nexmon – Rev 1
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#!/usr/bin/env perl
#
# Copyright 2013, William Meier (See AUTHORS file)
#
# Validate hf_... and ei_... usage for a dissector file;
#
# Usage: checkhf.pl [--debug=?] <file or files>
#
# Wireshark - Network traffic analyzer
# By Gerald Combs <gerald@wireshark.org>
# Copyright 1998 Gerald Combs
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
## Note: This program is a re-implementation of the
## original checkhf.pl written and (C) by Joerg Mayer.
## The overall objective of the new implementation was to reduce
## the number of false positives which occurred with the
## original checkhf.pl
##
## This program can be used to scan original .c source files or source
## files which have been passed through a C pre-processor.
## Operating on pre-processed source files is optimal; There should be
## minimal false positives.
## If the .c input is an original source file there may very well be
## false positives/negatives due to the fact that the hf_... variables & etc
## may be created via macros.
##
## ----- (The following is extracted from the original checkhf.pl with thanks to Joerg) -------
## Example:
## ~/work/wireshark/trunk/epan/dissectors> ../../tools/checkhf.pl packet-afs.c
## Unused entry: packet-afs.c, hf_afs_ubik_voteend
## Unused entry: packet-afs.c, hf_afs_ubik_errcode
## Unused entry: packet-afs.c, hf_afs_ubik_votetype
## ERROR: NO ARRAY: packet-afs.c, hf_afs_fs_ipaddr
##
## or checkhf.pl packet-*.c, which will check all the dissector files.
##
## NOTE: This tool currently generates false positives!
##
## The "NO ARRAY" messages - if accurate - points to an error that will
## cause (t|wire)shark to report a DISSECTOR_BUG when a packet containing
## this particular element is being dissected.
##
## The "Unused entry" message indicates the opposite: We define an entry but
## never use it (e.g., in a proto_...add... function).
## ------------------------------------------------------------------------------------
# ------------------------------------------------------------------------------------
# Main
#
# Logic:
# 1. Clean the input: remove blank lines, comments, quoted strings and code under '#if 0'.
# 2. hf_defs:
# Find (and remove from input) list of hf_... variable
# definitions ('static? g?int hf_... ;')
# 2. hf_array_entries:
# Find (and remove from input) list of hf_... variables
# referenced in the hf[] entries;
# 3. hf_usage:
# From the remaining input, extract list of all strings of form hf_...
# (which may include strings which are not actually valid
# hf_... variable references).
# 4. Checks:
# If entries in hf_defs not in hf_usage then "unused" (for static hf_defs only)
# If entries in hf_defs not in hf_array_entries then "ERROR: NO ARRAY";
use strict;
use warnings;
use Getopt::Long;
my $help_flag = '';
my $debug = 0; # default: off; 1=cmt; 2=#if0; 3=hf_defs; 4=hf_array_entries; 5=hfusage (See code)
my $sts = GetOptions(
'debug=i' => \$debug,
'help|?' => \$help_flag
);
if (!$sts || $help_flag || !$ARGV[0]) {
usage();
}
my $error = 0;
while (my $filename = $ARGV[0]) {
shift;
my ($file_contents);
my (%hf_defs, %hf_static_defs, %hf_array_entries, %hf_usage);
my ($unused_href, $no_array_href);
my (%ei_defs, %ei_static_defs, %ei_array_entries, %ei_usage);
my ($unused_ei, $no_array_ei);
read_file(\$filename, \$file_contents);
remove_comments (\$file_contents, $filename);
remove_blank_lines (\$file_contents, $filename);
remove_quoted_strings(\$file_contents, $filename);
remove_if0_code (\$file_contents, $filename);
find_remove_hf_defs (\$file_contents, $filename, \%hf_defs);
find_remove_hf_array_entries (\$file_contents, $filename, \%hf_array_entries);
find_remove_proto_get_id_hf_assignments(\$file_contents, $filename, \%hf_array_entries);
find_hf_usage (\$file_contents, $filename, \%hf_usage);
find_remove_ei_defs (\$file_contents, $filename, \%ei_defs);
find_remove_ei_array_entries (\$file_contents, $filename, \%ei_array_entries);
find_ei_usage (\$file_contents, $filename, \%ei_usage);
