NAME

ExtUtils::Typemaps - Read/Write/Modify Perl/XS typemap files

SYNOPSIS

  # read/create file
  my $typemap = ExtUtils::Typemaps->new(file => 'typemap');
  # alternatively create an in-memory typemap
  # $typemap = ExtUtils::Typemaps->new();
  # alternatively create an in-memory typemap by parsing a string
  # $typemap = ExtUtils::Typemaps->new(string => $sometypemap);

  # add a mapping
  $typemap->add_typemap(ctype => 'NV', xstype => 'T_NV');
  $typemap->add_inputmap(
     xstype => 'T_NV', code => '$var = ($type)SvNV($arg);'
  );
  $typemap->add_outputmap(
     xstype => 'T_NV', code => 'sv_setnv($arg, (NV)$var);'
  );
  $typemap->add_string(string => $typemapstring);
                                           # will be parsed and merged

  # remove a mapping (same for remove_typemap and remove_outputmap...)
  $typemap->remove_inputmap(xstype => 'SomeType');

  # save a typemap to a file
  $typemap->write(file => 'anotherfile.map');

  # merge the other typemap into this one
  $typemap->merge(typemap => $another_typemap);

DESCRIPTION

This module can read, modify, create and write Perl XS typemap files. If you don't know what a typemap is, please confer the perlxstut and perlxs manuals.

The module is not entirely round-trip safe: For example it currently simply strips all comments. The order of entries in the maps is, however, preserved.

We check for duplicate entries in the typemap, but do not check for missing TYPEMAP entries for INPUTMAP or OUTPUTMAP entries since these might be hidden in a different typemap.

METHODS

new

Returns a new typemap object. Takes an optional file parameter. If set, the given file will be read. If the file doesn't exist, an empty typemap is returned.

Alternatively, if the string parameter is given, the supplied string will be parsed instead of a file.

file

Get/set the file that the typemap is written to when the write method is called.

add_typemap

Add a TYPEMAP entry to the typemap.

Required named arguments: The ctype (e.g. ctype => 'double') and the xstype (e.g. xstype => 'T_NV').

Optional named arguments: replace => 1 forces removal/replacement of existing TYPEMAP entries of the same ctype. skip => 1 triggers a "first come first serve" logic by which new entries that conflict with existing entries are silently ignored.

As an alternative to the named parameters usage, you may pass in an ExtUtils::Typemaps::Type object as first argument, a copy of which will be added to the typemap. In that case, only the replace or skip named parameters may be used after the object. Example:

  $map->add_typemap($type_obj, replace => 1);

add_inputmap

Add an INPUT entry to the typemap.

Required named arguments: The xstype (e.g. xstype => 'T_NV') and the code to associate with it for input.

Optional named arguments: replace => 1 forces removal/replacement of existing INPUT entries of the same xstype. skip => 1 triggers a "first come first serve" logic by which new entries that conflict with existing entries are silently ignored.

As an alternative to the named parameters usage, you may pass in an ExtUtils::Typemaps::InputMap object as first argument, a copy of which will be added to the typemap. In that case, only the replace or skip named parameters may be used after the object. Example:

  $map->add_inputmap($type_obj, replace => 1);

add_outputmap

Add an OUTPUT entry to the typemap. Works exactly the same as add_inputmap.

add_string

Parses a string as a typemap and merge it into the typemap object.

Required named argument: string to specify the string to parse.

remove_typemap

Removes a TYPEMAP entry from the typemap.

Required named argument: ctype to specify the entry to remove from the typemap.

Alternatively, you may pass a single ExtUtils::Typemaps::Type object.

remove_inputmap

Removes an INPUT entry from the typemap.

Required named argument: xstype to specify the entry to remove from the typemap.

Alternatively, you may pass a single ExtUtils::Typemaps::InputMap object.

remove_outputmap

Removes an OUTPUT entry from the typemap.

Required named argument: xstype to specify the entry to remove from the typemap.

Alternatively, you may pass a single ExtUtils::Typemaps::OutputMap object.

get_typemap

Fetches an entry of the TYPEMAP section of the typemap.

Mandatory named arguments: The ctype of the entry.

Returns the ExtUtils::Typemaps::Type object for the entry if found.

get_inputmap

Fetches an entry of the INPUT section of the typemap.

Mandatory named arguments: The xstype of the entry or the ctype of the typemap that can be used to find the xstype. To wit, the following pieces of code are equivalent:

  my $type = $typemap->get_typemap(ctype => $ctype)
  my $input_map = $typemap->get_inputmap(xstype => $type->xstype);

  my $input_map = $typemap->get_inputmap(ctype => $ctype);

Returns the ExtUtils::Typemaps::InputMap object for the entry if found.

get_outputmap

Fetches an entry of the OUTPUT section of the typemap.

