/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.os;
import android.net.LocalSocketAddress;
import android.net.LocalSocket;
import android.util.Log;
import dalvik.system.Zygote;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
/*package*/ class ZygoteStartFailedEx extends Exception {
/**
* Something prevented the zygote process startup from happening normally
*/
ZygoteStartFailedEx() {};
ZygoteStartFailedEx(String s) {super(s);}
ZygoteStartFailedEx(Throwable cause) {super(cause);}
}
/**
* Tools for managing OS processes.
*/
public class Process {
private static final String LOG_TAG = "Process";
private static final String ZYGOTE_SOCKET = "zygote";
/**
* Name of a process for running the platform's media services.
* {@hide}
*/
public static final String ANDROID_SHARED_MEDIA = "com.android.process.media";
/**
* Name of the process that Google content providers can share.
* {@hide}
*/
public static final String GOOGLE_SHARED_APP_CONTENT = "com.google.process.content";
/**
* Defines the UID/GID under which system code runs.
*/
public static final int SYSTEM_UID = 1000;
/**
* Defines the UID/GID under which the telephony code runs.
*/
public static final int PHONE_UID = 1001;
/**
* Defines the start of a range of UIDs (and GIDs), going from this
* number to {@link #LAST_APPLICATION_UID} that are reserved for assigning
* to applications.
*/
public static final int FIRST_APPLICATION_UID = 10000;
/**
* Last of application-specific UIDs starting at
* {@link #FIRST_APPLICATION_UID}.
*/
public static final int LAST_APPLICATION_UID = 99999;
/**
* Defines a secondary group id for access to the bluetooth hardware.
*/
public static final int BLUETOOTH_GID = 2000;
/**
* Standard priority of application threads.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_DEFAULT = 0;
/*
* ***************************************
* ** Keep in sync with utils/threads.h **
* ***************************************
*/
/**
* Lowest available thread priority. Only for those who really, really
* don't want to run if anything else is happening.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_LOWEST = 19;
/**
* Standard priority background threads. This gives your thread a slightly
* lower than normal priority, so that it will have less chance of impacting
* the responsiveness of the user interface.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_BACKGROUND = 10;
/**
* Standard priority of threads that are currently running a user interface
* that the user is interacting with. Applications can not normally
* change to this priority; the system will automatically adjust your
* application threads as the user moves through the UI.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_FOREGROUND = -2;
/**
* Standard priority of system display threads, involved in updating
* the user interface. Applications can not
* normally change to this priority.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_DISPLAY = -4;
/**
* Standard priority of the most important display threads, for compositing
* the screen and retrieving input events. Applications can not normally
* change to this priority.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_URGENT_DISPLAY = -8;
/**
* Standard priority of audio threads. Applications can not normally
* change to this priority.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_AUDIO = -16;
/**
* Standard priority of the most important audio threads.
* Applications can not normally change to this priority.
* Use with {@link #setThreadPriority(int)} and
* {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
* {@link java.lang.Thread} class.
*/
public static final int THREAD_PRIORITY_URGENT_AUDIO = -19;
/**
* Minimum increment to make a priority more favorable.
*/
public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1;
/**
* Minimum increment to make a priority less favorable.
*/
public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1;
public static final int SIGNAL_QUIT = 3;
public static final int SIGNAL_KILL = 9;
public static final int SIGNAL_USR1 = 10;
// State for communicating with zygote process
static LocalSocket sZygoteSocket;
static DataInputStream sZygoteInputStream;
static BufferedWriter sZygoteWriter;
/** true if previous zygote open failed */
static boolean sPreviousZygoteOpenFailed;
/**
* Start a new process.
*
* <p>If processes are enabled, a new process is created and the
* static main() function of a <var>processClass</var> is executed there.
* The process will continue running after this function returns.
*
* <p>If processes are not enabled, a new thread in the caller's
* process is created and main() of <var>processClass</var> called there.
*
* <p>The niceName parameter, if not an empty string, is a custom name to
* give to the process instead of using processClass. This allows you to
* make easily identifyable processes even if you are using the same base
* <var>processClass</var> to start them.
*
* @param processClass The class to use as the process's main entry
* point.
* @param niceName A more readable name to use for the process.
* @param uid The user-id under which the process will run.
* @param gid The group-id under which the process will run.
* @param gids Additional group-ids associated with the process.
* @param enableDebugger True if debugging should be enabled for this process.
