Linux覆盖率一点研究：获取覆盖率数据

　　 首先，当然哥不介意你鄙视我在网上找的资料研究！

　　白盒覆盖率是啥东东这个问题大家自己查百度啦！我也不太懂，就知道它不是个东西，就这样开始吧（MT一般是先摸四蹄呢还是先黑金币呢？这是个问题）！

　　首先：linux先Clear一下，然后呢再ls下。然后呢再找个CPP文件。其实生成覆盖率主要就一个参数的问题。因为g++那啥已经带了获取覆盖率的功能。

     下面是执行获取覆盖率的一个流程：其中红色字体是敲入的重要命令。

[lixiang@localhost cjj]$ clear
[lixiang@localhost cjj]$ ls
ctest.c voctorTest.cpp
[lixiang@localhost cjj]$ g++ -fprofile-arcs -ftest-coverage voctorTest.cpp -o test
[lixiang@localhost cjj]$ ls
ctest.c test voctorTest.bb voctorTest.bbg voctorTest.cpp
[lixiang@localhost cjj]$ ./test
start test:

vector include num:120

end test
[lixiang@localhost cjj]$ ls
ctest.c test voctorTest.bb voctorTest.bbg voctorTest.cpp voctorTest.da
[lixiang@localhost cjj]$ gcov voctorTest.cpp
100.00% of 1 source lines executed in file /usr/include/c++/3.2.2/new
Creating new.gcov.
100.00% of 1 source lines executed in file /usr/include/c++/3.2.2/iostream
Creating iostream.gcov.
100.00% of 2 source lines executed in file /usr/include/c++/3.2.2/bits/stl_uninitialized.h
Creating stl_uninitialized.h.gcov.
42.86% of 14 source lines executed in file /usr/include/c++/3.2.2/bits/stl_algobase.h
Creating stl_algobase.h.gcov.
100.00% of 6 source lines executed in file /usr/include/c++/3.2.2/bits/stl_iterator.h
Creating stl_iterator.h.gcov.
100.00% of 4 source lines executed in file /usr/include/c++/3.2.2/bits/stl_construct.h
Creating stl_construct.h.gcov.
73.81% of 42 source lines executed in file /usr/include/c++/3.2.2/bits/stl_vector.h
Creating stl_vector.h.gcov.
100.00% of 6 source lines executed in file /usr/include/c++/3.2.2/bits/stl_alloc.h
Creating stl_alloc.h.gcov.
100.00% of 8 source lines executed in file voctorTest.cpp
Creating voctorTest.cpp.gcov.
[lixiang@localhost cjj]$ ls
ctest.c stl_construct.h.gcov voctorTest.bb
iostream.gcov stl_iterator.h.gcov voctorTest.bbg
new.gcov stl_uninitialized.h.gcov voctorTest.cpp
stl_algobase.h.gcov stl_vector.h.gcov voctorTest.cpp.gcov
stl_alloc.h.gcov test voctorTest.da

执行完后：其中覆盖率数据保存在voctorTest.cpp.gcov这个文件中。可以用cat命令查看覆盖率信息，查看的结果如下：

[lixiang@localhost cjj]$ cat voctorTest.cpp.gcov
#include "iostream"
#include<vector>
using namespace std;
int main()
1 {
3 vector<int> vec;
1 vec.push_back(120);
1 cout<<"start test:rn"<<endl;
1 cout<<"vector include num:"<<vec[0]<<"rn"<<endl;
1 cout<<"end test"<<endl;
1 return 0;
1 }
[lixiang@localhost cjj]$

其中文件每行前面的数字代表着执行的次数。如下图解释的一样一样的。该图也是拷贝其他文章的奥。

OK，这里覆盖率数据就算得到和显示出来并看到了，然后其实他们有的人还用LCov把该报告转换成html文件，由于哥今天安装了WinSCP神器软件，所以俺也准备试试，可以下载到本地来看看，有意思，好玩，好玩！LCov主要是看到第二篇文章。

坑爹了.........    哥hai 没安装LCov........    无语中：

下载一个Lcov来安装，提示依赖项没有，添加个命令来执行nodeps  其中在nodeps前面要加”--“   记住是两个”-“，不然会提示”-nodeps：unknown option“

安装时又提示：cannot get exclusive lock  on /var/lib/rpm/packages

该问题我猜是由于安装软件莫得权限，然后查资料果然正确，需要root权限，但是想到root权限安装的软件普通用户是不是基本都能用呢？所以我试下：

经过上面的折腾，觉得应该正确安装命令应该是：

rpm -ihv --nodeps lcov-1.10-1.noarch.rpm

参考文章：http://linux.sheup.com/linux/linux5218.htm

http://www.jb51.net/os/RedHat/1277.html

好辛苦，终于安装LCov成功了。安装过程中还遇到几个问题。

rpmdb:unable to join the environment

该问题主要是由于文件出了问题样，应该是系统文件，然后参考如下文章：http://blog.csdn.net/avilifans/article/details/17751545

