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<pre><a name="line-1"></a><span class='hs-comment'>{-# LANGUAGE CPP #-}</span>
<a name="line-2"></a><span class='hs-comment'>{-# OPTIONS_HADDOCK hide #-}</span>
<a name="line-3"></a><span class='hs-comment'>-- GIMP Toolkit (GTK) FFI extras and version dependencies</span>
<a name="line-4"></a><span class='hs-comment'>--</span>
<a name="line-5"></a><span class='hs-comment'>-- Author : Axel Simon</span>
<a name="line-6"></a><span class='hs-comment'>--</span>
<a name="line-7"></a><span class='hs-comment'>-- Created: 22 June 2001</span>
<a name="line-8"></a><span class='hs-comment'>--</span>
<a name="line-9"></a><span class='hs-comment'>-- Copyright (C) 1999-2005 Axel Simon</span>
<a name="line-10"></a><span class='hs-comment'>--</span>
<a name="line-11"></a><span class='hs-comment'>-- This library is free software; you can redistribute it and/or</span>
<a name="line-12"></a><span class='hs-comment'>-- modify it under the terms of the GNU Lesser General Public</span>
<a name="line-13"></a><span class='hs-comment'>-- License as published by the Free Software Foundation; either</span>
<a name="line-14"></a><span class='hs-comment'>-- version 2.1 of the License, or (at your option) any later version.</span>
<a name="line-15"></a><span class='hs-comment'>--</span>
<a name="line-16"></a><span class='hs-comment'>-- This library is distributed in the hope that it will be useful,</span>
<a name="line-17"></a><span class='hs-comment'>-- but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
<a name="line-18"></a><span class='hs-comment'>-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU</span>
<a name="line-19"></a><span class='hs-comment'>-- Lesser General Public License for more details.</span>
<a name="line-20"></a><span class='hs-comment'>--</span>
<a name="line-21"></a><span class='hs-comment'>-- #hide</span>
<a name="line-22"></a>
<a name="line-23"></a><span class='hs-comment'>-- |</span>
<a name="line-24"></a><span class='hs-comment'>--</span>
<a name="line-25"></a><span class='hs-comment'>-- This module serves as an impedance matcher for different compiler</span>
<a name="line-26"></a><span class='hs-comment'>-- versions. It also adds a few FFI utility functions.</span>
<a name="line-27"></a><span class='hs-comment'>--</span>
<a name="line-28"></a>
<a name="line-29"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Glib</span><span class='hs-varop'>.</span><span class='hs-conid'>FFI</span> <span class='hs-layout'>(</span>
<a name="line-30"></a> <span class='hs-varid'>with</span><span class='hs-layout'>,</span>
<a name="line-31"></a> <span class='hs-varid'>nullForeignPtr</span><span class='hs-layout'>,</span>
<a name="line-32"></a> <span class='hs-varid'>maybeNull</span><span class='hs-layout'>,</span>
<a name="line-33"></a> <span class='hs-varid'>newForeignPtr</span><span class='hs-layout'>,</span>
<a name="line-34"></a> <span class='hs-varid'>withForeignPtrs</span><span class='hs-layout'>,</span>
<a name="line-35"></a> <span class='hs-keyword'>module</span> <span class='hs-conid'>Foreign</span><span class='hs-layout'>,</span>
<a name="line-36"></a> <span class='hs-keyword'>module</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>C</span>
<a name="line-37"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-38"></a>
<a name="line-39"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Unsafe</span> <span class='hs-layout'>(</span><span class='hs-varid'>unsafePerformIO</span><span class='hs-layout'>)</span>
<a name="line-40"></a>
<a name="line-41"></a><span class='hs-comment'>-- We should almost certainly not be using the standard free function anywhere</span>
<a name="line-42"></a><span class='hs-comment'>-- in the glib or gtk bindings, so we do not re-export it from this module.</span>
<a name="line-43"></a>
<a name="line-44"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>C</span>
<a name="line-45"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Foreign</span> <span class='hs-varid'>hiding</span> <span class='hs-layout'>(</span><span class='hs-varid'>free</span><span class='hs-layout'>)</span>
<a name="line-46"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Foreign</span> <span class='hs-varid'>hiding</span> <span class='hs-layout'>(</span><span class='hs-varid'>with</span><span class='hs-layout'>,</span> <span class='hs-varid'>newForeignPtr</span><span class='hs-layout'>,</span> <span class='hs-varid'>free</span>
<a name="line-47"></a><span class='hs-cpp'>#if (__GLASGOW_HASKELL__<606)</span>
<a name="line-48"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>withObject</span>
<a name="line-49"></a><span class='hs-cpp'>#endif</span>
<a name="line-50"></a> <span class='hs-layout'>)</span>
<a name="line-51"></a><span class='hs-cpp'>#if (__GLASGOW_HASKELL__>=610)</span>
<a name="line-52"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span>
<a name="line-53"></a><span class='hs-cpp'>#endif</span>
<a name="line-54"></a>
<a name="line-55"></a><a name="with"></a><span class='hs-definition'>with</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Storable</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>b</span>
