scripts/singleuse: script to use to track single-use functions

#!/usr/bin/perl

#***************************************************************************

#                                  _   _ ____  _

#  Project                     ___| | | |  _ \| |

#                             / __| | | | |_) | |

#                            | (__| |_| |  _ <| |___

#                             \___|\___/|_| \_\_____|

#

# Copyright (C) 2019, Daniel Stenberg, <daniel@haxx.se>, et al.

#

# This software is licensed as described in the file COPYING, which

# you should have received as part of this distribution. The terms

# are also available at https://curl.haxx.se/docs/copyright.html.

#

# You may opt to use, copy, modify, merge, publish, distribute and/or sell

# copies of the Software, and permit persons to whom the Software is

# furnished to do so, under the terms of the COPYING file.

#

# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY

# KIND, either express or implied.

#

###########################################################################

#

# This script is aimed to help scan for and detect globally declared functions

# that are not used from other source files.

#

# Use it like this:

#

# $ ./scripts/singleuse.pl lib/.libs/libcurl.a

#

# Be aware that it might cause false positives due to various build options.

#

my $file = $ARGV[0];

my %wl = (

    'Curl_none_cert_status_request' => 'multiple TLS backends',

    'Curl_none_check_cxn' => 'multiple TLS backends',

    'Curl_none_cleanup' => 'multiple TLS backends',

    'Curl_none_close_all' => 'multiple TLS backends',

    'Curl_none_data_pending' => 'multiple TLS backends',

    'Curl_none_engines_list' => 'multiple TLS backends',

    'Curl_none_init' => 'multiple TLS backends',

    'Curl_none_md5sum' => 'multiple TLS backends',

    'Curl_none_random' => 'multiple TLS backends',

    'Curl_none_session_free' => 'multiple TLS backends',

    'Curl_none_set_engine' => 'multiple TLS backends',

    'Curl_none_set_engine_default' => 'multiple TLS backends',

    'Curl_none_shutdown' => 'multiple TLS backends',

    'Curl_multi_dump' => 'debug build only',

    'Curl_parse_port' => 'UNITTEST',

    'Curl_shuffle_addr' => 'UNITTEST',

    'de_cleanup' => 'UNITTEST',

    'doh_decode' => 'UNITTEST',

    'doh_encode' => 'UNITTEST',

    'Curl_auth_digest_get_pair' => 'by digest_sspi',

    'curlx_uztoso' => 'cmdline tool use',

    'curlx_uztoul' => 'by krb5_sspi',

    'curlx_uitous' => 'by schannel',

    'Curl_islower' => 'by curl_fnmatch',

    'getaddressinfo' => 'UNITTEST',

    );