# Tests (See above)
# 1. Are all the static hf_defs and ei_defs entries in hf_usage and ei_usage?
# if not: "Unused entry:"
#
# create a hash containing entries just for the static definitions
@hf_static_defs{grep {$hf_defs{$_} == 0} keys %hf_defs} = (); # All values in the new hash will be undef
@ei_static_defs{grep {$ei_defs{$_} == 0} keys %ei_defs} = (); # All values in the new hash will be undef
$unused_href = diff_hash(\%hf_static_defs, \%hf_usage);
remove_hf_pid_from_unused_if_add_oui_call(\$file_contents, $filename, $unused_href);
$unused_ei = diff_hash(\%ei_static_defs, \%ei_usage);
print_list("Unused href entry: $filename: ", $unused_href);
print_list("Unused ei entry: $filename: ", $unused_ei);
# 2. Are all the hf_defs and ei_ entries (static and global) in [hf|ei]_array_entries ?
# (Note: if a static hf_def or ei is "unused", don't check for same in [hf|ei]_array_entries)
# if not: "ERROR: NO ARRAY"
## Checking for missing global defs currently gives false positives
## So: only check static defs for now.
## $no_array_href = diff_hash(\%hf_defs, \%hf_array_entries);
$no_array_href = diff_hash(\%hf_static_defs, \%hf_array_entries);
$no_array_href = diff_hash($no_array_href, $unused_href); # Remove "unused" hf_... from no_array list
$no_array_ei = diff_hash(\%ei_static_defs, \%ei_array_entries);
$no_array_ei = diff_hash($no_array_ei, $unused_ei); # Remove "unused" ei_... from no_array list
print_list("ERROR: NO ARRAY: $filename: ", $no_array_href);
print_list("ERROR: NO ARRAY: $filename: ", $no_array_ei);
if ((keys %{$no_array_href}) != 0) {
$error += 1;
}
if ((keys %{$no_array_ei}) != 0) {
$error += 1;
}
}
exit (($error == 0) ? 0 : 1); # exit 1 if ERROR
# ---------------------------------------------------------------------
#
sub usage {
print "Usage: $0 [--debug=n] Filename [...]\n";
exit(1);
}
# ---------------------------------------------------------------------
# action: read contents of a file to specified string
# arg: filename_ref, file_contents_ref
sub read_file {
my ($filename_ref, $file_contents_ref) = @_;
die "No such file: \"${$filename_ref}\"\n" if (! -e ${$filename_ref});
# delete leading './'
${$filename_ref} =~ s{ ^ [.] / } {}xmso;
# Read in the file (ouch, but it's easier that way)
open(my $fci, "<:crlf", ${$filename_ref}) || die("Couldn't open ${$filename_ref}");
${$file_contents_ref} = do { local( $/ ) ; <$fci> } ;
close($fci);
return;
}
# ---------------------------------------------------------------------
# action: Create a hash containing entries in 'a' that are not in 'b'
# arg: a_href, b_href
# returns: pointer to hash
sub diff_hash {
my ($a_href, $b_href) = @_;
my %diffs;
@diffs{grep {! exists $b_href->{$_}} keys %{$a_href}} = (); # All values in the new hash will be undef
return \%diffs;
}
# ---------------------------------------------------------------------
# action: print a list
# arg: hdr, list_href
sub print_list {
my ($hdr, $list_href) = @_;
print
map {"$hdr$_\n"}
sort
keys %{$list_href};
return;
}
# ------------
# action: remove blank lines from input string
# arg: code_ref, filename
sub remove_blank_lines {
my ($code_ref, $filename) = @_;
${$code_ref} =~ s{ ^ \s* \n ? } {}xmsog;
return;
}
# ------------
# action: remove comments from input string
# arg: code_ref, filename
sub remove_comments {
my ($code_ref, $filename) = @_;
# The below Regexp is based on one from:
# http://aspn.activestate.com/ASPN/Cookbook/Rx/Recipe/59811
# It is in the public domain.
# A complicated regex which matches C-style comments.
my $c_comment_regex = qr{ / [*] [^*]* [*]+ (?: [^/*] [^*]* [*]+ )* / }xmso;
${$code_ref} =~ s{ $c_comment_regex } {}xmsog;
($debug == 1) && print "==> After Remove Comments: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ------------
# action: remove quoted strings from input string
# arg: code_ref, filename
sub remove_quoted_strings {
my ($code_ref, $filename) = @_;
