diff options
| -rw-r--r-- | Makefile | 7 | ||||
| -rwxr-xr-x | scripts/headerdep.pl | 193 |
2 files changed, 199 insertions, 1 deletions
@@ -1026,6 +1026,10 @@ include/linux/version.h: $(srctree)/Makefile FORCE include/linux/utsrelease.h: include/config/kernel.release FORCE $(call filechk,utsrelease.h) +PHONY += headerdep +headerdep: + $(Q)find include/ -name '*.h' | xargs --max-args 1 scripts/headerdep.pl + # --------------------------------------------------------------------------- PHONY += depend dep @@ -1274,7 +1278,8 @@ help: @echo ' versioncheck - Sanity check on version.h usage' @echo ' includecheck - Check for duplicate included header files' @echo ' export_report - List the usages of all exported symbols' - @echo ' headers_check - Sanity check on exported headers'; \ + @echo ' headers_check - Sanity check on exported headers' + @echo ' headerdep - Detect inclusion cycles in headers'; \ echo '' @echo 'Kernel packaging:' @$(MAKE) $(build)=$(package-dir) help diff --git a/scripts/headerdep.pl b/scripts/headerdep.pl new file mode 100755 index 000000000000..97399da89ef2 --- /dev/null +++ b/scripts/headerdep.pl @@ -0,0 +1,193 @@ +#! /usr/bin/perl +# +# Detect cycles in the header file dependency graph +# Vegard Nossum <vegardno@ifi.uio.no> +# + +use strict; +use warnings; + +use Getopt::Long; + +my $opt_all; +my @opt_include; +my $opt_graph; + +&Getopt::Long::Configure(qw(bundling pass_through)); +&GetOptions( + help => \&help, + version => \&version, + + all => \$opt_all, + I => \@opt_include, + graph => \$opt_graph, +); + +push @opt_include, 'include'; +my %deps = (); +my %linenos = (); + +my @headers = grep { strip($_) } @ARGV; + +parse_all(@headers); + +if($opt_graph) { + graph(); +} else { + detect_cycles(@headers); +} + + +sub help { + print "Usage: $0 [options] file...\n"; + print "\n"; + print "Options:\n"; + print " --all\n"; + print " --graph\n"; + print "\n"; + print " -I includedir\n"; + print "\n"; + print "To make nice graphs, try:\n"; + print " $0 --graph include/linux/kernel.h | dot -Tpng -o graph.png\n"; + exit; +} + +sub version { + print "headerdep version 2\n"; + exit; +} + +# Get a file name that is relative to our include paths +sub strip { + my $filename = shift; + + for my $i (@opt_include) { + my $stripped = $filename; + $stripped =~ s/^$i\///; + + return $stripped if $stripped ne $filename; + } + + return $filename; +} + +# Search for the file name in the list of include paths +sub search { + my $filename = shift; + return $filename if -f $filename; + + for my $i (@opt_include) { + my $path = "$i/$filename"; + return $path if -f $path; + } + + return undef; +} + +sub parse_all { + # Parse all the headers. + my @queue = @_; + while(@queue) { + my $header = pop @queue; + next if exists $deps{$header}; + + $deps{$header} = [] unless exists $deps{$header}; + + my $path = search($header); + next unless $path; + + open(my $file, '<', $path) or die($!); + chomp(my @lines = <$file>); + close($file); + + for my $i (0 .. $#lines) { + my $line = $lines[$i]; + if(my($dep) = ($line =~ m/^#\s*include\s*<(.*?)>/)) { + push @queue, $dep; + push @{$deps{$header}}, [$i + 1, $dep]; + } + } + } +} + +sub print_cycle { + # $cycle[n] includes $cycle[n + 1]; + # $cycle[-1] will be the culprit + my $cycle = shift; + + # Adjust the line numbers + for my $i (0 .. $#$cycle - 1) { + $cycle->[$i]->[0] = $cycle->[$i + 1]->[0]; + } + $cycle->[-1]->[0] = 0; + + my $first = shift @$cycle; + my $last = pop @$cycle; + + my $msg = "In file included"; + printf "%s from %s,\n", $msg, $last->[1] if defined $last; + + for my $header (reverse @$cycle) { + printf "%s from %s:%d%s\n", + " " x length $msg, + $header->[1], $header->[0], + $header->[1] eq $last->[1] ? ' <-- here' : ''; + } + + printf "%s:%d: warning: recursive header inclusion\n", + $first->[1], $first->[0]; +} + +# Find and print the smallest cycle starting in the specified node. +sub detect_cycles { + my @queue = map { [[0, $_]] } @_; + while(@queue) { + my $top = pop @queue; + my $name = $top->[-1]->[1]; + + for my $dep (@{$deps{$name}}) { + my $chain = [@$top, [$dep->[0], $dep->[1]]]; + + # If the dep already exists in the chain, we have a + # cycle... + if(grep { $_->[1] eq $dep->[1] } @$top) { + print_cycle($chain); + next if $opt_all; + return; + } + + push @queue, $chain; + } + } +} + +sub mangle { + $_ = shift; + s/\//__/g; + s/\./_/g; + s/-/_/g; + $_; +} + +# Output dependency graph in GraphViz language. +sub graph { + print "digraph {\n"; + + print "\t/* vertices */\n"; + for my $header (keys %deps) { + printf "\t%s [label=\"%s\"];\n", + mangle($header), $header; + } + + print "\n"; + + print "\t/* edges */\n"; + for my $header (keys %deps) { + for my $dep (@{$deps{$header}}) { + printf "\t%s -> %s;\n", + mangle($header), mangle($dep->[1]); + } + } + + print "}\n"; +} |