Shell Programming and Scripting

I need script code that does the following.

It would go into all the .c files in the current directory and in each file, it would copy the function headers for all the functions that are not static(don't begin with static) and stores them in one file with the word "extern" added at the beginning(if they are not already) and parameter names removed.

The output should look something like this:

Code:

/* file1.c */
extern Queue *newQueue(void);
extern void enqueue(Queue *, void *);
extern *void dequeue(Queue *);

/* file2.c */
extern StringBuffer *newStringBuffer(void);
extern void clear(StringBuffer *);
extern char *input(StringBuffer *, FILE *);

file1 and file2 would obviously be the names of the files. And each block would contain the functions in that file.

Extra: have #include'd in each source file, and remove redundant extern declarations from them.

Well, sed and shell easily do the first bit.

Code:

find ... -type f -name '*.c' | while read f
do
  e=$(
    sed '
      s/^[ \t]*//
      s/^extern[ \t][\ \t]*//
      /^[a-zA-Z0-9_]\{1,99\}(/{
        :loop
        /)/!{
          $d
          N
          s/\n[ \t]*/ /
          b loop
          }
        s/[ \t]\{1,99\}/ /g
        s/ \([,)]\)/\1/g
        s/ *\* */ */g
        s/[a-zA-Z0-9_]\{1,99\}\([,)]\)/\1/g
        s/^/extern /
        b
        }
      d
     ' $f
    )
 
  if [ "$e" != "" ]
  then
    echo "/* $f */
$e"
  fi
done >output

Narrative: find files, for each file $f, capute in e the output of the sed script on $f. The sed first clears any leading white space, any extern with white space, and detects a name with a ( tight on the name (if you have spaces, we need to remove them just before this). For that, it loops adding lines until there is a ')', but if eof shows up, deletes everything, then normalizes all white space to a single space, ensures one space before any asterisk and none after, ensures names end in ',' or ')' tight, removes the names, adds the extern, and writes out the product.

Not sure what the second thing is. Do you want every subroutine in its own file and and extern prototype in its place? Subroutine/file names might conflict, but that is a good practice. #include'ing subroutines is a step backward; learn to make a library mystuff.a using ar or even mystuff.so (dynamic) from that using gcc. Creating a shared and static library with the gnu compiler [gcc]