simpleidlpp

: # -*- perl -*-
eval 'exec perl -w -S $0 "$@"'
if 0;

# please keep in sync with keyrefpp

require 5.10.0;

use strict;
use Carp;
use Getopt::Std;

my %opts;
getopts ("hr", \%opts);

if (exists ${opts{h}} || @ARGV == 0) {
  print STDERR <<EOT;
usage: $0 [-r] TYPE INPUT.idl...

-r         raw mode, do not preprocess input

TYPE       topic-type we want to use

INPUT.idl  input files: these are preprocessed with 'cpp', concatenated
           and then processed.  (It does not care when types are defined
           multiple times, so concatenating them should work.)  Specify
           a - to read stdin.

Note: It cannot parse all valid IDL inputs (in particular, it ignores
things such as unions and constants, and cannot parse some complex
features, &c.); error messages are of low quality.
EOT
  exit 1;
}

my $raw_mode = exists $opts{r};
my $type = shift @ARGV;

# format specifiers for sprintf when serializing integer key fields
my %integer_fmt_tab =
  (int8  => "hhd", uint8 => "hhu",
   int16 => "hd",  uint16 => "hu",
   int32 => "d",   uint32 => "u",
   int64 => "lld", uint64 => "llu");

# maximum fixed length needed in serialized form for each type
my %fixed_size_tab =
  (int8   =>  4, # -128
   uint8  =>  3, #  255
   int16  =>  6, # -32 768
   uint16 =>  5, #  65 535
   int32  => 11, # -2 147 483 648
   uint32 => 10, #  4 294 967 295
   int64  => 20, # -4 611 686 018 427 387 904
   uint64 => 19, #  9 223 372 036 854 775 807
   string =>  0); # no fixed contribution

# Read in all of the input in one big string
undef $/;
my $input = "";
for (@ARGV) {
  if ($raw_mode) {
    open FH, "< $_" or die "error: can't open $_";
  } else {
    open FH, "cpp -xc++ -DOSPL_IDL_COMPILER -I$ENV{OSPL_HOME}/etc/idl $_ |" or die "error: 'cpp $_' failed";
  }
  $input .= <FH>;
  close FH;
}

# @module_stack is an array used as a stack for module nesting,
# everything found in the input is fictitiously contained in a module
# "u", to distinguish all user-defined types from the primitive type
# names used inside this script.
my @module_stack = ("u");

# %types is a hash table mapping fully-qualified type names to their
# definitions; a type definition is either a primitive (the names in
# %fixed_size_tab), the name of a user-defined type (in %types) or a
# reference to an array of types for representing structs. The primitive
# types are explicitly added to %types to simplify further processing.
#
# All enums get mapped to int32 -- just like in C.  Unions,
# floating-point numbers, &c. are simply ignored as they cannot be used
# as keys.  Actually, it can't parse unions yet.
my %types = ();
for (keys %fixed_size_tab) { $types{$_} = $_; }
$types{"u::c_ulong"} = "uint32";
$types{"u::c_time"} = "uint64"; # hack

# The topics are collected in the @topics array.  Each topic in is
# represented as [ TYPE, KEYS ] (an array reference), where TYPE is the
# type name, and KEYS itself is a reference to an array of hash tables
# with the following entries:
#
#   name   the name of the field
#   type   the type -- this must be one of the primitive types in
#          %fixed_size_tab
#
# The name uses the C notation for field references, i.e., separates
# names in nested structs with '.'.  The code generator simply copies
# this to the output.
my @topics = ();

# Tokenizer status:
#
# @pushback_token_list contains already parsed tokens that have been
# pushed back for re-evaluation, allowing token lookahead and injecting
# extra tokens in the input stream.  The latter is sometimes used to
# simplify the parsing of separators by inserting an initial separator.
#
# $input_at_bol is true iff the tokenizer is currently at the start of a
# line.  This enables, e.g., the recognition of "#pragma keylist".
#
# $lineno is the current line number, @fstack tracks {name, line}
# pairs and is updated by "# LINE" directives
my @pushback_token_list = ();
my $input_at_bol = 1;
my $lineno = 1;
my $last_token = "";
my @fstack = ({ name => "<input>", lineno => 1 });

# With everything initialized, parse the input.  Parse errors will cause
# the script to terminate.
parse ();

die "topic $type undefined\n" unless exists $types{"u::$type"};
my @t = grep { $_->[1] eq "u::$type" } @topics;
die "no keylist for type $type\n" if @t == 0;
my @keys = map { $_->{name} } @{$t[0]->[2]};
print "@keys\n";

exit 0;

