/security/nss/lib/freebl/mpi/types.pl
http://github.com/zpao/v8monkey · Perl · 162 lines · 76 code · 25 blank · 61 comment · 7 complexity · 95dd3e4fdfbb4e70ad72940af2a9527b MD5 · raw file
- #!/usr/bin/perl
- #
- # types.pl - find recommended type definitions for digits and words
- #
- # This script scans the Makefile for the C compiler and compilation
- # flags currently in use, and using this combination, attempts to
- # compile a simple test program that outputs the sizes of the various
- # unsigned integer types, in bytes. Armed with these, it finds all
- # the "viable" type combinations for mp_digit and mp_word, where
- # viability is defined by the requirement that mp_word be at least two
- # times the precision of mp_digit.
- #
- # Of these, the one with the largest digit size is chosen, and
- # appropriate typedef statements are written to standard output.
- # ***** BEGIN LICENSE BLOCK *****
- # Version: MPL 1.1/GPL 2.0/LGPL 2.1
- #
- # The contents of this file are subject to the Mozilla Public License Version
- # 1.1 (the "License"); you may not use this file except in compliance with
- # the License. You may obtain a copy of the License at
- # http://www.mozilla.org/MPL/
- #
- # Software distributed under the License is distributed on an "AS IS" basis,
- # WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- # for the specific language governing rights and limitations under the
- # License.
- #
- # The Original Code is the MPI Arbitrary Precision Integer Arithmetic library.
- #
- # The Initial Developer of the Original Code is
- # Michael J. Fromberger <sting@linguist.dartmouth.edu>.
- # Portions created by the Initial Developer are Copyright (C) 2000
- # the Initial Developer. All Rights Reserved.
- #
- # Contributor(s):
- #
- # Alternatively, the contents of this file may be used under the terms of
- # either the GNU General Public License Version 2 or later (the "GPL"), or
- # the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- # in which case the provisions of the GPL or the LGPL are applicable instead
- # of those above. If you wish to allow use of your version of this file only
- # under the terms of either the GPL or the LGPL, and not to allow others to
- # use your version of this file under the terms of the MPL, indicate your
- # decision by deleting the provisions above and replace them with the notice
- # and other provisions required by the GPL or the LGPL. If you do not delete
- # the provisions above, a recipient may use your version of this file under
- # the terms of any one of the MPL, the GPL or the LGPL.
- #
- # ***** END LICENSE BLOCK *****
- # $Id: types.pl,v 1.2 2005/02/02 22:28:22 gerv%gerv.net Exp $
- #
- @_=split(/\//,$0);chomp($prog=pop(@_));
- # The array of integer types to be considered...
- @TYPES = (
- "unsigned char",
- "unsigned short",
- "unsigned int",
- "unsigned long"
- );
- # Macro names for the maximum unsigned value of each type
- %TMAX = (
- "unsigned char" => "UCHAR_MAX",
- "unsigned short" => "USHRT_MAX",
- "unsigned int" => "UINT_MAX",
- "unsigned long" => "ULONG_MAX"
- );
- # Read the Makefile to find out which C compiler to use
- open(MFP, "<Makefile") or die "$prog: Makefile: $!\n";
- while(<MFP>) {
- chomp;
- if(/^CC=(.*)$/) {
- $cc = $1;
- last if $cflags;
- } elsif(/^CFLAGS=(.*)$/) {
- $cflags = $1;
- last if $cc;
- }
- }
- close(MFP);
- # If we couldn't find that, use 'cc' by default
- $cc = "cc" unless $cc;
- printf STDERR "Using '%s' as the C compiler.\n", $cc;
- print STDERR "Determining type sizes ... \n";
- open(OFP, ">tc$$.c") or die "$prog: tc$$.c: $!\n";
- print OFP "#include <stdio.h>\n\nint main(void)\n{\n";
- foreach $type (@TYPES) {
- printf OFP "\tprintf(\"%%d\\n\", (int)sizeof(%s));\n", $type;
- }
- print OFP "\n\treturn 0;\n}\n";
- close(OFP);
- system("$cc $cflags -o tc$$ tc$$.c");
- die "$prog: unable to build test program\n" unless(-x "tc$$");
- open(IFP, "./tc$$|") or die "$prog: can't execute test program\n";
- $ix = 0;
- while(<IFP>) {
- chomp;
- $size{$TYPES[$ix++]} = $_;
- }
- close(IFP);
- unlink("tc$$");
- unlink("tc$$.c");
- print STDERR "Selecting viable combinations ... \n";
- while(($type, $size) = each(%size)) {
- push(@ts, [ $size, $type ]);
- }
- # Sort them ascending by size
- @ts = sort { $a->[0] <=> $b->[0] } @ts;
- # Try all possible combinations, finding pairs in which the word size
- # is twice the digit size. The number of possible pairs is too small
- # to bother doing this more efficiently than by brute force
- for($ix = 0; $ix <= $#ts; $ix++) {
- $w = $ts[$ix];
- for($jx = 0; $jx <= $#ts; $jx++) {
- $d = $ts[$jx];
- if($w->[0] == 2 * $d->[0]) {
- push(@valid, [ $d, $w ]);
- }
- }
- }
- # Sort descending by digit size
- @valid = sort { $b->[0]->[0] <=> $a->[0]->[0] } @valid;
- # Select the maximum as the recommended combination
- $rec = shift(@valid);
- printf("typedef %-18s mp_sign;\n", "char");
- printf("typedef %-18s mp_digit; /* %d byte type */\n",
- $rec->[0]->[1], $rec->[0]->[0]);
- printf("typedef %-18s mp_word; /* %d byte type */\n",
- $rec->[1]->[1], $rec->[1]->[0]);
- printf("typedef %-18s mp_size;\n", "unsigned int");
- printf("typedef %-18s mp_err;\n\n", "int");
- printf("#define %-18s (CHAR_BIT*sizeof(mp_digit))\n", "DIGIT_BIT");
- printf("#define %-18s %s\n", "DIGIT_MAX", $TMAX{$rec->[0]->[1]});
- printf("#define %-18s (CHAR_BIT*sizeof(mp_word))\n", "MP_WORD_BIT");
- printf("#define %-18s %s\n\n", "MP_WORD_MAX", $TMAX{$rec->[1]->[1]});
- printf("#define %-18s (DIGIT_MAX+1)\n\n", "RADIX");
- printf("#define %-18s \"%%0%dX\"\n", "DIGIT_FMT", (2 * $rec->[0]->[0]));
- exit 0;