# A regex which matches double-quoted strings.
# 's' modifier added so that strings containing a 'line continuation'
# ( \ followed by a new-line) will match.
my $double_quoted_str = qr{ (?: ["] (?: \\. | [^\"\\])* ["]) }xmso;
# A regex which matches single-quoted strings.
my $single_quoted_str = qr{ (?: ['] (?: \\. | [^\'\\])* [']) }xmso;
${$code_ref} =~ s{ $double_quoted_str | $single_quoted_str } {}xmsog;
($debug == 1) && print "==> After Remove quoted strings: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# -------------
# action: remove '#if 0'd code from the input string
# args code_ref, filename
#
# Essentially: Use s//patsub/meg to pass each line to patsub.
# patsub monitors #if/#if 0/etc and determines
# if a particular code line should be removed.
# XXX: This is probably pretty inefficient;
# I could imagine using another approach such as converting
# the input string to an array of lines and then making
# a pass through the array deleting lines as needed.
{ # block begin
my ($if_lvl, $if0_lvl, $if0); # shared vars
sub remove_if0_code {
my ($code_ref, $filename) = @_;
# First see if any '#if 0' lines which need to be handled
if (${$code_ref} !~ m{ \# \s* if \s+ 0 }xmso ) {
return;
}
my ($preproc_regex) = qr{
( # $1 [complete line)
^
(?: # non-capturing
\s* \# \s*
(if \s 0| if | else | endif) # $2 (only if #...)
) ?
[^\n]*
\n ?
)
}xmso;
($if_lvl, $if0_lvl, $if0) = (0,0,0);
${$code_ref} =~ s{ $preproc_regex } { patsub($1,$2) }xmsoeg;
($debug == 2) && print "==> After Remove if0: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
sub patsub {
if ($debug == 99) {
print "-->$_[0]\n";
(defined $_[1]) && print " >$_[1]<\n";
}
# #if/#if 0/#else/#endif processing
if (defined $_[1]) {
my ($if) = $_[1];
if ($if eq 'if') {
$if_lvl += 1;
}
elsif ($if eq 'if 0') {
$if_lvl += 1;
if ($if0_lvl == 0) {
$if0_lvl = $if_lvl;
$if0 = 1; # inside #if 0
}
}
elsif ($if eq 'else') {
if ($if0_lvl == $if_lvl) {
$if0 = 0;
}
}
elsif ($if eq 'endif') {
if ($if0_lvl == $if_lvl) {
$if0 = 0;
$if0_lvl = 0;
}
$if_lvl -= 1;
if ($if_lvl < 0) {
die "patsub: #if/#endif mismatch"
}
}
return $_[0]; # don't remove preprocessor lines themselves
}
# not preprocessor line: See if under #if 0: If so, remove
if ($if0 == 1) {
return ''; # remove
}
return $_[0];
}
} # block end
# ---------------------------------------------------------------------
# action: Add to hash an entry for each
# 'static? g?int hf_...' definition (including array names)
# in the input string.
# The entry value will be 0 for 'static' definitions and 1 for 'global' definitions;
# Remove each definition found from the input string.
# args: code_ref, filename, hf_defs_href
# returns: ref to the hash
sub find_remove_hf_defs {
my ($code_ref, $filename, $hf_defs_href) = @_;
# Build pattern to match any of the following
# static? g?int hf_foo = -1;
# static? g?int hf_foo[xxx];
# static? g?int hf_foo[xxx] = {
# p1: 'static? g?int hf_foo'
my $p1_regex = qr{
^
\s*
(static \s+)?
g?int
\s+
(hf_[a-zA-Z0-9_]+) # hf_..
}xmso;
# p2a: ' = -1;'
my $p2a_regex = qr{
\s* = \s*
(?:
- \s* 1
)
\s* ;
}xmso;
# p2b: '[xxx];' or '[xxx] = {'
my $p2b_regex = qr/
\s* \[ [^\]]+ \] \s*
(?:
= \s* [{] | ;
)
/xmso;
my $hf_def_regex = qr{ $p1_regex (?: $p2a_regex | $p2b_regex ) }xmso;
while (${$code_ref} =~ m{ $hf_def_regex }xmsog) {
#print ">%s< >$2<\n", (defined $1) ? $1 ; "";
$hf_defs_href->{$2} = (defined $1) ? 0 : 1; # 'static' if $1 is defined.
}
($debug == 3) && debug_print_hash("VD: $filename", $hf_defs_href); # VariableDefinition
# remove all
${$code_ref} =~ s{ $hf_def_regex } {}xmsog;
($debug == 3) && print "==> After remove hf_defs: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ---------------------------------------------------------------------
# action: Add to hash an entry (hf_...) for each hf[] entry.
# Remove each hf[] entries found from the input string.
# args: code_ref, filename, hf_array_entries_href
sub find_remove_hf_array_entries {
my ($code_ref, $filename, $hf_array_entries_href) = @_;
# hf[] entry regex (to extract an hf_index_name and associated field type)
my $hf_array_entry_regex = qr /
[{]
\s*
& \s* ( [a-zA-Z0-9_]+ ) # &hf
(?:
\s* [[] [^]]+ []] # optional array ref
) ?
