YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you 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.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions 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.

//

#include "yb/util/errno.h"

#include <errno.h>

#include <string.h>

#include "yb/util/flag_tags.h"

#include "yb/util/status.h"

DEFINE_bool(suicide_on_eio, true,

            "Kill the process if an I/O operation results in EIO");

TAG_FLAG(suicide_on_eio, advanced);

namespace yb {

void ErrnoToCString(int err, char *buf, size_t buf_len) {

  CHECK_GT(buf_len, 0);

#if !defined(__GLIBC__) || \

  ((_POSIX_C_SOURCE >= 200112 || _XOPEN_SOURCE >= 600) && !defined(_GNU_SOURCE))

  // Using POSIX version 'int strerror_r(...)'.

  int ret = strerror_r(err, buf, buf_len);

  if (ret && ret != ERANGE && ret != EINVAL) {

    strncpy(buf, "unknown error", buf_len);

    buf[buf_len - 1] = '\0';

  }

#else

  // Using GLIBC version

  char* ret = strerror_r(err, buf, buf_len);

  if (ret != buf) {

    strncpy(buf, ret, buf_len);

    buf[buf_len - 1] = '\0';

  }

#endif

}

static const std::string kErrnoCategoryName = "system error";

static StatusCategoryRegisterer errno_category_registerer(

    StatusCategoryDescription::Make<ErrnoTag>(&kErrnoCategoryName));

namespace internal {

Status StatusFromErrno(const std::string& context, int err_number, const char* file, int line) {

  if (err_number == 0)

    return Status::OK();

  Errno err(err_number);

  switch (err_number) {

    case ENOENT:

      return Status(Status::kNotFound, file, line, context, err);

    case EEXIST:

      return Status(Status::kAlreadyPresent, file, line, context, err);

    case EOPNOTSUPP:

      return Status(Status::kNotSupported, file, line, context, err);

  }

  return Status(Status::kIOError, file, line, context, err);

}

// TODO: reconsider this approach to handling EIO.

Status StatusFromErrnoSpecialEioHandling(

    const std::string& context, int err_number, const char* file, int line) {

  if (err_number == EIO && FLAGS_suicide_on_eio) {

    // TODO: This is very, very coarse-grained. A more comprehensive

    // approach is described in KUDU-616.

    LOG(FATAL) << "Fatal I/O error, context: " << context;

  }

  return internal::StatusFromErrno(context, err_number, file, line);

}

// A lot of C library functions return zero on success and non-zero on failure, with the actual

// error code stored in errno. This helper constructs a Status based on errno but only if the return

// value (the rv parameter) is non-zero.

Status StatusFromErrnoIfNonZero(const std::string& context, int rv, const char* file, int line) {

  if (rv == 0)

    return Status::OK();

  decltype(errno) cached_errno = errno;

  if (cached_errno == 0) {

    return Status(

        Status::kIllegalState, file, line, Format("$0: return value is $1 but errno is zero",

        context, rv));

  }

  return StatusFromErrno(context, cached_errno, file, line);

}

}  // namespace internal

} // namespace yb