Android12 应用更新开机动画

项目selinux是打开的，会涉及到权限问题，所以实在具有系统签名的应用中实现。

将动画资源包放到"/data/local/traces"目录

• system/core/rootdir/init.rc

 # For security reasons, /data/local/tmp should always be empty.
 # Do not place files or directories in /data/local/tmp
 mkdir /data/local/tmp 0771 shell shell
 mkdir /data/local/traces 0777 shell shell
 mkdir /data/data 0771 system system encryption=None
 mkdir /data/app-private 0771 system system encryption=Require

在BootAnimation.cpp中添加路径

• /frameworks/base/cmds/bootanimation/BootAnimation.cpp

+static const char CUSTOM_BOOTANIMATION_FILE[] = "/data/local/traces/bootanimation.zip";
 static const char OEM_BOOTANIMATION_FILE[] = "/oem/media/bootanimation.zip";
 static const char PRODUCT_BOOTANIMATION_DARK_FILE[] = "/product/media/bootanimation-dark.zip";
 static const char PRODUCT_BOOTANIMATION_FILE[] = "/product/media/bootanimation.zip";
@@ -583,7 +584,7 @@ void BootAnimation::findBootAnimationFile() {
     }
 
     const bool playDarkAnim = android::base::GetIntProperty("ro.boot.theme", 0) == 1;
     // 将添加的路径放在第一位
-    static const std::vector<std::string> bootFiles = {
+    static const std::vector<std::string> bootFiles = {CUSTOM_BOOTANIMATION_FILE,
         APEX_BOOTANIMATION_FILE, playDarkAnim ? PRODUCT_BOOTANIMATION_DARK_FILE : PRODUCT_BOOTANIMATION_FILE,
         OEM_BOOTANIMATION_FILE, SYSTEM_BOOTANIMATION_FILE
     };
     ...
 // 获取可用开机动画路径
 bool BootAnimation::findBootAnimationFileInternal(const std::vector<std::string> &files) {
     for (const std::string& f : files) {
         if (access(f.c_str(), R_OK) == 0) {
             mZipFileName = f.c_str();
             return true;
         }
     }
     return false;
 }

添加权限

• /device/mediatek/sepolicy/basic/non_plat/bootanim.te

+allow bootanim trace_data_file:dir { search read };
+allow bootanim trace_data_file:file { read open map };

• /device/mediatek/sepolicy/basic/non_plat/system_app.te

+allow system_app trace_data_file:dir { search read create write add_name remove_name };
+allow system_app trace_data_file:file { read create write open getattr setattr unlink };

复制zip包到指定路径

private static final String DEST_PATH = "/data/local/traces/bootanimation.zip";
public boolean setSystemBootAnimation(String path) {
		File file = new File(path);
		if (file.exists()){
			try {
				File destFile = new File(DEST_PATH);
				Runtime.getRuntime().exec("chmod 777" + DEST_PATH);
				if (destFile.exists()){
					destFile.delete();
				}

				FileInputStream fis = new FileInputStream(path);
				FileOutputStream fos = new FileOutputStream(DEST_PATH);
				byte[] buffer = new byte[1024];
				int byteRead;
				while (-1 != (byteRead = fis.read(buffer))){
					fos.write(buffer, 0, byteRead);
				}

				fis.close();
				fos.flush();
				fos.close();
			} catch (IOException e){
				e.printStackTrace();
				return false;
			}
		}

		File nFile = new File(DEST_PATH);
		if (nFile.exists()){
			try {
				Files.setPosixFilePermissions(nFile.toPath(),
						PosixFilePermissions.fromString("rw-rw-rw-"));
			} catch (IOException e) {
				e.printStackTrace();
				return false;
			}
		}
		return true;
	}

需要系统签名，包在data目录下，恢复出厂设置会被清除。
如果项目的selinux是关闭的，也可以自己创建其他路径

• system/core/rootdir/init.rc

mkdir /data/local/animation 0777 shell shell