Fix(iOS 12): fatal issues: dlopen, entitlement

* dlopening the main executable fails
* dlopening dylib fails due to codesign
* Installing PojavLauncher with AppSync causing
extended-virtual-addressing entitlement to be checked improperly

Current issue: it seems that Java 8 is broken on iOS 12

Makefile

@@ -228,6 +228,7 @@ package: native java jre assets
 	@cp -R $(SOURCEDIR)/Natives/*.lproj $(WORKINGDIR)/PojavLauncher.app/ || exit 1
 	$(call DIRCHECK,$(OUTPUTDIR))
 	@cp -R $(WORKINGDIR)/PojavLauncher.app $(OUTPUTDIR)
+	ldid -S $(OUTPUTDIR)/PojavLauncher.app; \
 	ldid -S$(SOURCEDIR)/entitlements.xml $(OUTPUTDIR)/PojavLauncher.app/PojavLauncher; \
 	rm -f $(OUTPUTDIR)/*.ipa; \
 	cd $(OUTPUTDIR); \
@@ -260,6 +261,7 @@ dsym: package
 	
 deploy:
 	@echo '[PojavLauncher v$(VERSION)] deploy - start'
+	@ldid -S $(WORKINGDIR)/PojavLauncher.app; \
 	@ldid -S$(SOURCEDIR)/entitlements.xml $(WORKINGDIR)/PojavLauncher.app/PojavLauncher; \
 	if [ '$(NOSTDIN)' = '1' ]; then \
 		echo '$(SUDOPASS)' | sudo -S mv $(WORKINGDIR)/*.dylib /Applications/PojavLauncher.app/Frameworks/; \

Natives/JavaLauncher.m

@@ -257,7 +257,8 @@ int launchJVM(NSString *username, id launchTarget, int width, int height, int mi
     }
     margv[++margc] = cacio_classpath.UTF8String;
 
-    if (!getEntitlementValue(@"com.apple.developer.kernel.extended-virtual-addressing")) {
+    if (UIDevice.currentDevice.systemVersion.floatValue < 14 ||
+        !getEntitlementValue(@"com.apple.developer.kernel.extended-virtual-addressing")) {
         // In jailed environment, where extended virtual addressing entitlement isn't
         // present (for free dev account), allocating compressed space fails.
         // FIXME: does extended VA allow allocating compressed class space?

Natives/main_hook.m

@@ -2,6 +2,7 @@
 #import "SurfaceViewController.h"
 #import "utils.h"
 
+#include <dlfcn.h>
 #include "external/fishhook/fishhook.h"
 
 void (*orig_abort)();
@@ -32,7 +33,14 @@ void hooked_abort() {
 }
 
 void* hooked_dlopen(const char* path, int mode) {
-    if (path && [@(path) hasSuffix:@"/libawt_xawt.dylib"]) {
+    // iOS 12 refuses to dlopen executables, so here we put a workaround
+    if (path == NULL || [@(path) hasSuffix:@"/PojavLauncher"]) {
+        return orig_dlopen(NULL, mode);
+    }
+
+    if (getenv("POJAV_PREFER_EXTERNAL_JRE") && [@(path) hasSuffix:@"/libawt_xawt.dylib"]) {
+        // In this environment, libawt_xawt is not available/X11 only.
+        // hook dlopen to use our libawt_xawt
         return orig_dlopen([NSString stringWithFormat:@"%s/Frameworks/libawt_xawt.dylib", getenv("BUNDLE_PATH")].UTF8String, mode);
     }
 
@@ -67,14 +75,10 @@ int hooked_open(const char *path, int oflag, ...) {
 }
 
 void init_hookFunctions() {
-    if (getenv("POJAV_PREFER_EXTERNAL_JRE")) {
-        // In this environment, libawt_xawt is not available/X11 only.
-        // hook dlopen to use our libawt_xawt
-        rebind_symbols((struct rebinding[1]){{"dlopen", hooked_dlopen, (void *)&orig_dlopen}}, 1);
-    }
-    rebind_symbols((struct rebinding[3]){
+    rebind_symbols((struct rebinding[4]){
         {"abort", hooked_abort, (void *)&orig_abort},
+        {"dlopen", hooked_dlopen, (void *)&orig_dlopen},
         {"exit", hooked_exit, (void *)&orig_exit},
         {"open", hooked_open, (void *)&orig_open}
-    }, 3);
+    }, 4);
 }

README.md

@@ -73,9 +73,9 @@ PojavLauncher is amazing, and surprisingly stable, and it wouldn't be this way w
 - [LWJGLX](https://github.com/PojavLauncherTeam/lwjglx) (LWJGL2 API compatibility layer for LWJGL3): unknown license.
 - [Alderis](https://github.com/hbang/Alderis) (color picker for iOS < 14): [Apache 2.0 License](https://github.com/hbang/Alderis/blob/master/LICENSE.md).
 - [DBNumberedSlider](https://github.com/khanhduytran0/DBNumberedSlider): [Apache 2.0 License](https://github.com/immago/DBNumberedSlider/blob/master/LICENSE)
-- [fishhook](https://github.com/khanhduytran0/fishhook) (jailed environment usage only): [BSD-3 License](https://github.com/facebook/fishhook/blob/main/LICENSE).
+- [fishhook](https://github.com/khanhduytran0/fishhook): [BSD-3 License](https://github.com/facebook/fishhook/blob/main/LICENSE).
 - [Java Native Access](https://github.com/java-native-access/jna): [Apache 2.0 License](https://github.com/java-native-access/jna/blob/master/LICENSE).
-- [shaderc](https://github.com/khanhduytran0/shaderc) (used by mods that uses Vulkan for rendering): [Apache 2.0 License](https://github.com/google/shaderc/blob/main/LICENSE).
+- [shaderc](https://github.com/khanhduytran0/shaderc) (used by Vulkan rendering mods): [Apache 2.0 License](https://github.com/google/shaderc/blob/main/LICENSE).
 - [TOInsetGroupedTableView](https://github.com/TimOliver/TOInsetGroupedTableView): [MIT License](https://github.com/TimOliver/TOInsetGroupedTableView/blob/master/LICENSE).
 - [AltKit](https://github.com/rileytestut/AltKit)
 - Thanks to [MCHeads](https://mc-heads.net) for providing Minecraft avatars.