- On Windows, use LoadLibrary/GetProcAddress to load OpenAL function addresses.

The reason for this is that on my system, the static or delay loaded method always picks the (obsolete) system-installed OpenAL version (needed for some old games) which is not wanted here if there's another one in the local ZDoom directory.
This also removes the dependency on the broken import library that comes with OpenAL Soft which causes compile errors with more modern MSVC compilers on default settings.

src/sound/oaldef.h

@@ -0,0 +1,93 @@
+DEFINE_ENTRY(LPALENABLE,alEnable)
+DEFINE_ENTRY(LPALDISABLE, alDisable)
+DEFINE_ENTRY(LPALISENABLED, alIsEnabled)
+DEFINE_ENTRY(LPALGETSTRING, alGetString)
+DEFINE_ENTRY(LPALGETBOOLEANV, alGetBooleanv)
+DEFINE_ENTRY(LPALGETINTEGERV, alGetIntegerv)
+DEFINE_ENTRY(LPALGETFLOATV, alGetFloatv)
+DEFINE_ENTRY(LPALGETDOUBLEV, alGetDoublev)
+DEFINE_ENTRY(LPALGETBOOLEAN, alGetBoolean)
+DEFINE_ENTRY(LPALGETINTEGER, alGetInteger)
+DEFINE_ENTRY(LPALGETFLOAT, alGetFloat)
+DEFINE_ENTRY(LPALGETDOUBLE, alGetDouble)
+DEFINE_ENTRY(LPALGETERROR, alGetError)
+DEFINE_ENTRY(LPALISEXTENSIONPRESENT, alIsExtensionPresent)
+DEFINE_ENTRY(LPALGETPROCADDRESS, alGetProcAddress)
+DEFINE_ENTRY(LPALGETENUMVALUE, alGetEnumValue)
+DEFINE_ENTRY(LPALLISTENERF, alListenerf)
+DEFINE_ENTRY(LPALLISTENER3F, alListener3f)
+DEFINE_ENTRY(LPALLISTENERFV, alListenerfv)
+DEFINE_ENTRY(LPALLISTENERI, alListeneri)
+DEFINE_ENTRY(LPALLISTENER3I, alListener3i)
+DEFINE_ENTRY(LPALLISTENERIV, alListeneriv)
+DEFINE_ENTRY(LPALGETLISTENERF, alGetListenerf)
+DEFINE_ENTRY(LPALGETLISTENER3F, alGetListener3f)
+DEFINE_ENTRY(LPALGETLISTENERFV, alGetListenerfv)
+DEFINE_ENTRY(LPALGETLISTENERI, alGetListeneri)
+DEFINE_ENTRY(LPALGETLISTENER3I, alGetListener3i)
+DEFINE_ENTRY(LPALGETLISTENERIV, alGetListeneriv)
+DEFINE_ENTRY(LPALGENSOURCES, alGenSources)
+DEFINE_ENTRY(LPALDELETESOURCES, alDeleteSources)
+DEFINE_ENTRY(LPALISSOURCE, alIsSource)
+DEFINE_ENTRY(LPALSOURCEF, alSourcef)
+DEFINE_ENTRY(LPALSOURCE3F, alSource3f)
+DEFINE_ENTRY(LPALSOURCEFV, alSourcefv)
+DEFINE_ENTRY(LPALSOURCEI, alSourcei)
+DEFINE_ENTRY(LPALSOURCE3I, alSource3i)
+DEFINE_ENTRY(LPALSOURCEIV, alSourceiv)
+DEFINE_ENTRY(LPALGETSOURCEF, alGetSourcef)
+DEFINE_ENTRY(LPALGETSOURCE3F, alGetSource3f)
+DEFINE_ENTRY(LPALGETSOURCEFV, alGetSourcefv)
+DEFINE_ENTRY(LPALGETSOURCEI, alGetSourcei)
+DEFINE_ENTRY(LPALGETSOURCE3I, alGetSource3i)
+DEFINE_ENTRY(LPALGETSOURCEIV, alGetSourceiv)