my %api = (

    'curl_easy_cleanup' => 'API',

    'curl_easy_duphandle' => 'API',

    'curl_easy_escape' => 'API',

    'curl_easy_getinfo' => 'API',

    'curl_easy_init' => 'API',

    'curl_easy_pause' => 'API',

    'curl_easy_perform' => 'API',

    'curl_easy_recv' => 'API',

    'curl_easy_reset' => 'API',

    'curl_easy_send' => 'API',

    'curl_easy_setopt' => 'API',

    'curl_easy_strerror' => 'API',

    'curl_easy_unescape' => 'API',

    'curl_easy_upkeep' => 'API',

    'curl_escape' => 'API',

    'curl_formadd' => 'API',

    'curl_formfree' => 'API',

    'curl_formget' => 'API',

    'curl_free' => 'API',

    'curl_getdate' => 'API',

    'curl_getenv' => 'API',

    'curl_global_cleanup' => 'API',

    'curl_global_init' => 'API',

    'curl_global_init_mem' => 'API',

    'curl_global_sslset' => 'API',

    'curl_maprintf' => 'API',

    'curl_mfprintf' => 'API',

    'curl_mime_addpart' => 'API',

    'curl_mime_data' => 'API',

    'curl_mime_data_cb' => 'API',

    'curl_mime_encoder' => 'API',

    'curl_mime_filedata' => 'API',

    'curl_mime_filename' => 'API',

    'curl_mime_free' => 'API',

    'curl_mime_headers' => 'API',

    'curl_mime_init' => 'API',

    'curl_mime_name' => 'API',

    'curl_mime_subparts' => 'API',

    'curl_mime_type' => 'API',

    'curl_mprintf' => 'API',

    'curl_msnprintf' => 'API',

    'curl_msprintf' => 'API',

    'curl_multi_add_handle' => 'API',

    'curl_multi_assign' => 'API',

    'curl_multi_cleanup' => 'API',

    'curl_multi_fdset' => 'API',

    'curl_multi_info_read' => 'API',

    'curl_multi_init' => 'API',

    'curl_multi_perform' => 'API',

    'curl_multi_remove_handle' => 'API',

    'curl_multi_setopt' => 'API',

    'curl_multi_socket' => 'API',

    'curl_multi_socket_action' => 'API',

    'curl_multi_socket_all' => 'API',

    'curl_multi_strerror' => 'API',

    'curl_multi_timeout' => 'API',

    'curl_multi_wait' => 'API',

    'curl_mvaprintf' => 'API',

    'curl_mvfprintf' => 'API',

    'curl_mvprintf' => 'API',

    'curl_mvsnprintf' => 'API',

    'curl_mvsprintf' => 'API',

    'curl_pushheader_byname' => 'API',

    'curl_pushheader_bynum' => 'API',

    'curl_share_cleanup' => 'API',

    'curl_share_init' => 'API',

    'curl_share_setopt' => 'API',

    'curl_share_strerror' => 'API',

    'curl_slist_append' => 'API',

    'curl_slist_free_all' => 'API',

    'curl_strequal' => 'API',

    'curl_strnequal' => 'API',

    'curl_unescape' => 'API',

    'curl_url' => 'API',

    'curl_url_cleanup' => 'API',

    'curl_url_dup' => 'API',

    'curl_url_get' => 'API',

    'curl_url_set' => 'API',

    'curl_version' => 'API',

    'curl_version_info' => 'API',

    # the following funcions are provided globally in debug builds

    'curl_easy_perform_ev' => 'debug-build',

    'curl_memdebug' => 'debug-build',

    'curl_memlimit' => 'debug-build',

    'curl_memlog' => 'debug-build',

    'curl_accept' => 'debug-build',

    'curl_docalloc' => 'debug-build',

    'curl_dofree' => 'debug-build',

    'curl_domalloc' => 'debug-build',

    'curl_dorealloc' => 'debug-build',

    'curl_dorecv' => 'debug-build',

    'curl_dosend' => 'debug-build',

    'curl_dostrdup' => 'debug-build',

    'curl_fclose' => 'debug-build',

    'curl_fopen' => 'debug-build',

    'curl_sclose' => 'debug-build',

    'curl_socket' => 'debug-build',

    'curl_socketpair' => 'debug-build',

    );

open(N, "nm $file|") ||

    die;

my %exist;

my %uses;

my $file;

while (<N>) {

    my $l = $_;

    chomp $l;

    if($l =~ /^([0-9a-z_-]+)\.o:/) {

        $file = $1;

    }

    if($l =~ /^([0-9a-f]+) T (.*)/) {

        my ($name)=($2);

        #print "Define $name in $file\n";

        $file =~ s/^libcurl_la-//;

        $exist{$name} = $file;

    }

    elsif($l =~ /^                 U (.*)/) {

        my ($name)=($1);

        #print "Uses $name in $file\n";

        $uses{$name} .= "$file, ";

    }

}

close(N);

my $err;

for(sort keys %exist) {

    #printf "%s is defined in %s, used by: %s\n", $_, $exist{$_}, $uses{$_};

    if(!$uses{$_}) {

        # this is a symbol with no "global" user

        if($_ =~ /^curl_/) {

            if(!$api{$_}) {

                # not present in the API, or for debug-builds

                print STDERR "Bad curl-prefix: $_\n";

                $err++;

            }

        }

        elsif($wl{$_}) {

            #print "$_ is WL\n";

        }

        else {

            printf "%s is defined in %s, but not used outside\n", $_, $exist{$_};

            $err++;

        }

    }

    elsif($_ =~ /^curl_/) {

        # global prefix, make sure it is "blessed"

        if(!$api{$_}) {

            # not present in the API, or for debug-builds

            print STDERR "Bad curl-prefix $_\n";

            $err++;

        }

    }

}

exit $err;