authfs: refine/rename trait ReadOnlyDataByChunk
- ReadOnlyDataByChunk is renamed to ReadByChunk
- `fn read_chunk` now takes a fixed-size array of chunk size
- Behavior change:
1. Reading beyond file size now should not crash, and should return 0.
2. `read_chunk` should return a full chunk unless it's the last
(wasn't clearly defined previously).
Bug: 181674212
Bug: 182173887
Test: atest
Change-Id: I7017b5ed986d0bfc594da58a1ed9f59ac555643e
diff --git a/authfs/src/file/remote_file.rs b/authfs/src/file/remote_file.rs
index dbf6bd9..f2ac23f 100644
--- a/authfs/src/file/remote_file.rs
+++ b/authfs/src/file/remote_file.rs
@@ -14,12 +14,12 @@
* limitations under the License.
*/
+use std::cmp::min;
use std::convert::TryFrom;
use std::io;
-use std::io::Write;
use std::sync::{Arc, Mutex};
-use super::{RandomWrite, ReadOnlyDataByChunk};
+use super::{ChunkBuffer, RandomWrite, ReadByChunk};
use crate::common::CHUNK_SIZE;
use authfs_aidl_interface::aidl::com::android::virt::fs::IVirtFdService;
@@ -31,7 +31,7 @@
service: &Arc<Mutex<VirtFdService>>,
remote_fd: i32,
chunk_index: u64,
- mut buf: &mut [u8],
+ buf: &mut ChunkBuffer,
) -> io::Result<usize> {
let offset = i64::try_from(chunk_index * CHUNK_SIZE)
.map_err(|_| io::Error::from_raw_os_error(libc::EOVERFLOW))?;
@@ -41,7 +41,8 @@
.unwrap()
.readFile(remote_fd, offset, buf.len() as i32)
.map_err(|e| io::Error::new(io::ErrorKind::Other, e.get_description()))?;
- buf.write(&chunk)
+ buf.copy_from_slice(&chunk);
+ Ok(min(buf.len(), chunk.len()))
}
pub struct RemoteFileReader {
@@ -56,8 +57,8 @@
}
}
-impl ReadOnlyDataByChunk for RemoteFileReader {
- fn read_chunk(&self, chunk_index: u64, buf: &mut [u8]) -> io::Result<usize> {
+impl ReadByChunk for RemoteFileReader {
+ fn read_chunk(&self, chunk_index: u64, buf: &mut ChunkBuffer) -> io::Result<usize> {
remote_read_chunk(&self.service, self.file_fd, chunk_index, buf)
}
}
@@ -75,8 +76,8 @@
}
}
-impl ReadOnlyDataByChunk for RemoteMerkleTreeReader {
- fn read_chunk(&self, chunk_index: u64, mut buf: &mut [u8]) -> io::Result<usize> {
+impl ReadByChunk for RemoteMerkleTreeReader {
+ fn read_chunk(&self, chunk_index: u64, buf: &mut ChunkBuffer) -> io::Result<usize> {
let offset = i64::try_from(chunk_index * CHUNK_SIZE)
.map_err(|_| io::Error::from_raw_os_error(libc::EOVERFLOW))?;
@@ -86,7 +87,8 @@
.unwrap()
.readFsverityMerkleTree(self.file_fd, offset, buf.len() as i32)
.map_err(|e| io::Error::new(io::ErrorKind::Other, e.get_description()))?;
- buf.write(&chunk)
+ buf.copy_from_slice(&chunk);
+ Ok(min(buf.len(), chunk.len()))
}
}
@@ -116,8 +118,8 @@
}
}
-impl ReadOnlyDataByChunk for RemoteFileEditor {
- fn read_chunk(&self, chunk_index: u64, buf: &mut [u8]) -> io::Result<usize> {
+impl ReadByChunk for RemoteFileEditor {
+ fn read_chunk(&self, chunk_index: u64, buf: &mut ChunkBuffer) -> io::Result<usize> {
remote_read_chunk(&self.service, self.file_fd, chunk_index, buf)
}
}