Mandatory named arguments: The xstype of the entry or the ctype of the typemap that can be used to resolve the xstype. (See above for an example.)

Returns the ExtUtils::Typemaps::InputMap object for the entry if found.

write

Write the typemap to a file. Optionally takes a file argument. If given, the typemap will be written to the specified file. If not, the typemap is written to the currently stored file name (see "file" above, this defaults to the file it was read from if any).

as_string

Generates and returns the string form of the typemap.

as_embedded_typemap

Generates and returns the string form of the typemap with the appropriate prefix around it for verbatim inclusion into an XS file as an embedded typemap. This will return a string like

  TYPEMAP: <<END_OF_TYPEMAP
  ... typemap here (see as_string) ...
  END_OF_TYPEMAP

The method takes care not to use a HERE-doc end marker that appears in the typemap string itself.

merge

Merges a given typemap into the object. Note that a failed merge operation leaves the object in an inconsistent state so clone it if necessary.

Mandatory named arguments: Either typemap => $another_typemap_obj or file => $path_to_typemap_file but not both.

Optional arguments: replace => 1 to force replacement of existing typemap entries without warning or skip => 1 to skip entries that exist already in the typemap.

is_empty

Returns a bool indicating whether this typemap is entirely empty.

list_mapped_ctypes

Returns a list of the C types that are mappable by this typemap object.

_get_typemap_hash

Returns a hash mapping the C types to the XS types:

  {
    'char **' => 'T_PACKEDARRAY',
    'bool_t' => 'T_IV',
    'AV *' => 'T_AVREF',
    'InputStream' => 'T_IN',
    'double' => 'T_DOUBLE',
    # ...
  }

This is documented because it is used by ExtUtils::ParseXS, but it's not intended for general consumption. May be removed at any time.

_get_inputmap_hash

Returns a hash mapping the XS types (identifiers) to the corresponding INPUT code:

  {
    'T_CALLBACK' => '   $var = make_perl_cb_$type($arg)
  ',
    'T_OUT' => '    $var = IoOFP(sv_2io($arg))
  ',
    'T_REF_IV_PTR' => '   if (sv_isa($arg, \\"${ntype}\\")) {
    # ...
  }

This is documented because it is used by ExtUtils::ParseXS, but it's not intended for general consumption. May be removed at any time.

_get_outputmap_hash

Returns a hash mapping the XS types (identifiers) to the corresponding OUTPUT code:

  {
    'T_CALLBACK' => '   sv_setpvn($arg, $var.context.value().chp(),
                $var.context.value().size());
  ',
    'T_OUT' => '    {
            GV *gv = (GV *)sv_newmortal();
            gv_init_pvn(gv, gv_stashpvs("$Package",1),
                       "__ANONIO__",10,0);
            if ( do_open(gv, "+>&", 3, FALSE, 0, 0, $var) )
                sv_setsv(
                  $arg,
                  sv_bless(newRV((SV*)gv), gv_stashpv("$Package",1))
                );
            else
                $arg = &PL_sv_undef;
         }
  ',
    # ...
  }

This is documented because it is used by ExtUtils::ParseXS, but it's not intended for general consumption. May be removed at any time.

_get_prototype_hash

Returns a hash mapping the C types of the typemap to their corresponding prototypes.

  {
    'char **' => '$',
    'bool_t' => '$',
    'AV *' => '$',
    'InputStream' => '$',
    'double' => '$',
    # ...
  }

This is documented because it is used by ExtUtils::ParseXS, but it's not intended for general consumption. May be removed at any time.

clone

Creates and returns a clone of a full typemaps object.

Takes named parameters: If shallow is true, the clone will share the actual individual type/input/outputmap objects, but not share their storage. Use with caution. Without shallow, the clone will be fully independent.

tidy_type

Function to (heuristically) canonicalize a C type. Works to some degree with C++ types.

    $halfway_canonical_type = tidy_type($ctype);

Moved from ExtUtils::ParseXS.

CAVEATS

Inherits some evil code from ExtUtils::ParseXS.

SEE ALSO

The parser is heavily inspired from the one in ExtUtils::ParseXS.

For details on typemaps: perlxstut, perlxs.

AUTHOR

Steffen Mueller <smueller@cpan.org>

COPYRIGHT & LICENSE

Copyright 2009, 2010, 2011, 2012, 2013 Steffen Mueller

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.