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-rw-r--r--libjava/java/lang/PosixProcess.java451
-rw-r--r--libjava/java/lang/Runtime.java7
-rw-r--r--libjava/java/lang/natPosixProcess.cc220
3 files changed, 581 insertions, 97 deletions
diff --git a/libjava/java/lang/PosixProcess.java b/libjava/java/lang/PosixProcess.java
index 199391b..fbd6c4c 100644
--- a/libjava/java/lang/PosixProcess.java
+++ b/libjava/java/lang/PosixProcess.java
@@ -1,6 +1,5 @@
// PosixProcess.java - Subclass of Process for POSIX systems.
-
-/* Copyright (C) 1998, 1999 Free Software Foundation
+/* Copyright (C) 1998, 1999, 2004 Free Software Foundation
This file is part of libgcj.
@@ -11,76 +10,466 @@ details. */
package java.lang;
import java.io.File;
+import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
-import java.io.IOException;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
/**
* @author Tom Tromey <tromey@cygnus.com>
* @date May 3, 1999
+ * @author David Daney <ddaney@avtrex.com> Rewrote using
+ * ProcessManager
*/
// This is entirely internal to our implementation.
-
// This file is copied to `ConcreteProcess.java' before compilation.
// Hence the class name apparently does not match the file name.
final class ConcreteProcess extends Process
{
- public native void destroy ();
+ static class ProcessManager extends Thread
+ {
+ /**
+ * A list of {@link ConcreteProcess ConcreteProcesses} to be
+ * started. The queueLock object is used as the lock Object
+ * for all process related operations. To avoid dead lock
+ * ensure queueLock is obtained before ConcreteProcess.
+ */
+ List queue = new LinkedList();
+ private Map pidToProcess = new HashMap();
+ private boolean ready = false;
+ private long reaperPID;
+
+ ProcessManager()
+ {
+ super("ProcessManager");
+ // Don't keep the (main) process from exiting on our account.
+ this.setDaemon(true);
+ }
+
+ /**
+ * Get the ConcreteProcess object with the given pid and
+ * remove it from the map. This method is called from the
+ * native code for {@link #reap()). The mapping is removed so
+ * the ConcreteProcesses can be GCed after they terminate.
+ *
+ * @param p The pid of the process.
+ */
+ private ConcreteProcess removeProcessFromMap(long p)
+ {
+ return (ConcreteProcess) pidToProcess.remove(new Long(p));
+ }
+
+ /**
+ * Put the given ConcreteProcess in the map using the Long
+ * value of its pid as the key.
+ *
+ * @param p The ConcreteProcess.
+ */
+ void addProcessToMap(ConcreteProcess p)
+ {
+ pidToProcess.put(new Long(p.pid), p);
+ }
+
+ /**
+ * Queue up the ConcreteProcess and awake the ProcessManager.
+ * The ProcessManager will start the ConcreteProcess from its
+ * thread so it can be reaped when it terminates.
+ *
+ * @param p The ConcreteProcess.
+ */
+ void startExecuting(ConcreteProcess p)
+ {
+ synchronized (queueLock)
+ {
+ queue.add(p);
+ signalReaper(); // If blocked in waitForSignal().
+ queueLock.notifyAll(); // If blocked in wait();
+ }
+ }
+
+ /**
+ * Block until the ProcessManager thread is ready to accept
+ * commands.
+ */
+ void waitUntilReady()
+ {
+ synchronized (this)
+ {
+ try
+ {
+ while (! ready)
+ wait();
+ }
+ catch (InterruptedException ie)
+ {
+ // Ignore.
+ }
+ }
+ }
+
+ /**
+ * Main Process starting/reaping loop.
+ */
+ public void run()
+ {
+ init();
+ // Now ready to accept requests.
+ synchronized (this)
+ {
+ ready = true;
+ this.notifyAll();
+ }
+
+ for (;;)
+ {
+ try
+ {
+ synchronized (queueLock)
+ {
+ boolean haveMoreChildren = reap();
+ if (! haveMoreChildren && queue.size() == 0)
+ {
+ // This reaper thread could exit, but we
+ // keep it alive for a while in case
+ // someone wants to start more Processes.
