diff options
Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/util/symcheck.pl')
| -rwxr-xr-x | contrib/syslinux-4.02/gpxe/src/util/symcheck.pl | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/util/symcheck.pl b/contrib/syslinux-4.02/gpxe/src/util/symcheck.pl new file mode 100755 index 0000000..8925ca6 --- /dev/null +++ b/contrib/syslinux-4.02/gpxe/src/util/symcheck.pl @@ -0,0 +1,191 @@ +#!/usr/bin/perl -w + +use strict; +use warnings; + +use constant WARNING_SIZE => 512; + +my $symtab = {}; + +# Scan output of "objdump -w -t bin/blib.a" and build up symbol table +# +my $object; +while ( <> ) { + chomp; + if ( /^In archive/ ) { + # Do nothing + } elsif ( /^$/ ) { + # Do nothing + } elsif ( /^(\S+\.o):\s+file format/ ) { + $object = $1; + } elsif ( /^SYMBOL TABLE:/ ) { + # Do nothing + } elsif ( /^([0-9a-fA-F]+)\s(l|g|\s)......\s(\S+)\s+([0-9a-fA-F]+)\s+(\S+)$/ ) { + my $value = $1; + my $scope = $2; + my $section = $3; + my $size = $4; + my $symbol = $5; + $symtab->{$object}->{$symbol} = { + global => ( $scope ne "l" ), + section => ( $section eq "*UND*" ? undef : $section ), + value => ( $value ? hex ( $value ) : 0 ), + size => ( $size ? hex ( $size ) : 0 ), + }; + } else { + die "Unrecognized line \"$_\""; + } +} + +# Add symbols that we know will be generated or required by the linker +# +foreach my $object ( keys %$symtab ) { + my $obj_symbol = "obj_$object"; + $obj_symbol =~ s/\.o$//; + $obj_symbol =~ s/\W/_/g; + $symtab->{LINKER}->{$obj_symbol} = { + global => 1, + section => undef, + value => 0, + size => 0, + }; +} +foreach my $link_sym qw ( __prefix _prefix _prefix_load_offset + _prefix_size _prefix_progbits_size _prefix_size_pgh + __text16 _text16 _text16_load_offset + _text16_size _text16_progbits_size _text16_size_pgh + __data16 _data16 _data16_load_offset + _data16_size _data16_progbits_size _data16_size_pgh + __text _text __data _data _textdata_load_offset + _textdata_size _textdata_progbits_size + __rodata __bss _end + _payload_offset _max_align + _load_size _load_size_pgh _load_size_sect + pci_vendor_id pci_device_id ) { + $symtab->{LINKER}->{$link_sym} = { + global => 1, + section => '*ABS*', + value => 0, + size => 0, + }; +} + +# Add symbols that we know will be used by the debug system +# +foreach my $debug_sym qw ( dbg_autocolourise dbg_decolourise + dbg_hex_dump_da ) { + $symtab->{DEBUG}->{$debug_sym} = { + global => 1, + section => undef, + value => 0, + size => 0, + }; +} + +# Build up requires, provides and shares symbol tables for global +# symbols +# +my $globals = {}; +while ( ( my $object, my $symbols ) = each %$symtab ) { + while ( ( my $symbol, my $info ) = each %$symbols ) { + if ( $info->{global} ) { + my $category; + if ( ! defined $info->{section} ) { + $category = "requires"; + } elsif ( $info->{section} eq "*COM*" ) { + $category = "shares"; + } else { + $category = "provides"; + } + $globals->{$symbol}->{$category}->{$object} = 1; + } + } +} + +# Check for multiply defined, never-defined and unused global symbols +# +my $problems = {}; +while ( ( my $symbol, my $info ) = each %$globals ) { + my @provides = keys %{$info->{provides}}; + my @requires = keys %{$info->{requires}}; + my @shares = keys %{$info->{shares}}; + + if ( ( @provides == 0 ) && ( @shares == 1 ) ) { + # A symbol "shared" by just a single file is actually being + # provided by that file; it just doesn't have an initialiser. + @provides = @shares; + @shares = (); + } + + if ( ( @requires > 0 ) && ( @provides == 0 ) && ( @shares == 0 ) ) { + # No object provides this symbol, but some objects require it. + $problems->{$_}->{nonexistent}->{$symbol} = 1 foreach @requires; + } + + if ( ( @requires == 0 ) && ( @provides > 0 ) ) { + # No object requires this symbol, but some objects provide it. + foreach my $provide ( @provides ) { + if ( $provide eq "LINKER" ) { + # Linker-provided symbols are exempt from this check. + } elsif ( $symtab->{$provide}->{$symbol}->{section} =~ /^\.tbl\./ ) { + # Linker tables are exempt from this check. + } else { + $problems->{$provide}->{unused}->{$symbol} = 1; + } + } + } + + if ( ( @shares > 0 ) && ( @provides > 0 ) ) { + # A shared symbol is being initialised by an object + $problems->{$_}->{shared}->{$symbol} = 1 foreach @provides; + } + + if ( @provides > 1 ) { + # A non-shared symbol is defined in multiple objects + $problems->{$_}->{multiples}->{$symbol} = 1 foreach @provides; + } +} + +# Check for excessively large local symbols. Text and rodata symbols +# are exempt from this check +# +while ( ( my $object, my $symbols ) = each %$symtab ) { + while ( ( my $symbol, my $info ) = each %$symbols ) { + if ( ( ! $info->{global} ) && + ( ( defined $info->{section} ) && + ! ( $info->{section} =~ /^(\.text|\.rodata)/ ) ) && + ( $info->{size} >= WARNING_SIZE ) ) { + $problems->{$object}->{large}->{$symbol} = 1; + } + } +} + +# Print out error messages +# +my $errors = 0; +my $warnings = 0; +foreach my $object ( sort keys %$problems ) { + my @nonexistent = sort keys %{$problems->{$object}->{nonexistent}}; + my @multiples = sort keys %{$problems->{$object}->{multiples}}; + my @unused = sort keys %{$problems->{$object}->{unused}}; + my @shared = sort keys %{$problems->{$object}->{shared}}; + my @large = sort keys %{$problems->{$object}->{large}}; + + print "WARN $object provides unused symbol $_\n" foreach @unused; + $warnings += @unused; + print "WARN $object has large static symbol $_\n" foreach @large; + $warnings += @large; + print "ERR $object requires non-existent symbol $_\n" foreach @nonexistent; + $errors += @nonexistent; + foreach my $symbol ( @multiples ) { + my @other_objects = sort grep { $_ ne $object } + keys %{$globals->{$symbol}->{provides}}; + print "ERR $object provides symbol $symbol" + ." (also provided by @other_objects)\n"; + } + $errors += @multiples; + print "ERR $object misuses shared symbol $_\n" foreach @shared; +} + +print "$errors error(s), $warnings warning(s)\n"; +exit ( $errors ? 1 : 0 ); |