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Diffstat (limited to 'absl/status/status.h')
| -rw-r--r-- | absl/status/status.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/absl/status/status.h b/absl/status/status.h index 967e6064..42530621 100644 --- a/absl/status/status.h +++ b/absl/status/status.h @@ -24,24 +24,137 @@ namespace absl { ABSL_NAMESPACE_BEGIN +// Sometimes multiple error codes may apply. Services should return +// the most specific error code that applies. For example, prefer +// `kOutOfRange` over `kFailedPrecondition` if both codes apply. +// Similarly prefer `kNotFound` or `kAlreadyExists` over `kFailedPrecondition`. enum class StatusCode : int { + // Not an error; returned on success kOk = 0, + + // The operation was cancelled, typically by the caller. kCancelled = 1, + + // Unknown error. For example, errors raised by APIs that do not return + // enough error information may be converted to this error. kUnknown = 2, + + // The client specified an invalid argument. Note that this differs + // from `kFailedPrecondition`. `kInvalidArgument` indicates arguments + // that are problematic regardless of the state of the system + // (such as a malformed file name). kInvalidArgument = 3, + + // The deadline expired before the operation could complete. For operations + // that change the state of the 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, + + // Some requested entity (such as file or directory) was not found. + // + // Note to server developers: if a request is denied for an entire class + // of users, such as gradual feature rollout or undocumented whitelist, + // `kNotFound` may be used. If a request is denied for some users within + // a class of users, such as user-based access control, `kPermissionDenied` + // must be used. kNotFound = 5, + + // The entity that a client attempted to create (such as file or directory) + // already exists. kAlreadyExists = 6, + + // The caller does not have permission to execute the specified + // operation. `kPermissionDenied` must not be used for rejections + // caused by exhausting some resource (use `kResourceExhausted` + // instead for those errors). `kPermissionDenied` must not be + // used if the caller can not be identified (use `kUnauthenticated` + // instead for those errors). This error code does not imply the + // request is valid or the requested entity exists or satisfies + // other pre-conditions. kPermissionDenied = 7, + + // Some resource has been exhausted, perhaps a per-user quota, or + // perhaps the entire file system is out of space. kResourceExhausted = 8, + + // The operation was rejected because the system is not in a state + // required for the operation's execution. For example, the directory + // to be deleted is non-empty, an rmdir operation is applied to + // a non-directory, etc. + // + // A litmus test 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-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, + + // The operation was aborted, typically due to a concurrency issue such as + // a sequencer check failure or transaction abort. + // + // See litmus test above for deciding between `kFailedPrecondition`, + // `kAborted`, and `kUnavailable`. kAborted = 10, + + // The operation was attempted past the valid range, such as seeking or + // reading past 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, + + // The operation is not implemented or is not supported/enabled in this + // service. kUnimplemented = 12, + + // Internal errors. This means that some invariants expected by the + // underlying system have been broken. This error code is reserved + // for serious errors. kInternal = 13, + + // The service is currently unavailable. This is most likely a + // transient condition, which can be corrected by retrying with + // a backoff. Note that it is not always safe to retry + // non-idempotent operations. + // + // See litmus test above for deciding between `kFailedPrecondition`, + // `kAborted`, and `kUnavailable`. kUnavailable = 14, + + // Unrecoverable data loss or corruption. kDataLoss = 15, + + // The request does not have valid authentication credentials for the + // operation. kUnauthenticated = 16, + + // An extra enum entry to prevent people from writing code that + // fails to compile when a new code is added. + // + // Nobody should ever reference this enumeration entry. In particular, + // if you write C++ code that switches on this enumeration, add a default: + // case instead of a case that mentions this enumeration entry. + // + // Nobody should rely on the value (currently 20) listed here. It + // may change in the future. kDoNotUseReservedForFutureExpansionUseDefaultInSwitchInstead_ = 20 }; |