              ############################################
              ###### TYPE & FIELDNAME => FIELD TYPE ######
              ############################################

sub lookup_field_type {
  my ($fqtype, $field, $type) = @_;
  #print "lookup_field_type $fqtype $field\n";
  my @fs = split (/\./, $field);
  while (@fs > 0) {
    my $f = shift @fs;
    #print "looking for $f\n";
    parse_error ("$fqtype not a struct containing $field (1)") unless ref ($type) eq "ARRAY";
    my $subtype = undef;
    for (@{$type}) {
      # each member is [ NAME, TYPE ], scan until match
      next unless $_->[0] eq $f;
      $subtype = $types{$_->[1]};
    }
    die "$fqtype not a struct containing $field (2)" unless defined $subtype;
    $type = $subtype;
  }
  # might be a typedef of a primitive type
  $type = $types{$type} while $type =~ /^u::/ && exists $types{$type};
  parse_error ("$fqtype.$field not a primitive type ($type)") unless $type !~ /^u::/;
  #print "lookup_field_type $fqtype $field => $type\n";
  return $type;
}

                         #####################
                         ####### PARSER ######
                         #####################

sub parse {
  while (peek_token () ne "EOF") {
    parse_topdecl ();
  }
}

sub parse_topdecl {
  my $tok = peek_token ();
  if ($tok eq "module") { parse_module (); }
  elsif ($tok eq "typedef") { parse_typedef (); }
  elsif ($tok eq "struct") { parse_struct (); }
  elsif ($tok eq "union") { parse_union (); }
  elsif ($tok eq "enum") { parse_enum (); }
  elsif ($tok eq "const") { parse_const (); } 
  elsif ($tok eq "KEYLIST") { parse_keylist (); pushback_token (";", undef); }
  else { parse_error ("parse_topdecl"); }
  next_token (";");
}

sub parse_module {
  my ($tok, $val, $name);
  next_token ("module");
  ($tok, $name) = next_token ("IDENT");
  #print STDERR "begin module $name\n";
  push @module_stack, $name;
  ($tok, $val) = next_token ("{");
  while (($tok = peek_token ()) ne "}") {
    parse_topdecl ();
  }
  next_token ("}");
  pop @module_stack;
  #print STDERR "end module\n";
}

sub fqname {
  my ($name) = @_;
  if ($name =~ /^::/) {
    return "u$name";
  } else {
    return (join ("::", @module_stack))."::$name";
  }
}

sub parse_typedef {
  my ($tok, $type, $name);
  next_token ("typedef");
  $type = parse_type ();
  # insert a "," in the token stream so the loop gets simpler
  pushback_token (",", undef);
  while (peek_token () eq ",") {
    next_token ();
    my ($tok, $name) = next_token ("IDENT");
    if (parse_array_dim ()) { # ignoring arrays
      $types{fqname ($name)} = "ignore";
    } else {
      $types{fqname ($name)} = $type;
    }
    #print STDERR "@{[fqname($name)]} = $types{fqname ($name)}\n";
  }
}

sub parse_struct {
  my ($tok, $val, $name);
  next_token ("struct");
  ($tok, $name) = next_token ("IDENT");
  # assign it a temporary type, so members can refer to it
  $types{fqname ($name)} = "<incomplete>";
  if (peek_token () ne ";") {
    ($tok, $val) = next_token ("{");
    my @members = ();
    while (peek_token () ne "}") {
      push @members, parse_member ();
      next_token (";");
    }
    next_token ("}");
    $types{fqname($name)} = \@members;
  }
  return fqname ($name);
}

sub parse_enum { # all enums get mapped to int32, identifiers are dropped
  my ($tok, $val, $name);
  next_token ("enum");
  ($tok, $name) = next_token ("IDENT");
  $types{fqname ($name)} = "int32";
  ($tok, $val) = next_token ("{");
  my @members = ();
  pushback_token (",", undef);
  while (peek_token () ne "}") {
    next_token (",");
    next_token ("IDENT");
    # not even bothering to parse constant expressions: simply
    # dropping all tokens until next ',' or '}'
    if (peek_token () eq "=") {
      next_token ();
      while (peek_token () !~ /[,}]/) { next_token (); }
    }
  }
  next_token ("}");
  return fqname ($name);
}

sub parse_const { # we can parse (most?) constants, but we drop them
  my ($tok, $val);
  next_token ("const");
  my $type = parse_type ();
  ($tok, $val) = next_token ("IDENT");
  #print STDERR "parse_const: type = $type name = $val\n";
  next_token ("=");
  while (peek_token () ne ";") { # gobble up everything until ';"
    ($tok, $val) = next_token ();
    #print STDERR "  $tok";
    #print STDERR "=$val" if defined $val;
  }
  #print STDERR "\n";
}

