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// 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
//
//
// 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.
//
// -----------------------------------------------------------------------------
// File: status.h
// -----------------------------------------------------------------------------
//
// This header file defines the Abseil `status` library, consisting of:
//
// * An `absl::Status` class for holding error handling information
// * A set of canonical `absl::StatusCode` error codes, and associated
// utilities for generating and propagating status codes.
// * A set of helper functions for creating status codes and checking their
// values
//
// Within Google, `absl::Status` is the primary mechanism for communicating
// errors in C++, and is used to represent error state in both in-process
// library calls as well as RPC calls. Some of these errors may be recoverable,
// but others may not. Most functions that can produce a recoverable error
// should be designed to return an `absl::Status` (or `absl::StatusOr`).
//
// Example:
//
// absl::Status myFunction(absl::string_view fname, ...) {
// ...
// // encounter error
// if (error condition) {
// return absl::InvalidArgumentError("bad mode");
// }
// // else, return OK
// return absl::OkStatus();
// }
//
// An `absl::Status` is designed to either return "OK" or one of a number of
// different error codes, corresponding to typical error conditions.
// In almost all cases, when using `absl::Status` you should use the canonical
// error codes (of type `absl::StatusCode`) enumerated in this header file.
// These canonical codes are understood across the codebase and will be
// accepted across all API and RPC boundaries.
#ifndef ABSL_STATUS_STATUS_H_
#define ABSL_STATUS_STATUS_H_
#include <cassert>
#include <cstdint>
#include <ostream>
#include <string>
#include <utility>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/macros.h"
#include "absl/base/optimization.h"
#include "absl/functional/function_ref.h"
#include "absl/status/internal/status_internal.h"
#include "absl/strings/cord.h"
#include "absl/strings/string_view.h"
#include "absl/types/optional.h"
// TODO: danilchap - Remove include below when other third_party libraries
// stop silently rely on it.
#include "absl/strings/str_cat.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// absl::StatusCode
//
// An `absl::StatusCode` is an enumerated type indicating either no error ("OK")
// or an error condition. In most cases, an `absl::Status` indicates a
// recoverable error, and the purpose of signalling an error is to indicate what
// action to take in response to that error. These error codes map to the proto
//
// The errors listed below are the canonical errors associated with
// `absl::Status` and are used throughout the codebase. As a result, these
// error codes are somewhat generic.
//
// In general, try to return the most specific error that applies if more than
// one error may pertain. For example, prefer `kOutOfRange` over
// `kFailedPrecondition` if both codes apply. Similarly prefer `kNotFound` or
// `kAlreadyExists` over `kFailedPrecondition`.
//
// Because these errors may cross RPC boundaries, these codes are tied to the
// `google.rpc.Code` definitions within
// The string value of these RPC codes is denoted within each enum below.
//
// If your error handling code requires more context, you can attach payloads
// to your status. See `absl::Status::SetPayload()` and
// `absl::Status::GetPayload()` below.
enum class StatusCode : int {
// 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 as a malformed filename. Note that use
// of such errors should be narrowly limited to indicate 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 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 that the entity a
// caller attempted to create (such as a 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 a "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
};
// StatusCodeToString()
//
// Returns the name for the status code, or "" if it is an unknown value.
std::string StatusCodeToString(StatusCode code);
// operator<<
//
// Streams StatusCodeToString(code) to `os`.
std::ostream& operator<<(std::ostream& os, StatusCode code);
// absl::StatusToStringMode
//
// An `absl::StatusToStringMode` is an enumerated type indicating how
// `absl::Status::ToString()` should construct the output string for a non-ok
// status.
enum class StatusToStringMode : int {
// ToString will not contain any extra data (such as payloads). It will only
// contain the error code and message, if any.
kWithNoExtraData = 0,
// ToString will contain the payloads.
kWithPayload = 1 << 0,
// ToString will include all the extra data this Status has.
kWithEverything = ~kWithNoExtraData,
// Default mode used by ToString. Its exact value might change in the future.