\s* , \s*
[{]
[^}]+
, \s*
(FT_[a-zA-Z0-9_]+) # field type
\s* ,
[^}]+
, \s*
(?:
HFILL | HF_REF_TYPE_NONE
)
[^}]*
}
[\s,]*
[}]
/xmso;
# find all the hf[] entries (searching ${$code_ref}).
while (${$code_ref} =~ m{ $hf_array_entry_regex }xmsog) {
($debug == 98) && print "+++ $1 $2\n";
$hf_array_entries_href->{$1} = undef;
}
($debug == 4) && debug_print_hash("AE: $filename", $hf_array_entries_href); # ArrayEntry
# now remove all
${$code_ref} =~ s{ $hf_array_entry_regex } {}xmsog;
($debug == 4) && print "==> After remove hf_array_entries: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ---------------------------------------------------------------------
# action: Add to hash an entry (hf_...) for each hf_... var
# found in statements of the form:
# 'hf_... = proto_registrar_get_id_byname ...'
# 'hf_... = proto_get_id_by_filtername ...'
# Remove each such statement found from the input string.
# args: code_ref, filename, hf_array_entries_href
sub find_remove_proto_get_id_hf_assignments {
my ($code_ref, $filename, $hf_array_entries_href) = @_;
my $_regex = qr{ ( hf_ [a-zA-Z0-9_]+ )
\s* = \s*
(?: proto_registrar_get_id_byname | proto_get_id_by_filter_name )
}xmso;
my @hfvars = ${$code_ref} =~ m{ $_regex }xmsog;
if (@hfvars == 0) {
return;
}
# found:
# Sanity check: hf_vars shouldn't already be in hf_array_entries
if (defined @$hf_array_entries_href{@hfvars}) {
printf "? one or more of [@hfvars] initialized via proto_registrar_get_by_name() also in hf[] ??\n";
}
# Now: add to hf_array_entries
@$hf_array_entries_href{@hfvars} = ();
($debug == 4) && debug_print_hash("PR: $filename", $hf_array_entries_href);
# remove from input (so not considered as 'usage')
${$code_ref} =~ s{ $_regex } {}xmsog;
($debug == 4) && print "==> After remove proto_registrar_by_name: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ---------------------------------------------------------------------
# action: Add to hash all hf_... strings remaining in input string.
# arga: code_ref, filename, hf_usage_href
# return: ref to hf_usage hash
#
# The hash will include *all* strings of form hf_...
# which are in the input string (even strings which
# aren't actually vars).
# We don't care since we'll be checking only
# known valid vars against these strings.
sub find_hf_usage {
my ($code_ref, $filename, $hf_usage_href) = @_;
my $hf_usage_regex = qr{
\b ( hf_[a-zA-Z0-9_]+ ) # hf_...
}xmso;
while (${$code_ref} =~ m{ $hf_usage_regex }xmsog) {
#print "$1\n";
$hf_usage_href->{$1} += 1;
}
($debug == 5) && debug_print_hash("VU: $filename", $hf_usage_href); # VariableUsage
return;
}
# ---------------------------------------------------------------------
# action: Remove from 'unused' hash an instance of a variable named hf_..._pid
# if the source has a call to llc_add_oui() or ieee802a_add_oui().
# (This is rather a bit of a hack).
# arga: code_ref, filename, unused_href
sub remove_hf_pid_from_unused_if_add_oui_call {
my ($code_ref, $filename, $unused_href) = @_;
if ((keys %{$unused_href}) == 0) {
return;
}
my @hfvars = grep { m/ ^ hf_ [a-zA-Z0-9_]+ _pid $ /xmso} keys %{$unused_href};
if ((@hfvars == 0) || (@hfvars > 1)) {
return; # if multiple unused hf_..._pid
}
if (${$code_ref} !~ m{ llc_add_oui | ieee802a_add_oui }xmso) {
return;
}
# hf_...pid unused var && a call to ..._add_oui(); delete entry from unused
# XXX: maybe hf_..._pid should really be added to hfUsed ?
delete @$unused_href{@hfvars};
return;
