Add SDL2 sources

SDL2-2.0.12/src/loadso/dlopen/SDL_sysloadso.c

@@ -0,0 +1,89 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+#ifdef SDL_LOADSO_DLOPEN
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+/* System dependent library loading routines                           */
+
+#include <stdio.h>
+#include <dlfcn.h>
+
+#include "SDL_loadso.h"
+
+#if SDL_VIDEO_DRIVER_UIKIT
+#include "../../video/uikit/SDL_uikitvideo.h"
+#endif
+
+void *
+SDL_LoadObject(const char *sofile)
+{
+    void *handle;
+    const char *loaderror;
+
+#if SDL_VIDEO_DRIVER_UIKIT
+    if (!UIKit_IsSystemVersionAtLeast(8.0)) {
+        SDL_SetError("SDL_LoadObject requires iOS 8+");
+        return NULL;
+    }
+#endif
+
+    handle = dlopen(sofile, RTLD_NOW|RTLD_LOCAL);
+    loaderror = dlerror();
+    if (handle == NULL) {
+        SDL_SetError("Failed loading %s: %s", sofile, loaderror);
+    }
+    return (handle);
+}
+
+void *
+SDL_LoadFunction(void *handle, const char *name)
+{
+    void *symbol = dlsym(handle, name);
+    if (symbol == NULL) {
+        /* append an underscore for platforms that need that. */
+        SDL_bool isstack;
+        size_t len = 1 + SDL_strlen(name) + 1;
+        char *_name = SDL_small_alloc(char, len, &isstack);
+        _name[0] = '_';
+        SDL_strlcpy(&_name[1], name, len);
+        symbol = dlsym(handle, _name);
+        SDL_small_free(_name, isstack);
+        if (symbol == NULL) {
+            SDL_SetError("Failed loading %s: %s", name,
+                         (const char *) dlerror());
+        }
+    }
+    return (symbol);
+}
+
+void
+SDL_UnloadObject(void *handle)
+{
+    if (handle != NULL) {
+        dlclose(handle);
+    }
+}
+
+#endif /* SDL_LOADSO_DLOPEN */
+
+/* vi: set ts=4 sw=4 expandtab: */