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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
package org.mozilla.gecko.process;
import android.content.ComponentName;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.ServiceInfo;
import androidx.annotation.NonNull;
/* package */ final class ServiceUtils {
private static final String DEFAULT_ISOLATED_CONTENT_SERVICE_NAME_SUFFIX = "0";
private ServiceUtils() {}
/**
* @return StringBuilder containing the name of a service class but not qualifed with any unique
* identifiers.
*/
private static StringBuilder startSvcName(@NonNull final GeckoProcessType type) {
final StringBuilder builder = new StringBuilder(GeckoChildProcessServices.class.getName());
builder.append("$").append(type);
return builder;
}
/**
* Given a service's GeckoProcessType, obtain the name of its class, including any qualifiers that
* are needed to uniquely identify its manifest definition.
*/
public static String buildSvcName(
@NonNull final GeckoProcessType type, final String... suffixes) {
final StringBuilder builder = startSvcName(type);
for (final String suffix : suffixes) {
builder.append(suffix);
}
return builder.toString();
}
/**
* Given a service's GeckoProcessType, obtain the name of its class to be used for the purpose of
* binding as an isolated service.
*
* <p>Content services are defined in the manifest as "tab0" through "tabN" for some value of N.
* For the purposes of binding to an isolated content service, we simply need to repeatedly re-use
* the definition of "tab0", the "0" being stored as the
* DEFAULT_ISOLATED_CONTENT_SERVICE_NAME_SUFFIX constant.
*/
public static String buildIsolatedSvcName(@NonNull final GeckoProcessType type) {
if (type == GeckoProcessType.CONTENT) {
return buildSvcName(type, DEFAULT_ISOLATED_CONTENT_SERVICE_NAME_SUFFIX);
}
// Non-content services do not require any unique IDs
return buildSvcName(type);
}
/**
* Given a service's GeckoProcessType, obtain the unqualified name of its class.
*
* @return The name of the class that hosts the implementation of the service corresponding to
* type, but without any unique identifiers that may be required to actually instantiate it.
*/
private static String buildSvcNamePrefix(@NonNull final GeckoProcessType type) {
return startSvcName(type).toString();
}
/**
* Extracts flags from the manifest definition of a service.
*
* @param context Context to use for extraction
* @param type Service type
* @return flags that are specified in the service's definition in our manifest.
* @see android.content.pm.ServiceInfo for explanation of the various flags.
*/
public static int getServiceFlags(
@NonNull final Context context, @NonNull final GeckoProcessType type) {
final ComponentName component = new ComponentName(context, buildIsolatedSvcName(type));
final PackageManager pkgMgr = context.getPackageManager();
try {
final ServiceInfo svcInfo = pkgMgr.getServiceInfo(component, 0);
// svcInfo is never null
return svcInfo.flags;
} catch (final PackageManager.NameNotFoundException e) {
throw new RuntimeException(e);
}
}
/** Obtain the list of all services defined for |context|. */
private static ServiceInfo[] getServiceList(@NonNull final Context context) {
final PackageInfo packageInfo;
try {
packageInfo =
context
.getPackageManager()
.getPackageInfo(context.getPackageName(), PackageManager.GET_SERVICES);
} catch (final PackageManager.NameNotFoundException e) {
throw new AssertionError("Should not happen: Can't get package info of own package");
}
return packageInfo.services;
}
/**
* Count the number of service definitions in our manifest that satisfy bindings for a particular
* service type.
*
* @param context Context object to use for extracting the service definitions
* @param type The type of service to count
* @return The number of available service definitions.
*/
public static int getServiceCount(
@NonNull final Context context, @NonNull final GeckoProcessType type) {
final ServiceInfo[] svcList = getServiceList(context);
final String serviceNamePrefix = buildSvcNamePrefix(type);
int result = 0;
for (final ServiceInfo svc : svcList) {
final String svcName = svc.name;
// If svcName starts with serviceNamePrefix, then both strings must either be equal
// or else the first subsequent character in svcName must be a digit.
// This guards against any future GeckoProcessType whose string representation shares
// a common prefix with another GeckoProcessType value.
if (svcName.startsWith(serviceNamePrefix)
&& (svcName.length() == serviceNamePrefix.length()
|| Character.isDigit(svcName.codePointAt(serviceNamePrefix.length())))) {
++result;
}
}
if (result <= 0) {
throw new RuntimeException("Could not count " + serviceNamePrefix + " services in manifest");
}
return result;
}
}