+ try
+ {
+ queueLock.wait(1000L);
+ if (queue.size() == 0)
+ {
+ processManager = null;
+ return; // Timed out.
+ }
+ }
+ catch (InterruptedException ie)
+ {
+ // Ignore and exit the thread.
+ return;
+ }
+ }
+ while (queue.size() > 0)
+ {
+ ConcreteProcess p = (ConcreteProcess) queue.remove(0);
+ p.spawn(this);
+ }
+ }
- public int exitValue ()
+ // Wait for a SIGCHLD from either an exiting
+ // process or the startExecuting() method. This
+ // is done outside of the synchronized block to
+ // allow other threads to enter and submit more
+ // jobs.
+ waitForSignal();
+ }
+ catch (Exception ex)
+ {
+ ex.printStackTrace(System.err);
+ }
+ }
+ }
+
+ /**
+ * Setup native signal handlers and other housekeeping things.
+ *
+ */
+ private native void init();
+
+ /**
+ * Block waiting for SIGCHLD.
+ *
+ */
+ private native void waitForSignal();
+
+ /**
+ * Try to reap as many children as possible without blocking.
+ *
+ * @return true if more live children exist.
+ *
+ */
+ private native boolean reap();
+
+ /**
+ * Send SIGCHLD to the reaper thread.
+ */
+ private native void signalReaper();
+ }
+
+ public void destroy()
{
- if (! hasExited)
- throw new IllegalThreadStateException("Process has not exited");
+ // Synchronized on the queueLock. This ensures that the reaper
+ // thread cannot be doing a wait() on the child.
+ // Otherwise there would be a race where the OS could
+ // create a process with the same pid between the wait()
+ // and the update of the state which would cause a kill to
+ // the wrong process.
+ synchronized (queueLock)
+ {
+ synchronized (this)
+ {
+ // If there is no ProcessManager we cannot kill.
+ if (state != STATE_TERMINATED)
+ {
+ if (processManager == null)
+ throw new InternalError();
+ nativeDestroy();
+ }
+ }
+ }
+ }
+
+ private native void nativeDestroy();
+
+ public int exitValue()
+ {
+ synchronized (this)
+ {
+ if (state != STATE_TERMINATED)
+ throw new IllegalThreadStateException("Process has not exited");
+ }
return status;
}
- public InputStream getErrorStream ()
+ /**
+ * Called by native code when process exits.
+ *
+ * Already synchronized (this). Close any streams that we can to
+ * conserve file descriptors.
+ *
+ * The outputStream can be closed as any future writes will
+ * generate an IOException due to EPIPE.
+ *
+ * The inputStream and errorStream can only be closed if the user
+ * has not obtained a reference to them AND they have no bytes
+ * available. Since the process has terminated they will never have
+ * any more data available and can safely be replaced by
+ * EOFInputStreams.
+ */
+ void processTerminationCleanup()
+ {
+ try
+ {
+ outputStream.close();
+ }
+ catch (IOException ioe)
+ {
+ // Ignore.
+ }
+ try
+ {
+ if (returnedErrorStream == null && errorStream.available() == 0)
+ {
+ errorStream.close();
+ errorStream = null;
+ }
+ }
+ catch (IOException ioe)
+ {
+ // Ignore.
+ }
+ try
+ {
+ if (returnedInputStream == null && inputStream.available() == 0)
+ {
+ inputStream.close();
+ inputStream = null;
+ }
+ }
+ catch (IOException ioe)
+ {
+ // Ignore.
