ijalab has asked for the wisdom of the Perl Monks concerning the following question:

I have to write a perl script to go over the C code base and identify all the functions in each file and replace each function name with a keyword, for example, i have a file name 1.c 
int func1(struct commandId)
{
  do();
  return ( SUCCESS );
}
void func2(struct commandId)
{
  do();
  return ( SUCCESS );
}
float func3(struct commandId)
{
  do();
  return ( SUCCESS );
}

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My intention is to replace func1, func2, func3 with func1_main, func2_main, func3_main....I see lot of advices, but quite confused as I am very new to PERL as to which method i should follow. The code base is big and there are lot of files and other open close braces in if else statements etc.., so, i would like to know any parser that exist in PERL to do this intended function.

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Re: Identifying functions in a c file and replacing with a keyword
by marto (Cardinal) on Mar 18, 2013 at 09:51 UTC
[reply]
Re: Identifying functions in a c file and replacing with a keyword
by tobyink (Canon) on Mar 18, 2013 at 10:48 UTC 
    #!/usr/bin/env perl

use v5.12;
use C::Scan;
use Data::Dumper;
use File::Temp qw(tempfile);

# Create a C source file to parse...
my $code = <<'DATA';
int func_a ();
void func_b (int foo);
float func_c (int foo, float bar);
int func_d (char* baz) {
    return func_a(4);
}
DATA
my ($fh, $name) = tempfile();
print $fh $code;
close $fh;

# Let's see what's in the file
my $scan = "C::Scan"->new(filename => $name);

say "Declared functions:";
say for map $_->[1], @{ $scan->get("parsed_fdecls") };

say "Inline functions:";
say for map { /^\w+\s+(\w+)/s } @{ $scan->get("inlines") };

say "---";

# OK, let's make an array of those function names
my @funcs = (
    (map $_->[1], @{ $scan->get("parsed_fdecls") }),
    (map { /^\w+\s+(\w+)/s } @{ $scan->get("inlines") }),
);

print Dumper \@funcs;

say "---";

# Make a regexp out of that.
my $regexp = join "|", map quotemeta, @funcs;

# Let's do a search and replace on the original code
$code =~ s{($regexp)}{$1\_main}g;
say $code;

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    package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name
[reply]
[d/l]
      Sir, Thanks for the help. I am unable to install c::span module for windows xp.
[reply]
        I am unable to install c::span module for windows xp

        C::Scan builds, tests and installs fine for me on windows.
        What prevents you from installing it ?

        Cheers,
        Rob
[reply]
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