1#! /usr/bin/env perl 2 3# Generate query_config.c 4# 5# The file query_config.c contains a C function that can be used to check if 6# a configuration macro is defined and to retrieve its expansion in string 7# form (if any). This facilitates querying the compile time configuration of 8# the library, for example, for testing. 9# 10# The query_config.c is generated from the current configuration at 11# include/mbedtls/config.h. The idea is that the config.h contains ALL the 12# compile time configurations available in Mbed TLS (commented or uncommented). 13# This script extracts the configuration macros from the config.h and this 14# information is used to automatically generate the body of the query_config() 15# function by using the template in scripts/data_files/query_config.fmt. 16# 17# Usage: ./scripts/generate_query_config.pl without arguments 18# 19# Copyright The Mbed TLS Contributors 20# SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 21 22use strict; 23 24my $config_file = "./include/mbedtls/config.h"; 25 26my $query_config_format_file = "./scripts/data_files/query_config.fmt"; 27my $query_config_file = "./programs/test/query_config.c"; 28 29# Excluded macros from the generated query_config.c. For example, macros that 30# have commas or function-like macros cannot be transformed into strings easily 31# using the preprocessor, so they should be excluded or the preprocessor will 32# throw errors. 33my @excluded = qw( 34MBEDTLS_SSL_CIPHERSUITES 35MBEDTLS_PARAM_FAILED 36); 37my $excluded_re = join '|', @excluded; 38 39open(CONFIG_FILE, "$config_file") or die "Opening config file '$config_file': $!"; 40 41# This variable will contain the string to replace in the CHECK_CONFIG of the 42# format file 43my $config_check = ""; 44my $list_config = ""; 45 46while (my $line = <CONFIG_FILE>) { 47 if ($line =~ /^(\/\/)?\s*#\s*define\s+(MBEDTLS_\w+).*/) { 48 my $name = $2; 49 50 # Skip over the macro that prevents multiple inclusion 51 next if "MBEDTLS_CONFIG_H" eq $name; 52 53 # Skip over the macro if it is in the ecluded list 54 next if $name =~ /$excluded_re/; 55 56 $config_check .= "#if defined($name)\n"; 57 $config_check .= " if( strcmp( \"$name\", config ) == 0 )\n"; 58 $config_check .= " {\n"; 59 $config_check .= " MACRO_EXPANSION_TO_STR( $name );\n"; 60 $config_check .= " return( 0 );\n"; 61 $config_check .= " }\n"; 62 $config_check .= "#endif /* $name */\n"; 63 $config_check .= "\n"; 64 65 $list_config .= "#if defined($name)\n"; 66 $list_config .= " OUTPUT_MACRO_NAME_VALUE($name);\n"; 67 $list_config .= "#endif /* $name */\n"; 68 $list_config .= "\n"; 69 } 70} 71 72# Read the full format file into a string 73local $/; 74open(FORMAT_FILE, "$query_config_format_file") or die "Opening query config format file '$query_config_format_file': $!"; 75my $query_config_format = <FORMAT_FILE>; 76close(FORMAT_FILE); 77 78# Replace the body of the query_config() function with the code we just wrote 79$query_config_format =~ s/CHECK_CONFIG/$config_check/g; 80$query_config_format =~ s/LIST_CONFIG/$list_config/g; 81 82# Rewrite the query_config.c file 83open(QUERY_CONFIG_FILE, ">$query_config_file") or die "Opening destination file '$query_config_file': $!"; 84print QUERY_CONFIG_FILE $query_config_format; 85close(QUERY_CONFIG_FILE); 86