Linting Without a Plugin

With “Eclipse and PC-lint: Linticator” I have a plugin to lint my sources in a comfortable way. But I can do this as well without a plugin. For this I use a batch file with a build configuration, plus settings to get the PC-lint messages into the Problems view. Yes, this does not sound easy, but is very doable and straight forward once I have set it up. It gives me complete control on every little detail. Here is how I do it… PC-lint is like any other compiler: it compiles my source files. But, it is not producing object code: it is producing messages. So I need to set up the compiler to compile my sources, and to produce the messages so I can click and jump to the offending source files and lines. To run PC-lint with a project in eclipse means solving three problems:

1. How to set up PC-lint as compiler for my project?
2. How to pass options to the PC-lint compiler?
3. How to configure the messages for the Problems view?

I’m using a joint approach with eclipse build configuration, batch file and lint option files. The solution presented here is using the following steps:

1. Using a managed make build configuration
2. Setting up a batch file to call PC-lint
3. Defining the list of files
4. Specifying the options
5. Defining the message format
6. Lint it!

Step 1: Build Configuration

To my existing project I add a managed make build configuration for PC-lint. The build configuration is set up to call a batch file. I select the project and use the menu Project > Build Configuration > Manage… and create a new configuration using the New button:

Creating new build configuration

For the new configuration, I copy the settings from the existing configuration:

Creating new configuration

This new configuration would just use my normal compiler. Instead, I want to use the lint compiler. In Project > Properties > C/C++ Build > Builder Settings, I disable ‘Use default build command‘ and use instead:

${ProjDirPath}\lint\do_lint.bat "${ProjDirPath}" "${MCUToolsBaseDir}"

I’m pointing to a do_lint.bat file inside a lint folder of my project which I will create in the next step. Additionally I disable ‘Generate Makefiles automatically‘:

Builder Settings for PC-lint batch file

CodeWarrior for MCU10.2 uses parallel builds by default. This would add -j6 as option to the command line. In order to disable this, I configure project specific settings in the Build Behaviour tab:

Custom Build Behaviour

Step 2: Batch file

To separate the lint files from the rest of my build and project, I create a lint sub-folder inside my project root with a do_lint.bat batch file:

do_lint batch file

The do_lint.bat has following content:

@rem The arguments for this batch file: 
@rem %1: The path to the project folder
@rem %2: The path to the CodeWarrior installation folder
@rem ------------------------------------------------------
@rem Path to my project folder
SET PROJ_PATH=%1
@rem Path to CodeWarrior installation folder (which is e.g. "C:\Freescale\CW MCU v10.2\eclipse\..\MCU")
SET CW_PATH=%2
@rem Path to lint-nt.exe
SET LINT_EXE=C:\lint\lint-nt.exe
@rem Path to my lint configuration files
SET LOCAL_LNT_FILES=C:\Freescale\PC-lint\fsl_lnt
@rem Path to my local lint folder inside the project
SET PROJ_LINT_PATH=%PROJ_PATH%\lint
@rem Lint configuration files and includes
SET LNT_INCLUDES=-i"%LOCAL_LNT_FILES%" "%LOCAL_LNT_FILES%\co-mwhc08.lnt" -i%LOCAL_LNT_FILES%
@rem --------------- Run PC-lint ---------------------------
%LINT_EXE% %LNT_INCLUDES% %PROJ_LINT_PATH%\proj_options.lnt %PROJ_LINT_PATH%\proj_files.lnt -vf

The batch file is called from eclipse with two arguments (%1 and %2): with the path to the project folder and the path to the CodeWarrior installation folder. I assign them to local variables (PROJ_PATH and CW_PATH) so I can use them inside the .lnt files. To know where my lint compiler is, I use LINT_EXE. I store my lint configuration files outside of the PC-lint installation folder, that’s why I have defined a path variable for this: LOCAL_LINT_FILES. PROJ_LINT_PATH contains the project sub-folder with all my batch and lint files for the project. In LNT_INCLUDES I specify my compiler lint configuration file, plus where lint shall search for my lint configuration files. Finally it calls the lint executable with the lint include files, plus two files: the project options (proj_options.lnt) and the project files (proj_files.lnt). I explain these files in Step 4.

Step 3: List of Files

I have created a file proj_files.lnt file inside my project:

File listing the files to lint

This file has all my source files listed. And because I have defined environment variables like PROJ_PATH, I can use it here:

%PROJ_PATH%\Sources\main.c 
%PROJ_PATH%\Sources\Events.c

Step 4: Passing the options

What is missing are the project specific options: I add them to the proj_options.lnt file:

Project Options File

In this file I add with the -i PC-lint option all the paths where it can find my files:

// Include paths used
-i%PROJ_PATH%
-i%PROJ_PATH%\Sources
-i%PROJ_PATH%\Generated_Code
-i%CW_PATH%\lib\hc08c\include

Additionally I specify all the global options, e.g. to inhibit messages:

// inhibit messages for Processor Expert libraries
-elib(19, 10)
-e766
+libh(Events.h, Cpu.h)

Step 5: Defining the message format

Last but not least: I need to tell PC-lint how to format the messages so they end up properly in the eclipse Problems view. I add them as well to the proj_options.lnt:

// Coerce messages for Eclipse
-hF1
+ffn
// Normally my format is defined as follows:
//-"format=%(\q%f\q %l %C%) %t %n: %m"
// For eclipse-usage, the GCC error format is necessary,
// since we have only the default eclipse error parser available.
-"format=%(%f:%l:%C:%) %t %n: %m"
// Enable warning 831 if you are interested.
-frl
// Do not break lines
-width(0) 
// And make sure no foreign includes change the format
+flm

Step 5: Linting in action

Time to see how this works! As I have set up a separate build configuration to lint my files, I can run it like any other build configuration:

Build my lint configuration

The example below shows several lint errors for main.c. The messages show up in the Problems view, and are listed as well in the Console view:

Linting in action

Summary

The approach presented here does not need any other eclipse plugin. It is using a batch file, and uses a brute force approach: it will lint all files regardless if they have changed or not. This could be improved with a make file approach as outlined here. The approach presented here requires some setup, is pretty simple, and routes all lint messages to the Problems view. If I want to use more of a plugin approach, then the Linticator plugin is the alternative.

Thanks to Catherine for providing a lot of good ideas used in this article!

Happy linting