Tizen Native API  5.5

This group discusses the functions that provide error management for projects.

The Eina error module provides a way to manage errors in a simple but powerful way in libraries and modules. It is also used in Eina itself. An extension to libC's errno and strerror() facilities, this is extensible and recommended for other libraries and applications as well.

While libC's errno is fixed, Eina_Error can be extended by libraries and applications with domain-specific codes and associated error messages. All errno.h codes are usable seamlessly with Eina_Error. The constants defined in errno.h will have messages as reported by strerror() in eina_error_msg_get()

Success (no-error) condition is reported with Eina_Error 0 (EINA_ERROR_NO_ERROR).

A simple example of how to use this can be seen here.

Functions

Eina_Error eina_error_msg_register (const char *msg)
 Registers a new error type.
Eina_Error eina_error_msg_static_register (const char *msg)
 Registers a new error type, statically allocated message.
Eina_Bool eina_error_msg_modify (Eina_Error error, const char *msg)
 Changes the message of an already registered message.
Eina_Error eina_error_get (void)
 Returns the last set error.
void eina_error_set (Eina_Error err)
 Sets the last error.
const char * eina_error_msg_get (Eina_Error error)
 Returns the description of the given error number.
Eina_Error eina_error_find (const char *msg)
 Finds the Eina_Error corresponding to a message string.

Typedefs

typedef int Eina_Error
 The integer type containing the error type.
typedef Eina_Bool Eina_Success_Flag
 A flag indicating a function completed succesfully.

Defines

#define EINA_ERROR_NO_ERROR   ((Eina_Error)0)
 No error reported.

Define Documentation

#define EINA_ERROR_NO_ERROR   ((Eina_Error)0)

No error reported.

This is a convenience macro for people that are extra verbose, same as "0".


Typedef Documentation

The integer type containing the error type.

Errors are registered with eina_error_msg_register(), eina_error_msg_static_register() or those inherited from the system's errno.h such as ENOMEM.

A flag indicating a function completed succesfully.

Errors are reported with a EINA_FALSE value for Eina_Success_Flag return and success with a EINA_TRUE.


Function Documentation

Eina_Error eina_error_find ( const char *  msg)

Finds the Eina_Error corresponding to a message string.

This function attempts to match msg with its corresponding Eina_Error value. If no such value is found, 0 is returned.

Parameters:
[in]msgThe error message string to match (NOT NULL)
Returns:
The Eina_Error matching msg, otherwise 0 on failure
Note:
this function only works for explicitly registered errors such as the messages given to eina_error_msg_register(), eina_error_msg_static_register() or modified with eina_error_msg_modify().
Since :
3.0

Returns the last set error.

This function returns the last error set by eina_error_set(). The description of the message is returned by eina_error_msg_get().

Returns:
The last error or 0 (EINA_ERROR_NO_ERROR).
Note:
This function is thread safe
Since (EFL) :
1.10, but slower to use.
Since :
3.0f(2.3.1)
Examples:
eina_error_01.c.
const char* eina_error_msg_get ( Eina_Error  error)

Returns the description of the given error number.

This function returns the description of an error that has been registered by eina_error_msg_register(). If an incorrect error is given, then NULL is returned.

Parameters:
[in]errorThe error number
Returns:
The description of the error
Since :
3.0f(2.3.1)
Examples:
eina_error_01.c.
Eina_Bool eina_error_msg_modify ( Eina_Error  error,
const char *  msg 
)

Changes the message of an already registered message.

This function modifies the message associated with error and changes it to msg. If the error is previously registered by eina_error_msg_static_register then the string is not duplicated, otherwise the previous message is unref'ed and msg is copied.

Parameters:
[in]errorThe Eina_Error to change the message of
[in]msgThe description of the error
This string is duplicated only if the error is registered with eina_error_msg_register, otherwise it must remain intact for the duration.
Returns:
EINA_TRUE if successful, otherwise EINA_FALSE on error
Note:
It is not possible to modify messages that exist in libC's errno.h, such as ENOMEM or EBADF.
See also:
eina_error_msg_register()
Since :
3.0f(2.3.1)
Eina_Error eina_error_msg_register ( const char *  msg)

Registers a new error type.

This function stores the error message described by msg in a list. The returned value is a unique identifier greater than or equal to 1. The description can be retrieved later by passing the returned value to eina_error_msg_get().

Parameters:
[in]msgThe description of the error
It is duplicated using eina_stringshare_add().
Returns:
The unique number identifier for this error
Note:
There is no need to register messages that exist in libC's errno.h, such as ENOMEM or EBADF.
See also:
eina_error_msg_static_register()
Since :
3.0f(2.3.1)

Registers a new error type, statically allocated message.

This function stores the error message described by msg in a list. The returned value is a unique identifier greater than or equal to 1. The description can be retrieved later by passing the returned value to eina_error_msg_get().

Parameters:
[in]msgThe description of the error
This string is not duplicated and thus the given pointer should live during the usage of eina_error.
Returns:
The unique number identifier for this error
Note:
There is no need to register messages that exist in libC's errno.h, such as ENOMEM or EBADF.
See also:
eina_error_msg_register()
Since :
3.0f(2.3.1)
Examples:
eina_error_01.c.
void eina_error_set ( Eina_Error  err)

Sets the last error.

This function sets the last error identifier. The last error can be retrieved by eina_error_get().

Parameters:
[in]errThe error identifier
Note:
This is also used to clear previous errors, in which case err should be 0 (EINA_ERROR_NO_ERROR).
This function is thread safe
Since (EFL) :
1.10, but slower to use.
Since :
3.0f(2.3.1)
Examples:
eina_error_01.c.

Variable Documentation

The error identifier corresponding to lack of memory.

Since :
3.0f(2.3.1)
Deprecated:
since 1.19, same as ENOMEM from errno.h