* @param zygoteArgs Additional arguments to supply to the zygote process.
*
* @return int If > 0 the pid of the new process; if 0 the process is
* being emulated by a thread
* @throws RuntimeException on fatal start failure
*
* {@hide}
*/
public static final int start(final String processClass,
final String niceName,
int uid, int gid, int[] gids,
int debugFlags,
String[] zygoteArgs)
{
if (supportsProcesses()) {
try {
return startViaZygote(processClass, niceName, uid, gid, gids,
debugFlags, zygoteArgs);
} catch (ZygoteStartFailedEx ex) {
Log.e(LOG_TAG,
"Starting VM process through Zygote failed");
throw new RuntimeException(
"Starting VM process through Zygote failed", ex);
}
} else {
// Running in single-process mode
Runnable runnable = new Runnable() {
public void run() {
Process.invokeStaticMain(processClass);
}
};
// Thread constructors must not be called with null names (see spec).
if (niceName != null) {
new Thread(runnable, niceName).start();
} else {
new Thread(runnable).start();
}
return 0;
}
}
/**
* Start a new process. Don't supply a custom nice name.
* {@hide}
*/
public static final int start(String processClass, int uid, int gid,
int[] gids, int debugFlags, String[] zygoteArgs) {
return start(processClass, "", uid, gid, gids,
debugFlags, zygoteArgs);
}
private static void invokeStaticMain(String className) {
Class cl;
Object args[] = new Object[1];
args[0] = new String[0]; //this is argv
try {
cl = Class.forName(className);
cl.getMethod("main", new Class[] { String[].class })
.invoke(null, args);
} catch (Exception ex) {
// can be: ClassNotFoundException,
// NoSuchMethodException, SecurityException,
// IllegalAccessException, IllegalArgumentException
// InvocationTargetException
// or uncaught exception from main()
Log.e(LOG_TAG, "Exception invoking static main on "
+ className, ex);
throw new RuntimeException(ex);
}
}
/** retry interval for opening a zygote socket */
static final int ZYGOTE_RETRY_MILLIS = 500;
/**
* Tries to open socket to Zygote process if not already open. If
* already open, does nothing. May block and retry.
*/
private static void openZygoteSocketIfNeeded()
throws ZygoteStartFailedEx {
int retryCount;
if (sPreviousZygoteOpenFailed) {
/*
* If we've failed before, expect that we'll fail again and
* don't pause for retries.
*/
retryCount = 0;
} else {
retryCount = 10;
}
/*
* See bug #811181: Sometimes runtime can make it up before zygote.
* Really, we'd like to do something better to avoid this condition,
* but for now just wait a bit...
*/
for (int retry = 0
; (sZygoteSocket == null) && (retry < (retryCount + 1))
; retry++ ) {
if (retry > 0) {
try {
Log.i("Zygote", "Zygote not up yet, sleeping...");
Thread.sleep(ZYGOTE_RETRY_MILLIS);
} catch (InterruptedException ex) {
// should never happen
}
}
try {
sZygoteSocket = new LocalSocket();
sZygoteSocket.connect(new LocalSocketAddress(ZYGOTE_SOCKET,
LocalSocketAddress.Namespace.RESERVED));
sZygoteInputStream
= new DataInputStream(sZygoteSocket.getInputStream());
sZygoteWriter =
new BufferedWriter(
new OutputStreamWriter(
sZygoteSocket.getOutputStream()),
256);
Log.i("Zygote", "Process: zygote socket opened");
sPreviousZygoteOpenFailed = false;
break;
} catch (IOException ex) {
if (sZygoteSocket != null) {
try {
sZygoteSocket.close();
} catch (IOException ex2) {
Log.e(LOG_TAG,"I/O exception on close after exception",
ex2);
}
}
sZygoteSocket = null;
}
}
if (sZygoteSocket == null) {
sPreviousZygoteOpenFailed = true;
throw new ZygoteStartFailedEx("connect failed");
}
}
/**
* Sends an argument list to the zygote process, which starts a new child
* and returns the child's pid. Please note: the present implementation
* replaces newlines in the argument list with spaces.
* @param args argument list
* @return PID of new child process
* @throws ZygoteStartFailedEx if process start failed for any reason
*/
private static int zygoteSendArgsAndGetPid(ArrayList<String> args)
throws ZygoteStartFailedEx {
int pid;
openZygoteSocketIfNeeded();
try {
/**
* See com.android.internal.os.ZygoteInit.readArgumentList()
* Presently the wire format to the zygote process is:
* a) a count of arguments (argc, in essence)
* b) a number of newline-separated argument strings equal to count
*
* After the zygote process reads these it will write the pid of
* the child or -1 on failure.
