Don't load Xposed for minimal framework

When the device is encrypted and a password has to be entered on boot,
a tmpfs is mounted on /data, i.e. the real /data partition isn't
available. Therefore, it doesn't make much sense to load Xposed as we
wouldn't be able to load the modules anyway.

Author: rovo89

app_main2.cpp

@@ -238,8 +238,9 @@ int main(int argc, char* const argv[])
         }
     }
 
-    if (xposed::handleOptions(argc, argv))
-            return 0;
+    if (xposed::handleOptions(argc, argv)) {
+        return 0;
+    }
 
     AppRuntime runtime(argv[0], computeArgBlockSize(argc, argv));
     // Process command line arguments

xposed.cpp

@@ -79,6 +79,11 @@ bool initialize(bool zygote, bool startSystemServer, const char* className, int
         return false;
 #endif
 
+    if (isMinimalFramework()) {
+        ALOGI("Not loading Xposed for minimal framework (encrypted device)");
+        return false;
+    }
+
     xposed->zygote = zygote;
     xposed->startSystemServer = startSystemServer;
     xposed->startClassName = className;
@@ -430,4 +435,18 @@ void dropCapabilities(int8_t keep[]) {
     capset(&header, &cap[0]);
 }
 
+/**
+ * Checks whether the system is booting into a minimal Android framework.
+ * This is the case when the device is encrypted with a password that
+ * has to be entered on boot. /data is a tmpfs in that case, so we
+ * can't load any modules anyway.
+ * The system will reboot later with the full framework.
+ */
+bool isMinimalFramework() {
+    char voldDecrypt[PROPERTY_VALUE_MAX];
+    property_get("vold.decrypt", voldDecrypt, "");
+    return ((strcmp(voldDecrypt, "trigger_restart_min_framework") == 0) ||
+            (strcmp(voldDecrypt, "1") == 0));
+}
+
 }  // namespace xposed

xposed.h

@@ -47,6 +47,7 @@ namespace xposed {
     void onVmCreated(JNIEnv* env);
     void setProcessName(const char* name);
     void dropCapabilities(int8_t keep[] = NULL);
+    bool isMinimalFramework();
 
 }  // namespace xposed