+ }
+ }
+
+ public synchronized InputStream getErrorStream()
{
- return errorStream;
+ if (returnedErrorStream != null)
+ return returnedErrorStream;
+
+ if (errorStream == null)
+ returnedErrorStream = EOFInputStream.instance;
+ else
+ returnedErrorStream = errorStream;
+
+ return returnedErrorStream;
}
- public InputStream getInputStream ()
+ public synchronized InputStream getInputStream()
{
- return inputStream;
+ if (returnedInputStream != null)
+ return returnedInputStream;
+
+ if (inputStream == null)
+ returnedInputStream = EOFInputStream.instance;
+ else
+ returnedInputStream = inputStream;
+
+ return returnedInputStream;
}
- public OutputStream getOutputStream ()
+ public OutputStream getOutputStream()
{
return outputStream;
}
- public native int waitFor () throws InterruptedException;
+ public int waitFor() throws InterruptedException
+ {
+ synchronized (this)
+ {
+ while (state != STATE_TERMINATED)
+ wait();
+ }
+ return status;
+ }
- // This is used for actual initialization, as we can't write a
- // native constructor.
- public native void startProcess (String[] progarray,
- String[] envp,
- File dir)
- throws IOException;
+ /**
+ * Start this process running. This should only be called by the
+ * ProcessManager.
+ *
+ * @param pm The ProcessManager that made the call.
+ */
+ void spawn(ProcessManager pm)
+ {
+ synchronized (this)
+ {
+ // Do the fork/exec magic.
+ nativeSpawn();
+ // There is no race with reap() in the pidToProcess map
+ // because this is always called from the same thread
+ // doing the reaping.
+ pm.addProcessToMap(this);
+ state = STATE_RUNNING;
+ // Notify anybody waiting on state change.
+ this.notifyAll();
+ }
+ }
+
+ /**
+ * Do the fork and exec.
+ */
+ private native void nativeSpawn();
// This file is copied to `ConcreteProcess.java' before
// compilation. Hence the constructor name apparently does not
// match the file name.
- public ConcreteProcess (String[] progarray,
- String[] envp,
- File dir)
- throws IOException
+ ConcreteProcess(String[] progarray, String[] envp, File dir)
+ throws IOException
{
- startProcess (progarray, envp, dir);
+ // Check to ensure there is something to run, and avoid
+ // dereferencing null pointers in native code.
+ if (progarray[0] == null)
+ throw new NullPointerException();
+
+ this.progarray = progarray;
+ this.envp = envp;
+ this.dir = dir;
+
+ // Start a ProcessManager if there is not one already running.
+ synchronized (queueLock)
+ {
+ if (processManager == null)
+ {
+ processManager = new ProcessManager();
+ processManager.start();
+ processManager.waitUntilReady();
+ }
+
+ // Queue this ConcreteProcess for starting by the ProcessManager.
+ processManager.startExecuting(this);
+ }
+
+ // Wait until ProcessManager has started us.
+ synchronized (this)
+ {
+ while (state == STATE_WAITING_TO_START)
+ {
+ try
+ {
+ wait();
+ }
+ catch (InterruptedException ie)
+ {
+ // FIXME: What to do when interrupted while blocking in a constructor?
+ // Ignore.
+ }
+ }
+ }
+
+ // If there was a problem, re-throw it.
+ if (exception != null)
+ {
+ if (exception instanceof IOException)
+ {
+ IOException ioe = new IOException(exception.toString());
+ ioe.initCause(exception);
+ throw ioe;
+ }
+
+ // Not an IOException. Something bad happened.
+ InternalError ie = new InternalError(exception.toString());
+ ie.initCause(exception);
+ throw ie;
+ }
+
+ // If we get here, all is well, the Process has started.
}
- // The process id. This is cast to a pid_t on the native side.
+ private String[] progarray;
+ private String[] envp;
+ private File dir;
+
+ /** Set by the ProcessManager on problems starting. */
+ private Throwable exception;
+
+ /** The process id. This is cast to a pid_t on the native side. */
private long pid;
- // True when child has exited.
- private boolean hasExited;
+ // FIXME: Why doesn't the friend declaration in ConcreteProcess.h
+ // allow ConcreteProcess$ProcessManager native code access these
+ // when they are private?
+
+ /** Before the process is forked. */
+ static final int STATE_WAITING_TO_START = 0;
+
+ /** After the fork. */
+ static final int STATE_RUNNING = 1;
+
+ /** After exit code has been collected. */
+ static final int STATE_TERMINATED = 2;
- // The exit status, if the child has exited.
