RMessagePtr2 Class Reference

#include <e32cmn.h>

class RMessagePtr2

Protected Attributes
TInt	iHandle

Public Member Functions
	RMessagePtr2()
IMPORT_C TInt	Client(RThread &, TOwnerType)
IMPORT_C TBool	ClientIsRealtime()
void	ClientL(RThread &, TOwnerType)
IMPORT_C TUint	ClientProcessFlags()
IMPORT_C const TRequestStatus *	ClientStatus()
IMPORT_C void	Complete(TInt)
IMPORT_C void	Complete(RHandleBase)
IMPORT_C TInt	GetDesLength(TInt)
IMPORT_C TInt	GetDesLengthL(TInt)
IMPORT_C TInt	GetDesMaxLength(TInt)
IMPORT_C TInt	GetDesMaxLengthL(TInt)
TInt	Handle()
TBool	HasCapability(TCapability, const char *)
TBool	HasCapability(TCapability, TCapability, const char *)
void	HasCapabilityL(TCapability, const char *)
void	HasCapabilityL(TCapability, TCapability, const char *)
TUid	Identity()
TBool	IsNull()
IMPORT_C void	Kill(TInt)
IMPORT_C void	Panic(const TDesC &, TInt)
IMPORT_C TInt	Read(TInt, TDes8 &, TInt)
IMPORT_C TInt	Read(TInt, TDes16 &, TInt)
IMPORT_C void	ReadL(TInt, TDes8 &, TInt)
IMPORT_C void	ReadL(TInt, TDes16 &, TInt)
IMPORT_C TSecureId	SecureId()
IMPORT_C TInt	SetProcessPriority(TProcessPriority)
void	SetProcessPriorityL(TProcessPriority)
IMPORT_C void	Terminate(TInt)
IMPORT_C TVendorId	VendorId()
IMPORT_C TInt	Write(TInt, const TDesC8 &, TInt)
IMPORT_C TInt	Write(TInt, const TDesC16 &, TInt)
IMPORT_C void	WriteL(TInt, const TDesC8 &, TInt)
IMPORT_C void	WriteL(TInt, const TDesC16 &, TInt)

Detailed Description

A handle to a message sent by the client to the server.

A server's interaction with its clients is channelled through an RMessagePtr2 object, which acts as a handle to a message sent by the client. The details of the original message are kept by the kernel allowing it enforce correct usage of the member functions of this class.

Member Attribute Documentation

iHandle

TInt

iHandle

[protected]

Constructor & Destructor Documentation

RMessagePtr2 ( )

RMessagePtr2

(

)

[inline]

Default constructor

Member Function Documentation

Client ( RThread &, TOwnerType )

IMPORT_C TInt	Client	(	RThread &	aClient,
			TOwnerType	aOwnerType = EOwnerProcess
		)	const

Opens a handle on the client thread.

Parameters
aClient	On successful return, the handle to the client thread.
aOwnerType	An enumeration whose enumerators define the ownership of the handle. If not explicitly specified, EOwnerProcess is taken as default.

Return Value: KErrNone.

ClientIsRealtime ( )

IMPORT_C TBool

ClientIsRealtime

(

)

const

ClientL ( RThread &, TOwnerType )

void	ClientL	(	RThread &	aClient,
			TOwnerType	aOwnerType = EOwnerProcess
		)	const [inline]

Opens a handle on the client thread.

Parameters
aClient	On successful return, the handle to the client thread.
aOwnerType	An enumeration whose enumerators define the ownership of the handle. If not explicitly specified, EOwnerProcess is taken as default.

ClientProcessFlags ( )

IMPORT_C TUint

ClientProcessFlags

(

)

const

ClientStatus ( )

IMPORT_C const TRequestStatus *

ClientStatus

(

)

const

Returns the pointer to the clients TRequestStatus associated with the message.

The return value is intended to be used as a unique identifier (for example, to uniquely identify an asynchronous message when cancelling the request). The memory must never be accessed directly or completed.

Return Value: The clients TRequestStatus (returns NULL if the request is not asynchronous)

Complete ( TInt )

IMPORT_C void

Complete

(

TInt

aReason

)

const

Frees this message.

Parameters
aReason	The completion code.

Complete ( RHandleBase )

IMPORT_C void

Complete

(

RHandleBase

aHandle

)

const

Duplicates the specified handle in the client thread, and returns this handle as a message completion code

Parameters
aHandle	The handle to be duplicated.

GetDesLength ( TInt )

IMPORT_C TInt

GetDesLength

(

TInt

aParam

)

const

Gets the length of a descriptor argument in the client's process.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.

Return Value: The length of the descriptor, if successful. KErrArgument, if aParam has a value outside the valid range. KErrBadDescriptor, if the message argument is not a descriptor type.

GetDesLengthL ( TInt )

IMPORT_C TInt

GetDesLengthL

(

TInt

aParam

)

const

Gets the length of a descriptor argument in the client's process, leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.

Return Value: The length of the descriptor.

Leave Codes
KErrArgument	if aParam has a value outside the valid range.
KErrBadDescriptor,	if the message argument is not a descriptor type.

GetDesMaxLength ( TInt )

IMPORT_C TInt

GetDesMaxLength

(

TInt

aParam

)

const

Gets the maximum length of a descriptor argument in the client's process.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.

Return Value: The maximum length of the descriptor, if successful. KErrArgument, if aParam has a value outside the valid range. KErrBadDescriptor, if the message argument is not a descriptor type.

GetDesMaxLengthL ( TInt )

IMPORT_C TInt

GetDesMaxLengthL

(

TInt

aParam

)

const

Gets the maximum length of a descriptor argument in the client's process, leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.

Return Value: The length of the descriptor.

