Introduce background Download process to android

content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java

Index: content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java b/content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java
index 8654cc5bc4a56916f652fe728741cb45fd1060ff..3b465e22d7618af1bccdf2fab393cf655471086e 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ChildProcessLauncher.java
@@ -4,10 +4,14 @@
 
 package org.chromium.content.browser;
 
+import android.annotation.SuppressLint;
 import android.content.Context;
+import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 import android.graphics.SurfaceTexture;
+import android.os.Build;
+import android.os.Bundle;
 import android.os.ParcelFileDescriptor;
 import android.os.RemoteException;
 import android.text.TextUtils;
@@ -15,6 +19,7 @@ import android.util.Pair;
 import android.view.Surface;
 
 import org.chromium.base.CommandLine;
+import org.chromium.base.CpuFeatures;
 import org.chromium.base.Log;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.TraceEvent;
@@ -24,8 +29,10 @@ import org.chromium.base.annotations.JNINamespace;
 import org.chromium.base.library_loader.Linker;
 import org.chromium.content.app.ChildProcessService;
 import org.chromium.content.app.ChromiumLinkerParams;
+import org.chromium.content.app.DownloadProcessService;
 import org.chromium.content.app.PrivilegedProcessService;
 import org.chromium.content.app.SandboxedProcessService;
+import org.chromium.content.common.ContentSwitches;
 import org.chromium.content.common.IChildProcessCallback;
 import org.chromium.content.common.SurfaceWrapper;
 
@@ -47,11 +54,7 @@ public class ChildProcessLauncher {
     static final int CALLBACK_FOR_GPU_PROCESS = 1;
     static final int CALLBACK_FOR_RENDERER_PROCESS = 2;
     static final int CALLBACK_FOR_UTILITY_PROCESS = 3;
-
-    private static final String SWITCH_PROCESS_TYPE = "type";
-    private static final String SWITCH_RENDERER_PROCESS = "renderer";
-    private static final String SWITCH_UTILITY_PROCESS = "utility";
-    private static final String SWITCH_GPU_PROCESS = "gpu-process";
+    static final int CALLBACK_FOR_DOWNLOAD_PROCESS = 4;
 
     /**
      * Allows specifying the package name for looking up child services
@@ -110,7 +113,7 @@ public class ChildProcessLauncher {
                 mFreeConnectionIndices.add(i);
             }
             mChildClass =
-                inSandbox ? SandboxedProcessService.class : PrivilegedProcessService.class;
+                    inSandbox ? SandboxedProcessService.class : PrivilegedProcessService.class;
             mInSandbox = inSandbox;
         }
 
@@ -567,20 +570,6 @@ public class ChildProcessLauncher {
         }
     }
 
-    private static String getSwitchValue(final String[] commandLine, String switchKey) {
-        if (commandLine == null || switchKey == null) {
-            return null;
-        }
-        // This format should be matched with the one defined in command_line.h.
-        final String switchKeyPrefix = "--" + switchKey + "=";
-        for (String command : commandLine) {
-            if (command != null && command.startsWith(switchKeyPrefix)) {
-                return command.substring(switchKeyPrefix.length());
-            }
-        }
-        return null;
-    }
-
     @CalledByNative
     private static FileDescriptorInfo makeFdInfo(
             int id, int fd, boolean autoClose, long offset, long size) {
@@ -617,13 +606,14 @@ public class ChildProcessLauncher {
 
         int callbackType = CALLBACK_FOR_UNKNOWN_PROCESS;
         boolean inSandbox = true;
-        String processType = getSwitchValue(commandLine, SWITCH_PROCESS_TYPE);
-        if (SWITCH_RENDERER_PROCESS.equals(processType)) {
+        String processType =
+                ContentSwitches.getSwitchValue(commandLine, ContentSwitches.SWITCH_PROCESS_TYPE);
+        if (ContentSwitches.SWITCH_RENDERER_PROCESS.equals(processType)) {
             callbackType = CALLBACK_FOR_RENDERER_PROCESS;
-        } else if (SWITCH_GPU_PROCESS.equals(processType)) {
+        } else if (ContentSwitches.SWITCH_GPU_PROCESS.equals(processType)) {
             callbackType = CALLBACK_FOR_GPU_PROCESS;
             inSandbox = false;
-        } else if (SWITCH_UTILITY_PROCESS.equals(processType)) {
+        } else if (ContentSwitches.SWITCH_UTILITY_PROCESS.equals(processType)) {
             // We only support sandboxed right now.
             callbackType = CALLBACK_FOR_UTILITY_PROCESS;
         } else {
@@ -634,6 +624,38 @@ public class ChildProcessLauncher {
                 callbackType, inSandbox);
     }
 
+    /**
+     * Spawns a background download process. The download process will manage its own lifecyle and
+     * can outlive chrome.