- private int status;
+ /** One of STATE_WAITING_TO_START, STATE_RUNNING, STATE_TERMINATED. */
+ int state;
- // The streams.
+ /** The exit status, if the child has exited. */
+ int status;
+
+ /** The streams. */
private InputStream errorStream;
private InputStream inputStream;
private OutputStream outputStream;
+
+ /** InputStreams obtained by the user. Not null indicates that the
+ * user has obtained the stream.
+ */
+ private InputStream returnedErrorStream;
+ private InputStream returnedInputStream;
+
+ /**
+ * Lock Object for all processManager related locking.
+ */
+ private static Object queueLock = new Object();
+ private static ProcessManager processManager;
+
+ static class EOFInputStream extends InputStream
+ {
+ static EOFInputStream instance = new EOFInputStream();
+ public int read()
+ {
+ return -1;
+ }
+ }
}
diff --git a/libjava/java/lang/Runtime.java b/libjava/java/lang/Runtime.java
index 749aa36..b6b8c4f 100644
--- a/libjava/java/lang/Runtime.java
+++ b/libjava/java/lang/Runtime.java
@@ -1,5 +1,5 @@
/* Runtime.java -- access to the VM process
- Copyright (C) 1998, 2002, 2003 Free Software Foundation
+ Copyright (C) 1998, 2002, 2003, 2004 Free Software Foundation
This file is part of GNU Classpath.
@@ -734,8 +734,11 @@ public class Runtime
* @param dir the directory to use, may be null
* @return the newly created process
* @throws NullPointerException if cmd or env have null elements
+ * @throws IOException if the exec fails
*/
- native Process execInternal(String[] cmd, String[] env, File dir);
+ native Process execInternal(String[] cmd, String[] env, File dir)
+ throws IOException;
+
/**
* Get the system properties. This is done here, instead of in System,
diff --git a/libjava/java/lang/natPosixProcess.cc b/libjava/java/lang/natPosixProcess.cc
index fb97020..f6b6f67 100644
--- a/libjava/java/lang/natPosixProcess.cc
+++ b/libjava/java/lang/natPosixProcess.cc
@@ -21,12 +21,16 @@ details. */
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
+#include <unistd.h>
+#include <pthread.h>
#include <gcj/cni.h>
#include <jvm.h>
+#include <java/lang/ConcreteProcess$ProcessManager.h>
#include <java/lang/ConcreteProcess.h>
#include <java/lang/IllegalThreadStateException.h>
+#include <java/lang/InternalError.h>
#include <java/lang/InterruptedException.h>
#include <java/lang/NullPointerException.h>
#include <java/lang/Thread.h>
@@ -42,44 +46,6 @@ using gnu::java::nio::channels::FileChannelImpl;
extern char **environ;
-void
-java::lang::ConcreteProcess::destroy (void)
-{
- if (! hasExited)
- {
- // Really kill it.
- kill ((pid_t) pid, SIGKILL);
- }
-}
-
-jint
-java::lang::ConcreteProcess::waitFor (void)
-{
- if (! hasExited)
- {
- int wstat;
- int r = waitpid ((pid_t) pid, &wstat, 0);
-
- if (r == -1)
- {
- if (java::lang::Thread::interrupted())
- throw new InterruptedException (JvNewStringLatin1 (strerror
- (errno)));
- }
- else
- {
- hasExited = true;
-
- if (WIFEXITED (wstat))
- status = WEXITSTATUS (wstat);
- else
- status = -1;
- }
- }
-
- return status;
-}
-
static char *
new_string (jstring string)
{
@@ -120,14 +86,134 @@ myclose (int &fd)
fd = -1;
}
+// There has to be a signal handler in order to be able to
+// sigwait() on SIGCHLD. The information passed is ignored as it
+// will be recovered by the waitpid() call.
+static void
+sigchld_handler (int)
+{
+ // Ignore.
