Use raw pointer instead of shared_ptr
Throughout update_engine, there are many places we pass a shared_ptr of
FileDescriptor, for memory safety. But in many cases, functions only
need to use the pointer througout execution of the function, and do not
need to store these pointers. In these cases, it's perfectly safe to use
a raw pointer. Furthermore, the overuse of shared_ptr make life time of
FileDescriptors unpredictable. This is harmful in context of VABC, where
presence of a file descriptor can cause UnmapAllPartitions() to fail.
Therefore, we switch some of the safe usecases to raw pointer.
Test: th
Bug: 216391325
Change-Id: I3d986688e81fcc1d761b7f4926a3c81ac691788a
diff --git a/payload_consumer/verity_writer_android.cc b/payload_consumer/verity_writer_android.cc
index e2fab7d..b233b58 100644
--- a/payload_consumer/verity_writer_android.cc
+++ b/payload_consumer/verity_writer_android.cc
@@ -104,8 +104,8 @@
return true;
}
-bool VerityWriterAndroid::Finalize(FileDescriptorPtr read_fd,
- FileDescriptorPtr write_fd) {
+bool VerityWriterAndroid::Finalize(FileDescriptor* read_fd,
+ FileDescriptor* write_fd) {
const auto hash_tree_data_end =
partition_->hash_tree_data_offset + partition_->hash_tree_data_size;
if (total_offset_ < hash_tree_data_end) {
@@ -142,8 +142,8 @@
return true;
}
-bool VerityWriterAndroid::EncodeFEC(FileDescriptorPtr read_fd,
- FileDescriptorPtr write_fd,
+bool VerityWriterAndroid::EncodeFEC(FileDescriptor* read_fd,
+ FileDescriptor* write_fd,
uint64_t data_offset,
uint64_t data_size,
uint64_t fec_offset,
@@ -162,10 +162,6 @@
init_rs_char(FEC_PARAMS(fec_roots)), &free_rs_char);
TEST_AND_RETURN_FALSE(rs_char != nullptr);
- // Cache at most 1MB of fec data, in VABC, we need to re-open fd if we
- // perform a read() operation after write(). So reduce the number of writes
- // can save unnecessary re-opens.
- write_fd = std::make_shared<CachedFileDescriptor>(write_fd, 1 * (1 << 20));
for (size_t i = 0; i < rounds; i++) {
// Encodes |block_size| number of rs blocks each round so that we can read
// one block each time instead of 1 byte to increase random read
@@ -229,11 +225,10 @@
uint32_t fec_roots,
uint32_t block_size,
bool verify_mode) {
- FileDescriptorPtr fd(new EintrSafeFileDescriptor());
- TEST_AND_RETURN_FALSE(
- fd->Open(path.c_str(), verify_mode ? O_RDONLY : O_RDWR));
- return EncodeFEC(fd,
- fd,
+ EintrSafeFileDescriptor fd;
+ TEST_AND_RETURN_FALSE(fd.Open(path.c_str(), verify_mode ? O_RDONLY : O_RDWR));
+ return EncodeFEC(&fd,
+ &fd,
data_offset,
data_size,
fec_offset,