kDefault = kWithPayload,
};
// absl::StatusToStringMode is specified as a bitmask type, which means the
// following operations must be provided:
inline constexpr StatusToStringMode operator&(StatusToStringMode lhs,
StatusToStringMode rhs) {
return static_cast<StatusToStringMode>(static_cast<int>(lhs) &
static_cast<int>(rhs));
}
inline constexpr StatusToStringMode operator|(StatusToStringMode lhs,
StatusToStringMode rhs) {
return static_cast<StatusToStringMode>(static_cast<int>(lhs) |
static_cast<int>(rhs));
}
inline constexpr StatusToStringMode operator^(StatusToStringMode lhs,
StatusToStringMode rhs) {
return static_cast<StatusToStringMode>(static_cast<int>(lhs) ^
static_cast<int>(rhs));
}
inline constexpr StatusToStringMode operator~(StatusToStringMode arg) {
return static_cast<StatusToStringMode>(~static_cast<int>(arg));
}
inline StatusToStringMode& operator&=(StatusToStringMode& lhs,
StatusToStringMode rhs) {
lhs = lhs & rhs;
return lhs;
}
inline StatusToStringMode& operator|=(StatusToStringMode& lhs,
StatusToStringMode rhs) {
lhs = lhs | rhs;
return lhs;
}
inline StatusToStringMode& operator^=(StatusToStringMode& lhs,
StatusToStringMode rhs) {
lhs = lhs ^ rhs;
return lhs;
}
// absl::Status
//
// The `absl::Status` class is generally used to gracefully handle errors
// across API boundaries (and in particular across RPC boundaries). Some of
// these errors may be recoverable, but others may not. Most
// functions which can produce a recoverable error should be designed to return
// either an `absl::Status` (or the similar `absl::StatusOr<T>`, which holds
// either an object of type `T` or an error).
//
// API developers should construct their functions to return `absl::OkStatus()`
// upon success, or an `absl::StatusCode` upon another type of error (e.g
// an `absl::StatusCode::kInvalidArgument` error). The API provides convenience
// functions to construct each status code.
//
// Example:
//
// absl::Status myFunction(absl::string_view fname, ...) {
// ...
// // encounter error
// if (error condition) {
// // Construct an absl::StatusCode::kInvalidArgument error
// return absl::InvalidArgumentError("bad mode");
// }
// // else, return OK
// return absl::OkStatus();
// }
//
// Users handling status error codes should prefer checking for an OK status
// using the `ok()` member function. Handling multiple error codes may justify
// use of switch statement, but only check for error codes you know how to
// handle; do not try to exhaustively match against all canonical error codes.
// Errors that cannot be handled should be logged and/or propagated for higher
// levels to deal with. If you do use a switch statement, make sure that you
// also provide a `default:` switch case, so that code does not break as other
// canonical codes are added to the API.
//
// Example:
//
// absl::Status result = DoSomething();
// if (!result.ok()) {
// LOG(ERROR) << result;
// }
//
// // Provide a default if switching on multiple error codes
// switch (result.code()) {
// // The user hasn't authenticated. Ask them to reauth
// case absl::StatusCode::kUnauthenticated:
// DoReAuth();
// break;
// // The user does not have permission. Log an error.
// case absl::StatusCode::kPermissionDenied:
// LOG(ERROR) << result;
// break;
// // Propagate the error otherwise.
// default:
// return true;
// }
//
// An `absl::Status` can optionally include a payload with more information
// about the error. Typically, this payload serves one of several purposes:
//
// * It may provide more fine-grained semantic information about the error to
// facilitate actionable remedies.
// * It may provide human-readable contextual information that is more
// appropriate to display to an end user.
//
// Example:
//
// absl::Status result = DoSomething();
// // Inform user to retry after 30 seconds
// // See more error details in googleapis/google/rpc/error_details.proto
// if (absl::IsResourceExhausted(result)) {
// google::rpc::RetryInfo info;
// info.retry_delay().seconds() = 30;
// // Payloads require a unique key (a URL to ensure no collisions with
// // other payloads), and an `absl::Cord` to hold the encoded data.
// absl::string_view url = "type.googleapis.com/google.rpc.RetryInfo";
// result.SetPayload(url, info.SerializeAsCord());
// return result;
// }
//
//
// Returned Status objects may not be ignored. status_internal.h has a forward
// declaration of the form
// class ABSL_MUST_USE_RESULT Status;
class Status final {
public:
// Constructors
// This default constructor creates an OK status with no message or payload.
// Avoid this constructor and prefer explicit construction of an OK status
// with `absl::OkStatus()`.
