absl_status.h

// Copyright lowRISC contributors (OpenTitan project).
// Licensed under the Apache License, Version 2.0, see LICENSE for details.
// SPDX-License-Identifier: Apache-2.0
 
#ifndef OPENTITAN_SW_DEVICE_LIB_CRYPTO_INCLUDE_FREESTANDING_ABSL_STATUS_H_
#define OPENTITAN_SW_DEVICE_LIB_CRYPTO_INCLUDE_FREESTANDING_ABSL_STATUS_H_
 
// Note: the status definitions were taken directly from the abseil-cpp
// library, and in particular from the file:
// https://github.com/abseil/abseil-cpp/blob/master/absl/status/status.h
// The copyright is preserved below:
// -----------------------------------------------------------------------------
// Copyright 2019 The Abseil 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.
// -----------------------------------------------------------------------------
 
#ifdef __cplusplus
extern "C" {
#endif
 
/**
 * This enum was taken directly from the abseil-cpp library:
 * https://github.com/abseil/abseil-cpp/blob/master/absl/status/status.h
 *
 * These error codes serve as general error classifications which are used to
 * build up more specific error codes.
 *
 * DO NOT USE THESE CODES DIRECTLY. Use these codes to build per-module error
 * codes in error.h.  Although these error codes are generally used at
 * Google by RPC servers, the advice about how to use them and how to
 * categorize errors is generally sound.
 */
typedef enum absl_status_code {
  // StatusCode::kOk
  //
  // kOK (gRPC code "OK") does not indicate an error; this value is returned on
  // success. It is typical to check for this value before proceeding on any
  // given call across an API or RPC boundary. To check this value, use the
  // `absl::Status::ok()` member function rather than inspecting the raw code.
  kOk = 0,
 
  // StatusCode::kCancelled
  //
  // kCancelled (gRPC code "CANCELLED") indicates the operation was cancelled,
  // typically by the caller.
  kCancelled = 1,
 
  // StatusCode::kUnknown
  //
  // kUnknown (gRPC code "UNKNOWN") indicates an unknown error occurred. In
  // general, more specific errors should be raised, if possible. Errors raised
  // by APIs that do not return enough error information may be converted to
  // this error.
  kUnknown = 2,
 
  // StatusCode::kInvalidArgument
  //
  // kInvalidArgument (gRPC code "INVALID_ARGUMENT") indicates the caller
  // specified an invalid argument, such a malformed filename. Note that such
  // errors should be narrowly limited to indicate to the invalid nature of the
  // arguments themselves. Errors with validly formed arguments that may cause
  // errors with the state of the receiving system should be denoted with
  // `kFailedPrecondition` instead.
  kInvalidArgument = 3,
 
  // StatusCode::kDeadlineExceeded
  //
  // kDeadlineExceeded (gRPC code "DEADLINE_EXCEEDED") indicates a deadline
  // expired before the operation could complete. For operations that may change
  // state within a system, this error may be returned even if the operation has
  // completed successfully. For example, a successful response from a server
  // could have been delayed long enough for the deadline to expire.
  kDeadlineExceeded = 4,
 
  // StatusCode::kNotFound
  //
  // kNotFound (gRPC code "NOT_FOUND") indicates some requested entity (such as
  // a file or directory) was not found.
  //
  // `kNotFound` is useful if a request should be denied for an entire class of
  // users, such as during a gradual feature rollout or undocumented allow list.
  // If, instead, a request should be denied for specific sets of users, such as
  // through user-based access control, use `kPermissionDenied` instead.
  kNotFound = 5,
 
  // StatusCode::kAlreadyExists
  //
  // kAlreadyExists (gRPC code "ALREADY_EXISTS") indicates the entity that a
  // caller attempted to create (such as file or directory) is already present.
  kAlreadyExists = 6,
 
  // StatusCode::kPermissionDenied
  //
  // kPermissionDenied (gRPC code "PERMISSION_DENIED") indicates that the caller
  // does not have permission to execute the specified operation. Note that this
  // error is different than an error due to an *un*authenticated user. This
  // error code does not imply the request is valid or the requested entity
  // exists or satisfies any other pre-conditions.
  //
  // `kPermissionDenied` must not be used for rejections caused by exhausting
  // some resource. Instead, use `kResourceExhausted` for those errors.
  // `kPermissionDenied` must not be used if the caller cannot be identified.
  // Instead, use `kUnauthenticated` for those errors.
  kPermissionDenied = 7,
 
  // StatusCode::kResourceExhausted
  //
  // kResourceExhausted (gRPC code "RESOURCE_EXHAUSTED") indicates some resource
  // has been exhausted, perhaps a per-user quota, or perhaps the entire file
  // system is out of space.
  kResourceExhausted = 8,
 
