Deleting comments in c or java code by awk scripts
Last night , I attended writting examination for Bai Du,There is a problem, ask us implement a state machine to deleting the comments in c code,I don't know how to implement. So I writte this awk script to handle this problem.
I test my scripts by about 10 000 lines c code ,it is reliable to deleting all comments,I also confirm it isn't delete c code but I just test it by a little code.
My classmate tell me, my scripts have some bugs ,but he just tell me there have some bugs.If you find there are some bugs ,please tell me the details.I will appreciate it.
Following commants, my script can delete it ,I had many testing.
1. int tag = 0; //something about comments
2. //something about comments
3. /* something about comments */
4. int tag = 0, /* someting about comments */ mytag = 0;
5. /* something
about
comments */
6 /* something
* about
* comments
*/
My awk script is following:
{
##The befor line don't contains /*
if(deletetag == 0){
mathc($0,/\/\/)
##This line contains //
if ( RLENGTH == 2)
{
code = 0
##There are some c code befor //
if( RSTART > 0) {
print substr($0,0,RSTART-1)
}
} else {
match($0,/\/\*/)
tmpstart = RSTART
##This line contains /*
if (RLENGTH == 2){
code=2
match($0,/\*\//)
##This line contains */
if (RLENGTH == 2){
print substr($0,0,tmpstart-1) substr($0,RSTART + RLENGTH +1)
} else {
deletetag=1
}
}
}
} else if (deletetag == 1){ ##Befor line contains /*
code=0
match($0,/\*\//)
##This line contians */
if(RLENGTH == 2){
deletetag=0
}
}
##This line don't contians // and /* and The befor line don't contians /*, so print this line
if ( code ==1){
print $0
}
code=1
}
If my awk scripts have some bugs ,please mail me lijidong@ict.ac.cn or qinqiqili@163.com , I will appreciate it. Thanks.