OMS: include idmap data in dump

Teach the overlay manager to ask the idmap service to pretty print the
contents of each idmap file as part of OMS dump. This creates a single
entry point for dumping both OMS and idmap data, and circumvents the
problem of accessing the idmap service if it has been killed due to
inactivity.

Example idmap section:

---- 8< ----
IDMAP OF com.android.theme.color.sand
Paths:
    target path  : /system/framework/framework-res.apk
    overlay path : /product/overlay/AccentColorSand/AccentColorSandOverlay.apk
Debug info:
    W failed to find resource 'string/accent_color_overlay'
Mapping:
    0x0106006e -> 0x7f010000 (color/accent_device_default_dark -> color/accent_device_default_dark)
    0x01060070 -> 0x7f010001 (color/accent_device_default_light -> color/accent_device_default_light)
---- >8 ----

Bug: 189963636
Test: adb exec-out dumpsys
Test: adb exec-out cmd overlay dump
Test: adb exec-out cmd overlay dump <overlay-identifier>
Change-Id: I9de6ba646ad4714c9d0f0d8081fbf632577107e7

cmds/idmap2/idmap2d/Idmap2Service.cpp

@@ -33,6 +33,7 @@
 #include "idmap2/BinaryStreamVisitor.h"
 #include "idmap2/FileUtils.h"
 #include "idmap2/Idmap.h"
+#include "idmap2/PrettyPrintVisitor.h"
 #include "idmap2/Result.h"
 #include "idmap2/SysTrace.h"
 
@@ -45,6 +46,7 @@ using android::idmap2::FabricatedOverlayContainer;
 using android::idmap2::Idmap;
 using android::idmap2::IdmapHeader;
 using android::idmap2::OverlayResourceContainer;
+using android::idmap2::PrettyPrintVisitor;
 using android::idmap2::TargetResourceContainer;
 using android::idmap2::utils::kIdmapCacheDir;
 using android::idmap2::utils::kIdmapFilePermissionMask;
@@ -352,4 +354,24 @@ binder::Status Idmap2Service::deleteFabricatedOverlay(const std::string& overlay
   return ok();
 }
 
+binder::Status Idmap2Service::dumpIdmap(const std::string& overlay_path,
+                                        std::string* _aidl_return) {
+  assert(_aidl_return);
+
+  const auto idmap_path = Idmap::CanonicalIdmapPathFor(kIdmapCacheDir, overlay_path);
+  std::ifstream fin(idmap_path);
+  const auto idmap = Idmap::FromBinaryStream(fin);
+  fin.close();
+  if (!idmap) {
+    return error(idmap.GetErrorMessage());
+  }
+
+  std::stringstream stream;
+  PrettyPrintVisitor visitor(stream);
+  (*idmap)->accept(&visitor);
+  *_aidl_return = stream.str();
+
+  return ok();
+}
+
 }  // namespace android::os

cmds/idmap2/idmap2d/Idmap2Service.h

@@ -60,6 +60,8 @@ class Idmap2Service : public BinderService<Idmap2Service>, public BnIdmap2 {
   binder::Status getFabricatedOverlayInfos(
       std::vector<os::FabricatedOverlayInfo>* _aidl_return) override;
 
+  binder::Status dumpIdmap(const std::string& overlay_path, std::string* _aidl_return) override;
+
  private:
   // idmap2d is killed after a period of inactivity, so any information stored on this class should
   // be able to be recalculated if idmap2 dies and restarts.

cmds/idmap2/idmap2d/aidl/services/android/os/IIdmap2.aidl

@@ -16,8 +16,8 @@
 
 package android.os;
 
-import android.os.FabricatedOverlayInternal;
 import android.os.FabricatedOverlayInfo;
+import android.os.FabricatedOverlayInternal;
 
 /**
  * @hide
@@ -40,4 +40,5 @@ interface IIdmap2 {
   @nullable FabricatedOverlayInfo createFabricatedOverlay(in FabricatedOverlayInternal overlay);
   List<FabricatedOverlayInfo> getFabricatedOverlayInfos();
   boolean deleteFabricatedOverlay(@utf8InCpp String path);
+  @utf8InCpp String dumpIdmap(@utf8InCpp String overlayApkPath);
 }

services/core/java/com/android/server/om/IdmapDaemon.java

@@ -170,6 +170,16 @@ class IdmapDaemon {
         }
     }
 
+    String dumpIdmap(@NonNull String overlayPath) {
+        try (Connection c = connect()) {
+            String dump = mService.dumpIdmap(overlayPath);
+            return TextUtils.nullIfEmpty(dump);
+        } catch (Exception e) {
+            Slog.wtf(TAG, "failed to dump idmap", e);
+            return null;
+        }
+    }
+
     private IBinder getIdmapService() throws TimeoutException, RemoteException {
         SystemService.start(IDMAP_DAEMON);
 

services/core/java/com/android/server/om/IdmapManager.java

@@ -22,7 +22,6 @@ import static com.android.server.om.OverlayManagerService.TAG;
 import android.annotation.NonNull;
 import android.content.om.OverlayInfo;
 import android.content.om.OverlayableInfo;
-import android.content.pm.PackageParser;
 import android.os.Build.VERSION_CODES;
 import android.os.FabricatedOverlayInfo;
 import android.os.FabricatedOverlayInternal;
@@ -141,6 +140,14 @@ final class IdmapManager {
         return mIdmapDaemon.deleteFabricatedOverlay(path);
     }
 
