====== Code review utility for software porting projects ======

Assume this situation. You are assigned to port a code to a new
hardware/os platform. Generally this involves picking the necessary
files for implementing the desired functionality and porting these set
of files to the new platform. While doing this, several things happen. First, you usually do not keep the same hierarchy structure, you may for example put all your .c files in a directory called src and all your includes in another directory called inc. You would also modify the sources so that the code compiles in the new build environment.

In organizations that give importance to code quality. Code review
operations help minimize faults and bugs in new software. On of the
methods for reviewing code in software porting projects is to create
a diff between the original source tree (assumed bug free) and the
new/ported source tree.

This bash script is an utility that can be used to create such diffs. The resulting output is an HTML file easy to read. It can be used by team leaders to review and validate the changes in the source code made by team members.

===== Scrip for generating diffs =====

This utility can be used for codereviews when porting software to a new platform. The utility matches source files in the new source tree with source files in the original source tree and creates a diff for each. The result is formatted as an HTML file.

The outputs are as follows :

  * List of files and their path in the original source tree (filelist.txt)
  * A patch for each file against its original version (diffs)

The utility can search files in steps. This allows the use of prioritary search paths if a source file can be found in different locations in the original source tree. For example, if most of our files come from dir1, but dir2 comes first during the search operation, we can force the utility to use dir1 to lookup the original source files by doing a search pass in dir1. Files that were matched in the first pass will not be looked up in the following passes.

Files that can not be found automatically can be handled manually. For this  create a file called exceptions.txt and add entries as follows :

   filename:path/to/original/version

The utility will not lookup files in exceptions.txt. only diffs will be generated.
 
<code sh>

#!/bin/bash

# First match files against dir1

ORIGNIALSOURCE=~/originalsourcetree
INDEX=0


function makelist {

echo creating file list
echo "" > filelist.txt

# First pass: look in DIR1

for file in src/*.c inc/*.h
do

base=`basename $file`

# process exceptions
res=`grep $base exceptions.txt`

if [ $res ]
then
echo skipping $base
continue
fi

echo -n "$base:" >> filelist.txt

find $ORIGNIALSOURCE/DIR1 -name $base -print | tr -d "\n" >> filelist.txt
echo >> filelist.txt
done

cat exceptions.txt >> filelist.txt

# Second pass: look in DIR2

echo "" > filelist2.txt

COUNT=0
while read line 
do

if [ "$line" = "" ]
then
continue
fi


base=`echo $line | cut -d":" -f1`
path=`echo $line | cut -d":" -f2`

if [ "$path" = "" ]
then
	
	echo -n $base: >> filelist2.txt
	find $ORIGNIALSOURCE/DIR2 -name $base -print | tr -d "\n" >> filelist2.txt
	echo >> filelist2.txt
	COUNT=`expr $COUNT + 1`
else 
	echo $base:$path >> filelist2.txt
fi

done <  filelist.txt


# Third pass: look in DIR3

echo "" > filelist3.txt

COUNT=0
while read line 
do

if [ "$line" = "" ]
then
continue
fi

base=`echo $line | cut -d":" -f1`
path=`echo $line | cut -d":" -f2`

if [ "$path" = "" ]
then
	
	echo -n $base: >> filelist3.txt
	find $ORIGNIALSOURCE/DIR3 -name $base -print | tr -d "\n" >> filelist3.txt
	echo >> filelist3.txt
	COUNT=`expr $COUNT + 1`
else 
	echo $base:$path >> filelist3.txt
fi

done <  filelist2.txt



while read line 
do
if [ "$line" = "" ]
then
continue
fi

base=`echo $line | cut -d":" -f1`
path=`echo $line | cut -d":" -f2`
if [ "$path" = "" ]
then
	echo "$base @$line@ not found ! Aborting."
	exit -1
fi

done <  filelist3.txt


echo "file list generated (filelist.txt)"


mv filelist3.txt filelist.txt
rm filelist2.txt
}


# For each source/header file, make a diff with the original file and store the
# diff as filename.extension.diff

function makediff {

echo creating diffs

if ! [ -d diffs ] 
then
mkdir diffs
fi

while read line 
do
if [ "$line" = "" ]
then
continue
fi

base=`echo $line | cut -d":" -f1`
path=`echo $line | cut -d":" -f2`

if [ -f src/$base ]
then
diff  -uBwb $path src/$base > diffs/$base.diff
else
diff  -uBwb $path inc/$base > diffs/$base.diff
fi



done <  filelist.txt
}


# Build HTML output

function makehtml {
echo creating HTML

echo "<table border="1">" > diff.html

echo "<tr>" >> diff.html
echo "<th>File number</th>" >> diff.html
echo "<th>File name</th>" >> diff.html
echo "<th>Path</th>" >> diff.html
echo "<th>Diff</th>" >> diff.html
echo "<td>" >> diff.html

COUNT=0

while read line 
do
if [ "$line" = "" ]
then
continue
fi

COUNT=`expr $COUNT + 1`

base=`echo $line | cut -d":" -f1`
path=`echo $line | cut -d":" -f2`

echo "<tr>" >> diff.html
echo "<td>$COUNT</td>" >> diff.html
echo "<td>$base</td>" >> diff.html
echo "<td>$path</td>" >> diff.html
echo "<td>" >> diff.html
echo "<PRE>" >> diff.html
cat diffs/$base.diff >> diff.html
echo "</PRE>" >> diff.html
echo "<td>"  >> diff.html
echo "</tr>" >> diff.html

done <  filelist.txt

echo "</table>" >> diff.html

}

makelist
makediff
makehtml
</code>





{{tag>howto coding}}


~~DISCUSSION~~