Error Class Reference

Lightweight error code wrapper for the promeki library. More...

#include <error.h>

Public Types
enum	Code {   Ok = 0 , UnsupportedSystemError , LibraryFailure , SingularMatrix ,   NotImplemented , PixelFormatNotSupported , OutOfRange , PermissionDenied ,   TryAgain , BadFileDesc , Busy , Exists ,   BadAddress , TooLarge , Interrupt , Invalid ,   IOError , IsDir , TooManyOpenFiles , TooManyOpenSysFiles ,   NotExist , NoMem , NoSpace , NotDir ,   NoPermission , ReadOnly , IllegalSeek , Timeout ,   CrossDeviceLink , NoFrameRate , AlreadyOpen , NotSupported ,   OpenFailed , NotOpen , EndOfFile , InvalidArgument ,   InvalidDimension , NotHostAccessible , BufferTooSmall }
	Error codes for the promeki library. More...

Public Member Functions
	Error (Code code=Ok)
	Constructs an Error with the given code.
	~Error ()
	Destructor.
bool	operator== (const Error &other) const
	Returns true if both errors have the same code.
bool	operator!= (const Error &other) const
	Returns true if the errors have different codes.
bool	operator< (const Error &other) const
	Less-than comparison by error code.
bool	operator<= (const Error &other) const
	Less-than-or-equal comparison by error code.
bool	operator> (const Error &other) const
	Greater-than comparison by error code.
bool	operator>= (const Error &other) const
	Greater-than-or-equal comparison by error code.
Code	code () const
	Returns the error code.
bool	isOk () const
	Returns true if the error code is Ok (no error).
bool	isError () const
	Returns true if the error code indicates an error.
const String &	name () const
	Returns the human-readable name of the error code.
const String &	desc () const
	Returns a human-readable description of the error.
const String &	systemErrorName () const
	Returns the name of the corresponding POSIX errno symbol.
int	systemError () const
	Returns the POSIX errno value that maps to this error code.

Static Public Member Functions
static Error	syserr ()
	Creates an Error from the last system error.
static Error	syserr (int errnum)
	Creates an Error from an explicit POSIX errno value.
static Error	syserr (const std::error_code &ec)
	Creates an Error from a std::error_code.

Detailed Description

Lightweight error code wrapper for the promeki library.

Encapsulates an error code from the Code enumeration and provides comparison operators, human-readable names, descriptions, and

Example

Error err;
// Functions use Error* for fallible results:
auto val = someFunction(&err);
if(err.isError()) {
    String msg = err.description();
}
 
// Direct comparison
if(err == Error::NotExist) { ... }

a mapping to the corresponding POSIX errno value when applicable.

Member Enumeration Documentation

Code

enum Error::Code

Error codes for the promeki library.

New codes should be added here whenever an existing code would be an imprecise fit. Prefer specific, descriptive codes over reusing generic ones. Codes that map to POSIX errno values are noted in error.cpp; domain-specific codes have no errno mapping.

Enumerator
Ok	No error.
UnsupportedSystemError	Unmapped system error.
LibraryFailure	An external library call failed.
SingularMatrix	Matrix is singular and cannot be inverted.
NotImplemented	Feature is not implemented.
PixelFormatNotSupported	Pixel format is not supported.
OutOfRange	Value is out of range.
PermissionDenied	Permission denied (EACCES).
TryAgain	Resource temporarily unavailable (EAGAIN).
BadFileDesc	Bad file descriptor (EBADF).
Busy	Resource is busy (EBUSY).
Exists	File or resource already exists (EEXIST).
BadAddress	Bad memory address (EFAULT).
TooLarge	File too large (EFBIG).
Interrupt	Interrupted system call (EINTR).
Invalid	Invalid value or argument (EINVAL).
IOError	Input/output error (EIO).
IsDir	Is a directory (EISDIR).
TooManyOpenFiles	Too many open files in process (EMFILE).
TooManyOpenSysFiles	Too many open files system-wide (ENFILE).
NotExist	File or resource does not exist (ENOENT).
NoMem	Out of memory (ENOMEM).
NoSpace	No space left on device (ENOSPC).
NotDir	Not a directory (ENOTDIR).
NoPermission	Operation not permitted (EPERM).
ReadOnly	Read-only file system (EROFS).
IllegalSeek	Illegal seek (ESPIPE).
Timeout	Operation timed out.
CrossDeviceLink	Cross-device link (EXDEV).
NoFrameRate	No frame rate has been set.
AlreadyOpen	Resource is already open.
NotSupported	Operation is not supported.
OpenFailed	Failed to open a resource.
NotOpen	Resource is not open.
EndOfFile	End of file reached.
InvalidArgument	Invalid argument supplied.
InvalidDimension	Invalid dimension value.
NotHostAccessible	Memory is not host-accessible.
BufferTooSmall	Buffer is too small for the operation.

Constructor & Destructor Documentation

Error()

Error::Error ( Code  code = Ok )

inline

Constructs an Error with the given code.

Parameters

code	The error code (default: Ok).

Member Function Documentation

code()

Code Error::code ( ) const

inline

Returns the error code.

Returns

The Code enumeration value.

desc()

const String & Error::desc

(

)

const

Returns a human-readable description of the error.

Returns

A descriptive String for the error code.

isError()

bool Error::isError ( ) const

inline

Returns true if the error code indicates an error.

Returns

True when the code is non-zero.

isOk()

bool Error::isOk ( ) const

inline

Returns true if the error code is Ok (no error).

Returns

True when the code is zero.

name()

const String & Error::name

(

)

const

Returns the human-readable name of the error code.

Returns

A String such as "Ok", "Invalid", "IOError", etc.

syserr() [1/3]

static Error Error::syserr ( )

static

Creates an Error from the last system error.

On POSIX, reads errno. On Windows, reads GetLastError().

Returns

An Error whose code maps to the system error.

syserr() [2/3]

static Error Error::syserr ( const std::error_code &  ec )

static

Creates an Error from a std::error_code.

Handles both POSIX (generic_category / system_category on POSIX) and Windows (system_category on Windows) error codes correctly. Returns Ok when the error_code has no error.

Parameters

ec	The std::error_code to translate.

Returns

An Error whose code maps to the given error_code.

syserr() [3/3]

static Error Error::syserr ( int  errnum )

static

Creates an Error from an explicit POSIX errno value.

Parameters

errnum

The errno value to translate.

Returns

An Error whose code maps to the given errno.

systemError()

int Error::systemError

(

)

const

Returns the POSIX errno value that maps to this error code.

Returns

The errno value, or 0 if there is no mapping.

systemErrorName()

const String & Error::systemErrorName

(

)

const

Returns the name of the corresponding POSIX errno symbol.

Returns

A String such as "EINVAL", or an empty string if unmapped.

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The documentation for this class was generated from the following file:

• include/promeki/core/error.h