+    /**
+     * Gets the idmap data associated with an overlay, in dump format.
+     * Only indented for debugging.
+     */
+    String dumpIdmap(@NonNull String overlayPath) {
+        return mIdmapDaemon.dumpIdmap(overlayPath);
+    }
+
     /**
      * Checks if overlayable and policies should be enforced on the specified overlay for backwards
      * compatibility with pre-Q overlays.

services/core/java/com/android/server/om/OverlayManagerServiceImpl.java

@@ -22,6 +22,7 @@ import static android.content.om.OverlayInfo.STATE_MISSING_TARGET;
 import static android.content.om.OverlayInfo.STATE_NO_IDMAP;
 import static android.content.om.OverlayInfo.STATE_OVERLAY_IS_BEING_REPLACED;
 import static android.content.om.OverlayInfo.STATE_TARGET_IS_BEING_REPLACED;
+import static android.os.UserHandle.USER_SYSTEM;
 
 import static com.android.server.om.OverlayManagerService.DEBUG;
 import static com.android.server.om.OverlayManagerService.TAG;
@@ -38,6 +39,7 @@ import android.os.FabricatedOverlayInternal;
 import android.text.TextUtils;
 import android.util.ArrayMap;
 import android.util.ArraySet;
+import android.util.Pair;
 import android.util.Slog;
 
 import com.android.internal.content.om.OverlayConfig;
@@ -682,8 +684,38 @@ final class OverlayManagerServiceImpl {
     }
 
     void dump(@NonNull final PrintWriter pw, @NonNull DumpState dumpState) {
+        Pair<OverlayIdentifier, String> overlayIdmap = null;
+        if (dumpState.getPackageName() != null) {
+            OverlayIdentifier id = new OverlayIdentifier(dumpState.getPackageName(),
+                    dumpState.getOverlayName());
+            OverlayInfo oi = mSettings.getNullableOverlayInfo(id, USER_SYSTEM);
+            if (oi != null) {
+                overlayIdmap = new Pair<>(id, oi.baseCodePath);
+            }
+        }
+
+        // settings
         mSettings.dump(pw, dumpState);
-        if (dumpState.getPackageName() == null) {
+
+        // idmap data
+        if (dumpState.getField() == null) {
+            Set<Pair<OverlayIdentifier, String>> allIdmaps = (overlayIdmap != null)
+                    ? Set.of(overlayIdmap) : mSettings.getAllIdentifiersAndBaseCodePaths();
+            for (Pair<OverlayIdentifier, String> pair : allIdmaps) {
+                pw.println("IDMAP OF " + pair.first);
+                String dump = mIdmapManager.dumpIdmap(pair.second);
+                if (dump != null) {
+                    pw.println(dump);
+                } else {
+                    OverlayInfo oi = mSettings.getNullableOverlayInfo(pair.first, USER_SYSTEM);
+                    pw.println((oi != null && !mIdmapManager.idmapExists(oi))
+                            ? "<missing idmap>" : "<internal error>");
+                }
+            }
+        }
+
+        // default overlays
+        if (overlayIdmap == null) {
             pw.println("Default overlays: " + TextUtils.join(";", mDefaultOverlays));
         }
     }

services/core/java/com/android/server/om/OverlayManagerSettings.java

@@ -26,6 +26,7 @@ import android.content.om.OverlayInfo;
 import android.os.UserHandle;
 import android.util.ArrayMap;
 import android.util.ArraySet;
+import android.util.Pair;
 import android.util.Slog;
 import android.util.TypedXmlPullParser;
 import android.util.TypedXmlSerializer;
@@ -205,6 +206,12 @@ final class OverlayManagerSettings {
         return paths;
     }
 
+    Set<Pair<OverlayIdentifier, String>> getAllIdentifiersAndBaseCodePaths() {
+        final Set<Pair<OverlayIdentifier, String>> set = new ArraySet<>();
+        mItems.forEach(item -> set.add(new Pair(item.mOverlay, item.mBaseCodePath)));
+        return set;
+    }
+
     @NonNull
     List<OverlayInfo> removeIf(@NonNull final Predicate<OverlayInfo> predicate, final int userId) {
         return removeIf(info -> (predicate.test(info) && info.userId == userId));