YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

// Copyright (c) YugaByte, Inc.

//

// 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

//

// http://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.

#ifndef YB_UTIL_FILE_UTIL_H

#define YB_UTIL_FILE_UTIL_H

#include <float.h>

#include <string.h>

#include <chrono>

#include <cstdarg>

#include <sstream>

#include <string>

#include <type_traits>

#include <boost/mpl/and.hpp>

#include "yb/util/status_fwd.h"

#include "yb/util/env.h"

#include "yb/util/env_util.h"

#include "yb/util/faststring.h"

#include "yb/util/format.h"

#include "yb/util/path_util.h"

#include "yb/util/tostring.h"

#include "yb/util/type_traits.h"

namespace yb {

YB_STRONGLY_TYPED_BOOL(CreateIfMissing);

YB_STRONGLY_TYPED_BOOL(UseHardLinks);

// TODO(unify_env): Temporary workaround until Env/Files from rocksdb and yb are unified

// (https://github.com/yugabyte/yugabyte-db/issues/1661).

// Following function returns OK if the file at `path` exists.

// NotFound if the named file does not exist, the calling process does not have permission to

//          determine whether this file exists, or if the path is invalid.

// IOError if an IO Error was encountered.

// Uses specified `env` environment implementation to do the actual file existence checking.

inline CHECKED_STATUS CheckFileExistsResult(const Status& status) {

  return status;

}

inline CHECKED_STATUS CheckFileExistsResult(bool exists) {

  return exists ? Status::OK() : STATUS(NotFound, "");

}

template <class Env>

inline CHECKED_STATUS FileExists(Env* env, const std::string& path) {

  return CheckFileExistsResult(env->FileExists(path));

}

using yb::env_util::CopyFile;

// Copies directory from `src_dir` to `dest_dir` using `env`.

// use_hard_links specifies whether to create hard links instead of actual file copying.

// create_if_missing specifies whether to create dest dir if doesn't exist or return an error.

// Returns error status in case of I/O errors.

template <class TEnv>

CHECKED_STATUS CopyDirectory(

    TEnv* env, const string& src_dir, const string& dest_dir, UseHardLinks use_hard_links,

    CreateIfMissing create_if_missing) {

  RETURN_NOT_OK_PREPEND(

      FileExists(env, src_dir), Format("Source directory does not exist: $0", src_dir));

  Status s = FileExists(env, dest_dir);

  if (!s.ok()) {

    if (create_if_missing) {

      RETURN_NOT_OK_PREPEND(

          env->CreateDir(dest_dir), Format("Cannot create destination directory: $0", dest_dir));

    } else {

      return s.CloneAndPrepend(Format("Destination directory does not exist: $0", dest_dir));

    }

  }

  // Copy files.

  std::vector<string> files;

  RETURN_NOT_OK_PREPEND(

      env->GetChildren(src_dir, &files),

      Format("Cannot get list of files for directory: $0", src_dir));

  for (const string& file : files) {

    if (file != "." && file != "..") {

      const auto src_path = JoinPathSegments(src_dir, file);

      const auto dest_path = JoinPathSegments(dest_dir, file);

      if (use_hard_links) {

        s = env->LinkFile(src_path, dest_path);

        if (s.ok()) {

          continue;

        }

      }

      if (env->DirExists(src_path)) {

        RETURN_NOT_OK_PREPEND(

            CopyDirectory(env, src_path, dest_path, use_hard_links, CreateIfMissing::kTrue),

            Format("Cannot copy directory: $0", src_path));

      } else {

        RETURN_NOT_OK_PREPEND(

            CopyFile(env, src_path, dest_path), Format("Cannot copy file: $0", src_path));

      }

    }

  }

  return Status::OK();

}

}  // namespace yb

#endif  // YB_UTIL_FILE_UTIL_H