[no sievers, 2016/02/03 22:46:52]

What happens if this gets called repeatedly?
Do you eventually expect this to happen (then maybe it should be
'startDownloadProcessIfNecessary' or so)? Or how do you know that it's still
there?

[qinmin, 2016/02/03 23:37:36]

This could get called repeatedly, keeping track of whether download process is
alive from the browser process doesn't match our description that download
process should manage its own life cycle.
When the 2nd time this gets called, the process should get the download request
from the intent, and update the callback so that it can callback the new browser
process.
Changed the function name to startDownloadProcessIfNecessary

+     *
+     * @param context Context used to obtain the application context.
+     * @param commandLine The child process command line argv.
+     */
+    @SuppressLint("NewApi")
+    @CalledByNative
+    private static void startDownloadProcess(Context context, final String[] commandLine) {
+        assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2;
+        String processType =
+                ContentSwitches.getSwitchValue(commandLine, ContentSwitches.SWITCH_PROCESS_TYPE);
+        assert ContentSwitches.SWITCH_DOWNLOAD_PROCESS.equals(processType);
+
+        Intent intent = new Intent();
+        intent.setClass(context, DownloadProcessService.class);
+        intent.setPackage(context.getPackageName());
+        intent.putExtra(ChildProcessConstants.EXTRA_COMMAND_LINE, commandLine);
+        Bundle bundle =
+                createsServiceBundle(commandLine, null, Linker.getInstance().getSharedRelros());
+        // Pid doesn't matter for download process.
+        bundle.putBinder(ChildProcessConstants.EXTRA_CHILD_PROCESS_CALLBACK,
+                createCallback(0, CALLBACK_FOR_DOWNLOAD_PROCESS).asBinder());
+        intent.putExtras(bundle);
+        ChromiumLinkerParams linkerParams = getLinkerParamsForNewConnection();
+        if (linkerParams != null) {
+            linkerParams.addIntentExtras(intent);
+        }
+        context.startService(intent);
+    }
+
     private static void startInternal(
             Context context,
             final String[] commandLine,
@@ -675,6 +697,23 @@ public class ChildProcessLauncher {
         }
     }
 
+    /**
+     * Create the common bundle to be passed to child processes.
+     * @param context Application context.
+     * @param commandLine Command line params to be passed to the service.
+     * @param linkerParams Linker params to start the service.
+     */
+    protected static Bundle createsServiceBundle(
+            String[] commandLine, FileDescriptorInfo[] filesToBeMapped, Bundle sharedRelros) {
+        Bundle bundle = new Bundle();
+        bundle.putStringArray(ChildProcessConstants.EXTRA_COMMAND_LINE, commandLine);
+        bundle.putParcelableArray(ChildProcessConstants.EXTRA_FILES, filesToBeMapped);
+        bundle.putInt(ChildProcessConstants.EXTRA_CPU_COUNT, CpuFeatures.getCount());
+        bundle.putLong(ChildProcessConstants.EXTRA_CPU_FEATURES, CpuFeatures.getMask());
+        bundle.putBundle(Linker.EXTRA_LINKER_SHARED_RELROS, sharedRelros);
+        return bundle;
+    }
+
     @VisibleForTesting
     static void triggerConnectionSetup(
             final ChildProcessConnection connection,
@@ -806,6 +845,15 @@ public class ChildProcessLauncher {
                 return ChildProcessLauncher.getSurfaceTextureSurface(surfaceTextureId,
                         childProcessId);
             }
+
+            @Override
+            public void onDownloadStarted(boolean started, int downloadId) {
+                // TODO(qinmin): call native to cancel or proceed with the download.
+                if (callbackType != CALLBACK_FOR_DOWNLOAD_PROCESS) {
+                    Log.e(TAG, "Illegal callback for non-download process.");
+                    return;
+                }
+            }
         };
     }