xref: /aosp_15_r20/external/sandboxed-api/sandboxed_api/embed_file.h (revision ec63e07ab9515d95e79c211197c445ef84cefa6a)
1 // Copyright 2019 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef SANDBOXED_API_EMBED_FILE_H_
16 #define SANDBOXED_API_EMBED_FILE_H_
17 
18 #include "sandboxed_api/file_toc.h"
19 #include "absl/base/thread_annotations.h"
20 #include "absl/container/flat_hash_map.h"
21 #include "absl/synchronization/mutex.h"
22 
23 namespace sapi {
24 
25 // The class provides primitives for converting FileToc structures into
26 // executable files.
27 class EmbedFile {
28  public:
29   EmbedFile(const EmbedFile&) = delete;
30   EmbedFile& operator=(const EmbedFile&) = delete;
31 
32   // Returns the pointer to the per-process EmbedFile object.
33   static EmbedFile* instance();
34 
35   // Returns a file-descriptor for a given FileToc.
36   int GetFdForFileToc(const FileToc* toc);
37 
38   // Returns a duplicated file-descriptor for a given FileToc.
39   int GetDupFdForFileToc(const FileToc* toc);
40 
41  private:
42   // Creates an executable file for a given FileToc, and return its
43   // file-descriptors (-1 in case of errors).
44   static int CreateFdForFileToc(const FileToc* toc);
45 
46   EmbedFile() = default;
47 
48   // List of File TOCs and corresponding file-descriptors.
49   absl::flat_hash_map<const FileToc*, int> file_tocs_
50       ABSL_GUARDED_BY(file_tocs_mutex_);
51   absl::Mutex file_tocs_mutex_;
52 };
53 
54 }  // namespace sapi
55 
56 #endif  // SANDBOXED_API_EMBED_FILE_H_
57