ExtUtils::CBuilder - Compile and link C code for Perl modules

NAME

ExtUtils::CBuilder - Compile and link C code for Perl modules

SYNOPSIS

  use ExtUtils::CBuilder;

  my $b = ExtUtils::CBuilder->new(%options);
  $obj_file = $b->compile(source => 'MyModule.c');
  $lib_file = $b->link(objects => $obj_file);

DESCRIPTION

This module can build the C portions of Perl modules by invoking the appropriate compilers and linkers in a cross-platform manner. It was motivated by the Module::Build project, but may be useful for other purposes as well. However, it is not intended as a general cross-platform interface to all your C building needs. That would have been a much more ambitious goal!

METHODS

new

Returns a new ExtUtils::CBuilder object. A config parameter lets you override Config.pm settings for all operations performed by the object, as in the following example:

  # Use a different compiler than Config.pm says
  my $b = ExtUtils::CBuilder->new( config =>
                                   { ld => 'gcc' } );

have_compiler

Returns true if the current system has a working C compiler and linker, false otherwise. To determine this, we actually compile and link a sample C library.

compile

Compiles a C source file and produces an object file. The name of the object file is returned. The source file is specified in a source parameter, which is required; the other parameters listed below are optional.

object_file: Specifies the name of the output file to create. Otherwise the object_file() method will be consulted, passing it the name of the source file.
include_dirs: Specifies any additional directories in which to search for header files. May be given as a string indicating a single directory, or as a list reference indicating multiple directories.
extra_compiler_flags: Specifies any additional arguments to pass to the compiler. Should be given as a list reference containing the arguments individually, or if this is not possible, as a string containing all the arguments together.

The operation of this method is also affected by the installarchlib, cccdlflags, ccflags, optimize, and cc entries in Config.pm.

link

Invokes the linker to produce a library file from object files. In scalar context, the name of the library file is returned. In list context, the library file and any temporary files created are returned. A required objects parameter contains the name of the object files to process, either in a string (for one object file) or list reference (for one or more files). The following parameters are optional:

lib_file: Specifies the name of the output library file to create. Otherwise the lib_file() method will be consulted, passing it the name of the first entry in objects.
module_name: Specifies the name of the Perl module that will be created by linking. On platforms that need to do prelinking (Win32, OS/2, etc.) this is a required parameter.
extra_linker_flags: Any additional flags you wish to pass to the linker.

On platforms where need_prelink() returns true, prelink() will be called automatically.

The operation of this method is also affected by the lddlflags, shrpenv, and ld entries in Config.pm.

object_file

 my $object_file = $b->object_file($source_file);

Converts the name of a C source file to the most natural name of an output object file to create from it. For instance, on Unix the source file foo.c would result in the object file foo.o.

lib_file

 my $lib_file = $b->lib_file($object_file);

Converts the name of an object file to the most natural name of a output library file to create from it. For instance, on Mac OS X the object file foo.o would result in the library file foo.bundle.

prelink

On certain platforms like Win32, OS/2, VMS, and AIX, it is necessary to perform some actions before invoking the linker. The ExtUtils::Mksymlists module does this, writing files used by the linker during the creation of shared libraries for dynamic extensions. The names of any files written will be returned as a list.

Several parameters correspond to ExtUtils::Mksymlists::Mksymlists() options, as follows:

    Mksymlists()  prelink_objects()       type
   -------------|-------------------|-------------------
    NAME        |  dl_name          | string (required)
    DLBASE      |  dl_base          | string
    FILE        |  dl_file          | string
    DL_VARS     |  dl_vars          | array reference
    DL_FUNCS    |  dl_funcs         | hash reference
    FUNCLIST    |  dl_func_list     | array reference
    IMPORTS     |  dl_imports       | hash reference

Please see the documentation for ExtUtils::Mksymlists for the details of what these parameters do.

need_prelink

Returns true on platforms where prelink() should be called during linking, and false otherwise.

TO DO

Currently this has only been tested on Unix and doesn't contain any of the Windows-specific code from the Module::Build project. I'll do that next.

HISTORY

This module is an outgrowth of the Module::Build project, to which there have been many contributors. Notably, Randy W. Sims submitted lots of code to support 3 compilers on Windows and helped with various other platform-specific issues.

AUTHOR

Ken Williams, kwilliams@cpan.org