#!/usr/bin/perl
## --------------------------------------------------------------------------
##
## Copyright 1996-2017 The NASM Authors - All Rights Reserved
## See the file AUTHORS included with the NASM distribution for
## the specific copyright holders.
##
## Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following
## conditions are met:
##
## * Redistributions of source code must retain the above copyright
## notice, this list of conditions and the following disclaimer.
## * Redistributions in binary form must reproduce the above
## copyright notice, this list of conditions and the following
## disclaimer in the documentation and/or other materials provided
## with the distribution.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
## CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
## INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
## MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
## DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
## CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
## NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
## LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
## HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
## CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
## OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
## EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
##
## --------------------------------------------------------------------------
#
# Generate a perfect hash for general case-insensitive string-to-enum
# lookup. This generates an enum and the corresponding hash, but
# relies on a common function to parse the hash.
#
# Usage:
# perfhash.pl h foohash.dat foohash.h (to generate C header)
# perfhash.pl c foohash.dat foohash.c (to generate C source)
#
use strict;
require 'phash.ph';
sub basename($) {
my($s) = @_;
$s =~ s/^.*[^-[:alnum:]_\.]//; # Remove path component as best we can
return $s;
}
sub intval($) {
my($s) = @_;
if ($s =~ /^0/) {
return oct($s); # Handles octal or hexadecimal
} elsif ($s =~ /^\-(0.*)$/) {
return -oct($1);
} else {
return $s + 0; # Forcibly convert to number
}
}
my($output, $infile, $outfile) = @ARGV;
my $me = basename($0);
# The following special things are allowed in the input file:
# #<space> or ; begins a comment
# #include filename
# #name str
# The name of the hash
# #prefix str
# Defines the prefix before enum
# #guard str
# Defines the header guard string
# #special str [= value]
# Generate an enum value without a corresponding string; not capitalized.
# #header str
# Indicates the name of the .h file to include from the .c file
# #errval str
# Define the value to be returned if a string is not found
# (defaults to -1). This can be any constant C expression,
# including one of the enum values.
#
# Regular lines are just str [= value]
#
# Enumeration is generated in the order listed in the file, just as in C
# specifying a value causes the values to increase by 1 from that point on
# unless specified.
my $name;
my $prefix;
my $guard;
my $hfile;
my %strings = ();
my %specials = ();
my $next_value = 0;
my $errval = '-1';
my @incstack = ();
my @filenames = ($infile);
my @linenums = (0);
my $dd = undef;
my $err = 0;
while (scalar(@filenames)) {
if (!defined($dd)) {
open($dd, '<', $filenames[-1])
or die "$0: cannot open: $filenames[-1]: $!\n";
}
my $line = <$dd>;
if (!defined($line)) {
close($dd);
$dd = pop @incstack;
pop @filenames;
pop @linenums;
next;
}
$linenums[-1]++;
chomp $line;
$line =~ s/\s*(|\;.*|\#\s.*|\#)$//; # Remove comments and trailing space
$line =~ s/^\s+//; # Remove leading space
if ($line eq '') {
# Do nothing
} elsif ($line =~ /^\#name\s+([[:alnum:]_]+)$/) {
$name = $1;
} elsif ($line =~ /^\#prefix\s+([[:alnum:]_]+)$/) {
$prefix = $1;
} elsif ($line =~ /^\#guard\s+([[:alnum:]_]+)$/) {
$guard = $1;
} elsif ($line =~ /^\#errval\s+(\S.*)$/) {
$errval = $1;
} elsif ($line =~ /^\#header\s+(\"(.+)\"|\S+)$/) {
$hfile = ($2 ne '') ? $2 : $1;
} elsif ($line =~ /^\#include\s+(\"(.+)\"|\S+)$/) {
push @incstack, $dd;
push @filenames, (($2 ne '') ? $2 : $1);
push @linenums, 0;
undef $dd; # Open a new file
} elsif ($line =~ /^(|\#special\s+)(\S+)\s*(|=\s*(\-?(0[Xx][[:xdigit:]]+|0[0-7]*|[0-9]+)))$/) {
$next_value = intval($4) if ($4 ne '');
if ($1 eq '') {
$strings{$2} = $next_value++;
} else {
$specials{$2} = $next_value++;
}
} else {
printf STDERR "%s:%d:%s syntax error: \"%s\"\n",
$filenames[-1], $linenums[-1],
(scalar(@incstack) == 1) ? '' : "(from $infile)", $line;
$err++;
}
}
exit 1 if ($err);
# Default name, prefix, and header guard name
if (!defined($name)) {
$name = basename($infile);
$name =~ s/(\..*)$//; # Strip extension, if any
}
if (!defined($prefix)) {
$prefix = "\U${name}\E_";
}
if (!defined($hfile)) {
$hfile = $outfile;
$hfile =~ s/\.c$/\.h/;
}
if (!defined($guard)) {
$guard = basename($hfile);
$guard =~ s/[^[:alnum:]_]/_/g;
$guard =~ s/__+/_/g;
$guard = "\U$guard";
