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#!/usr/bin/perl -w
# make_sunver.pl
#
# This script takes at least two arguments, a GNU style version script and
# a list of object and archive files, and generates a corresponding Sun
# style version script as follows:
#
# Each glob pattern, C++ mangled pattern or literal in the input script is
# matched against all global symbols in the input objects, emitting those
# that matched (or nothing if no match was found).
# A comment with the original pattern and its type is left in the output
# file to make it easy to understand the matches.
#
# It uses elfdump when present (native), GNU readelf otherwise.
# It depends on the GNU version of c++filt, since it must understand the
# GNU mangling style.
use FileHandle;
use IPC::Open2;
# Enforce C locale.
$ENV{'LC_ALL'} = "C";
$ENV{'LANG'} = "C";
# Input version script, GNU style.
my $symvers = shift;
##########
# Get all the symbols from the library, match them, and add them to a hash.
my %sym_hash = ();
# List of objects and archives to process.
my @OBJECTS = ();
# List of shared objects to omit from processing.
my @SHAREDOBJS = ();
# Filter out those input archives that have corresponding shared objects to
# avoid adding all symbols matched in the archive to the output map.
foreach $file (@ARGV) {
if (($so = $file) =~ s/\.a$/.so/ && -e $so) {
printf STDERR "omitted $file -> $so\n";
push (@SHAREDOBJS, $so);
} else {
push (@OBJECTS, $file);
}
}
# We need to detect and ignore hidden symbols. Solaris nm can only detect
# this in the harder to parse default output format, and GNU nm not at all,
# so use elfdump -s in the native case and GNU readelf -s otherwise.
# GNU objdump -t cannot be used since it produces a variable number of
# columns.
# The path to elfdump.
my $elfdump = "/usr/ccs/bin/elfdump";
if (-f $elfdump) {
open ELFDUMP,$elfdump.' -s '.(join ' ',@OBJECTS).'|' or die $!;
my $skip_arsym = 0;
while (<ELFDUMP>) {
chomp;
# Ignore empty lines.
if (/^$/) {
# End of archive symbol table, stop skipping.
$skip_arsym = 0 if $skip_arsym;
next;
}
# Keep skipping until end of archive symbol table.
next if ($skip_arsym);
# Ignore object name header for individual objects and archives.
next if (/:$/);
# Ignore table header lines.
next if (/^Symbol Table Section:/);
next if (/index.*value.*size/);
# Start of archive symbol table: start skipping.
if (/^Symbol Table: \(archive/) {
$skip_arsym = 1;
next;
}
# Split table.
(undef, undef, undef, undef, $bind, $oth, undef, $shndx, $name) = split;
# Error out for unknown input.
die "unknown input line:\n$_" unless defined($bind);
# Ignore local symbols.
next if ($bind eq "LOCL");
# Ignore hidden symbols.
next if ($oth eq "H");
# Ignore undefined symbols.
next if ($shndx eq "UNDEF");
# Error out for unhandled cases.
if ($bind !~ /^(GLOB|WEAK)/ or $oth ne "D") {
die "unhandled symbol:\n$_";
}
# Remember symbol.
$sym_hash{$name}++;
}
close ELFDUMP or die "$elfdump error";
} else {
open READELF, 'readelf -s -W '.(join ' ',@OBJECTS).'|' or die $!;
# Process each symbol.
while (<READELF>) {
chomp;
# Ignore empty lines.
next if (/^$/);
# Ignore object name header.
next if (/^File: .*$/);
# Ignore table header lines.
next if (/^Symbol table.*contains.*:/);
next if (/Num:.*Value.*Size/);
# Split table.
(undef, undef, undef, undef, $bind, $vis, $ndx, $name) = split;
# Error out for unknown input.
die "unknown input line:\n$_" unless defined($bind);
# Ignore local symbols.
next if ($bind eq "LOCAL");
# Ignore hidden symbols.
next if ($vis eq "HIDDEN");
# Ignore undefined symbols.
next if ($ndx eq "UND");
# Error out for unhandled cases.
if ($bind !~ /^(GLOBAL|WEAK)/ or $vis ne "DEFAULT") {
die "unhandled symbol:\n$_";
}
# Remember symbol.
$sym_hash{$name}++;
}
close READELF or die "readelf error";