*/
sZygoteWriter.write(Integer.toString(args.size()));
sZygoteWriter.newLine();
int sz = args.size();
for (int i = 0; i < sz; i++) {
String arg = args.get(i);
if (arg.indexOf('\n') >= 0) {
throw new ZygoteStartFailedEx(
"embedded newlines not allowed");
}
sZygoteWriter.write(arg);
sZygoteWriter.newLine();
}
sZygoteWriter.flush();
// Should there be a timeout on this?
pid = sZygoteInputStream.readInt();
if (pid < 0) {
throw new ZygoteStartFailedEx("fork() failed");
}
} catch (IOException ex) {
try {
if (sZygoteSocket != null) {
sZygoteSocket.close();
}
} catch (IOException ex2) {
// we're going to fail anyway
Log.e(LOG_TAG,"I/O exception on routine close", ex2);
}
sZygoteSocket = null;
throw new ZygoteStartFailedEx(ex);
}
return pid;
}
/**
* Starts a new process via the zygote mechanism.
*
* @param processClass Class name whose static main() to run
* @param niceName 'nice' process name to appear in ps
* @param uid a POSIX uid that the new process should setuid() to
* @param gid a POSIX gid that the new process shuold setgid() to
* @param gids null-ok; a list of supplementary group IDs that the
* new process should setgroup() to.
* @param enableDebugger True if debugging should be enabled for this process.
* @param extraArgs Additional arguments to supply to the zygote process.
* @return PID
* @throws ZygoteStartFailedEx if process start failed for any reason
*/
private static int startViaZygote(final String processClass,
final String niceName,
final int uid, final int gid,
final int[] gids,
int debugFlags,
String[] extraArgs)
throws ZygoteStartFailedEx {
int pid;
synchronized(Process.class) {
ArrayList<String> argsForZygote = new ArrayList<String>();
// --runtime-init, --setuid=, --setgid=,
// and --setgroups= must go first
argsForZygote.add("--runtime-init");
argsForZygote.add("--setuid=" + uid);
argsForZygote.add("--setgid=" + gid);
if ((debugFlags & Zygote.DEBUG_ENABLE_DEBUGGER) != 0) {
argsForZygote.add("--enable-debugger");
}
if ((debugFlags & Zygote.DEBUG_ENABLE_CHECKJNI) != 0) {
argsForZygote.add("--enable-checkjni");
}
if ((debugFlags & Zygote.DEBUG_ENABLE_ASSERT) != 0) {
argsForZygote.add("--enable-assert");
}
//TODO optionally enable debuger
//argsForZygote.add("--enable-debugger");
// --setgroups is a comma-separated list
if (gids != null && gids.length > 0) {
StringBuilder sb = new StringBuilder();
sb.append("--setgroups=");
int sz = gids.length;
for (int i = 0; i < sz; i++) {
if (i != 0) {
sb.append(',');
}
sb.append(gids[i]);
}
argsForZygote.add(sb.toString());
}
if (niceName != null) {
argsForZygote.add("--nice-name=" + niceName);
}
argsForZygote.add(processClass);
if (extraArgs != null) {
for (String arg : extraArgs) {
argsForZygote.add(arg);
}
}
pid = zygoteSendArgsAndGetPid(argsForZygote);
}
if (pid <= 0) {
throw new ZygoteStartFailedEx("zygote start failed:" + pid);
}
return pid;
}
/**
* Returns elapsed milliseconds of the time this process has run.
* @return Returns the number of milliseconds this process has return.
*/
public static final native long getElapsedCpuTime();
/**
* Returns the identifier of this process, which can be used with
* {@link #killProcess} and {@link #sendSignal}.
*/
public static final native int myPid();
/**
* Returns the identifier of the calling thread, which be used with
* {@link #setThreadPriority(int, int)}.
*/
public static final native int myTid();
/**
* Returns the identifier of this process's user.
*/
public static final native int myUid();
/**
* Returns the UID assigned to a particular user name, or -1 if there is
* none. If the given string consists of only numbers, it is converted
* directly to a uid.
*/
public static final native int getUidForName(String name);
/**
* Returns the GID assigned to a particular user name, or -1 if there is
* none. If the given string consists of only numbers, it is converted
* directly to a gid.
