blob: 76d2fc892f048daf8eb3bac1f4bdc2de00f8bc08 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
// Copyright 2021 The Pigweed Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not
// use this file except in compliance with the License. You may obtain a copy of
// the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations under
// the License.
#include "pw_blob_store/flat_file_system_entry.h"
#include <cstddef>
#include <mutex>
#include "pw_assert/check.h"
#include "pw_blob_store/blob_store.h"
#include "pw_file/flat_file_system.h"
#include "pw_span/span.h"
#include "pw_status/status.h"
#include "pw_status/status_with_size.h"
#include "pw_sync/virtual_basic_lockable.h"
namespace pw::blob_store {
Status FlatFileSystemBlobStoreEntry::Init() {
std::lock_guard lock(blob_store_lock_);
if (initialized_) {
return OkStatus();
}
const Status status = blob_store_.Init();
initialized_ = status.ok();
return status;
}
void FlatFileSystemBlobStoreEntry::EnsureInitialized() {
{ // Only hold lock for initial check so Init() doesn't recursively lock.
std::lock_guard lock(blob_store_lock_);
if (initialized_) {
return;
}
}
// Don't inline the Init() into the DCHECK() as disabling the DCHECK()
// statement would disable the Init() call as well.
const Status status = Init();
PW_DCHECK_OK(status);
}
StatusWithSize FlatFileSystemBlobStoreEntry::Name(span<char> dest) {
EnsureInitialized();
std::lock_guard lock(blob_store_lock_);
BlobStore::BlobReader reader(blob_store_);
if (const Status status = reader.Open(); !status.ok()) {
// When a BlobStore is empty, Open() reports FAILED_PRECONDITION. The
// FlatFileSystemService expects NOT_FOUND when a file is not present at the
// entry.
if (status.IsFailedPrecondition()) {
return StatusWithSize(Status::NotFound(), 0);
} else if (status.IsUnavailable()) {
return StatusWithSize(Status::Unavailable(), 0);
} else {
return StatusWithSize(Status::Internal(), 0);
}
}
return reader.GetFileName(dest);
}
size_t FlatFileSystemBlobStoreEntry::SizeBytes() {
EnsureInitialized();
std::lock_guard lock(blob_store_lock_);
BlobStore::BlobReader reader(blob_store_);
if (!reader.Open().ok()) {
return 0;
}
return reader.ConservativeReadLimit();
}
// TODO(pwbug/488): This file can be deleted even though it is read-only.
// This type of behavior should be possible to express via the FileSystem RPC
// service.
Status FlatFileSystemBlobStoreEntry::Delete() {
EnsureInitialized();
std::lock_guard lock(blob_store_lock_);
BlobStore::BlobWriterWithBuffer blob_writer(blob_store_);
PW_TRY(blob_writer.Open());
return blob_writer.Discard();
}
} // namespace pw::blob_store
|
