Add wrappers to handle dyanmically loading libs

Alc/ALc.c

@@ -44,6 +44,9 @@ DEFINE_GUID(IID_IAudioRenderClient, 0xf294acfc, 0x3146, 0x4483, 0xa7,0xbf, 0xad,
 #include <stdio.h>
 #include <memory.h>
 #include <ctype.h>
+#ifdef HAVE_DLFCN_H
+#include <dlfcn.h>
+#endif
 
 #include "alMain.h"
 #include "alSource.h"
@@ -1065,6 +1068,65 @@ void LeaveCriticalSection(CRITICAL_SECTION *cs)
 }
 #endif
 
+#if defined(_WIN32)
+void *LoadLib(const char *name)
+{
+    HANDLE handle;
+
+    handle = LoadLibraryA(name);
+    if(handle == NULL)
+        AL_PRINT("Failed to open %s\n", name);
+    return handle;
+}
+
+void CloseLib(void *handle)
+{ FreeLibrary((HANDLE)handle); }
+
+void *GetSymbol(void *handle, const char *name)
+{
+    void *ret;
+
+    ret = (void*)GetProcAddress((HANDLE)handle, name);
+    if(ret == NULL)
+        AL_PRINT("Failed to load %s\n", name);
+    return ret;
+}
+
+#elif defined(HAVE_DLFCN_H)
+
+void *LoadLib(const char *name)
+{
+    const char *err;
+    void *handle;
+
+    dlerror();
+    handle = dlopen(name, RTLD_NOW);
+    if((err=dlerror()) != NULL)
+    {
+        AL_PRINT("Failed to open %s: %s\n", name, err);
+        handle = NULL;
+    }
+    return handle;
+}
+
+void CloseLib(void *handle)
+{ dlclose(handle); }
+
+void *GetSymbol(void *handle, const char *name)
+{
+    const char *err;
+    void *sym;
+
+    dlerror();
+    sym = dlsym(handle, name);
+    if((err=dlerror()) != NULL)
+    {
+        AL_PRINT("Failed to load %s: %s\n", name, err);
+        sym = NULL;
+    }
+    return sym;
+}
+#endif
 
 static void LockLists(void)
 {

OpenAL32/Include/alMain.h

@@ -192,6 +192,8 @@ typedef DWORD tls_type;
 #define tls_get(x) TlsGetValue((x))
 #define tls_set(x, a) TlsSetValue((x), (a))
 
+#define HAVE_DYNLOAD 1
+
 #else
 
 #include <unistd.h>
@@ -261,8 +263,14 @@ static __inline void Sleep(ALuint t)
     while(nanosleep(&tv, &rem) == -1 && errno == EINTR)
         tv = rem;
 }
+
 #define min(x,y) (((x)<(y))?(x):(y))
 #define max(x,y) (((x)>(y))?(x):(y))
+
+#if defined(HAVE_DLFCN_H)
+#define HAVE_DYNLOAD 1
+#endif
+
 #endif
 
 #include "alListener.h"
@@ -577,6 +585,14 @@ void al_print(const char *fname, unsigned int line, const char *fmt, ...)
              PRINTF_STYLE(3,4);
 #define AL_PRINT(...) al_print(__FILE__, __LINE__, __VA_ARGS__)
 
+
+#if defined(_WIN32) || defined(HAVE_DLFCN_H)
+#define HAVE_DYNLOAD 1
+void *LoadLib(const char *name);
+void CloseLib(void *handle);
+void *GetSymbol(void *handle, const char *name);
+#endif
+
 extern ALdouble ConeScale;
 extern ALdouble ZScale;