+}
+
+
+// Get ready to enter the main reaper thread loop.
void
-java::lang::ConcreteProcess::startProcess (jstringArray progarray,
- jstringArray envp,
- java::io::File *dir)
+java::lang::ConcreteProcess$ProcessManager::init ()
{
- using namespace java::io;
+ using namespace java::lang;
+ // Remenber our PID so other threads can kill us.
+ reaperPID = (jlong) pthread_self ();
+
+ // SIGCHLD is blocked in all threads in posix-threads.cc.
+ // Setup the SIGCHLD handler.
+ struct sigaction sa;
+ memset (&sa, 0, sizeof (sa));
+
+ sa.sa_handler = sigchld_handler;
+ // We only want signals when the things exit.
+ sa.sa_flags = SA_NOCLDSTOP;
+
+ if (-1 == sigaction (SIGCHLD, &sa, NULL))
+ goto error;
+
+ // All OK.
+ return;
+
+error:
+ throw new InternalError (JvNewStringUTF (strerror (errno)));
+}
+
+void
+java::lang::ConcreteProcess$ProcessManager::waitForSignal ()
+{
+ using namespace java::lang;
+
+ sigset_t mask;
+ // Wait for SIGCHLD
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+
+ int sig;
+ int c = sigwait (&mask, &sig);
+
+ if (c != 0)
+ goto error;
- hasExited = false;
+ // All OK.
+ return;
+
+error:
+ throw new InternalError (JvNewStringUTF (strerror (c)));
+}
+
+jboolean java::lang::ConcreteProcess$ProcessManager::reap ()
+{
+ using namespace java::lang;
+
+ pid_t pid;
+
+ for (;;)
+ {
+ // Get the return code from a dead child process.
+ int status;
+ pid = waitpid ((pid_t) - 1, &status, WNOHANG);
+ if (pid == -1)
+ {
+ if (errno == ECHILD)
+ return false;
+ else
+ goto error;
+ }
+
+ if (pid == 0)
+ return true; // No children to wait for.
+
+ // Look up the process in our pid map.
+ ConcreteProcess * process = removeProcessFromMap ((jlong) pid);
+
+ if (process)
+ {
+ JvSynchronize sync (process);
+ process->status = WIFEXITED (status) ? WEXITSTATUS (status) : -1;
+ process->state = ConcreteProcess::STATE_TERMINATED;
+ process->processTerminationCleanup();
+ process->notifyAll ();
+ }
+ else
+ {
+ // Unknown child. How did this happen?
+ fprintf (stderr, "Reaped unknown child pid = %ld\n", (long) pid);
+ }
+ }
+
+error:
+ throw new InternalError (JvNewStringUTF (strerror (errno)));
+}
+
+void
+java::lang::ConcreteProcess$ProcessManager::signalReaper ()
+{
+ int c = pthread_kill ((pthread_t) reaperPID, SIGCHLD);
+ if (c == 0)
+ return;
+ // pthread_kill() failed.
+ throw new InternalError (JvNewStringUTF (strerror (c)));
+}
+
+void
+java::lang::ConcreteProcess::nativeDestroy ()
+{
+ int c = kill ((pid_t) pid, SIGKILL);
+ if (c == 0)
+ return;
+ // kill() failed.
+ throw new InternalError (JvNewStringUTF (strerror (errno)));
+}
+
+void
+java::lang::ConcreteProcess::nativeSpawn ()
+{
+ using namespace java::io;
// Initialize all locals here to make cleanup simpler.
char **args = NULL;
@@ -142,7 +228,6 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
errp[1] = -1;
msgp[0] = -1;
msgp[1] = -1;
- java::lang::Throwable *exc = NULL;
errorStream = NULL;
inputStream = NULL;
outputStream = NULL;
@@ -150,8 +235,7 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
try
{
// Transform arrays to native form.