*/
public static final native int getGidForName(String name);
/**
* Set the priority of a thread, based on Linux priorities.
*
* @param tid The identifier of the thread/process to change.
* @param priority A Linux priority level, from -20 for highest scheduling
* priority to 19 for lowest scheduling priority.
*
* @throws IllegalArgumentException Throws IllegalArgumentException if
* <var>tid</var> does not exist.
* @throws SecurityException Throws SecurityException if your process does
* not have permission to modify the given thread, or to use the given
* priority.
*/
public static final native void setThreadPriority(int tid, int priority)
throws IllegalArgumentException, SecurityException;
/**
* Set the priority of the calling thread, based on Linux priorities. See
* {@link #setThreadPriority(int, int)} for more information.
*
* @param priority A Linux priority level, from -20 for highest scheduling
* priority to 19 for lowest scheduling priority.
*
* @throws IllegalArgumentException Throws IllegalArgumentException if
* <var>tid</var> does not exist.
* @throws SecurityException Throws SecurityException if your process does
* not have permission to modify the given thread, or to use the given
* priority.
*
* @see #setThreadPriority(int, int)
*/
public static final native void setThreadPriority(int priority)
throws IllegalArgumentException, SecurityException;
/**
* Return the current priority of a thread, based on Linux priorities.
*
* @param tid The identifier of the thread/process to change.
*
* @return Returns the current priority, as a Linux priority level,
* from -20 for highest scheduling priority to 19 for lowest scheduling
* priority.
*
* @throws IllegalArgumentException Throws IllegalArgumentException if
* <var>tid</var> does not exist.
*/
public static final native int getThreadPriority(int tid)
throws IllegalArgumentException;
/**
* Determine whether the current environment supports multiple processes.
*
* @return Returns true if the system can run in multiple processes, else
* false if everything is running in a single process.
*/
public static final native boolean supportsProcesses();
/**
* Set the out-of-memory badness adjustment for a process.
*
* @param pid The process identifier to set.
* @param amt Adjustment value -- linux allows -16 to +15.
*
* @return Returns true if the underlying system supports this
* feature, else false.
*
* {@hide}
*/
public static final native boolean setOomAdj(int pid, int amt);
/**
* Change this process's argv[0] parameter. This can be useful to show
* more descriptive information in things like the 'ps' command.
*
* @param text The new name of this process.
*
* {@hide}
*/
public static final native void setArgV0(String text);
/**
* Kill the process with the given PID.
* Note that, though this API allows us to request to
* kill any process based on its PID, the kernel will
* still impose standard restrictions on which PIDs you
* are actually able to kill. Typically this means only
* the process running the caller's packages/application
* and any additional processes created by that app; packages
* sharing a common UID will also be able to kill each
* other's processes.
*/
public static final void killProcess(int pid) {
sendSignal(pid, SIGNAL_KILL);
}
/** @hide */
public static final native int setUid(int uid);
/** @hide */
public static final native int setGid(int uid);
/**
* Send a signal to the given process.
*
* @param pid The pid of the target process.
* @param signal The signal to send.
*/
public static final native void sendSignal(int pid, int signal);
/** @hide */
public static final native int getFreeMemory();
/** @hide */
public static final native void readProcLines(String path,
String[] reqFields, long[] outSizes);
/** @hide */
public static final native int[] getPids(String path, int[] lastArray);
/** @hide */
public static final int PROC_TERM_MASK = 0xff;
/** @hide */
public static final int PROC_ZERO_TERM = 0;
/** @hide */
public static final int PROC_SPACE_TERM = (int)' ';
/** @hide */
public static final int PROC_COMBINE = 0x100;
/** @hide */
public static final int PROC_PARENS = 0x200;
/** @hide */
public static final int PROC_OUT_STRING = 0x1000;
/** @hide */
public static final int PROC_OUT_LONG = 0x2000;
/** @hide */
public static final int PROC_OUT_FLOAT = 0x4000;
/** @hide */
public static final native boolean readProcFile(String file, int[] format,
String[] outStrings, long[] outLongs, float[] outFloats);
/**
* Gets the total Pss value for a given process, in bytes.
*
* @param pid the process to the Pss for
* @return the total Pss value for the given process in bytes,
* or -1 if the value cannot be determined
* @hide
*/
public static final native long getPss(int pid);
}
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