使用export LD_ASSUME_KERNEL =2.2.25这个命令，即可解决了。

安装成功LCov后：

[lixiang@localhost lixiang]$ lcov
lcov: Need one of options -z, -c, -a, -e, -r, -l, --diff or --summary
Use lcov --help to get usage information
[lixiang@localhost lixiang]$

然后执行LCov，下面是整个命令过程，红色加粗为输入命令：

[lixiang@localhost lixiang]$ ls
file SaveSoft
[lixiang@localhost lixiang]$ lcov
lcov: Need one of options -z, -c, -a, -e, -r, -l, --diff or --summary
Use lcov --help to get usage information
[lixiang@localhost lixiang]$ [lixiang@localhost lixiang]$ lcov
-bash: [lixiang@localhost: command not found
[lixiang@localhost lixiang]$ lcov: Need one of options -z, -c, -a, -e, -r, -l, --diff or --summary
-bash: lcov:: command not found
[lixiang@localhost lixiang]$ Use lcov --help to get usage information
-bash: Use: command not found
[lixiang@localhost lixiang]$ [lixiang@localhost lixiang]$
-bash: [lixiang@localhost: command not found
[lixiang@localhost lixiang]$ ls
file SaveSoft
[lixiang@localhost lixiang]$ cd file
[lixiang@localhost file]$ ls
addpe c shellscript
[lixiang@localhost file]$ cd addpe
[lixiang@localhost addpe]$ ls
add.c add.o cjj main.c makefile prcessadmin
add.h CExample1.c ExTest main.o oldfile TestOpenFile.c
[lixiang@localhost addpe]$ cd cjj
[lixiang@localhost cjj]$ ls
ctest.c stl_construct.h.gcov voctorTest.bb
iostream.gcov stl_iterator.h.gcov voctorTest.bbg
new.gcov stl_uninitialized.h.gcov voctorTest.cpp
stl_algobase.h.gcov stl_vector.h.gcov voctorTest.cpp.gcov
stl_alloc.h.gcov test voctorTest.da
[lixiang@localhost cjj]$ lcov -c -d ./ -o app.info
Capturing coverage data from ./
Found gcov version: 3.2.2
Scanning ./ for .da files ...
Found 1 data files in ./
Processing voctorTest.da
geninfo: WARNING: cannot find an entry for iostream.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for new.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_algobase.h.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_alloc.h.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_construct.h.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_iterator.h.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_uninitialized.h.gcov in .bb file, skipping file!
geninfo: WARNING: cannot find an entry for stl_vector.h.gcov in .bb file, skipping file!
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/iostream
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_algobase.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_vector.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_alloc.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_construct.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_iterator.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/bits/stl_uninitialized.h
geninfo: WARNING: no data found for /usr/include/c++/3.2.2/new
Finished .info-file creation
[lixiang@localhost cjj]$ ls
app.info test voctorTest.bbg voctorTest.da
ctest.c voctorTest.bb voctorTest.cpp
[lixiang@localhost cjj]$ cat app.info
TN:
SF:/home/lixiang/file/addpe/cjj/voctorTest.cpp
DA:5,1
DA:6,3
DA:7,1
DA:8,1
DA:9,1
DA:10,1
DA:11,1
DA:12,1
LF:8
LH:8
end_of_record
[lixiang@localhost cjj]$ genhtml app.info -o cc_result
Reading data file app.info
Found 1 entries.
Found common filename prefix "/home/lixiang/file/addpe"
Writing .css and .png files.
Generating output.
Processing file cjj/voctorTest.cpp
Writing directory view page.
Overall coverage rate:
lines......: 100.0% (8 of 8 lines)
functions..: no data found
[lixiang@localhost cjj]$

其中:

lcov：我想查看下LCov是否安装成功。（证明了在root下安装的软件可以在普通用户下使用。但是注意，我安装的时候用普通用户的保存的安装包好像有点问题。）

lcov -c -d ./ -o app.info：这条命令是创建覆盖率中间文件app.info 该文件可以用cat、vi查看。前提该文件夹下有gcov后缀的文件存在，即该文件是生成覆盖率信息的文件夹下。

genhtml app.info -o cc_result：通过lcov自带的genhtml转换为html文件并放在cc_result文件夹下。

获取到的覆盖率结果如下：

总结获取覆盖率步骤：

      1. 编译链接带覆盖率参数的源代码;

　　2. 运行测试程序;

　　3. 使用gcov获取文本形式的覆盖率数据;

　　4. 使用lcov获取html形式的覆盖率数据;

参考了这篇文章：

http://blog.163.com/bobile45@126/blog/static/96061992201382025729313/

http://linux.ctocio.com.cn/85/12444085.shtml