C + + code coverage tool Gcov, Lcov

Gcov is a code coverage tool that can be used in C/s + +, and is a built-in tool for GCC. Here's how to use Gcov to collect code coverage information.

To collect code overwrite information with Gcov, you need to add these 2 options "-fprofile-arcs-ftest-coverage" when GCC compiles the code, and compile this simple program

Gcc-fprofile-arcs-ftest-coverage Hello.c-o Hello

After compiling, you get an executable hello and hello.gcno file, and when you compile the file with GCC, the. gcno file is generated with the "-ftest-coverage" parameter, which contains information such as the program block and line number.
Next, you can run this Hello program

./hello 5
./hello 12

A HELLO.GCDA file is generated after the run finishes and is generated if an executable file is compiled with the "-fprofile-arcs" parameter and runs at least once. This file contains information about the basic block jumps of the program. Next you can generate code coverage information with Gcov:

Gcov hello.c

2 files Hello.c.gcov and Myfunc.c.gcov are generated after the run finishes. Open the message to look inside:

-: 0:SOURCE:MYFUNC.C
-: 0:graph:hello.gcno
-: 0:DATA:HELLO.GCDA
-: 0:runs:1
-: 0:programs:1
-: 1: #include
-: 2:
-: 3:void Test (int count)
1:4:{
-: 5:int i;
10:6: for (i = 1; i < count; i++)
-: 7: {
9:8: if (i% 3 = = 0)
3:9: printf ("%d is divisible by 3 \ n", i);
9:10:if (i% 11 = = 0)
#####: 11:printf ("%d is divisible by one \ n", i);
9:12:if (i% 13 = = 0)
#####: 13:printf ("%d is divisible by", I);
-: 14:}
1:15:}

is marked as # # # #的代码行就是没有被执行过的, the code covers the correct information, but it is really a cup of tea to read these words. Don't worry, there is another tool called Lcov, you can use the program to parse these obscure characters, the final output to the HTML format of the report, very good!

Lcov-d. -T ' Hello Test '-o ' hello_test.info '-B. -C

Specify Lcov in the current directory "." To find the code to cover the information, output as ' hello_test.info ', this hello_test.info is an intermediate result, need to use it genhtml to deal with, genhtml is a tool inside the Lcov.

Genhtml-o result Hello_test.info

Specifies that the output directory is result. A full HTML report is generated, a connection is made, and the directory is attached to a directory of any Web server, so you can see the report.

My project is using Lcov, and using Makefile, the main usage is as follows:

To define a macro file in makefile:

Profile

1. Ifeq ($ (profile), 1)
2. CFLAGS + =-fprofile-arcs
3. CFLAGS + =-ftest-coverage
4. Cxxflags + =-fprofile-arcs
5. Cxxflags + =-ftest-coverage
6. Ldflags + =-fprofile-arcs
7. Ldflags + =-ftest-coverage
8. Ldflags + =-lgcov
9. Libldflags + =-fprofile-arcs
10. Libldflags + =-ftest-coverage
11. Libldflags + =-lgcov
12. endif

Open this macro at compile time: profile=1 make RTM debug=0

Then the *.GCDA file is generated after running.

Use the following command to generate the report:

2. Lcov-d. -B. -c-o $rtmcovfile >/dev/null
4. #sed-i-e ' s#/home/mac_ci/hudson/home/jobs/trunk_rtm/workspace/trunk#\. #g ' $rtmcovfile
6. #-Keep Sstddps folders in the
8. Lcov-r $rtmcovfile "*/ss_macdata/*"-O $rtmcovfile
10. Lcov-r $rtmcovfile "*/ss_macpswmp/*"-O $rtmcovfile
12. Lcov-r $rtmcovfile "*/sscommon/*"-O $rtmcovfile
14. Lcov-r $rtmcovfile "*/ssdata/*"-O $rtmcovfile
16. Lcov-r $rtmcovfile "*/ssdcmps/*"-O $rtmcovfile
18. Lcov-r $rtmcovfile "*/sspscommon/*"-O $rtmcovfile
20. Lcov-r $rtmcovfile "*/sstestmodel/*"-O $rtmcovfile
22. #-Remove unneeded paths from coverage
24. Lcov-r $rtmcovfile "/build/ltesdkroot/*"-O $rtmcovfile
26. Lcov-r $rtmcovfile "*/sc_dsp_common/*"-O $rtmcovfile
28. Lcov-r $rtmcovfile "*/c_test/*"-O $rtmcovfile
30. Lcov-r $rtmcovfile "*/t_tools/*"-O $rtmcovfile
32. Lcov-r $rtmcovfile "*/env/*"-O $rtmcovfile
34. Lcov-r $rtmcovfile "*/i_interface/*"-O $rtmcovfile
36. Lcov-r $rtmcovfile "/usr/*"-O $rtmcovfile
38. Lcov-r $rtmcovfile "/opt/*"-O $rtmcovfile
42. MV $rtmcovfile $PROJECT _root/c_test/sc_mac/maclinuxrtm/logs
44. CD $PROJECT _root/c_test/sc_mac/maclinuxrtm/logs
46. Genhtml-o tdd_ut_rtm_tests_coverage $rtmcovfile >/dev/null

Test Results Overview

Coverage for a specific file

C + + code coverage tool Gcov, Lcov