Android/frameworks_base
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Merge "Rewrite selectReadable JNI in Java."

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This commit is contained in:
Elliott Hughes
2014-12-17 18:21:06 +00:00
committed by Gerrit Code Review
parent 6d41504d2c 894724be30
commit e6d63b9462
2 changed files with 27 additions and 101 deletions
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59
core/java/com/android/internal/os/ZygoteInit.java
View File

@@ -16,6 +16,8 @@
package com.android.internal.os;
import static android.system.OsConstants.POLLIN;
import static android.system.OsConstants.POLLOUT;
import static android.system.OsConstants.S_IRWXG;
import static android.system.OsConstants.S_IRWXO;
@@ -32,6 +34,7 @@ import android.os.Trace;
import android.system.ErrnoException;
import android.system.Os;
import android.system.OsConstants;
import android.system.StructPollfd;
import android.util.EventLog;
import android.util.Log;
import android.util.Slog;
@@ -699,34 +702,36 @@ public class ZygoteInit {
private static void runSelectLoop(String abiList) throws MethodAndArgsCaller {
ArrayList<FileDescriptor> fds = new ArrayList<FileDescriptor>();
ArrayList<ZygoteConnection> peers = new ArrayList<ZygoteConnection>();
FileDescriptor[] fdArray = new FileDescriptor[4];
fds.add(sServerSocket.getFileDescriptor());
peers.add(null);
while (true) {
int index;
try {
fdArray = fds.toArray(fdArray);
index = selectReadable(fdArray);
} catch (IOException ex) {
throw new RuntimeException("Error in select()", ex);
StructPollfd[] pollFds = new StructPollfd[fds.size()];
for (int i = 0; i < pollFds.length; ++i) {
pollFds[i] = new StructPollfd();
pollFds[i].fd = fds.get(i);
pollFds[i].events = (short) POLLIN;
}
if (index < 0) {
throw new RuntimeException("Error in select()");
} else if (index == 0) {
ZygoteConnection newPeer = acceptCommandPeer(abiList);
peers.add(newPeer);
fds.add(newPeer.getFileDesciptor());
} else {
boolean done;
done = peers.get(index).runOnce();
if (done) {
peers.remove(index);
fds.remove(index);
try {
Os.poll(pollFds, -1);
} catch (ErrnoException ex) {
throw new RuntimeException("poll failed", ex);
}
for (int i = pollFds.length - 1; i >= 0; --i) {
if ((pollFds[i].revents & POLLIN) == 0) {
continue;
}
if (i == 0) {
ZygoteConnection newPeer = acceptCommandPeer(abiList);
peers.add(newPeer);
fds.add(newPeer.getFileDesciptor());
} else {
boolean done = peers.get(i).runOnce();
if (done) {
peers.remove(i);
fds.remove(i);
}
}
}
}
@@ -766,16 +771,6 @@ public class ZygoteInit {
*/
static native int getpgid(int pid) throws IOException;
/**
* Invokes select() on the provider array of file descriptors (selecting
* for readability only). Array elements of null are ignored.
*
* @param fds non-null; array of readable file descriptors
* @return index of descriptor that is now readable or -1 for empty array.
* @throws IOException if an error occurs
*/
static native int selectReadable(FileDescriptor[] fds) throws IOException;
/**
* Class not instantiable.
*/

69
core/jni/com_android_internal_os_ZygoteInit.cpp
View File

@@ -88,73 +88,6 @@ static jint com_android_internal_os_ZygoteInit_getpgid(
return ret;
}
static jint com_android_internal_os_ZygoteInit_selectReadable (
JNIEnv *env, jobject clazz, jobjectArray fds)
{
if (fds == NULL) {
jniThrowNullPointerException(env, "fds == null");
return -1;
}
jsize length = env->GetArrayLength(fds);
fd_set fdset;
if (env->ExceptionCheck()) {
return -1;
}
FD_ZERO(&fdset);
int nfds = 0;
for (jsize i = 0; i < length; i++) {
jobject fdObj = env->GetObjectArrayElement(fds, i);
if (env->ExceptionCheck()) {
return -1;
}
if (fdObj == NULL) {
continue;
}
int fd = jniGetFDFromFileDescriptor(env, fdObj);
if (env->ExceptionCheck()) {
return -1;
}
FD_SET(fd, &fdset);
if (fd >= nfds) {
nfds = fd + 1;
}
}
int err;
do {
err = select (nfds, &fdset, NULL, NULL, NULL);
} while (err < 0 && errno == EINTR);
if (err < 0) {
jniThrowIOException(env, errno);
return -1;
}
for (jsize i = 0; i < length; i++) {
jobject fdObj = env->GetObjectArrayElement(fds, i);
if (env->ExceptionCheck()) {
return -1;
}
if (fdObj == NULL) {
continue;
}
int fd = jniGetFDFromFileDescriptor(env, fdObj);
if (env->ExceptionCheck()) {
return -1;
}
if (FD_ISSET(fd, &fdset)) {
return (jint)i;
}
}
return -1;
}
/*
* JNI registration.
*/
@@ -168,8 +101,6 @@ static JNINativeMethod gMethods[] = {
(void *) com_android_internal_os_ZygoteInit_setpgid },
{ "getpgid", "(I)I",
(void *) com_android_internal_os_ZygoteInit_getpgid },
{ "selectReadable", "([Ljava/io/FileDescriptor;)I",
(void *) com_android_internal_os_ZygoteInit_selectReadable },
};
int register_com_android_internal_os_ZygoteInit(JNIEnv* env)
{