Status();
// Creates a status in the canonical error space with the specified
// `absl::StatusCode` and error message. If `code == absl::StatusCode::kOk`, // NOLINT
// `msg` is ignored and an object identical to an OK status is constructed.
//
// The `msg` string must be in UTF-8. The implementation may complain (e.g., // NOLINT
// by printing a warning) if it is not.
Status(absl::StatusCode code, absl::string_view msg);
Status(const Status&);
Status& operator=(const Status& x);
// Move operators
// The moved-from state is valid but unspecified.
Status(Status&&) noexcept;
Status& operator=(Status&&);
~Status();
// Status::Update()
//
// Updates the existing status with `new_status` provided that `this->ok()`.
// If the existing status already contains a non-OK error, this update has no
// effect and preserves the current data. Note that this behavior may change
// in the future to augment a current non-ok status with additional
// information about `new_status`.
//
// `Update()` provides a convenient way of keeping track of the first error
// encountered.
//
// Example:
// // Instead of "if (overall_status.ok()) overall_status = new_status"
// overall_status.Update(new_status);
//
void Update(const Status& new_status);
void Update(Status&& new_status);
// Status::ok()
//
// Returns `true` if `this->code()` == `absl::StatusCode::kOk`,
// indicating the absence of an error.
// Prefer checking for an OK status using this member function.
ABSL_MUST_USE_RESULT bool ok() const;
// Status::code()
//
// Returns the canonical error code of type `absl::StatusCode` of this status.
absl::StatusCode code() const;
// Status::raw_code()
//
// Returns a raw (canonical) error code corresponding to the enum value of
// `google.rpc.Code` definitions within
// These values could be out of the range of canonical `absl::StatusCode`
// enum values.
//
// NOTE: This function should only be called when converting to an associated
// wire format. Use `Status::code()` for error handling.
int raw_code() const;
// Status::message()
//
// Returns the error message associated with this error code, if available.
// Note that this message rarely describes the error code. It is not unusual
// for the error message to be the empty string. As a result, prefer
// `operator<<` or `Status::ToString()` for debug logging.
absl::string_view message() const;
friend bool operator==(const Status&, const Status&);
friend bool operator!=(const Status&, const Status&);
// Status::ToString()
//
// Returns a string based on the `mode`. By default, it returns combination of
// the error code name, the message and any associated payload messages. This
// string is designed simply to be human readable and its exact format should
// not be load bearing. Do not depend on the exact format of the result of
// `ToString()` which is subject to change.
//
// The printed code name and the message are generally substrings of the
// result, and the payloads to be printed use the status payload printer
// mechanism (which is internal).
std::string ToString(
StatusToStringMode mode = StatusToStringMode::kDefault) const;
// Support `absl::StrCat`, `absl::StrFormat`, etc.
template <typename Sink>
friend void AbslStringify(Sink& sink, const Status& status) {
sink.Append(status.ToString(StatusToStringMode::kWithEverything));
}
// Status::IgnoreError()
//
// Ignores any errors. This method does nothing except potentially suppress
// complaints from any tools that are checking that errors are not dropped on
// the floor.
void IgnoreError() const;
// swap()
//
// Swap the contents of one status with another.
friend void swap(Status& a, Status& b);
//----------------------------------------------------------------------------
// Payload Management APIs
//----------------------------------------------------------------------------
// A payload may be attached to a status to provide additional context to an
// error that may not be satisfied by an existing `absl::StatusCode`.
// Typically, this payload serves one of several purposes:
//
// * It may provide more fine-grained semantic information about the error
// to facilitate actionable remedies.
// * It may provide human-readable contextual information that is more
// appropriate to display to an end user.
//
// A payload consists of a [key,value] pair, where the key is a string
// referring to a unique "type URL" and the value is an object of type
// `absl::Cord` to hold the contextual data.
//
// The "type URL" should be unique and follow the format of a URL
// documentation or schema on how to interpret its associated data. For
// example, the default type URL for a protobuf message type is
// "type.googleapis.com/packagename.messagename". Other custom wire formats
// should define the format of type URL in a similar practice so as to
// minimize the chance of conflict between type URLs.
// Users should ensure that the type URL can be mapped to a concrete
// C++ type if they want to deserialize the payload and read it effectively.
