userspace: add susfs lib

manager: completed susfs support check prctl syscall

userspace/susfs/.gitignore

@@ -0,0 +1,2 @@
+/obj
+/libs

userspace/susfs/jni/Android.mk

@@ -0,0 +1,6 @@
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := susfs
+LOCAL_SRC_FILES := susfs.c
+include $(BUILD_EXECUTABLE)

userspace/susfs/jni/Application.mk

@@ -0,0 +1,3 @@
+APP_ABI := arm64-v8a x86_64
+APP_PLATFORM := android-24
+APP_STL := none

userspace/susfs/jni/susfs.c

@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/prctl.h>
+
+#define KERNEL_SU_OPTION 0xDEADBEEF
+#define CMD_SUSFS_SHOW_VERSION 0x555e1
+
+int main(int argc, char *argv[]) {
+    int error = -1;
+    char version[16];
+
+    // Check for arguments
+    if (argc < 2) {
+        fprintf(stderr, "Usage: %s <version|support>\n", argv[0]);
+        return 1;
+    }
+
+    // If 'version' is given, show version
+    if (strcmp(argv[1], "version") == 0) {
+        prctl(KERNEL_SU_OPTION, CMD_SUSFS_SHOW_VERSION, version, NULL, &error);
+        if (!error) {
+            printf("%s\n", version);
+        } else {
+            fprintf(stderr, "Failed to retrieve version\n");
+        }
+    }
+    // If 'support' is given, check if version starts with 'v'
+    else if (strcmp(argv[1], "support") == 0) {
+        prctl(KERNEL_SU_OPTION, CMD_SUSFS_SHOW_VERSION, version, NULL, &error);
+        if (!error) {
+            if (version[0] == 'v') {
+                printf("Supported\n");
+            } else {
+                printf("Unsupported\n");
+            }
+        } else {
+            fprintf(stderr, "Failed to retrieve version\n");
+        }
+    } else {
+        fprintf(stderr, "Invalid argument: %s\n", argv[1]);
+        return 1;
+    }
+
+    return 0;
+}