}
# Verify input. We can't have more than one constant with the same
# enumeration value, nor the same enumeration string.
if (scalar(keys(%strings)) == 0) {
die "$0: $infile: no strings to hash!\n";
}
my %enums;
my %enumvals;
my %stringbyval;
my $max_enum;
my $tbllen = 0;
my $tbloffs;
foreach my $s (keys(%strings)) {
my $es = "${prefix}\U${s}";
$es =~ s/[^[:alnum:]_]/_/g;
$es =~ s/__+/_/g;
my $v = $strings{$s};
$stringbyval{$v} = $s;
if (defined($enums{$es})) {
printf STDERR "%s: string \"%s\" duplicates existing enum %s\n",
$infile, $s, $es;
$err++;
} else {
$enums{$es} = $v;
}
if (defined($enumvals{$v})) {
printf STDERR "%s: string \"%s\" duplicates existing enum constant %d\n", $v;
$err++;
} else {
$enumvals{$v} = $es;
}
$max_enum = $v if ($v > $max_enum || !defined($max_enum));
$tbloffs = $v if ($v < $tbloffs || !defined($tbloffs));
$tbllen = $v+1 if ($v >= $tbllen || !defined($tbllen));
}
foreach my $s (keys(%specials)) {
my $es = $prefix . $s; # No string mangling here
my $v = $specials{$s};
if (defined($enums{$es})) {
printf STDERR "%s: special \"%s\" duplicates existing enum %s\n",
$infile, $s, $es;
$err++;
} else {
$enums{$es} = $v;
}
if (defined ($enumvals{$v})) {
printf STDERR "%s: special \"%s\" duplicates existing enum constant %d\n", $v;
$err++;
} else {
$enumvals{$v} = $es;
}
$max_enum = $v if ($v > $max_enum || !defined($max_enum));
}
$tbllen -= $tbloffs;
if ($tbllen > 65536) {
printf STDERR "%s: span of enumeration values too large\n";
$err++;
}
exit 1 if ($err);
open(F, '>', $outfile)
or die "$0: cannot create: ${outfile}: $!\n";
if ($output eq 'h') {
print F "/*\n";
print F " * This file is generated from $infile\n";
print F " * by $me; do not edit.\n";
print F " */\n";
print F "\n";
print F "#ifndef $guard\n";
print F "#define $guard 1\n\n";
print F "#include \"perfhash.h\"\n\n";
my $c = '{';
$next_value = 0;
print F "enum ${name} ";
foreach my $v (sort { $a <=> $b } keys(%enumvals)) {
my $s = $enumvals{$v};
print F "$c\n $s";
print F " = $v" if ($v != $next_value);
$next_value = $v + 1;
$c = ',';
}
print F "\n};\n\n";
print F "extern const struct perfect_hash ${name}_hash;\n";
printf F "extern const char * const %s_tbl[%d];\n", $name, $tbllen;
print F "\nstatic inline enum ${name} ${name}_find(const char *str)\n";
print F "{\n";
print F " return perfhash_find(&${name}_hash, str);\n";
print F "}\n";
print F "\nstatic inline const char * ${name}_name(enum ${name} x)\n";
print F "{\n";
printf F " size_t ix = (size_t)x - (%d);\n", $tbloffs;
printf F " if (ix >= %d)\n", $tbllen;
print F " return NULL;\n";
print F " return ${name}_tbl[ix];\n";
print F "}\n";
print F "\nstatic inline const char * ${name}_dname(enum ${name} x)\n";
print F "{\n";
print F " const char *y = ${name}_name(x);\n";
print F " return y ? y : invalid_enum_str(x);\n";
print F "}\n";
print F "\n#endif /* $guard */\n";
} elsif ($output eq 'c') {
# The strings we hash must all be lower case, even if the string
# table doesn't contain them that way.
my %lcstrings;
foreach my $s (keys(%strings)) {
my $ls = "\L$s";
if (defined($lcstrings{$ls})) {
printf STDERR "%s: strings \"%s\" and \"%s\" differ only in case\n",
$infile, $s, $strings{$lcstrings{$s}};
} else {
$lcstrings{$ls} = $strings{$s} - $tbloffs;
}
}
my @hashinfo = gen_perfect_hash(\%lcstrings);
if (!@hashinfo) {
die "$0: no hash found\n";
}
# Paranoia...
verify_hash_table(\%lcstrings, \@hashinfo);
my ($n, $sv, $g) = @hashinfo;
die if ($n & ($n-1));
print F "/*\n";
print F " * This file is generated from $infile\n";
print F " * by $me; do not edit.\n";
print F " */\n";
print F "\n";
print F "#include \"$hfile\"\n\n";
printf F "const char * const %s_tbl[%d] = ", $name, $tbllen;
my $c = '{';
for (my $i = $tbloffs; $i < $tbloffs+$tbllen; $i++) {
printf F "%s\n %s", $c,
defined($stringbyval{$i}) ? '"'.$stringbyval{$i}.'"' : 'NULL';
$c = ',';
}
print F "\n};\n\n";
print F "#define UNUSED (65536/3)\n\n";
printf F "static const int16_t %s_hashvals[%d] = ", $name, $n*2;
$c = '{';
for (my $i = 0; $i < $n; $i++) {
my $h = ${$g}[$i*2+0];
print F "$c\n ", defined($h) ? $h : 'UNUSED';
$c = ',';
}
for (my $i = 0; $i < $n; $i++) {
my $h = ${$g}[$i*2+1];
print F "$c\n ", defined($h) ? $h : 'UNUSED';
$c = ',';
}
print F "\n};\n\n";
print F "const struct perfect_hash ${name}_hash = {\n";
printf F " UINT64_C(0x%08x%08x),\n", $$sv[0], $$sv[1]; # crcinit
printf F " UINT32_C(0x%x),\n", $n-1; # hashmask
printf F " UINT32_C(%u),\n", $tbllen; # tbllen
printf F " %d,\n", $tbloffs; # tbloffs
printf F " (%s),\n", $errval; # errval
printf F " ${name}_hashvals,\n"; # hashvals
printf F " ${name}_tbl\n"; # strings
print F "};\n";
}