out -F files.txt

Note: Use comments containing ' *INDENT-OFF*' and ' *INDENT-ON*' to disable
      processing of parts of the source file (these can be overridden with
      enable_processing_cmt and disable_processing_cmt).

There are currently x options and minimal documentation.
Try UniversalIndentGUI and good luck.