+DEFINE_ENTRY(LPALSOURCEPLAYV, alSourcePlayv)
+DEFINE_ENTRY(LPALSOURCESTOPV, alSourceStopv)
+DEFINE_ENTRY(LPALSOURCEREWINDV, alSourceRewindv)
+DEFINE_ENTRY(LPALSOURCEPAUSEV, alSourcePausev)
+DEFINE_ENTRY(LPALSOURCEPLAY, alSourcePlay)
+DEFINE_ENTRY(LPALSOURCESTOP, alSourceStop)
+DEFINE_ENTRY(LPALSOURCEREWIND, alSourceRewind)
+DEFINE_ENTRY(LPALSOURCEPAUSE, alSourcePause)
+DEFINE_ENTRY(LPALSOURCEQUEUEBUFFERS, alSourceQueueBuffers)
+DEFINE_ENTRY(LPALSOURCEUNQUEUEBUFFERS, alSourceUnqueueBuffers)
+DEFINE_ENTRY(LPALGENBUFFERS, alGenBuffers)
+DEFINE_ENTRY(LPALDELETEBUFFERS, alDeleteBuffers)
+DEFINE_ENTRY(LPALISBUFFER, alIsBuffer)
+DEFINE_ENTRY(LPALBUFFERDATA, alBufferData)
+DEFINE_ENTRY(LPALBUFFERF, alBufferf)
+DEFINE_ENTRY(LPALBUFFER3F, alBuffer3f)
+DEFINE_ENTRY(LPALBUFFERFV, alBufferfv)
+DEFINE_ENTRY(LPALBUFFERI, alBufferi)
+DEFINE_ENTRY(LPALBUFFER3I, alBuffer3i)
+DEFINE_ENTRY(LPALBUFFERIV, alBufferiv)
+DEFINE_ENTRY(LPALGETBUFFERF, alGetBufferf)
+DEFINE_ENTRY(LPALGETBUFFER3F, alGetBuffer3f)
+DEFINE_ENTRY(LPALGETBUFFERFV, alGetBufferfv)
+DEFINE_ENTRY(LPALGETBUFFERI, alGetBufferi)
+DEFINE_ENTRY(LPALGETBUFFER3I, alGetBuffer3i)
+DEFINE_ENTRY(LPALGETBUFFERIV, alGetBufferiv)
+DEFINE_ENTRY(LPALDOPPLERFACTOR, alDopplerFactor)
+DEFINE_ENTRY(LPALDOPPLERVELOCITY, alDopplerVelocity)
+DEFINE_ENTRY(LPALSPEEDOFSOUND, alSpeedOfSound)
+DEFINE_ENTRY(LPALDISTANCEMODEL, alDistanceModel)
+DEFINE_ENTRY(LPALCCREATECONTEXT, alcCreateContext)
+DEFINE_ENTRY(LPALCMAKECONTEXTCURRENT, alcMakeContextCurrent)
+DEFINE_ENTRY(LPALCPROCESSCONTEXT, alcProcessContext)
+DEFINE_ENTRY(LPALCSUSPENDCONTEXT, alcSuspendContext)
+DEFINE_ENTRY(LPALCDESTROYCONTEXT, alcDestroyContext)
+DEFINE_ENTRY(LPALCGETCURRENTCONTEXT, alcGetCurrentContext)
+DEFINE_ENTRY(LPALCGETCONTEXTSDEVICE, alcGetContextsDevice)
+DEFINE_ENTRY(LPALCOPENDEVICE, alcOpenDevice)
+DEFINE_ENTRY(LPALCCLOSEDEVICE, alcCloseDevice)
+DEFINE_ENTRY(LPALCGETERROR, alcGetError)
+DEFINE_ENTRY(LPALCISEXTENSIONPRESENT, alcIsExtensionPresent)
+DEFINE_ENTRY(LPALCGETPROCADDRESS, alcGetProcAddress)
+DEFINE_ENTRY(LPALCGETENUMVALUE, alcGetEnumValue)
+DEFINE_ENTRY(LPALCGETSTRING, alcGetString)
+DEFINE_ENTRY(LPALCGETINTEGERV, alcGetIntegerv)
+DEFINE_ENTRY(LPALCCAPTUREOPENDEVICE, alcCaptureOpenDevice)
+DEFINE_ENTRY(LPALCCAPTURECLOSEDEVICE, alcCaptureCloseDevice)
+DEFINE_ENTRY(LPALCCAPTURESTART, alcCaptureStart)
+DEFINE_ENTRY(LPALCCAPTURESTOP, alcCaptureStop)
+DEFINE_ENTRY(LPALCCAPTURESAMPLES, alcCaptureSamples)