<a name="line-56"></a><span class='hs-definition'>with</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-varid'>with</span>
<a name="line-57"></a>
<a name="line-58"></a><span class='hs-cpp'>#if (__GLASGOW_HASKELL__>=610)</span>
<a name="line-59"></a><a name="newForeignPtr"></a><span class='hs-definition'>newForeignPtr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FinalizerPtr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>ForeignPtr</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-60"></a><span class='hs-definition'>newForeignPtr</span> <span class='hs-varid'>p</span> <span class='hs-varid'>finalizer</span>
<a name="line-61"></a> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span><span class='hs-varop'>.</span><span class='hs-varid'>newForeignPtr</span> <span class='hs-varid'>p</span> <span class='hs-layout'>(</span><span class='hs-varid'>mkFinalizer</span> <span class='hs-varid'>finalizer</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span>
<a name="line-62"></a>
<a name="line-63"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-keyword'>ccall</span> <span class='hs-str'>"dynamic"</span>
<a name="line-64"></a> <span class='hs-varid'>mkFinalizer</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FinalizerPtr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-65"></a><span class='hs-cpp'>#else</span>
<a name="line-66"></a><span class='hs-definition'>newForeignPtr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>FinalizerPtr</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>ForeignPtr</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-67"></a><span class='hs-definition'>newForeignPtr</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>flip</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-varid'>newForeignPtr</span>
<a name="line-68"></a><span class='hs-cpp'>#endif</span>
<a name="line-69"></a>
<a name="line-70"></a><a name="nullForeignPtr"></a><span class='hs-definition'>nullForeignPtr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ForeignPtr</span> <span class='hs-varid'>a</span>
<a name="line-71"></a><span class='hs-definition'>nullForeignPtr</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>unsafePerformIO</span> <span class='hs-varop'>$</span> <span class='hs-varid'>newForeignPtr_</span> <span class='hs-varid'>nullPtr</span>
<a name="line-72"></a>
<a name="line-73"></a><a name="withForeignPtrs"></a><span class='hs-comment'>-- This is useful when it comes to marshaling lists of GObjects</span>
<a name="line-74"></a><span class='hs-comment'>--</span>
<a name="line-75"></a><span class='hs-definition'>withForeignPtrs</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>ForeignPtr</span> <span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>b</span>
<a name="line-76"></a><span class='hs-definition'>withForeignPtrs</span> <span class='hs-varid'>fptrs</span> <span class='hs-varid'>body</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-77"></a> <span class='hs-varid'>result</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>body</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>unsafeForeignPtrToPtr</span> <span class='hs-varid'>fptrs</span><span class='hs-layout'>)</span>
<a name="line-78"></a> <span class='hs-varid'>mapM_</span> <span class='hs-varid'>touchForeignPtr</span> <span class='hs-varid'>fptrs</span>
<a name="line-79"></a> <span class='hs-varid'>return</span> <span class='hs-varid'>result</span>
<a name="line-80"></a>
<a name="line-81"></a><a name="maybeNull"></a><span class='hs-comment'>-- A marshaling utility function that is used by the code produced by the code</span>
<a name="line-82"></a><span class='hs-comment'>-- generator to marshal return values that can be null</span>
<a name="line-83"></a><span class='hs-definition'>maybeNull</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ptr</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-layout'>(</span><span class='hs-conid'>Maybe</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-84"></a><span class='hs-definition'>maybeNull</span> <span class='hs-varid'>marshal</span> <span class='hs-varid'>genPtr</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-85"></a> <span class='hs-varid'>ptr</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>genPtr</span>
<a name="line-86"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>ptr</span> <span class='hs-varop'>==</span> <span class='hs-varid'>nullPtr</span>
<a name="line-87"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>return</span> <span class='hs-conid'>Nothing</span>
<a name="line-88"></a> <span class='hs-keyword'>else</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>result</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>marshal</span> <span class='hs-layout'>(</span><span class='hs-varid'>return</span> <span class='hs-varid'>ptr</span><span class='hs-layout'>)</span>
<a name="line-89"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-conid'>Just</span> <span class='hs-varid'>result</span><span class='hs-layout'>)</span>
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