xref: /aosp_15_r20/external/grpc-grpc/src/core/lib/gprpp/posix/directory_reader.cc (revision cc02d7e222339f7a4f6ba5f422e6413f4bd931f2)
1 //
2 //
3 // Copyright 2023 gRPC authors.
4 //
5 // Licensed under the Apache License, Version 2.0 (the "License");
6 // you may not use this file except in compliance with the License.
7 // You may obtain a copy of the License at
8 //
9 //     http://www.apache.org/licenses/LICENSE-2.0
10 //
11 // Unless required by applicable law or agreed to in writing, software
12 // distributed under the License is distributed on an "AS IS" BASIS,
13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 // See the License for the specific language governing permissions and
15 // limitations under the License.
16 //
17 //
18 
19 #include <grpc/support/port_platform.h>
20 
21 #include <memory>
22 
23 #include "absl/functional/function_ref.h"
24 #include "absl/status/status.h"
25 #include "absl/strings/string_view.h"
26 
27 #if defined(GPR_LINUX) || defined(GPR_ANDROID) || defined(GPR_FREEBSD) || \
28     defined(GPR_APPLE)
29 
30 #include <dirent.h>
31 
32 #include <string>
33 
34 #include "src/core/lib/gprpp/directory_reader.h"
35 
36 namespace grpc_core {
37 
38 namespace {
39 const char kSkipEntriesSelf[] = ".";
40 const char kSkipEntriesParent[] = "..";
41 }  // namespace
42 
43 class DirectoryReaderImpl : public DirectoryReader {
44  public:
DirectoryReaderImpl(absl::string_view directory_path)45   explicit DirectoryReaderImpl(absl::string_view directory_path)
46       : directory_path_(directory_path) {}
Name() const47   absl::string_view Name() const override { return directory_path_; }
48   absl::Status ForEach(absl::FunctionRef<void(absl::string_view)>) override;
49 
50  private:
51   const std::string directory_path_;
52 };
53 
MakeDirectoryReader(absl::string_view filename)54 std::unique_ptr<DirectoryReader> MakeDirectoryReader(
55     absl::string_view filename) {
56   return std::make_unique<DirectoryReaderImpl>(filename);
57 }
58 
ForEach(absl::FunctionRef<void (absl::string_view)> callback)59 absl::Status DirectoryReaderImpl::ForEach(
60     absl::FunctionRef<void(absl::string_view)> callback) {
61   // Open the dir for reading
62   DIR* directory = opendir(directory_path_.c_str());
63   if (directory == nullptr) {
64     return absl::InternalError("Could not read crl directory.");
65   }
66   struct dirent* directory_entry;
67   // Iterate over everything in the directory
68   while ((directory_entry = readdir(directory)) != nullptr) {
69     const absl::string_view file_name = directory_entry->d_name;
70     // Skip "." and ".."
71     if (file_name == kSkipEntriesParent || file_name == kSkipEntriesSelf) {
72       continue;
73     }
74     // Call the callback with this filename
75     callback(file_name);
76   }
77   closedir(directory);
78   return absl::OkStatus();
79 }
80 }  // namespace grpc_core
81 
82 #endif  // GPR_LINUX || GPR_ANDROID || GPR_FREEBSD || GPR_APPLE
83