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diff --git a/third_party/abseil_cpp/absl/status/status.h b/third_party/abseil_cpp/absl/status/status.h new file mode 100644 index 000000000000..c4d6fce09050 --- /dev/null +++ b/third_party/abseil_cpp/absl/status/status.h @@ -0,0 +1,817 @@ +// 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. +// +// ----------------------------------------------------------------------------- +// 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 gracefully +// handling errors across API boundaries (and in particular across RPC +// boundaries). 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 <iostream> +#include <string> + +#include "absl/container/inlined_vector.h" +#include "absl/status/internal/status_internal.h" +#include "absl/strings/cord.h" +#include "absl/types/optional.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 +// RPC error codes indicated in https://cloud.google.com/apis/design/errors. +// +// 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 travel RPC boundaries, these codes are tied to the +// `google.rpc.Code` definitions within +// https://github.com/googleapis/googleapis/blob/master/google/rpc/code.proto +// 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 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 +}; + +// 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::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 constuct 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 contexual 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; +// } +// +class ABSL_MUST_USE_RESULT 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`, + // `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., + // 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->ok()`. 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 + // https://github.com/googleapis/googleapis/blob/master/google/rpc/code.proto. + // 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 + // `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 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() const; + + // 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 satisifed 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 contexual 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 + // (https://en.wikipedia.org/wiki/URL) and, ideally, provide some + // 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( + const std::function<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); + + static void UnrefNonInlined(uintptr_t rep); + static void Ref(uintptr_t rep); + static void Unref(uintptr_t rep); + + // REQUIRES: !ok() + // Ensures rep_ is not shared with any other Status. + void PrepareToModify(); + + const status_internal::Payloads* GetPayloads() const; + status_internal::Payloads* GetPayloads(); + + // Takes ownership of payload. + static uintptr_t NewRep(absl::StatusCode code, absl::string_view msg, + std::unique_ptr<status_internal::Payloads> payload); + static bool EqualsSlow(const absl::Status& a, const absl::Status& b); + + // 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 bool IsInlined(uintptr_t rep); + + // Indicates whether this Status was the rhs of a move operation. See rep_ + // for details. + static bool IsMovedFrom(uintptr_t rep); + static uintptr_t MovedFromRep(); + + // Convert between error::Code and the inlined uintptr_t representation used + // by rep_. See rep_ for details. + static uintptr_t CodeToInlinedRep(absl::StatusCode code); + static 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 status_internal::StatusRep* RepToPointer(uintptr_t r); + + // Returns string for non-ok Status. + std::string ToStringSlow() const; + + // Status supports two different representations. + // - When the low bit is off 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 on it is an external representation. + // In this case all the data comes from a heap allocated Rep object. + // (rep_ - 1) is a status_internal::StatusRep* pointer to that structure. + uintptr_t rep_; +}; + +// 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); + +//------------------------------------------------------------------------------ +// Implementation details follow +//------------------------------------------------------------------------------ + +inline Status::Status() : rep_(CodeToInlinedRep(absl::StatusCode::kOk)) {} + +inline Status::Status(absl::StatusCode code) : rep_(CodeToInlinedRep(code)) {} + +inline Status::Status(const Status& x) : rep_(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 : rep_(x.rep_) { + x.rep_ = MovedFromRep(); +} + +inline Status& Status::operator=(Status&& x) { + uintptr_t old_rep = 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::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) { + return lhs.rep_ == rhs.rep_ || Status::EqualsSlow(lhs, rhs); +} + +inline bool operator!=(const Status& lhs, const Status& rhs) { + return !(lhs == rhs); +} + +inline std::string Status::ToString() const { + return ok() ? "OK" : ToStringSlow(); +} + +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 const status_internal::Payloads* Status::GetPayloads() const { + return IsInlined(rep_) ? nullptr : RepToPointer(rep_)->payloads.get(); +} + +inline status_internal::Payloads* Status::GetPayloads() { + return IsInlined(rep_) ? nullptr : RepToPointer(rep_)->payloads.get(); +} + +inline bool Status::IsInlined(uintptr_t rep) { return (rep & 1) == 0; } + +inline bool Status::IsMovedFrom(uintptr_t rep) { + return IsInlined(rep) && (rep & 2) != 0; +} + +inline uintptr_t Status::MovedFromRep() { + return CodeToInlinedRep(absl::StatusCode::kInternal) | 2; +} + +inline uintptr_t Status::CodeToInlinedRep(absl::StatusCode code) { + return static_cast<uintptr_t>(code) << 2; +} + +inline absl::StatusCode Status::InlinedRepToCode(uintptr_t rep) { + assert(IsInlined(rep)); + return static_cast<absl::StatusCode>(rep >> 2); +} + +inline status_internal::StatusRep* Status::RepToPointer(uintptr_t rep) { + assert(!IsInlined(rep)); + return reinterpret_cast<status_internal::StatusRep*>(rep - 1); +} + +inline uintptr_t Status::PointerToRep(status_internal::StatusRep* rep) { + return reinterpret_cast<uintptr_t>(rep) + 1; +} + +inline void Status::Ref(uintptr_t rep) { + if (!IsInlined(rep)) { + RepToPointer(rep)->ref.fetch_add(1, std::memory_order_relaxed); + } +} + +inline void Status::Unref(uintptr_t rep) { + if (!IsInlined(rep)) { + UnrefNonInlined(rep); + } +} + +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); } + +ABSL_NAMESPACE_END +} // namespace absl + +#endif // ABSL_STATUS_STATUS_H_ |