NAME

goto-harness - Generate environments for symbolic analysis

SYNOPSIS

goto-harness [-?] [-h] [--help]: show help
goto-harness --version: show version
goto-harness in out --harness-function-name name --harness-type harness-type [harness-options]: build harness for in and write harness to out; the harness is printed as C code, if out has a .c suffix, else a GOTO binary including the harness is generated

DESCRIPTION

goto-harness constructs functions that set up an appropriate environment before calling functions under analysis. This is most useful when trying to analyze an isolated unit of a program.

A typical sequence of tool invocations is as follows. Given a C program program.c, we generate a harness for function test_function:

# Compile the program
goto-cc program.c -o program.gb
# Run goto-harness to produce harness file
goto-harness --harness-type call-function --harness-function-name generated_harness_test_function


  --function test_function program.gb harness.c
# Run the checks targeting the generated harness
cbmc --pointer-check harness.c --function generated_harness_test_function

goto-harness has two main modes of operation. First,function-call harnesses, which automatically synthesize an environment without having any information about the program state. Second, memory-snapshot harnesses, in which case goto-harness loads an existing program state as generated by memory-analyzer(1) and selectively havocs some variables.

OPTIONS

--harness-function-name name: Use name as the name of the harness function that is generated, i.e., the new entry point.
--harness-type [call-function|initialize-with-memory-snapshot]: Select the type of harness to generate. In addition to options applicable to both harness generators, each of them also has dedicated options that are described below.

Common generator options

--min-null-tree-depth N: Set the minimum level at which a pointer can first be NULL in a recursively non-deterministically initialized struct to N. Defaults to 1.
--max-nondet-tree-depth N: Set the maximum height of the non-deterministic object tree to N. At that level, all pointers will be set to NULL. Defaults to 2.
--min-array-size N: Set the minimum size of arrays of non-constant size allocated by the harness to N. Defaults to 1.
--max-array-size N: Set the maximum size of arrays of non-constant size allocated by the harness to N. Defaults to 2.
--nondet-globals: Set global variables to non-deterministic values in harness.
--havoc-member member-expr: Non-deterministically initialize member-expr of some global object (may be given multiple times).
--function-pointer-can-be-null function-name: Name of parameters of the target function or of global variables of function-pointer type that can non-deterministically be set to NULL.

Function harness generator (--harness-type call-function):

--function function-name: Generate an environment to call function function-name, which the harness will then call.
--treat-pointer-as-array p: Treat the (pointer-typed) function parameter with name p as an array.
--associated-array-size array_name:size_name: Set the function parameter size_name to the size of the array parameter array_name (implies --treat-pointer-as-array array_name).
--treat-pointers-equal p,q,r[;s,t]: Assume the pointer-typed function parameters q and r are equal to parameter p, and s equal to t, and so on.
--treat-pointers-equal-maybe: Function parameter equality is non-deterministic.
--treat-pointer-as-cstring p: Treat the function parameter with the name p as a string of characters.

Memory snapshot harness generator (--harness-type initialise-from-memory-snapshot):

--memory-snapshot file: Initialize memory from JSON memory snapshot stored in file.
--initial-goto-location func[:n]: Use function func and GOTO binary location number n as entry point.
--initial-source-location file:n: Use given file name file and line number n in that file as entry point.
--havoc-variables vars: Non-deterministically initialize all symbols named vars.
--pointer-as-array p: Treat the global pointer with name p as an array.
--size-of-array array_name:size_name: Set the variable size_name to the size of the array variable array_name (implies --pointer-as-array array_name).

ENVIRONMENT

All tools honor the TMPDIR environment variable when generating temporary files and directories.

BUGS

If you encounter a problem please create an issue at https://github.com/diffblue/cbmc/issues

COPYRIGHT

2019, Diffblue