1 ------------------------------------------------- 2 - README file for the LTP GCOV extension (LCOV) - 3 - Last changes: 2012-10-10 - 4 ------------------------------------------------- 5 6 Description 7 ----------- 8 LCOV is an extension of GCOV, a GNU tool which provides information about 9 what parts of a program are actually executed (i.e. "covered") while running 10 a particular test case. The extension consists of a set of Perl scripts 11 which build on the textual GCOV output to implement the following enhanced 12 functionality: 13 14 * HTML based output: coverage rates are additionally indicated using bar 15 graphs and specific colors. 16 17 * Support for large projects: overview pages allow quick browsing of 18 coverage data by providing three levels of detail: directory view, 19 file view and source code view. 20 21 LCOV was initially designed to support Linux kernel coverage measurements, 22 but works as well for coverage measurements on standard user space 23 applications. 24 25 26 Further README contents 27 ----------------------- 28 1. Included files 29 2. Installing LCOV 30 3. An example of how to access kernel coverage data 31 4. An example of how to access coverage data for a user space program 32 5. Questions and Comments 33 34 35 36 1. Important files 37 ------------------ 38 README - This README file 39 CHANGES - List of changes between releases 40 bin/lcov - Tool for capturing LCOV coverage data 41 bin/genhtml - Tool for creating HTML output from LCOV data 42 bin/gendesc - Tool for creating description files as used by genhtml 43 bin/geninfo - Internal tool (creates LCOV data files) 44 bin/genpng - Internal tool (creates png overviews of source files) 45 bin/install.sh - Internal tool (takes care of un-/installing) 46 descriptions.tests - Test descriptions for the LTP suite, use with gendesc 47 man - Directory containing man pages for included tools 48 example - Directory containing an example to demonstrate LCOV 49 lcovrc - LCOV configuration file 50 Makefile - Makefile providing 'install' and 'uninstall' targets 51 52 53 2. Installing LCOV 54 ------------------ 55 The LCOV package is available as either RPM or tarball from: 56 57 http://ltp.sourceforge.net/coverage/lcov.php 58 59 To install the tarball, unpack it to a directory and run: 60 61 make install 62 63 Use anonymous CVS for the most recent (but possibly unstable) version: 64 65 cvs -d:pserver:anonymous (a] ltp.cvs.sourceforge.net:/cvsroot/ltp login 66 67 (simply press the ENTER key when asked for a password) 68 69 cvs -z3 -d:pserver:anonymous (a] ltp.cvs.sourceforge.net:/cvsroot/ltp export -D now utils 70 71 Change to the utils/analysis/lcov directory and type: 72 73 make install 74 75 76 3. An example of how to access kernel coverage data 77 --------------------------------------------------- 78 Requirements: get and install the gcov-kernel package from 79 80 http://sourceforge.net/projects/ltp 81 82 Copy the resulting gcov kernel module file to either the system wide modules 83 directory or the same directory as the Perl scripts. As root, do the following: 84 85 a) Resetting counters 86 87 lcov --zerocounters 88 89 b) Capturing the current coverage state to a file 90 91 lcov --capture --output-file kernel.info 92 93 c) Getting HTML output 94 95 genhtml kernel.info 96 97 Point the web browser of your choice to the resulting index.html file. 98 99 100 4. An example of how to access coverage data for a user space program 101 --------------------------------------------------------------------- 102 Requirements: compile the program in question using GCC with the options 103 -fprofile-arcs and -ftest-coverage. During linking, make sure to specify 104 -lgcov or -coverage. 105 106 Assuming the compile directory is called "appdir", do the following: 107 108 a) Resetting counters 109 110 lcov --directory appdir --zerocounters 111 112 b) Capturing the current coverage state to a file (works only after the 113 application has been started and stopped at least once) 114 115 lcov --directory appdir --capture --output-file app.info 116 117 c) Getting HTML output 118 119 genhtml app.info 120 121 Point the web browser of your choice to the resulting index.html file. 122 123 Please note that independently of where the application is installed or 124 from which directory it is run, the --directory statement needs to 125 point to the directory in which the application was compiled. 126 127 For further information on the gcc profiling mechanism, please also 128 consult the gcov man page. 129 130 131 5. Questions and comments 132 ------------------------- 133 See the included man pages for more information on how to use the LCOV tools. 134 135 Please email further questions or comments regarding this tool to the 136 LTP Mailing list at ltp-coverage (a] lists.sourceforge.net 137 138