//
// To attach a payload to a status object, call `Status::SetPayload()`,
// passing it the type URL and an `absl::Cord` of associated data. Similarly,
// to extract the payload from a status, call `Status::GetPayload()`. You
// may attach multiple payloads (with differing type URLs) to any given
// status object, provided that the status is currently exhibiting an error
// code (i.e. is not OK).
// Status::GetPayload()
//
// Gets the payload of a status given its unique `type_url` key, if present.
absl::optional<absl::Cord> GetPayload(absl::string_view type_url) const;
// Status::SetPayload()
//
// Sets the payload for a non-ok status using a `type_url` key, overwriting
// any existing payload for that `type_url`.
//
// NOTE: This function does nothing if the Status is ok.
void SetPayload(absl::string_view type_url, absl::Cord payload);
// Status::ErasePayload()
//
// Erases the payload corresponding to the `type_url` key. Returns `true` if
// the payload was present.
bool ErasePayload(absl::string_view type_url);
// Status::ForEachPayload()
//
// Iterates over the stored payloads and calls the
// `visitor(type_key, payload)` callable for each one.
//
// NOTE: The order of calls to `visitor()` is not specified and may change at
// any time.
//
// NOTE: Any mutation on the same 'absl::Status' object during visitation is
// forbidden and could result in undefined behavior.
void ForEachPayload(
absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
const;
private:
friend Status CancelledError();
// Creates a status in the canonical error space with the specified
// code, and an empty error message.
explicit Status(absl::StatusCode code);
// Underlying constructor for status from a rep_.
explicit Status(uintptr_t rep) : rep_(rep) {}
static void Ref(uintptr_t rep);
static void Unref(uintptr_t rep);
// REQUIRES: !ok()
// Ensures rep is not inlined or shared with any other Status.
static status_internal::StatusRep* PrepareToModify(uintptr_t rep);
// MSVC 14.0 limitation requires the const.
static constexpr const char kMovedFromString[] =
"Status accessed after move.";
static const std::string* EmptyString();
static const std::string* MovedFromString();
// Returns whether rep contains an inlined representation.
// See rep_ for details.
static constexpr bool IsInlined(uintptr_t rep);
// Indicates whether this Status was the rhs of a move operation. See rep_
// for details.
static constexpr bool IsMovedFrom(uintptr_t rep);
static constexpr uintptr_t MovedFromRep();
// Convert between error::Code and the inlined uintptr_t representation used
// by rep_. See rep_ for details.
static constexpr uintptr_t CodeToInlinedRep(absl::StatusCode code);
static constexpr absl::StatusCode InlinedRepToCode(uintptr_t rep);
// Converts between StatusRep* and the external uintptr_t representation used
// by rep_. See rep_ for details.
static uintptr_t PointerToRep(status_internal::StatusRep* r);
static const status_internal::StatusRep* RepToPointer(uintptr_t r);
static std::string ToStringSlow(uintptr_t rep, StatusToStringMode mode);
// Status supports two different representations.
// - When the low bit is set it is an inlined representation.
// It uses the canonical error space, no message or payload.
// The error code is (rep_ >> 2).
// The (rep_ & 2) bit is the "moved from" indicator, used in IsMovedFrom().
// - When the low bit is off it is an external representation.
// In this case all the data comes from a heap allocated Rep object.
// rep_ is a status_internal::StatusRep* pointer to that structure.
uintptr_t rep_;
friend class status_internal::StatusRep;
};
// OkStatus()
//
// Returns an OK status, equivalent to a default constructed instance. Prefer
// usage of `absl::OkStatus()` when constructing such an OK status.
Status OkStatus();
// operator<<()
//
// Prints a human-readable representation of `x` to `os`.
std::ostream& operator<<(std::ostream& os, const Status& x);
// IsAborted()
// IsAlreadyExists()
// IsCancelled()
// IsDataLoss()
// IsDeadlineExceeded()
// IsFailedPrecondition()
// IsInternal()
// IsInvalidArgument()
// IsNotFound()
// IsOutOfRange()
// IsPermissionDenied()
// IsResourceExhausted()
// IsUnauthenticated()
// IsUnavailable()
// IsUnimplemented()
// IsUnknown()
//
// These convenience functions return `true` if a given status matches the
// `absl::StatusCode` error code of its associated function.