src/sound/oalload.h

@@ -0,0 +1,117 @@
+#ifndef OALDEF_H
+#define OALDEF_H
+
+#ifdef _WIN32
+
+#define DEFINE_ENTRY(type, name) static type p_##name;
+#include "oaldef.h"
+#undef DEFINE_ENTRY
+struct oalloadentry
+{
+	const char *name;
+	FARPROC *funcaddr;
+};
+static oalloadentry oalfuncs[] = {
+#define DEFINE_ENTRY(type, name) { #name, (FARPROC*)&p_##name },
+#include "oaldef.h"
+#undef DEFINE_ENTRY
+{ NULL, 0 }
+};
+
+
+#define alEnable p_alEnable
+#define alDisable p_alDisable
+#define alIsEnabled p_alIsEnabled
+#define alGetString p_alGetString
+#define alGetBooleanv p_alGetBooleanv
+#define alGetIntegerv p_alGetIntegerv
+#define alGetFloatv p_alGetFloatv
+#define alGetDoublev p_alGetDoublev
+#define alGetBoolean p_alGetBoolean
+#define alGetInteger p_alGetInteger
+#define alGetFloat p_alGetFloat
+#define alGetDouble p_alGetDouble
+#define alGetError p_alGetError
+#define alIsExtensionPresent p_alIsExtensionPresent
+#define alGetProcAddress p_alGetProcAddress
+#define alGetEnumValue p_alGetEnumValue
+#define alListenerf p_alListenerf
+#define alListener3f p_alListener3f
+#define alListenerfv p_alListenerfv
+#define alListeneri p_alListeneri
+#define alListener3i p_alListener3i
+#define alListeneriv p_alListeneriv
+#define alGetListenerf p_alGetListenerf
+#define alGetListener3f p_alGetListener3f
+#define alGetListenerfv p_alGetListenerfv
+#define alGetListeneri p_alGetListeneri
+#define alGetListener3i p_alGetListener3i
+#define alGetListeneriv p_alGetListeneriv
+#define alGenSources p_alGenSources
+#define alDeleteSources p_alDeleteSources
+#define alIsSource p_alIsSource
+#define alSourcef p_alSourcef
+#define alSource3f p_alSource3f
+#define alSourcefv p_alSourcefv
+#define alSourcei p_alSourcei
+#define alSource3i p_alSource3i
+#define alSourceiv p_alSourceiv
+#define alGetSourcef p_alGetSourcef
+#define alGetSource3f p_alGetSource3f
+#define alGetSourcefv p_alGetSourcefv
+#define alGetSourcei p_alGetSourcei
+#define alGetSource3i p_alGetSource3i
+#define alGetSourceiv p_alGetSourceiv
+#define alSourcePlayv p_alSourcePlayv
+#define alSourceStopv p_alSourceStopv
+#define alSourceRewindv p_alSourceRewindv
+#define alSourcePausev p_alSourcePausev
+#define alSourcePlay p_alSourcePlay
+#define alSourceStop p_alSourceStop
+#define alSourceRewind p_alSourceRewind
+#define alSourcePause p_alSourcePause
+#define alSourceQueueBuffers p_alSourceQueueBuffers
+#define alSourceUnqueueBuffers p_alSourceUnqueueBuffers
+#define alGenBuffers p_alGenBuffers
+#define alDeleteBuffers p_alDeleteBuffers
+#define alIsBuffer p_alIsBuffer
+#define alBufferData p_alBufferData
+#define alBufferf p_alBufferf
+#define alBuffer3f p_alBuffer3f
+#define alBufferfv p_alBufferfv
+#define alBufferi p_alBufferi
+#define alBuffer3i p_alBuffer3i
+#define alBufferiv p_alBufferiv
+#define alGetBufferf p_alGetBufferf
+#define alGetBuffer3f p_alGetBuffer3f
+#define alGetBufferfv p_alGetBufferfv
+#define alGetBufferi p_alGetBufferi
+#define alGetBuffer3i p_alGetBuffer3i
+#define alGetBufferiv p_alGetBufferiv
+#define alDopplerFactor p_alDopplerFactor
+#define alDopplerVelocity p_alDopplerVelocity
+#define alSpeedOfSound p_alSpeedOfSound
+#define alDistanceModel p_alDistanceModel
+#define alcCreateContext p_alcCreateContext
+#define alcMakeContextCurrent p_alcMakeContextCurrent
+#define alcProcessContext p_alcProcessContext
+#define alcSuspendContext p_alcSuspendContext
+#define alcDestroyContext p_alcDestroyContext
+#define alcGetCurrentContext p_alcGetCurrentContext
+#define alcGetContextsDevice p_alcGetContextsDevice
+#define alcOpenDevice p_alcOpenDevice
+#define alcCloseDevice p_alcCloseDevice
+#define alcGetError p_alcGetError
+#define alcIsExtensionPresent p_alcIsExtensionPresent
+#define alcGetProcAddress p_alcGetProcAddress
+#define alcGetEnumValue p_alcGetEnumValue
+#define alcGetString p_alcGetString
+#define alcGetIntegerv p_alcGetIntegerv
+#define alcCaptureOpenDevice p_alcCaptureOpenDevice
+#define alcCaptureCloseDevice p_alcCaptureCloseDevice
+#define alcCaptureStart p_alcCaptureStart
+#define alcCaptureStop p_alcCaptureStop
+#define alcCaptureSamples p_alcCaptureSamples
+
+#endif
+#endif

