3 # Generate query_config.c
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.
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.
17 # Usage: ./scripts/generate_query_config.pl without arguments
21 my $config_file = "./include/mbedtls/config.h";
23 my $query_config_format_file = "./scripts/data_files/query_config.fmt";
24 my $query_config_file = "./programs/ssl/query_config.c";
26 # Excluded macros from the generated query_config.c. For example, macros that
27 # have commas or function-like macros cannot be transformed into strings easily
28 # using the preprocessor, so they should be excluded or the preprocessor will
31 MBEDTLS_SSL_CIPHERSUITES
34 my $excluded_re = join '|', @excluded;
36 open(CONFIG_FILE, "$config_file") or die "Opening config file '$config_file': $!";
38 # This variable will contain the string to replace in the CHECK_CONFIG of the
40 my $config_check = "";
42 while (my $line = <CONFIG_FILE>) {
43 if ($line =~ /^(\/\/)?\s*#\s*define\s+(MBEDTLS_\w+).*/) {
46 # Skip over the macro that prevents multiple inclusion
47 next if "MBEDTLS_CONFIG_H" eq $name;
49 # Skip over the macro if it is in the ecluded list
50 next if $name =~ /$excluded_re/;
52 $config_check .= "#if defined($name)\n";
53 $config_check .= " if( strcmp( \"$name\", config ) == 0 )\n";
54 $config_check .= " {\n";
55 $config_check .= " MACRO_EXPANSION_TO_STR( $name );\n";
56 $config_check .= " return( 0 );\n";
57 $config_check .= " }\n";
58 $config_check .= "#endif /* $name */\n";
59 $config_check .= "\n";
63 # Read the full format file into a string
65 open(FORMAT_FILE, "$query_config_format_file") or die "Opening query config format file '$query_config_format_file': $!";
66 my $query_config_format = <FORMAT_FILE>;
69 # Replace the body of the query_config() function with the code we just wrote
70 $query_config_format =~ s/CHECK_CONFIG/$config_check/g;
72 # Rewrite the query_config.c file
73 open(QUERY_CONFIG_FILE, ">$query_config_file") or die "Opening destination file '$query_config_file': $!";
74 print QUERY_CONFIG_FILE $query_config_format;
75 close(QUERY_CONFIG_FILE);