sub parse_union { # we can parse them (probably including some illegal ones)
  my ($tok, $val, $name);
  next_token ("union");
  ($tok, $name) = next_token ("IDENT");
  #print STDERR "parse_union: name = $name\n";
  $types{fqname ($name)} = "union";
  if (peek_token () ne ";") {
    next_token ("switch");
    next_token ("(");
    my $disctype = parse_type ();
    #print STDERR "  disc.type = $disctype\n";
    next_token (")");
    next_token ("{");
    while (($tok = peek_token ()) ne "}") {
      if ($tok eq "case") {
        next_token ("case");
        parse_int_or_constname ();
        next_token (":");
      } elsif ($tok eq "default") {
        next_token ("default");
        next_token (":");
      } else {
        parse_member ();
        next_token (";");
      }
    }
    next_token ("}");
  }
  return fqname ($name);
}

sub parse_member {
  my ($tok, $name, $type);
  my $ignore = 0;
  $type = parse_type ();
  return parse_memberlist_nonempty ($type);
}

sub parse_memberlist_nonempty {
  my ($type) = @_;
  my @members = ();
  # insert a "," in the token stream so the loop gets simpler
  pushback_token (",", undef);
  while (peek_token () eq ",") {
    next_token ();
    my ($tok, $name) = next_token ("IDENT");
    if (parse_array_dim ()) { # ignoring arrays
      push @members, [ $name, "ignore" ];
    } else {
      push @members, [ $name, $type ];
    }
  }
  return @members;
}

sub parse_type {
  my ($tok) = peek_token ();
  if ($tok =~ /^(boolean|float|double)$/) { next_token (); return $tok; }
  elsif ($tok =~ /^(octet|char|short|long|unsigned)$/) { return parse_type_int (); }
  elsif ($tok eq "string") { return parse_type_string (); }
  elsif ($tok eq "sequence") { return parse_type_sequence (); }
  elsif ($tok =~ /^(::|IDENT)$/) { return parse_type_user (); }
  elsif ($tok eq "struct") { return parse_struct (); }
  elsif ($tok eq "enum") { return parse_enum (); }
  elsif ($tok eq "union") { return parse_union (); }
  else { parse_error ("parse_type: unexpected token: $tok"); }
}

sub parse_type_int {
  my ($tok, $val) = next_token ();
  my ($prefix, $size) = ("", 0);
  if ($tok eq "octet") { $prefix = "u"; $size = 8; }
  elsif ($tok eq "char") { $size = 8; }
  else {
    if ($tok eq "unsigned") { $prefix = "u"; ($tok, $val) = next_token (); }
    if ($tok eq "short") { $size = 16; }
    elsif ($tok eq "long") { if (peek_token () eq "long") { next_token (); $size = 64; } else { $size = 32; } }
    else { parse_error ("parse_type_prim"); }
  }
  return "${prefix}int${size}";
}

sub parse_type_string {
  my ($tok, $val) = next_token ("string");
  if (peek_token () eq "<") { # bounded string; ignore bound
    next_token ("<");
    parse_int_or_constname ();
    next_token (">");
  }
  return "string";
}

sub parse_type_sequence {
  my ($tok, $val) = next_token ("sequence");
  next_token ("<");
  parse_type ();
  if (peek_token () eq ",") { # bounded sequence; ignore bound
    next_token (",");
    parse_int_or_constname ();
  }
  next_token (">");
  return "sequence";
}

sub parse_array_dim {
  my $isary = 0;
  while (peek_token () eq "[") {
    $isary = 1;
    next_token ("[");
    parse_int_or_constname ();
    next_token ("]");
  }
  return $isary;
}

sub parse_int_or_constname {
  my ($tok, $val) = next_token ();
  if ($tok eq "INT") { return ($tok, $val); }
  elsif ($tok eq "IDENT") {
    my $name = $val;
    while (peek_token () eq "::") {
      next_token ();
      ($tok, $val) = next_token ("IDENT");
      $name = "${name}::$val";
    }
    return ("SYMBOL", $name);
  }
}