src/sound/oalsound.cpp

@@ -54,41 +54,58 @@
 #include "i_musicinterns.h"
 #include "tempfiles.h"
 
+#include "oalload.h"
 
 CVAR (String, snd_aldevice, "Default", CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 CVAR (Bool, snd_efx, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
+#ifdef _WIN32
+static HMODULE hmodOpenAL;
+#endif
 
 bool IsOpenALPresent()
 {
 #ifdef NO_OPENAL
 	return false;
 #elif !defined _WIN32
-	return true;	// on non-Windows we cannot delay load the library so it has to be present.
+	return true;
 #else
-	static bool cached_result;
+	static bool cached_result = false;
 	static bool done = false;
 
 	if (!done)
 	{
 		done = true;
-
+		if (hmodOpenAL == NULL)
-		__try
 		{
-			// just call one function from the API to force loading the DLL
+			hmodOpenAL = LoadLibrary(NicePath("$PROGDIR/openal32.dll"));
-			alcGetError(NULL);
+			if (hmodOpenAL == NULL)
-		}
+			{
-		__except (CheckException(GetExceptionCode()))
+				hmodOpenAL = LoadLibrary("openal32.dll");
+				if (hmodOpenAL == NULL)
 				{
-			// FMod could not be delay loaded
 					return false;
 				}
+			}
+			for(int i = 0; oalfuncs[i].name != NULL; i++)
+			{
+				*oalfuncs[i].funcaddr = GetProcAddress(hmodOpenAL, oalfuncs[i].name);
+				if (oalfuncs[i].funcaddr == NULL)
+				{
+					FreeLibrary(hmodOpenAL);
+					hmodOpenAL = NULL;
+					return false;
+				}
+			}
+		}
 		cached_result = true;
 	}
 	return cached_result;
 #endif
 }
 
+
+
 void I_BuildALDeviceList(FOptionValues *opt)
 {
     opt->mValues.Resize(1);