singledelta(1) heuristic minimizer of interesting files

SYNOPSIS

singledelta -test=test-script [options] [initial-file]

DESCRIPTION

Delta assists you in minimizing ``interesting'' files subject to a test of their interestingness. A common such situation is when attempting to isolate a small failure-inducing substring of a large input that causes your program to exhibit a bug.

You supply singledelta with

  • a test shell script which decides if its input file is ``interesting'' (test-script) and
  • an initial interesting input file (initial-file or standard input).

Delta uses heuristics to find a sub-file of your input file that is still ``interesting'' according to your test.

Delta has a notion of the granularity of the file: the smallest atomic elements of which the file is seen as a sequence. The default is the line granularity: in this mode, delta will attempt to delete entire lines, but will never try deleting a smaller element than that. You can filter a program through topformflat(1) to produce a file where the line-granularity only goes to a specified nesting depth (if your file is in a nested language). multidelta(1) does this for you.

OPTIONS

-test=test-script
Use test-script as the test program. This option is mandatory.

The test program accepts a single argument, the name of the candidate file to test. It is run within a directory containing only that file, and it can make temporary files/directories in that directory. It should return zero for a candidate that exhibits the desired property, and nonzero for one that does not.

-suffix=suffix
Set filename suffix to suffix. The default is ".c".
-dump_input
Dump the contents of the initial file after reading it.
-cp_minimal=file
Copy the minimal successful test to file.
-granularity=line
Use lines as the granularity. This is the default.
-granularity=top_form
Use C top-level forms as the granularity. This currently only works with CIL output.
-log=file
Log main events to file.
-quiet
Do not produce any output.
-verbose
Produce more verbose output.
-in_place
Overwrite initial-file with inputs.
-help
Print out usage information.

NOTES

The name singledelta is Debian-specific. The upstream name of this program is simply delta.