Add EAX extensions (EAX 2.0-5.0, X-RAM) (#632)

* Add EAX extensions (EAX 2.0-5.0, X-RAM)

* Comment out C++17 leftovers

* Remove everything related to patching

* Update alsoftrc.sample

* Rewrite integration

* Fix GCC compilation under Linux

* Always reset EAX effect properties when loading it into FX slot

1 files changed, 143 insertions, 0 deletions

diff --git a/al/effect.cpp b/al/effect.cpp
index 217cc1c2..79cd7fab 100644
--- a/al/effect.cpp
+++ b/al/effect.cpp
@@ -51,6 +51,11 @@
 #include "opthelpers.h"
 #include "vector.h"
 
+#if ALSOFT_EAX
+#include <cassert>
+
+#include "eax_exception.h"
+#endif // ALSOFT_EAX
 
 const EffectList gEffectList[16]{
     { "eaxreverb",   EAXREVERB_EFFECT,   AL_EFFECT_EAXREVERB },
@@ -745,3 +750,141 @@ void LoadReverbPreset(const char *name, ALeffect *effect)
 
     WARN("Reverb preset '%s' not found\n", name);
 }
+
+#if ALSOFT_EAX
+namespace
+{
+
+class EaxAlEffectException :
+    public EaxException
+{
+public:
+    explicit EaxAlEffectException(
+        const char* message)
+        :
+        EaxException{"[EAX_AL_EFFECT]", message}
+    {
+    }
+}; // EaxAlEffectException
+
+
+} // namespace
+
+
+void ALeffect::eax_initialize()
+{
+    eax_effect = nullptr;
+    eax_effect = eax_create_eax_effect(type, Props);
+}
+
+void ALeffect::eax_al_set_effect(
+    ALenum al_effect_type)
+{
+    if (al_effect_type != AL_EFFECT_NULL)
+    {
+        auto has_effect = false;
+
+        for (const auto &effect_item : gEffectList)
+        {
+            if (al_effect_type == effect_item.val && !DisabledEffects[effect_item.type])
+            {
+                has_effect = true;
+                break;
+            }
+        }
+
+        if (!has_effect)
+        {
+            eax_fail("Effect not available.");
+        }
+    }
+
+    InitEffectParams(this, al_effect_type);
+}
+
+[[noreturn]]
+void ALeffect::eax_fail(
+    const char* message)
+{
+    throw EaxAlEffectException{message};
+}
+
+EaxAlEffectDeleter::EaxAlEffectDeleter(
+    ALCcontext& context) noexcept
+    :
+    context_{&context}
+{
+}
+
+void EaxAlEffectDeleter::operator()(
+    ALeffect* effect) const
+{
+    assert(effect);
+
+    eax_al_delete_effect(*context_, *effect);
+}
+
+EaxAlEffectUPtr eax_create_al_effect(
+    ALCcontext& context,
+    ALenum effect_type)
+{
+#define EAX_PREFIX "[EAX_MAKE_EFFECT] "
+
+    auto& device = *context.mALDevice;
+    std::lock_guard<std::mutex> effect_lock{device.EffectLock};
+
+    // Allocate.
+    //
+    if (!EnsureEffects(&device, 1))
+    {
+        ERR(EAX_PREFIX "%s\n", "Failed to ensure.");
+        return nullptr;
+    }
+
+    auto effect = EaxAlEffectUPtr{AllocEffect(&device), EaxAlEffectDeleter{context}};
+
+    if (!effect)
+    {
+        ERR(EAX_PREFIX "%s\n", "Failed to allocate.");
+        return nullptr;
+    }
+
+    // Set the type.
+    //
+    auto is_supported = (effect_type == AL_EFFECT_NULL);
+
+    if (!is_supported)
+    {
+        for (const auto& effect_item : gEffectList)
+        {
+            if(effect_type == effect_item.val && !DisabledEffects[effect_item.type])
+            {
+                is_supported = true;
+                break;
+            }
+        }
+    }
+
+    if (!is_supported)
+    {
+        ERR(EAX_PREFIX "Effect type 0x%04x not supported.\n", effect_type);
+        return nullptr;
+    }
+
+    InitEffectParams(effect.get(), effect_type);
+
+    return effect;
+
+#undef EAX_PREFIX
+}
+
+void eax_al_delete_effect(
+    ALCcontext& context,
+    ALeffect& effect)
+{
+    auto& device = *context.mALDevice;
+    std::lock_guard<std::mutex> effect_lock{device.EffectLock};
+
+    FreeEffect(&device, &effect);
+}
+#endif // ALSOFT_EAX