NAME

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

SYNOPSIS

  use ExtUtils::ParseXS::Utilities qw(
    standard_typemap_locations
    trim_whitespace
    tidy_type
    C_string
    valid_proto_string
    process_typemaps
    make_targetable
    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.

`tidy_type()`

Purpose
Rationalize any asterisks (*) by joining them into bunches, removing interior whitespace, then trimming leading and trailing whitespace.
Arguments
```
    ($ret_type) = tidy_type($_);
```
String to be cleaned up.
Return Value
String cleaned up.

`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.

`make_targetable()`

Purpose
Populate %targetable. This constitutes a refinement of the output of process_typemaps() with respect to its fourth output, $output_expr_ref.
Arguments
```
  %targetable = make_targetable($output_expr_ref);
```
Single hash reference: the fourth such ref returned by process_typemaps().
Return Value
Hash.

`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.