  // StatusCode::kFailedPrecondition
  //
  // kFailedPrecondition (gRPC code "FAILED_PRECONDITION") indicates that the
  // operation was rejected because the system is not in a state required for
  // the operation's execution. For example, a directory to be deleted may be
  // non-empty, an "rmdir" operation is applied to a non-directory, etc.
  //
  // Some guidelines that may help a service implementer in deciding between
  // `kFailedPrecondition`, `kAborted`, and `kUnavailable`:
  //
  //  (a) Use `kUnavailable` if the client can retry just the failing call.
  //  (b) Use `kAborted` if the client should retry at a higher transaction
  //      level (such as when a client-specified test-and-set fails, indicating
  //      the client should restart a read-modify-write sequence).
  //  (c) Use `kFailedPrecondition` if the client should not retry until
  //      the system state has been explicitly fixed. For example, if an "rmdir"
  //      fails because the directory is non-empty, `kFailedPrecondition`
  //      should be returned since the client should not retry unless
  //      the files are deleted from the directory.
  kFailedPrecondition = 9,
 
  // StatusCode::kAborted
  //
  // kAborted (gRPC code "ABORTED") indicates the operation was aborted,
  // typically due to a concurrency issue such as a sequencer check failure or a
  // failed transaction.
  //
  // See the guidelines above for deciding between `kFailedPrecondition`,
  // `kAborted`, and `kUnavailable`.
  kAborted = 10,
 
  // StatusCode::kOutOfRange
  //
  // kOutOfRange (gRPC code "OUT_OF_RANGE") indicates the operation was
  // attempted past the valid range, such as seeking or reading past an
  // end-of-file.
  //
  // Unlike `kInvalidArgument`, this error indicates a problem that may
  // be fixed if the system state changes. For example, a 32-bit file
  // system will generate `kInvalidArgument` if asked to read at an
  // offset that is not in the range [0,2^32-1], but it will generate
  // `kOutOfRange` if asked to read from an offset past the current
  // file size.
  //
  // There is a fair bit of overlap between `kFailedPrecondition` and
  // `kOutOfRange`.  We recommend using `kOutOfRange` (the more specific
  // error) when it applies so that callers who are iterating through
  // a space can easily look for an `kOutOfRange` error to detect when
  // they are done.
  kOutOfRange = 11,
 
  // StatusCode::kUnimplemented
  //
  // kUnimplemented (gRPC code "UNIMPLEMENTED") indicates the operation is not
  // implemented or supported in this service. In this case, the operation
  // should not be re-attempted.
  kUnimplemented = 12,
 
  // StatusCode::kInternal
  //
  // kInternal (gRPC code "INTERNAL") indicates an internal error has occurred
  // and some invariants expected by the underlying system have not been
  // satisfied. This error code is reserved for serious errors.
  kInternal = 13,
 
  // StatusCode::kUnavailable
  //
  // kUnavailable (gRPC code "UNAVAILABLE") indicates the service is currently
  // unavailable and that this is most likely a transient condition. An error
  // such as this can be corrected by retrying with a backoff scheme. Note that
  // it is not always safe to retry non-idempotent operations.
  //
  // See the guidelines above for deciding between `kFailedPrecondition`,
  // `kAborted`, and `kUnavailable`.
  kUnavailable = 14,
 
  // StatusCode::kDataLoss
  //
  // kDataLoss (gRPC code "DATA_LOSS") indicates that unrecoverable data loss or
  // corruption has occurred. As this error is serious, proper alerting should
  // be attached to errors such as this.
  kDataLoss = 15,
 
  // StatusCode::kUnauthenticated
  //
  // kUnauthenticated (gRPC code "UNAUTHENTICATED") indicates that the request
  // does not have valid authentication credentials for the operation. Correct
  // the authentication and try again.
  kUnauthenticated = 16,
 
  // StatusCode::DoNotUseReservedForFutureExpansionUseDefaultInSwitchInstead_
  //
  // NOTE: this error code entry should not be used and you should not rely on
  // its value, which may change.
  //
  // The purpose of this enumerated value is to force people who handle status
  // codes with `switch()` statements to *not* simply enumerate all possible
  // values, but instead provide a "default:" case. Providing such a default
  // case ensures that code will compile when new codes are added.
  kDoNotUseReservedForFutureExpansionUseDefaultInSwitchInstead_ = 20
} absl_status_t;
 
#ifdef __cplusplus
}
#endif
 
#endif  // OPENTITAN_SW_DEVICE_LIB_CRYPTO_INCLUDE_FREESTANDING_ABSL_STATUS_H_