}
##########
# The various types of glob patterns.
#
# A glob pattern that is to be applied to the demangled name: 'cxx'.
# A glob patterns that applies directly to the name in the .o files: 'glob'.
# This pattern is ignored; used for local variables (usually just '*'): 'ign'.
# The type of the current pattern.
my $glob = 'glob';
# We're currently inside `extern "C++"', which Sun ld doesn't understand.
my $in_extern = 0;
# The c++filt command to use. This *must* be GNU c++filt; the Sun Studio
# c++filt doesn't handle the GNU mangling style.
my $cxxfilt = $ENV{'CXXFILT'} || "c++filt";
# The current version name.
my $current_version = "";
# Was there any attempt to match a symbol to this version?
my $matches_attempted;
# The number of versions which matched this symbol.
my $matched_symbols;
open F,$symvers or die $!;
# Print information about generating this file
print "# This file was generated by make_sunver.pl. DO NOT EDIT!\n";
print "# It was generated by:\n";
printf "# %s %s %s\n", $0, $symvers, (join ' ',@ARGV);
printf "# Omitted archives with corresponding shared libraries: %s\n",
(join ' ', @SHAREDOBJS) if $#SHAREDOBJS >= 0;
print "#\n\n";
while (<F>) {
# Lines of the form '};'
if (/^([ \t]*)(\}[ \t]*;[ \t]*)$/) {
$glob = 'glob';
if ($in_extern) {
$in_extern--;
print "$1##$2\n";
} else {
print;
}
next;
}
# Lines of the form '} SOME_VERSION_NAME_1.0;'
if (/^[ \t]*\}[ \tA-Z0-9_.a-z]+;[ \t]*$/) {
$glob = 'glob';
# We tried to match symbols agains this version, but none matched.
# Emit dummy hidden symbol to avoid marking this version WEAK.
if ($matches_attempted && $matched_symbols == 0) {
print " hidden:\n";
print " .force_WEAK_off_$current_version = DATA S0x0 V0x0;\n";
}
print; next;
}
# Comment and blank lines
if (/^[ \t]*\#/) { print; next; }
if (/^[ \t]*$/) { print; next; }
# Lines of the form '{'
if (/^([ \t]*){$/) {
if ($in_extern) {
print "$1##{\n";
} else {
print;
}
next;
}
# Lines of the form 'SOME_VERSION_NAME_1.1 {'
if (/^([A-Z0-9_.]+)[ \t]+{$/) {
# Record version name.
$current_version = $1;
# Reset match attempts, #matched symbols for this version.
$matches_attempted = 0;
$matched_symbols = 0;
print;
next;
}
# Ignore 'global:'
if (/^[ \t]*global:$/) { print; next; }
# After 'local:', globs should be ignored, they won't be exported.
if (/^[ \t]*local:$/) {
$glob = 'ign';
print;
next;
}
# After 'extern "C++"', globs are C++ patterns
if (/^([ \t]*)(extern \"C\+\+\"[ \t]*)$/) {
$in_extern++;
$glob = 'cxx';
# Need to comment, Sun ld cannot handle this.
print "$1##$2\n"; next;
}
# Chomp newline now we're done with passing through the input file.
chomp;
# Catch globs. Note that '{}' is not allowed in globs by this script,
# so only '*' and '[]' are available.
if (/^([ \t]*)([^ \t;{}#]+);?[ \t]*$/) {
my $ws = $1;
my $ptn = $2;
# Turn the glob into a regex by replacing '*' with '.*', '?' with '.'.
# Keep $ptn so we can still print the original form.
($pattern = $ptn) =~ s/\*/\.\*/g;
$pattern =~ s/\?/\./g;
if ($glob eq 'ign') {
# We're in a local: * section; just continue.
print "$_\n";
next;
}
# Print the glob commented for human readers.
print "$ws##$ptn ($glob)\n";
# We tried to match a symbol to this version.
$matches_attempted++;
if ($glob eq 'glob') {
my %ptn_syms = ();
# Match ptn against symbols in %sym_hash.
foreach my $sym (keys %sym_hash) {
# Maybe it matches one of the patterns based on the symbol in
# the .o file.
$ptn_syms{$sym}++ if ($sym =~ /^$pattern$/);
}
foreach my $sym (sort keys(%ptn_syms)) {
$matched_symbols++;
print "$ws$sym;\n";
}
} elsif ($glob eq 'cxx') {
my %dem_syms = ();
# Verify that we're actually using GNU c++filt. Other versions
# most likely cannot handle GNU style symbol mangling.
my $cxxout = `$cxxfilt --version 2>&1`;
$cxxout =~ m/GNU/ or die "$0 requires GNU c++filt to function";
# Talk to c++filt through a pair of file descriptors.
# Need to start a fresh instance per pattern, otherwise the
# process grows to 500+ MB.
my $pid = open2(*FILTIN, *FILTOUT, $cxxfilt) or die $!;
# Match ptn against symbols in %sym_hash.
foreach my $sym (keys %sym_hash) {
# No? Well, maybe its demangled form matches one of those
# patterns.
printf FILTOUT "%s\n",$sym;
my $dem = <FILTIN>;
chomp $dem;
$dem_syms{$sym}++ if ($dem =~ /^$pattern$/);
}
close FILTOUT or die "c++filt error";
close FILTIN or die "c++filt error";
# Need to wait for the c++filt process to avoid lots of zombies.
waitpid $pid, 0;
foreach my $sym (sort keys(%dem_syms)) {
$matched_symbols++;
print "$ws$sym;\n";
}
} else {
# No? Well, then ignore it.
}
next;
}
# Important sanity check. This script can't handle lots of formats
# that GNU ld can, so be sure to error out if one is seen!
die "strange line `$_'";
}
close F;