CDM FileIOTest: Explictly test corrupted file.

Since Write() takes two (or more) steps to finish, it's possible for
CdmFileIOImpl to be destructed after SetLength() is called but before
WriteFile() is called. In that case, since we SetLength(data_size), we
could end up with a corrupted file.

This CL update FileIOTest to explictly cover this case.

BUG=410630
TEST=ECKEncryptedMediaTest.FileIOTest still passes.

Review URL: https://codereview.chromium.org/563193002

Cr-Commit-Position: refs/heads/master@{#294867}

media/cdm/ppapi/cdm_file_io_test.cc

@@ -75,6 +75,10 @@ FileIOTestRunner::FileIOTestRunner(const CreateFileIOCB& create_file_io_cb)
   for (size_t i = 0; i < kLargeDataSize; ++i)
     large_data_[i] = i % kuint8max;
 
+  // Generate |corrupted_big_data_|.
+  corrupted_big_data_.assign(kData, kData + kDataSize);
+  corrupted_big_data_.resize(kBigDataSize, 0);
+
   AddTests();
 }
 
@@ -267,6 +271,36 @@ void FileIOTestRunner::AddTests() {
     CLOSE_FILE
   END_TEST_CASE
 
+  START_TEST_CASE("CloseDuringPendingOverwriteWithLargerData")
+    OPEN_FILE
+    EXPECT_FILE_OPENED(kSuccess)
+    WRITE_FILE(kData, kDataSize)
+    EXPECT_FILE_WRITTEN(kSuccess)
+    WRITE_FILE(kBigData, kBigDataSize)
+    CLOSE_FILE
+    // The file is corrupted. See http://crbug.com/410630
+    CREATE_FILE_IO
+    OPEN_FILE
+    EXPECT_FILE_OPENED(kSuccess)
+    READ_FILE
+    EXPECT_FILE_READ(kSuccess, &corrupted_big_data_[0], kBigDataSize)
+  END_TEST_CASE
+
+  START_TEST_CASE("CloseDuringPendingOverwriteWithSmallerData")
+    OPEN_FILE
+    EXPECT_FILE_OPENED(kSuccess)
+    WRITE_FILE(kBigData, kBigDataSize)
+    EXPECT_FILE_WRITTEN(kSuccess)
+    WRITE_FILE(kData, kDataSize)
+    CLOSE_FILE
+    // The file is corrupted. See http://crbug.com/410630
+    CREATE_FILE_IO
+    OPEN_FILE
+    EXPECT_FILE_OPENED(kSuccess)
+    READ_FILE
+    EXPECT_FILE_READ(kSuccess, kBigData, kDataSize)
+  END_TEST_CASE
+
   START_TEST_CASE("CloseDuringPendingRead")
     OPEN_FILE
     EXPECT_FILE_OPENED(kSuccess)
@@ -274,6 +308,12 @@ void FileIOTestRunner::AddTests() {
     EXPECT_FILE_WRITTEN(kSuccess)
     READ_FILE
     CLOSE_FILE
+    // Make sure the file is not modified.
+    CREATE_FILE_IO
+    OPEN_FILE
+    EXPECT_FILE_OPENED(kSuccess)
+    READ_FILE
+    EXPECT_FILE_READ(kSuccess, kData, kDataSize)
   END_TEST_CASE
 }
 

media/cdm/ppapi/cdm_file_io_test.h

@@ -146,6 +146,7 @@ class FileIOTestRunner {
   CompletionCB completion_cb_;
   std::list<FileIOTest> remaining_tests_;
   std::vector<uint8> large_data_;
+  std::vector<uint8> corrupted_big_data_;
   size_t total_num_tests_;  // Total number of tests.
   size_t num_passed_tests_;  // Number of passed tests.