sub parse_type_user {
  my ($tok, $val, @cs);
  # collect components of name in @cs
  ($tok, $val) = next_token ();
  my $is_fq = ($tok eq "::");
  my $fqname;
  push @cs, $val unless $tok eq "::";
  # if last token was "::" we must have an identifier; if it was an
  # identifier, we peek at the next one and continue if "::".
  while (1) {
    if ($tok eq "::") {
      ($tok, $val) = next_token ("IDENT");
      push @cs, $val;
    } elsif (peek_token () eq "::") {
      ($tok, $val) = next_token ("::");
    } else {
      last;
    }
  }
  if ($is_fq) {
    # fully qualified name -- but we must still prepend "u"
    $fqname = join "::", ("u", @cs);
    parse_error ("parse_type_user: type $fqname not known") unless exists ${types{$fqname}};
  } else {
    # go up the module hierarchy looking for the name
    my @prefix = @module_stack;
    $fqname = join "::", (@prefix, @cs);
    while (!exists $types{$fqname} && @prefix > 1) {
      pop @prefix;
      $fqname = join "::", (@prefix, @cs);
    }
    if (!exists $types{$fqname}) {
      my $name = join "::", @cs;
      my $scope = join "::", @module_stack;
      parse_error ("parse_type_user: type $name not known in scope $scope");
    }
  }
  #printf STDERR "%s%s => %s\n", ($is_fq ? "::" : ""), (join "::", @cs), $fqname;
  return $fqname;
}

sub parse_keylist {
  my ($tok, $val) = next_token ("KEYLIST");
  #print "parse_keylist\n";
  my @vs = split (/(?:\s|,)+/, $val);
  # type name is first, make it fully qualified including u:: prefix
  my $name = shift @vs;
  my $fqname = fqname ($name);
  #print "name = $name, fqname = $fqname\n";
  #for (@vs) {
  #  print "  X $_\n";
  #}
  parse_error ("#pragma keylist $name: unknown type $fqname") unless exists $types{$fqname};
  parse_error ("#pragma keylist $name: type $fqname is not a struct") unless ref ($types{$fqname}) eq "ARRAY";
  my @ks = ();
  for my $n (@vs) {
    my $type = lookup_field_type ($fqname, $n, $types{$fqname});
    push @ks, { name => $n, type => $type };
  }
  my $mangled_name = $fqname;
  $mangled_name =~ s/^u:://;
  $mangled_name =~ s/::/_/;
  push @topics, [ $mangled_name, $fqname, \@ks ];
}

                        #######################
                        ###### TOKENIZER ######
                        #######################

sub peek_token {
  my ($tok, $val) = peek_token_val ();
  return $tok;
}

sub peek_token_val {
  my ($tok, $val) = next_token ();
  pushback_token ($tok, $val);
  return ($tok, $val);
}

sub pushback_token {
  my ($tok, $val) = @_;
  unshift @pushback_token_list, [ $tok, $val ];
}

sub next_token {
  my ($exp) = @_;
  my ($tok, $val);
  if (@pushback_token_list) {
    my $tvref = shift @pushback_token_list;
    ($tok, $val) = @$tvref;
  } else {
    ($tok, $val) = next_token_1 ();
  }
  if (defined $exp) {
    parse_error ("$exp expected, have $tok") unless $tok eq $exp;
  }
  return ($tok, $val);
}

sub unescape {
  my ($str) = @_;
  $str =~ s/\\x([0-9a-fA-F]{1,2})/chr (eval "0x$1")/ge;
  $str =~ s/\\([0-7]{1,3})/chr (eval "0$1")/ge;
  $str =~ s/\\([0-7]{1,3})/chr (eval "0$1")/ge;
  $str =~ s/(\\[nrt])/$1/gee;
  $str =~ s/\\([\\"])/$1/g;
  return $str;
}

sub process_line_directive {
  my ($arg) = @_;
  $arg =~ s/^(\d+)\h+//;
  $lineno = $1;
  $arg =~ s/^"((?:[^\\"]|\\\\|\\")*)"\h*//;
  my $name = $1;
  $name = unescape ($name);
  if ($arg eq "" && $name ne $fstack[$#fstack]->{name}) {
    # force push if no flags & file names differ
    $arg = "1"
  }
  while ($arg ne "") {
    $arg =~ s/(\d+)\h*//;
    if ($1 == 1) { # push new file
      #print STDERR "== push $name $lineno\n";
      my $i;
      for ($i = 0; $i < @fstack; $i++) {
        #print STDERR "== scan $fstack[$i]->{name} $fstack[$i]->{lineno}\n";
        last if $fstack[$i]->{name} eq $name && $fstack[$i]->{lineno} eq $lineno;
      }
      #print STDERR "== pop to $i\n";
      pop @fstack while @fstack > $i;
      push @fstack, { name => $name, lineno => $lineno };
    } elsif ($1 == 2) { # pop until name
      while (@fstack > 1 && $fstack[$#fstack]->{name} ne $name) {
        #print STDERR "== pop $fstack[$#fstack]->{name} $fstack[$#fstack]->{lineno}\n";
        pop @fstack;
      }
      $lineno = $fstack[$#fstack]->{lineno};
    } elsif ($1 == 3) {
    } elsif ($1 == 4) {
    } else {
      parse_error ("process_line_directive");
    }
  }
}

