From 39c12039cbd44edba5911807e4c0ec30be264c05 Mon Sep 17 00:00:00 2001
From: Alex Dale <sigquit@google.com>
Date: Tue, 5 Nov 2024 14:40:42 -0800
Subject: [PATCH] Patch Android FileSystem::List for non-existing directory.

[ Merge of http://go/wvgerrit/210651 ]

The Android FileSystem implementation for List() would return an error
if the directory does not exist.  This creates an issue for the case
where the CDM attempts to list offline licenses after clearing all
data.  This typically won't effect a regular user, it causes
integration tests which re-provision to fail.

Bug: 372105842
Test: file_store_unittest on Oriole
Change-Id: I121b52ab95e36249ae5b196e987bc950a278131f
---
 libwvdrmengine/cdm/util/src/file_store.cpp       | 16 +++++++++++++++-
 .../cdm/util/test/file_store_unittest.cpp        | 11 +++++++++--
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/libwvdrmengine/cdm/util/src/file_store.cpp b/libwvdrmengine/cdm/util/src/file_store.cpp
index 63f3b716..4623fece 100644
--- a/libwvdrmengine/cdm/util/src/file_store.cpp
+++ b/libwvdrmengine/cdm/util/src/file_store.cpp
@@ -530,7 +530,21 @@ ssize_t FileSystem::FileSize(const std::string& file_name) {
 
 bool FileSystem::List(const std::string& path,
                       std::vector<std::string>* filenames) {
-  return FileUtils::List(GetFileNameForIdentifier(path, origin_), filenames);
+  if (filenames == nullptr) {
+    LOGE("Output |filenames| is null");
+    return false;
+  }
+  const std::string effective_path = GetFileNameForIdentifier(path, origin_);
+  int errno_value = 0;
+  if (FileUtils::Exists(effective_path, &errno_value)) {
+    return FileUtils::List(effective_path, filenames);
+  }
+  filenames->clear();
+  if (errno_value == 0 || errno_value == ENOENT) {
+    return true;
+  }
+  LOGE("Cannot list: errno = %d", errno_value);
+  return false;
 }
 
 void FileSystem::set_origin(const std::string& origin) { origin_ = origin; }
diff --git a/libwvdrmengine/cdm/util/test/file_store_unittest.cpp b/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
index ad30ac26..aaa86124 100644
--- a/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
+++ b/libwvdrmengine/cdm/util/test/file_store_unittest.cpp
@@ -265,10 +265,17 @@ TEST_F(FileTest, ListFiles) {
 }
 
 TEST_F(FileTest, ListFiles_NotAPath) {
-  const std::string not_path("zzz/xxx");
+  const std::string kTestFilename = "zzz.txt";
+  const std::string dir_path = wvcdm::test_vectors::kTestDir;
+  const std::string file_path = PathJoin(dir_path, kTestFilename);
+  std::unique_ptr<File> file =
+      file_system_.Open(file_path, FileSystem::kCreate);
+  ASSERT_TRUE(file) << "Failed to create file: " << kTestFilename;
+  file.reset();  // Close file
+
   std::vector<std::string> names;
   // Ask for non-existent path.
-  EXPECT_FALSE(file_system_.List(not_path, &names));
+  EXPECT_FALSE(file_system_.List(file_path, &names));
 }
 
 TEST_F(FileTest, ListFiles_NullParameter) {