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;
}
}