Delete external app dir on app uninstall with FUSE

installd parses /proc/mounts to determine the file path to use when
deleting app dirs on external storage. With FUSE mounts instead, these
/proc/mounts looks very different.

Now, we use the correct mounts on /mnt/pass_through when deleting dirs

Test: atest ExternalStorageHostTest#testExternalStorageClearing
Change-Id: Ic42574a46c4408ce5d43d4f412dce7f9876b8044
diff --git a/cmds/installd/InstalldNativeService.cpp b/cmds/installd/InstalldNativeService.cpp
index 4026f29..b23d69c 100644
--- a/cmds/installd/InstalldNativeService.cpp
+++ b/cmds/installd/InstalldNativeService.cpp
@@ -101,6 +101,7 @@
 static constexpr int kVerityPageSize = 4096;
 static constexpr size_t kSha256Size = 32;
 static constexpr const char* kPropApkVerityMode = "ro.apk_verity.mode";
+static constexpr const char* kFuseProp = "persist.sys.fuse";
 
 namespace {
 
@@ -592,12 +593,21 @@
         std::lock_guard<std::recursive_mutex> lock(mMountsLock);
         for (const auto& n : mStorageMounts) {
             auto extPath = n.second;
-            if (n.first.compare(0, 14, "/mnt/media_rw/") != 0) {
-                extPath += StringPrintf("/%d", userId);
-            } else if (userId != 0) {
-                // TODO: support devices mounted under secondary users
-                continue;
+
+            if (android::base::GetBoolProperty(kFuseProp, false)) {
+                std::regex re("^\\/mnt\\/pass_through\\/[0-9]+\\/emulated");
+                if (std::regex_match(extPath, re)) {
+                    extPath += "/" + std::to_string(userId);
+                }
+            } else {
+                if (n.first.compare(0, 14, "/mnt/media_rw/") != 0) {
+                    extPath += StringPrintf("/%d", userId);
+                } else if (userId != 0) {
+                    // TODO: support devices mounted under secondary users
+                    continue;
+                }
             }
+
             if (flags & FLAG_CLEAR_CACHE_ONLY) {
                 // Clear only cached data from shared storage
                 auto path = StringPrintf("%s/Android/data/%s/cache", extPath.c_str(), pkgname);
@@ -688,16 +698,26 @@
         std::lock_guard<std::recursive_mutex> lock(mMountsLock);
         for (const auto& n : mStorageMounts) {
             auto extPath = n.second;
-            if (n.first.compare(0, 14, "/mnt/media_rw/") != 0) {
-                extPath += StringPrintf("/%d", userId);
-            } else if (userId != 0) {
-                // TODO: support devices mounted under secondary users
-                continue;
+
+            if (android::base::GetBoolProperty(kFuseProp, false)) {
+                std::regex re("^\\/mnt\\/pass_through\\/[0-9]+\\/emulated");
+                if (std::regex_match(extPath, re)) {
+                    extPath += "/" + std::to_string(userId);
+                }
+            } else {
+                if (n.first.compare(0, 14, "/mnt/media_rw/") != 0) {
+                    extPath += StringPrintf("/%d", userId);
+                } else if (userId != 0) {
+                    // TODO: support devices mounted under secondary users
+                    continue;
+                }
             }
+
             auto path = StringPrintf("%s/Android/data/%s", extPath.c_str(), pkgname);
             if (delete_dir_contents_and_dir(path, true) != 0) {
                 res = error("Failed to delete contents of " + path);
             }
+
             path = StringPrintf("%s/Android/media/%s", extPath.c_str(), pkgname);
             if (delete_dir_contents_and_dir(path, true) != 0) {
                 res = error("Failed to delete contents of " + path);
@@ -2778,12 +2798,19 @@
         std::getline(in, target, ' ');
         std::getline(in, ignored);
 
+        if (android::base::GetBoolProperty(kFuseProp, false)) {
+            if (target.compare(0, 17, "/mnt/pass_through") == 0) {
+                LOG(DEBUG) << "Found storage mount " << source << " at " << target;
+                mStorageMounts[source] = target;
+            }
+        } else {
 #if !BYPASS_SDCARDFS
-        if (target.compare(0, 21, "/mnt/runtime/default/") == 0) {
-            LOG(DEBUG) << "Found storage mount " << source << " at " << target;
-            mStorageMounts[source] = target;
-        }
+            if (target.compare(0, 21, "/mnt/runtime/default/") == 0) {
+                LOG(DEBUG) << "Found storage mount " << source << " at " << target;
+                mStorageMounts[source] = target;
+            }
 #endif
+        }
     }
     return ok();
 }