- args = (char **) _Jv_Malloc ((progarray->length + 1)
- * sizeof (char *));
+ args = (char **) _Jv_Malloc ((progarray->length + 1) * sizeof (char *));
// Initialize so we can gracefully recover.
jstring *elts = elements (progarray);
@@ -185,24 +269,32 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
// status.
if (pipe (inp) || pipe (outp) || pipe (errp) || pipe (msgp)
|| fcntl (msgp[1], F_SETFD, FD_CLOEXEC))
- throw new IOException (JvNewStringLatin1 (strerror (errno)));
+ throw new IOException (JvNewStringUTF (strerror (errno)));
// We create the streams before forking. Otherwise if we had an
// error while creating the streams we would have run the child
// with no way to communicate with it.
- errorStream = new FileInputStream (new FileChannelImpl(errp[0], FileChannelImpl::READ));
- inputStream = new FileInputStream (new FileChannelImpl(inp[0], FileChannelImpl::READ));
- outputStream = new FileOutputStream (new FileChannelImpl(outp[1], FileChannelImpl::WRITE));
+ errorStream =
+ new FileInputStream (new
+ FileChannelImpl (errp[0], FileChannelImpl::READ));
+ inputStream =
+ new FileInputStream (new
+ FileChannelImpl (inp[0], FileChannelImpl::READ));
+ outputStream =
+ new FileOutputStream (new FileChannelImpl (outp[1],
+ FileChannelImpl::WRITE));
// We don't use vfork() because that would cause the local
// environment to be set by the child.
- if ((pid = (jlong) fork ()) == -1)
- throw new IOException (JvNewStringLatin1 (strerror (errno)));
- if (pid == 0)
+ // Use temporary for fork result to avoid dirtying an extra page.
+ pid_t pid_tmp;
+ if ((pid_tmp = fork ()) == -1)
+ throw new IOException (JvNewStringUTF (strerror (errno)));
+
+ if (pid_tmp == 0)
{
// Child process, so remap descriptors, chdir and exec.
-
if (envp)
{
// Preserve PATH and LD_LIBRARY_PATH unless specified
@@ -212,16 +304,16 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
environ = env;
if (path_val && getenv ("PATH") == NULL)
{
- char *path_env = (char *) _Jv_Malloc (strlen (path_val)
- + 5 + 1);
+ char *path_env =
+ (char *) _Jv_Malloc (strlen (path_val) + 5 + 1);
strcpy (path_env, "PATH=");
strcat (path_env, path_val);
putenv (path_env);
}
if (ld_path_val && getenv ("LD_LIBRARY_PATH") == NULL)
{
- char *ld_path_env
- = (char *) _Jv_Malloc (strlen (ld_path_val) + 16 + 1);
+ char *ld_path_env =
+ (char *) _Jv_Malloc (strlen (ld_path_val) + 16 + 1);
strcpy (ld_path_env, "LD_LIBRARY_PATH=");
strcat (ld_path_env, ld_path_val);
putenv (ld_path_env);
@@ -264,6 +356,8 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
// Parent. Close extra file descriptors and mark ours as
// close-on-exec.
+ pid = (jlong) pid_tmp;
+
myclose (outp[0]);
myclose (inp[1]);
myclose (errp[1]);
@@ -272,9 +366,9 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
char c;
int r = read (msgp[0], &c, 1);
if (r == -1)
- throw new IOException (JvNewStringLatin1 (strerror (errno)));
+ throw new IOException (JvNewStringUTF (strerror (errno)));
else if (r != 0)
- throw new IOException (JvNewStringLatin1 (strerror (c)));
+ throw new IOException (JvNewStringUTF (strerror (c)));
}
catch (java::lang::Throwable *thrown)
{
@@ -324,15 +418,13 @@ java::lang::ConcreteProcess::startProcess (jstringArray progarray,
myclose (errp[1]);
myclose (msgp[1]);
- exc = thrown;
+ exception = thrown;
}
myclose (msgp[0]);
cleanup (args, env, path);
- if (exc != NULL)
- throw exc;
- else
+ if (exception == NULL)
{
fcntl (outp[1], F_SETFD, FD_CLOEXEC);
fcntl (inp[0], F_SETFD, FD_CLOEXEC);