ABSL_MUST_USE_RESULT bool IsAborted(const Status& status);
ABSL_MUST_USE_RESULT bool IsAlreadyExists(const Status& status);
ABSL_MUST_USE_RESULT bool IsCancelled(const Status& status);
ABSL_MUST_USE_RESULT bool IsDataLoss(const Status& status);
ABSL_MUST_USE_RESULT bool IsDeadlineExceeded(const Status& status);
ABSL_MUST_USE_RESULT bool IsFailedPrecondition(const Status& status);
ABSL_MUST_USE_RESULT bool IsInternal(const Status& status);
ABSL_MUST_USE_RESULT bool IsInvalidArgument(const Status& status);
ABSL_MUST_USE_RESULT bool IsNotFound(const Status& status);
ABSL_MUST_USE_RESULT bool IsOutOfRange(const Status& status);
ABSL_MUST_USE_RESULT bool IsPermissionDenied(const Status& status);
ABSL_MUST_USE_RESULT bool IsResourceExhausted(const Status& status);
ABSL_MUST_USE_RESULT bool IsUnauthenticated(const Status& status);
ABSL_MUST_USE_RESULT bool IsUnavailable(const Status& status);
ABSL_MUST_USE_RESULT bool IsUnimplemented(const Status& status);
ABSL_MUST_USE_RESULT bool IsUnknown(const Status& status);
// AbortedError()
// AlreadyExistsError()
// CancelledError()
// DataLossError()
// DeadlineExceededError()
// FailedPreconditionError()
// InternalError()
// InvalidArgumentError()
// NotFoundError()
// OutOfRangeError()
// PermissionDeniedError()
// ResourceExhaustedError()
// UnauthenticatedError()
// UnavailableError()
// UnimplementedError()
// UnknownError()
//
// These convenience functions create an `absl::Status` object with an error
// code as indicated by the associated function name, using the error message
// passed in `message`.
Status AbortedError(absl::string_view message);
Status AlreadyExistsError(absl::string_view message);
Status CancelledError(absl::string_view message);
Status DataLossError(absl::string_view message);
Status DeadlineExceededError(absl::string_view message);
Status FailedPreconditionError(absl::string_view message);
Status InternalError(absl::string_view message);
Status InvalidArgumentError(absl::string_view message);
Status NotFoundError(absl::string_view message);
Status OutOfRangeError(absl::string_view message);
Status PermissionDeniedError(absl::string_view message);
Status ResourceExhaustedError(absl::string_view message);
Status UnauthenticatedError(absl::string_view message);
Status UnavailableError(absl::string_view message);
Status UnimplementedError(absl::string_view message);
Status UnknownError(absl::string_view message);
// ErrnoToStatusCode()
//
// Returns the StatusCode for `error_number`, which should be an `errno` value.
// references.
absl::StatusCode ErrnoToStatusCode(int error_number);
// ErrnoToStatus()
//
// Convenience function that creates a `absl::Status` using an `error_number`,
// which should be an `errno` value.
Status ErrnoToStatus(int error_number, absl::string_view message);
//------------------------------------------------------------------------------
// Implementation details follow
//------------------------------------------------------------------------------
inline Status::Status() : Status(absl::StatusCode::kOk) {}
inline Status::Status(absl::StatusCode code) : Status(CodeToInlinedRep(code)) {}
inline Status::Status(const Status& x) : Status(x.rep_) { Ref(rep_); }
inline Status& Status::operator=(const Status& x) {
uintptr_t old_rep = rep_;
if (x.rep_ != old_rep) {
Ref(x.rep_);
rep_ = x.rep_;
Unref(old_rep);
}
return *this;
}
inline Status::Status(Status&& x) noexcept : Status(x.rep_) {
x.rep_ = MovedFromRep();
}
inline Status& Status::operator=(Status&& x) {
uintptr_t old_rep = rep_;
if (x.rep_ != old_rep) {
rep_ = x.rep_;
x.rep_ = MovedFromRep();
Unref(old_rep);
}
return *this;
}
inline void Status::Update(const Status& new_status) {
if (ok()) {
*this = new_status;
}
}
inline void Status::Update(Status&& new_status) {
if (ok()) {
*this = std::move(new_status);
}
}
