Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich S&MA Directorate

Can CodeSurfer Increase Code Inspection Efficiency?

A Research Infusion Project

Mark Markovich - SAIC

Dan Freund – NASA Principal Investigator

Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich Safety and Mission Assurance Directorate

About CodeSurfer RI

• About Us– JSC Safety and Mission Assurance Directorate, Flight Equipment Division - We assure

software for Government Furnished Equipment (GFE). These are flight projects, usually small to moderately sized, typically ranging between 1,000 and 50,000 lines of code. :

• What is CodeSurfer?– CodeSurfer is a static analysis tool from Grammatech, Inc. used for source code analysis

and navigation. CodeSurfer does not itself find defects in the code. Its purpose is to make the trained reviewer more effective. CodeSurfer includes many capabilities that could decrease the amount of time required to review the code by enabling the reviewer to perform them more quickly. In addition, CodeSurfer also has capabilities that could allow the reviewer additional technical insight into the workings of the code.

• What is Static Analysis?– Static analysis examines non-executing code and analyzes all known, possible behaviors

that might arise at run time. The analysis of code during execution is known as dynamic analysis.

• Projects– Space Integrated Global Positioning System / Inertial Navigation System (SIGI)– Health Management System Defibrillator (Defib) Power and Data Interface Module (PDIM)

• Approach– Perform a code inspection without CodeSurfer, collecting appropriate metrics on time

required and defects identified. Using a different software engineer, inspect the software using CodeSurfer, collecting the same metrics. Both inspectors used the same checklist.

Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich Safety and Mission Assurance Directorate

CodeSurfer Features

• Features Pointer analysis, including which pointers point to which variables and

procedures Shows call graphs that are complete, even when indirect function calls are used Shows all the variables a function uses and all the variables a function can

modify Show all statements that depend on a selected statement, including code in

other files Can search the entire application for user specified items Shows why statements execute, and can be used to follow the control code one

step at a time using the provided hyperlinks Allows users to right-click on a macro and navigate to the macro’s definition. Follows preprocessor directives during build. Conditionally-compiled code (not

part of the current build) is color coded

Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich Safety and Mission Assurance Directorate

Most Useful Capabilities

• Puts code in visually appealing format allows user to quickly scan the code for problems

• Checking variable initialization is very easy

• Queries

• Easy identification of dead code and unused variables

Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich Safety and Mission Assurance Directorate

Results

COMBINED SIGI AND PDIM INSPECTION DATA

Metric Manual Code inspection With CodeSurfer

Inspection Time (hr) 17 12.25

Lines of Code (LOC) 10650 10650

Inspection Rate (LOC/hr) 626 869

Total Defects Found Using Method 8 18

Defects Found per Hour 0.47 1.47

Unique Defects Found Using Method 2 12

Johnson Space Center

SAS05_CodeSurfer_Infusion_JSC_Markovich Safety and Mission Assurance Directorate

Challenges and Recommendations

• CodeSurfer can only be used to analyze code that can be compiled using one of several common compilers provided with the tool. Code analysis can be difficult where developer used a different compiler. This can be a problem when supporting multiple development labs

• Export restrictions made it difficult to seek technical assistance.

• Training and onsite visits by the vendor is expensive. But trying to figure it out on your own may be even more expensive. Research Infusion proposals should strongly consider including training and onsite support by the vendor

• Identifying the correct files for compilation can be difficult

• Regular use is required to maintain competence

It is fair to note that other tools are likely to have similar problems if they require a compile or build of the software to be analyzed.