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NAME

FFI::Util - Some useful pointer utilities when writing FFI modules

VERSION

version 0.07

SYNOPSIS

 use FFI::Util;

DESCRIPTION

This module provides some useful memory manipulation that is either difficult or impossible in pure Perl. It was originally intended to be used by Archive::Libarchive::FFI, but it may be useful in other projects.

FUNCTIONS

locate_module_share_lib

 my $path = locate_module_share_lib();
 my $path = locate_module_share_lib($module_name, $module_filename);

Returns the path to the shared library for the current module, or the module specified by $module_name (example: Foo::Bar) $module_filename(example /full/path/Foo/Bar.pm).

scalar_to_buffer

 my($ptr, $size) = scalar_to_buffer $scalar;

Given a scalar string value, return a pointer to where the data is stored and the size of the scalar in bytes.

buffer_to_scalar

 my $scalar = buffer_to_scalar($ptr, $size);

Given a pointer to a memory location and a size, construct a new scalar with the same content and size.

deref_ptr_get

 my $ptr2 = deref_ptr_get($ptr1);

equivalent to

 void *ptr1;
 void *ptr2;
 *ptr2 = *ptr1;

deref_ptr_set

 deref_ptr_set($ptr1, $ptr2);

equivalent to

 void **ptr1;
 void *ptr2;
 *ptr1 = ptr2;

deref_str_get

 my $string = deref_str_get($ptr);

equivalent to

 const char *string;
 const char **ptr;
 string = *ptr;

deref_str_set

 deref_str_set($ptr, $string);

equivalent to

 const char **ptr;
 const char *string;
 *ptr = string;

deref_int_get

 my $integer = deref_int_get($ptr);

equivalent to

 int *ptr;
 int integer;
 integer = *ptr;

deref_int_set

 deref_int_set($ptr, $integer);

equivalent to

 int *ptr;
 int integer;
 *ptr = integer;

deref_uint_get

 my $unsigned_integer = deref_uint_get($ptr);

equivalent to

 unsigned int unsigned_integer;
 unsigned int *ptr;
 unsigned_integer = *ptr;

deref_uint_set

 deref_uint_set($ptr, $unsigned_integer);

equivalent to

 unsigned int *ptr;
 unsigned int unsigned_integer;
 *ptr = unsigned_integer;

deref_short_get

 my $short_integer = deref_short_get($ptr);

equivalent to

 short short_integer;
 short *ptr;
 short_integer = *ptr;

deref_short_set

 deref_short_set($ptr, $short_integer);

equivalent to

 short *ptr;
 short short_integer;
 *ptr = short_integer;

deref_ushort_get

 my $unsigned_short_integer = deref_ushort_get($ptr);

equivalent to

 unsigned short unsigned_short_integer;
 unsigned short *ptr;
 unsigned unsigned_short_integer = *ptr;

deref_ushort_set

 deref_ushort_set($ptr, $unsigned_short_integer);

equivalent to

 unsigned short *ptr;
 unsigned short unsigned_short_integer;
 *ptr = unsigned_short_integer;

deref_long_get

 my $long_integer = deref_long_get($ptr);

equivalent to

 long long_integer;
 long *ptr;
 long_integer = *ptr;

deref_long_set

 deref_long_set($ptr, $long_integer);

equivalent to

 long *ptr;
 long long_integer;
 *ptr = long_integer;

deref_ulong_get

 my $unsigned_long_integer = deref_ulong_get($ptr);

equivalent to

 unsigned long unsigned_long_integer;
 unsigned long *ptr;
 unsigned unsigned_long_integer = *ptr;

deref_ulong_set

 deref_ulong_set($ptr, $unsigned_long_integer);

equivalent to

 unsigned long *ptr;
 unsigned long unsigned_long_integer;
 *ptr = unsigned_long_integer;

deref_char_get

 my $char_integer = deref_char_get($ptr);

equivalent to

 char char_integer;
 char *ptr;
 char_integer = *ptr;

deref_char_set

 deref_char_set($ptr, $char_integer);

equivalent to

 char *ptr;
 char char_integer;
 *ptr = char_integer;

deref_uchar_get

 my $unsigned_char_integer = deref_uchar_get($ptr);

equivalent to

 unsigned char unsigned char_integer;
 unsigned char *ptr;
 unsigned_char_integer = *ptr;

deref_uchar_set

 deref_uchar_set($ptr, $unsigned_char_integer);

equivalent to

 unsigned char *ptr;
 unsigned char unsigned_char_integer;
 *ptr = unsigned_char_integer;

deref_float_get

 my $single_float = deref_float_get($ptr);

equivalent to

 float single_float;
 float *ptr;
 single_float = *ptr;

deref_float_set

 deref_float_set($ptr, $single_float);

equivalent to

 float *ptr;
 float single_float;
 *ptr = single_float;

deref_double_get

 my $double_float = deref_double_get($ptr);

equivalent to

 double double_float;
 double *ptr;
 double_float = *ptr;

deref_double_set

 deref_double_set($ptr, $double_float);

equivalent to

 double *ptr;
 double double_float;
 *ptr = double_float;

deref_int64_get

 my $int64 = deref_int64_get($ptr);

equivalent to

 int64_t int64;
 int64_t *ptr;
 int64 = *ptr;

deref_int64_set

 deref_int64_set($ptr, $int64);

equivalent to

 int64_t *ptr;
 int64_t int64;
 *ptr = int64;

deref_uint64_get

 my $uint64 = deref_uint64_get($ptr);

equivalent to

 uint64_t uint64;
 uint64_t *ptr;
 uint64 = *ptr;

deref_uint64_set

 deref_uint64_set($ptr, $uint64);

equivalent to

 uint64_t *ptr;
 uint64_t uint64;
 *ptr = uint64;

deref_dev_t_get

Alias for appropriate derf_..._get if dev_t is provided by your compiler.

deref_dev_t_set

Alias for appropriate derf_..._set if dev_t is provided by your compiler.

deref_gid_t_get

Alias for appropriate derf_..._get if gid_t is provided by your compiler.

deref_gid_t_set

Alias for appropriate derf_..._set if gid_t is provided by your compiler.

deref_size_t_get

Alias for appropriate derf_..._get if size_t is provided by your compiler.

deref_size_t_set

Alias for appropriate derf_..._set if size_t is provided by your compiler.

deref_time_t_get

Alias for appropriate derf_..._get if time_t is provided by your compiler.

deref_time_t_set

Alias for appropriate derf_..._set if time_t is provided by your compiler.

deref_uid_t_get

Alias for appropriate derf_..._get if uid_t is provided by your compiler.

deref_uid_t_set

Alias for appropriate derf_..._set if uid_t is provided by your compiler.

SEE ALSO

Module::Build::FFI
FFI::Raw

AUTHOR

Graham Ollis <plicease@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2013 by Graham Ollis.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.