inline Status::~Status() { Unref(rep_); }
inline bool Status::ok() const {
return rep_ == CodeToInlinedRep(absl::StatusCode::kOk);
}
inline absl::StatusCode Status::code() const {
return status_internal::MapToLocalCode(raw_code());
}
inline int Status::raw_code() const {
if (IsInlined(rep_)) return static_cast<int>(InlinedRepToCode(rep_));
return static_cast<int>(RepToPointer(rep_)->code());
}
inline absl::string_view Status::message() const {
return !IsInlined(rep_)
? RepToPointer(rep_)->message()
: (IsMovedFrom(rep_) ? absl::string_view(kMovedFromString)
: absl::string_view());
}
inline bool operator==(const Status& lhs, const Status& rhs) {
if (lhs.rep_ == rhs.rep_) return true;
if (Status::IsInlined(lhs.rep_)) return false;
if (Status::IsInlined(rhs.rep_)) return false;
return *Status::RepToPointer(lhs.rep_) == *Status::RepToPointer(rhs.rep_);
}
inline bool operator!=(const Status& lhs, const Status& rhs) {
return !(lhs == rhs);
}
inline std::string Status::ToString(StatusToStringMode mode) const {
return ok() ? "OK" : ToStringSlow(rep_, mode);
}
inline void Status::IgnoreError() const {
// no-op
}
inline void swap(absl::Status& a, absl::Status& b) {
using std::swap;
swap(a.rep_, b.rep_);
}
inline absl::optional<absl::Cord> Status::GetPayload(
absl::string_view type_url) const {
if (IsInlined(rep_)) return absl::nullopt;
return RepToPointer(rep_)->GetPayload(type_url);
}
inline void Status::SetPayload(absl::string_view type_url, absl::Cord payload) {
if (ok()) return;
status_internal::StatusRep* rep = PrepareToModify(rep_);
rep->SetPayload(type_url, std::move(payload));
rep_ = PointerToRep(rep);
}
inline bool Status::ErasePayload(absl::string_view type_url) {
if (IsInlined(rep_)) return false;
status_internal::StatusRep* rep = PrepareToModify(rep_);
auto res = rep->ErasePayload(type_url);
rep_ = res.new_rep;
return res.erased;
}
inline void Status::ForEachPayload(
absl::FunctionRef<void(absl::string_view, const absl::Cord&)> visitor)
const {
if (IsInlined(rep_)) return;
RepToPointer(rep_)->ForEachPayload(visitor);
}
constexpr bool Status::IsInlined(uintptr_t rep) { return (rep & 1) != 0; }
constexpr bool Status::IsMovedFrom(uintptr_t rep) { return (rep & 2) != 0; }
constexpr uintptr_t Status::CodeToInlinedRep(absl::StatusCode code) {
return (static_cast<uintptr_t>(code) << 2) + 1;
}
constexpr absl::StatusCode Status::InlinedRepToCode(uintptr_t rep) {
ABSL_ASSERT(IsInlined(rep));
return static_cast<absl::StatusCode>(rep >> 2);
}
constexpr uintptr_t Status::MovedFromRep() {
return CodeToInlinedRep(absl::StatusCode::kInternal) | 2;
}
inline const status_internal::StatusRep* Status::RepToPointer(uintptr_t rep) {
assert(!IsInlined(rep));
return reinterpret_cast<const status_internal::StatusRep*>(rep);
}
inline uintptr_t Status::PointerToRep(status_internal::StatusRep* rep) {
return reinterpret_cast<uintptr_t>(rep);
}
inline void Status::Ref(uintptr_t rep) {
if (!IsInlined(rep)) RepToPointer(rep)->Ref();
}
inline void Status::Unref(uintptr_t rep) {
if (!IsInlined(rep)) RepToPointer(rep)->Unref();
}
inline Status OkStatus() { return Status(); }
// Creates a `Status` object with the `absl::StatusCode::kCancelled` error code
// and an empty message. It is provided only for efficiency, given that
// message-less kCancelled errors are common in the infrastructure.
inline Status CancelledError() { return Status(absl::StatusCode::kCancelled); }
// Retrieves a message's status as a null terminated C string. The lifetime of
// this string is tied to the lifetime of the status object itself.
//
// If the status's message is empty, the empty string is returned.
//
// StatusMessageAsCStr exists for C support. Use `status.message()` in C++.
const char* StatusMessageAsCStr(
const Status& status ABSL_ATTRIBUTE_LIFETIME_BOUND);
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_STATUS_STATUS_H_