ExtUtils::ParseXS::Utilities

Section: Perl Programmers Reference Guide (3perl)
Updated: 2019-04-20
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NAME

ExtUtils::ParseXS::Utilities - Subroutines used with ExtUtils::ParseXS

SYNOPSIS

  use ExtUtils::ParseXS::Utilities qw(
    standard_typemap_locations
    trim_whitespace
    C_string
    valid_proto_string
    process_typemaps
    map_type
    standard_XS_defs
    assign_func_args
    analyze_preprocessor_statements
    set_cond
    Warn
    blurt
    death
    check_conditional_preprocessor_statements
    escape_file_for_line_directive
    report_typemap_failure
  );

SUBROUTINES

The following functions are not considered to be part of the public interface. They are documented here for the benefit of future maintainers of this module.

standard_typemap_locations()

•

Purpose

Provide a list of filepaths where typemap files may be found. The filepaths --- relative paths to files (not just directory paths) --- appear in this list in lowest-to-highest priority.

The highest priority is to look in the current directory.

  'typemap'

The second and third highest priorities are to look in the parent of the current directory and a directory called lib/ExtUtils underneath the parent directory.

  '../typemap',
  '../lib/ExtUtils/typemap',

The fourth through ninth highest priorities are to look in the corresponding grandparent, great-grandparent and great-great-grandparent directories.

  '../../typemap',
  '../../lib/ExtUtils/typemap',
  '../../../typemap',
  '../../../lib/ExtUtils/typemap',
  '../../../../typemap',
  '../../../../lib/ExtUtils/typemap',

The tenth and subsequent priorities are to look in directories named ExtUtils which are subdirectories of directories found in @INC --- provided a file named typemap actually exists in such a directory. Example:

  '/usr/local/lib/perl5/5.10.1/ExtUtils/typemap',

However, these filepaths appear in the list returned by "standard_typemap_locations()" in reverse order, i.e., lowest-to-highest.

  '/usr/local/lib/perl5/5.10.1/ExtUtils/typemap',
  '../../../../lib/ExtUtils/typemap',
  '../../../../typemap',
  '../../../lib/ExtUtils/typemap',
  '../../../typemap',
  '../../lib/ExtUtils/typemap',
  '../../typemap',
  '../lib/ExtUtils/typemap',
  '../typemap',
  'typemap'

•

Arguments

  my @stl = standard_typemap_locations( \@INC );

Reference to @INC.

•

Return Value

Array holding list of directories to be searched for typemap files.

trim_whitespace()

•

Purpose

Perform an in-place trimming of leading and trailing whitespace from the first argument provided to the function.

•

Argument

  trim_whitespace($arg);

•

Return Value

None. Remember: this is an in-place modification of the argument.

C_string()

•

Purpose

Escape backslashes ("\") in prototype strings.

•

Arguments

      $ProtoThisXSUB = C_string($_);

String needing escaping.

•

Return Value

Properly escaped string.

valid_proto_string()

•

Purpose

Validate prototype string.

•

Arguments

String needing checking.

•

Return Value

Upon success, returns the same string passed as argument.

Upon failure, returns 0.

process_typemaps()

•

Purpose

Process all typemap files.

•

Arguments

  my $typemaps_object = process_typemaps( $args{typemap}, $pwd );

List of two elements: "typemap" element from %args; current working directory.

•

Return Value

Upon success, returns an ExtUtils::Typemaps object.

map_type()

•

Purpose

Performs a mapping at several places inside "PARAGRAPH" loop.

•

Arguments

  $type = map_type($self, $type, $varname);

List of three arguments.

•

Return Value

String holding augmented version of second argument.

standard_XS_defs()

•: Purpose
Writes to the ".c" output file certain preprocessor directives and function headers needed in all such files.
•: Arguments
None.
•: Return Value
Returns true.

assign_func_args()

•

Purpose

Perform assignment to the "func_args" attribute.

•

Arguments

  $string = assign_func_args($self, $argsref, $class);

List of three elements. Second is an array reference; third is a string.

•

Return Value

String.

analyze_preprocessor_statements()

•

Purpose

Within each function inside each Xsub, print to the .c output file certain preprocessor statements.

•

Arguments

      ( $self, $XSS_work_idx, $BootCode_ref ) =
        analyze_preprocessor_statements(
          $self, $statement, $XSS_work_idx, $BootCode_ref
        );

List of four elements.

•

Return Value

Modifed values of three of the arguments passed to the function. In particular, the "XSStack" and "InitFileCode" attributes are modified.

set_cond()

•: Purpose
•: Arguments
•: Return Value

current_line_number()

•: Purpose
Figures out the current line number in the XS file.
•: Arguments
$self
•: Return Value
The current line number.

Warn()

•: Purpose
•: Arguments
•: Return Value

blurt()

•: Purpose
•: Arguments
•: Return Value

death()

•: Purpose
•: Arguments
•: Return Value

check_conditional_preprocessor_statements()

•: Purpose
•: Arguments
•: Return Value

escape_file_for_line_directive()

•: Purpose
Escapes a given code source name (typically a file name but can also be a command that was read from) so that double-quotes and backslashes are escaped.
•: Arguments
A string.
•: Return Value
A string with escapes for double-quotes and backslashes.

report_typemap_failure

•

Purpose

Do error reporting for missing typemaps.

•

Arguments

The "ExtUtils::ParseXS" object.

An "ExtUtils::Typemaps" object.

The string that represents the C type that was not found in the typemap.

Optionally, the string "death" or "blurt" to choose whether the error is immediately fatal or not. Default: "blurt"

•

Return Value

Returns nothing. Depending on the arguments, this may call "death" or "blurt", the former of which is fatal.