FnLoC - Counts Logical Lines of Code

Counts logical lines of code and functions in C and C++ source code files.

Copyright 2018-2019, Richard Romig

Licensed under the GNU General Public License, version 2.0.

Description:

1. FnLoC is a program that runs from a command-line which counts logical lines of code in C and C++ source code files, disregarding comments and blank lines. It also counts and lists functions by name displays their respective lines of code counts. The program assumes that the code is written according to modern C coding standards as illustrated in The C Programming Language, 2nd edition by Brian W. Kernighan & Dennis M. Ritchie. Comments and blank lines are not counted as lines of code. The programs takes into account both C and C++ style comments. Lines containing only opening or closing braces ({}) are not counted as lines of code.
2. LLoC is an accompanying program that simply counts logical lines of source code, disregarding blank lines and comments without the breakdown into functions.
3. The loc2file Bash script acts as a wrapper for FnLoC and LLoC. It displays the output from FnLoC to the screen as it writes the data to a text file with a .loc extension. If there is a matching header file, it will be run through LLoC with the output appended to the file.
4. FnLoC and LLoC are standalone programs with no known dependencies and were written using only standard C libraries.
5. Project source files:

File	Notes
fnloc.c	FnLoC source file
fnloc.h	FnLoC header file
lloc.c	LLoC source file
lloc.h	LLoC header file
lstates.c	common functions for both fnloc and lloc
lsstates.h	common declarations for both fnloc and lloc
Makefile	FnLoC, LLoC make file
loc2file	Bash script wrapper
SHA256sum.txt	Checksum file for the .deb package

Compiling from source:

1. On a Linux system, be sure GCC, binutils, glibc, and build-essentials are installed.

2. Compile the code using the Makefile (recommended).

   make Makefile
   

3. The Makefile is set up to use gcc. If you use a different C compiler, change the CC variable as appropriate.

4. The Makefile has not been tested with gcc in MinGW on Windows.

Installation:

1. In Debian-based distributions (Ubuntu, Mint, etc.) FnLoC can be installed from the .deb package using gdebi or dpkg.

   sudo gdebi fnloc_2.3.0_amd64.deb
   sudo dpkg -i fnloc_2.3.0_amd64.deb
   

2. The FnLoC files will be installed to the following directories:

Files	Location
Executable files (fnloc, lloc, and loc2file)	/usr/local/bin/
Source code files	/usr/local/src/fnloc/
Documentation files	/usr/local/doc/fnloc/

3. For other Linux distributions or 32-bit systems, download the source files and scripts (optional), compile from source, and run fnloc-install.sh.

Program removal:

1. If installed from fnloc.deb, you can remove the software via your system's Software Center/Manager or the Synaptic Package manager. You can remove the software from the command line with one of the following commands:

   sudo apt remove fnloc
   sudo dpkg -- remove fnloc
   

2. If installed using fnloc-install.sh, use the fnloc-uninstall.sh script.

3. FnLoC can be removed manually by deleting the installed files from their respective directories.

Syntax

1. To display the lines of code data of a C source code file run the following command from a terminal:

   • If you are in same directory as the targeted source code file:

     fnloc sourcefile.c
     lloc sourcefile.c
     

   • Or include the path to your source code:

     fnloc /path/to/sourcefile.c
     lloc  /path/to/sourcefile.c
     

   • The results can be redirected to a text file with the following command:

     fnloc sourcefile.c > sourcefile.loc
     lloc sourcefile.c > sourcefile.loc
     

   • The results can be diplayed to both the screen and redirected to a file with the following command:

     fnloc sourcefile.c | tee sourcefile.loc
     lloc sourcefile.c | tee sourcefile.loc
     

   • Alternatively, you can use loc2file to display the output to the screen while redirecting it to a text file with the .loc extension.

     log2file mysource.c
     

   • Adding -h or --help after either program name displays the program syntax:

     fnloc -h
     fnloc --help
     

   • If you don't include an argument or if the program fails to open the file passed as an argument it will also call up the help function.

Program Limitations

1. For FnLoC functions are expected to be in the following style:

        int function_name(int x, int y)
        {
            statements....
        }

   • This is the format recommended by Linus Torvalds in Linux Kernel Coding Style and is based on the style used by K&R in 'The C Programming Language, 2nd Edition'.
   • If the opening brace '{' is on the same line as the function name and parameters, it will not be seen as a function. The lines of code will be counted but as code outside of a function.
   • The program will properly count and display function headers that are split over two lines. Function headers should be limited to one or two lines of less than 128 characters each. The buffer limit is set to 128 characters. However, restraining function headers to a single line and 80 characters or less is a good practice.

2. Data structures should be in the following style:

        struct {
           int len;
           char* str;
        } data;

   • This is the style used by Kernighan & Ritchie in The C Programming Language, 2nd edition.

   • The GNU C coding standard suggests placing the opening brackets are at the beginning of a line. However, FnLoC will incorrectly identify a structure written in this style as a function.

   • In data structure declarations such as arrays or enumerated types in which the data elements are delimited by commas, the elements inside the braces are not counted if they are not on the same line as a brace.

        int days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        /* counted as a single line of code. */
     
        int days[12] = { 31, 28, 31, 30, 31, 30,
                31, 31, 30, 31, 30, 31 };
        /* counted as two lines of code */
     
        int days[12] = {
                31, 28, 31, 30, 31, 30,
                31, 31, 30, 31, 30, 31 };
        /* also counted as two lines of code (the first and last lines) */

3. Conditional statements, for loops and while loops without braces and only one statement following are counted as one line of code.

        if ( condition )
                action;
        /* This is seen as a one logical line of code */
   
        for ( i=1; i < 10; i++ )
                if (condition)
                    action;
        /* This is seen as a one logical line of code */
   
        while ( condition )
                action;
        /* This is seen as a one logical line of code */
   
        do
                action;
        while ( condition );
        /* This is seen as two logical lines of code */
   
        if ( condition )
        {
            action1;
            action2;
        }
        else
            action3;
        /* This is seen as 4 logical lines of code: (1) if ( condition ), (2) action1,
           (3) action2, (4) else-action3 */

4. Conditional and loop statements (if, else, for, while, do-while) where the opening brace is the first non-whtespace character on the line immediately following are counted as a line of code. Conditional statements and loop constructs can have the opening brace at either the end of the line or on the following line as long as it is not the very first character of the line (buffer[0]).

        while ( condition )
        {
                action1;
                action2;
        }
   
        while ( condition ) {
                action1;
                action2;
        }

5. LLoC is more lenient about coding style than FnLoC since it isn't concerned with the syntax for functions. However, data structure definitions, particularly those for arrays and enumerated types are counted exacly the same.

6. On Linux systems, the programs may not correctly count in source files that were created with DOS or Windows text editors because they may embed carriage returns throughout the file. This can be remedied by cleaning them out of the DOS/Windows source files using the following command:

   sed -i.bak -e 's/\r//g' sourcefile
   

   • The -i.bak flag creates a backup of the original file.
   • There are other methods such as the tr command but I found that sed works quite well.

Feedback:

Feel free to contact me with comments and suggestions for FnLoC. Also feel free to share any code or ideas that will help me improve this program. I can be reached through my blog, Twitter, and email.

• GitHub
• Rick's Tech Stuff
• Twitter (@ludditegeek)
• Email: rick.romig@gmail.com or rick.romig@mymetronet.net

Richard Romig 17 July 2024

DISCLAIMER

THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL I BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS AND SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.