sm指令分析

1, 概述

Sm主要和android机器的存储相关。

主要命令有list-disks/ list-volumes等

2,详细流程

Sm.java很简单,所以直接附上整个java类,如下

public final class Sm {    private static final String TAG = "Sm";    IMountService mSm;    private String[] mArgs;    private int mNextArg;    private String mCurArgData;    public static void main(String[] args) {        boolean success = false;        try {            new Sm().run(args);            success = true;        } catch (Exception e) {            if (e instanceof IllegalArgumentException) {                showUsage();            }            Log.e(TAG, "Error", e);            System.err.println("Error: " + e);        }        System.exit(success ? 0 : 1);    }    public void run(String[] args) throws Exception {        if (args.length < 1) {            throw new IllegalArgumentException();        }        mSm = IMountService.Stub.asInterface(ServiceManager.getService("mount"));        if (mSm == null) {            throw new RemoteException("Failed to find running mount service");        }        mArgs = args;        String op = args[0];        mNextArg = 1;        if ("list-disks".equals(op)) {            runListDisks();        } else if ("list-volumes".equals(op)) {            runListVolumes();        } else if ("has-adoptable".equals(op)) {            runHasAdoptable();        } else if ("get-primary-storage-uuid".equals(op)) {            runGetPrimaryStorageUuid();        } else if ("set-force-adoptable".equals(op)) {            runSetForceAdoptable();        } else if ("partition".equals(op)) {            runPartition();        } else if ("mount".equals(op)) {            runMount();        } else if ("unmount".equals(op)) {            runUnmount();        } else if ("format".equals(op)) {            runFormat();        } else if ("benchmark".equals(op)) {            runBenchmark();        } else if ("forget".equals(op)) {            runForget();        } else {            throw new IllegalArgumentException();        }    }    public void runListDisks() throws RemoteException {        final boolean onlyAdoptable = "adoptable".equals(nextArg());        final DiskInfo[] disks = mSm.getDisks();        for (DiskInfo disk : disks) {            if (!onlyAdoptable || disk.isAdoptable()) {                System.out.println(disk.getId());            }        }    }    public void runListVolumes() throws RemoteException {        final String filter = nextArg();        final int filterType;        if ("public".equals(filter)) {            filterType = VolumeInfo.TYPE_PUBLIC;        } else if ("private".equals(filter)) {            filterType = VolumeInfo.TYPE_PRIVATE;        } else if ("emulated".equals(filter)) {            filterType = VolumeInfo.TYPE_EMULATED;        } else {            filterType = -1;        }        final VolumeInfo[] vols = mSm.getVolumes(0);        for (VolumeInfo vol : vols) {            if (filterType == -1 || filterType == vol.getType()) {                final String envState = VolumeInfo.getEnvironmentForState(vol.getState());                System.out.println(vol.getId() + " " + envState + " " + vol.getFsUuid());            }        }    }    public void runHasAdoptable() {        System.out.println(SystemProperties.getBoolean(StorageManager.PROP_HAS_ADOPTABLE, false));    }    public void runGetPrimaryStorageUuid() throws RemoteException {        System.out.println(mSm.getPrimaryStorageUuid());    }    public void runSetForceAdoptable() throws RemoteException {        final boolean forceAdoptable = Boolean.parseBoolean(nextArg());        mSm.setDebugFlags(forceAdoptable ? StorageManager.DEBUG_FORCE_ADOPTABLE : 0,                StorageManager.DEBUG_FORCE_ADOPTABLE);    }    public void runPartition() throws RemoteException {        final String diskId = nextArg();        final String type = nextArg();        if ("public".equals(type)) {            mSm.partitionPublic(diskId);        } else if ("private".equals(type)) {            mSm.partitionPrivate(diskId);        } else if ("mixed".equals(type)) {            final int ratio = Integer.parseInt(nextArg());            mSm.partitionMixed(diskId, ratio);        } else {            throw new IllegalArgumentException("Unsupported partition type " + type);        }    }    public void runMount() throws RemoteException {        final String volId = nextArg();        mSm.mount(volId);    }    public void runUnmount() throws RemoteException {        final String volId = nextArg();        mSm.unmount(volId);    }    public void runFormat() throws RemoteException {        final String volId = nextArg();        mSm.format(volId);    }    public void runBenchmark() throws RemoteException {        final String volId = nextArg();        mSm.benchmark(volId);    }    public void runForget() throws RemoteException{        final String fsUuid = nextArg();        if ("all".equals(fsUuid)) {            mSm.forgetAllVolumes();        } else {            mSm.forgetVolume(fsUuid);        }    }    private String nextArg() {        if (mNextArg >= mArgs.length) {            return null;        }        String arg = mArgs[mNextArg];        mNextArg++;        return arg;    }    private static int showUsage() {        System.err.println("usage: sm list-disks [adoptable]");        System.err.println("       sm list-volumes [public|private|emulated|all]");        System.err.println("       sm has-adoptable");        System.err.println("       sm get-primary-storage-uuid");        System.err.println("       sm set-force-adoptable [true|false]");        System.err.println("");        System.err.println("       sm partition DISK [public|private|mixed] [ratio]");        System.err.println("       sm mount VOLUME");        System.err.println("       sm unmount VOLUME");        System.err.println("       sm format VOLUME");        System.err.println("       sm benchmark VOLUME");        System.err.println("");        System.err.println("       sm forget [UUID|all]");        System.err.println("");        return 1;    }}