sub char_const_1 {
  if ($input =~ /^''/) { parse_error ("char_const_1: empty character constant"); }
  elsif ($input =~ /^'([^\\])'/) { advance (); return $1; }
  elsif ($input =~ /^'\\([\\'])'/) { advance (); return $1; }
  elsif ($input =~ /^'(\\[nrt])'/) { advance (); return (eval "\"$1\""); }
  elsif ($input =~ /^'\\([0-7]{1,3})'/) { advance (); return chr (eval "0$1"); }
  elsif ($input =~ /^'\\x([0-9a-fA-F]{1,2})'/) { advance (); return chr (eval "0x$1"); }
  else { parse_error ("char_const_1: unrecognized constant"); }
}

sub next_token_1 {
  while (1) {
    if ($input_at_bol) {
      if ($input =~ /^\h*#\h+([0-9]+.*)/) { advance (); process_line_directive ($1); next; }
      elsif ($input =~ /^\h*#\h*pragma\h+keylist\h+(.*)/) { advance (); return ("KEYLIST", $1) }
    }

    if ($input =~ /^$/) { return ("EOF", undef); }
    elsif ($input =~ /^\R/) { advance (); $input_at_bol = 1; $lineno++; next; }
    elsif ($input =~ /^(\h+|\/\/.*)/) { advance (); next; }
    elsif ($input =~ /^(::|[=:;,<>(){}\[\]+~*\/%|&^]|-)/) { advance (); return ($1, undef); }
    elsif ($input =~ /^(module|const|enum|struct|sequence|char|octet|short|long|string|float|double|boolean|typedef|unsigned|union|case|default|switch)(?![A-Za-z_0-9])/) { advance (); return ($1, undef); }
    elsif ($input =~ /^([A-Za-z_][A-Za-z_0-9]*)/) { advance (); return ("IDENT", $1); }
    elsif ($input =~ /^([0-9]*\.[0-9]+([Ee][+-]?[0-9]+)?|[0-9]+(\.|[Ee][+-]?[0-9]+))/) { advance (); return ("FLOAT", $1); }
    elsif ($input =~ /^([1-9][0-9]*)/) { advance (); return ("INT", $1); }
    elsif ($input =~ /^(0x[0-9a-fA-F]+)/) { advance (); return ("INT", eval $1); }
    elsif ($input =~ /^(0[0-9]*)/) { advance (); return ("INT", eval $1); }
    # very low quality character and string constant handling
    elsif ($input =~ /^'/) { return ("CHAR", char_const_1 ()); }
    elsif ($input =~ /^"(([^"\\]|\\\\|\\")*)"/) { advance (); return ("STRING", unescape ($1)); }
    else { parse_error ("next_token_1: unrecognized token"); }
  }
}

sub advance {
  my $advance_over = substr ($input, 0, $+[0]);

  $last_token .= $advance_over;
  if (length $last_token > 30) {
    $last_token = substr ($last_token, -30);
  }

  $input = substr ($input, $+[0]);
  $input_at_bol = 0;

  #$advance_over =~ s/\n/\\n/g;
  #$advance_over =~ s/\r/\\r/g;
  #print STDERR "advance: $advance_over\n";
}

sub parse_error {
  my ($msg) = @_;

  print STDERR "error in $fstack[$#fstack]->{name}:$lineno\n";
  for (my $i = $#fstack - 1; $i >= 1; $i--) {
    print STDERR "  included from $fstack[$i]->{name}:$fstack[$i]->{lineno}\n";
  }
  $input =~ /^(.{0,30})/s;
  my $snippet = $1;
  $snippet =~ s/\n/\\n/g;
  $snippet =~ s/\r/\\r/g;
  $last_token =~ s/\n/\\n/g;
  $last_token =~ s/\r/\\r/g;
  print STDERR "  near [*] in: $last_token [*] $snippet\n";
  print STDERR "  note: shifted input for lookahead\n" if @pushback_token_list;
  #my $atbol = $input_at_bol ? "" : " not";
  #print STDERR "while$atbol at bol\n";
  croak "  $msg\n";
}