}
# ---------------------------------------------------------------------
# action: Add to hash an entry for each
# 'static? expert_field ei_...' definition (including array names)
# in the input string.
# The entry value will be 0 for 'static' definitions and 1 for 'global' definitions;
# Remove each definition found from the input string.
# args: code_ref, filename, hf_defs_href
# returns: ref to the hash
sub find_remove_ei_defs {
my ($code_ref, $filename, $ei_defs_eiref) = @_;
# Build pattern to match any of the following
# static? expert_field ei_foo = -1;
# static? expert_field ei_foo[xxx];
# static? expert_field ei_foo[xxx] = {
# p1: 'static? expert_field ei_foo'
my $p1_regex = qr{
^
\s*
(static \s+)?
expert_field
\s+
(ei_[a-zA-Z0-9_]+) # ei_..
}xmso;
# p2a: ' = EI_INIT;'
my $p2a_regex = qr{
\s* = \s*
(?:
EI_INIT
)
\s* ;
}xmso;
# p2b: '[xxx];' or '[xxx] = {'
my $p2b_regex = qr/
\s* \[ [^\]]+ \] \s*
(?:
= \s* [{] | ;
)
/xmso;
my $ei_def_regex = qr{ $p1_regex (?: $p2a_regex | $p2b_regex ) }xmso;
while (${$code_ref} =~ m{ $ei_def_regex }xmsog) {
#print ">%s< >$2<\n", (defined $1) ? $1 ; "";
$ei_defs_eiref->{$2} = (defined $1) ? 0 : 1; # 'static' if $1 is defined.
}
($debug == 3) && debug_print_hash("VD: $filename", $ei_defs_eiref); # VariableDefinition
# remove all
${$code_ref} =~ s{ $ei_def_regex } {}xmsog;
($debug == 3) && print "==> After remove ei_defs: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ---------------------------------------------------------------------
# action: Add to hash an entry (ei_...) for each ei[] entry.
# Remove each ei[] entries found from the input string.
# args: code_ref, filename, ei_array_entries_href
sub find_remove_ei_array_entries {
my ($code_ref, $filename, $ei_array_entries_eiref) = @_;
# ei[] entry regex (to extract an ei_index_name and associated field type)
my $ei_array_entry_regex = qr /
{
\s*
& \s* ( [a-zA-Z0-9_]+ ) # &ei
(?:
\s* [ [^]]+ ] # optional array ref
) ?
\s* , \s*
{
# \s* "[^"]+" # (filter string has been removed already)
\s* , \s*
PI_[A-Z0-9_]+ # event group
\s* , \s*
PI_[A-Z0-9_]+ # event severity
\s* ,
[^,]* # description string (already removed) or NULL
, \s*
EXPFILL
\s*
}
\s*
}
/xs;
# find all the ei[] entries (searching ${$code_ref}).
while (${$code_ref} =~ m{ $ei_array_entry_regex }xsg) {
($debug == 98) && print "+++ $1\n";
$ei_array_entries_eiref->{$1} = undef;
}
($debug == 4) && debug_print_hash("AE: $filename", $ei_array_entries_eiref); # ArrayEntry
# now remove all
${$code_ref} =~ s{ $ei_array_entry_regex } {}xmsog;
($debug == 4) && print "==> After remove ei_array_entries: code: [$filename]\n${$code_ref}\n===<\n";
return;
}
# ---------------------------------------------------------------------
# action: Add to hash all ei_... strings remaining in input string.
# arga: code_ref, filename, ei_usage_eiref
# return: ref to ei_usage hash
#
# The hash will include *all* strings of form ei_...
# which are in the input string (even strings which
# aren't actually vars).
# We don't care since we'll be checking only
# known valid vars against these strings.
sub find_ei_usage {
my ($code_ref, $filename, $ei_usage_eiref) = @_;
my $ei_usage_regex = qr{
\b ( ei_[a-zA-Z0-9_]+ ) # ei_...
}xmso;
while (${$code_ref} =~ m{ $ei_usage_regex }xmsog) {
#print "$1\n";
$ei_usage_eiref->{$1} += 1;
}
($debug == 5) && debug_print_hash("VU: $filename", $ei_usage_eiref); # VariableUsage
return;
}
# ---------------------------------------------------------------------
sub debug_print_hash {
my ($title, $href) = @_;
##print "==> $title\n";
for my $k (sort keys %{$href}) {
my $h = defined($href->{$k}) ? $href->{$k} : "undef";
printf "%-40.40s %5.5s %s\n", $title, $h, $k;
}
}