Leave Codes
KErrArgument	if aParam has a value outside the valid range.
KErrBadDescriptor,	if the message argument is not a descriptor type.

Handle ( )

TInt

Handle

(

)

const [inline]

Gets the message handle value.

Return Value: The message handle value.

HasCapability ( TCapability, const char * )

TBool	HasCapability	(	TCapability	aCapability,
			const char *	aDiagnostic = 0
		)	const [inline]

Check if the process which sent this message has a given capability.

When a check fails the action taken is determined by the system wide Platform Security configuration. If PlatSecDiagnostics is ON, then a diagnostic message is emitted. If PlatSecEnforcement is OFF, then this function will return ETrue even though the check failed.

Parameters
aCapability	The capability to test.
aDiagnostic	A string that will be emitted along with any diagnostic message that may be issued if the test finds the capability is not present. This string must be enclosed in the __PLATSEC_DIAGNOSTIC_STRING macro which enables it to be easily removed from the system.

Return Value: ETrue if process which sent this message has the capability, EFalse otherwise.

HasCapability ( TCapability, TCapability, const char * )

TBool	HasCapability	(	TCapability	aCapability1,
			TCapability	aCapability2,
			const char *	aDiagnostic = 0
		)	const [inline]

Check if the process which sent this message has both of the given capabilities.

Parameters
aCapability1	The first capability to test.
aCapability2	The second capability to test.
aDiagnostic	A string that will be emitted along with any diagnostic message that may be issued if the test finds a capability is not present. This string should be enclosed in the __PLATSEC_DIAGNOSTIC_STRING macro which enables it to be easily removed from the system.

Return Value: ETrue if the process which sent this message has both the capabilities, EFalse otherwise.

HasCapabilityL ( TCapability, const char * )

void	HasCapabilityL	(	TCapability	aCapability,
			const char *	aDiagnosticMessage = 0
		)	const [inline]

Check if the process which sent this message has a given capability.

Parameters
aCapability	The capability to test.
aDiagnosticMessage	A string that will be emitted along with any diagnostic message that may be issued if the test finds the capability is not present. This string must be enclosed in the __PLATSEC_DIAGNOSTIC_STRING macro which enables it to be easily removed from the system.

Leave Codes
KErrPermissionDenied,	if the process does not have the capability.

HasCapabilityL ( TCapability, TCapability, const char * )

void	HasCapabilityL	(	TCapability	aCapability1,
			TCapability	aCapability2,
			const char *	aDiagnosticMessage = 0
		)	const [inline]

Check if the process which sent this message has both of the given capabilities.

Parameters
aCapability1	The first capability to test.
aCapability2	The second capability to test.
aDiagnosticMessage	A string that will be emitted along with any diagnostic message that may be issued if the test finds a capability is not present. This string should be enclosed in the __PLATSEC_DIAGNOSTIC_STRING macro which enables it to be easily removed from the system.

Leave Codes
KErrPermissionDenied,	if the process does not have the capabilities.

Identity ( )

TUid

Identity

(

)

const [inline]

DeprecatedUse SecureId()

IsNull ( )

TBool

IsNull

(

)

const [inline]

Tests whether this message handle is empty.

Return Value: True, if this message handle is empty, false, otherwise.

Kill ( TInt )

IMPORT_C void

Kill

(

TInt

aReason

)

const

Kills the client.

Note that this method also completes the message. A subsequent call to Complete(TInt aReason) would cause a server panic.

Parameters
aReason	The reason code associated with killing the client.

Panic ( const TDesC &, TInt )

IMPORT_C void	Panic	(	const TDesC &	aCategory,
			TInt	aReason
		)	const

Panics the client.

The length of the category name should be no greater than 16; any name with a length greater than 16 is truncated to 16.

Note that this method also completes the message. A subsequent call to Complete(TInt aReason) would cause a server panic.

Parameters
aCategory	The panic category.
aReason	The panic code.

Read ( TInt, TDes8 &, TInt )

IMPORT_C TInt	Read	(	TInt	aParam,
			TDes8 &	aDes,
			TInt	aOffset = 0
		)	const

Reads data from the specified offset within the 8-bit descriptor argument, into the specified target descriptor.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The target descriptor into which the client data is to be written.
aOffset	The offset from the start of the client's descriptor data. If not explicitly specified, the offset defaults to zero.

Return Value: KErrNone, if successful; KErrArgument if aParam has a value outside the valid range, or if aOffset is negative. KErrBadDescriptor, if the message argument is not an 8-bit descriptor.

Read ( TInt, TDes16 &, TInt )

IMPORT_C TInt	Read	(	TInt	aParam,
			TDes16 &	aDes,
			TInt	aOffset = 0
		)	const

Reads data from the specified offset within the 16-bit descriptor argument, into the specified target descriptor.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The target descriptor into which the client data is to be written.
aOffset	The offset from the start of the client's descriptor data. If not explicitly specified, the offset defaults to zero.

Return Value: KErrNone, if successful; KErrArgument if aParam has a value outside the valid range, or if aOffset is negative. KErrBadDescriptor, if the message argument is not a 16-bit descriptor.

ReadL ( TInt, TDes8 &, TInt )

IMPORT_C void	ReadL	(	TInt	aParam,
			TDes8 &	aDes,
			TInt	aOffset = 0
		)	const

Reads data from the specified offset within the 8-bit descriptor argument, into the specified target descriptor, and leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The target descriptor into which the client data is to be written.
aOffset	The offset from the start of the client's descriptor data. If not explicitly specified, the offset defaults to zero.

Leave Codes
KErrArgument	if aParam has a value outside the valid range, or if aOffset is negative.
KErrBadDescriptor,	if the message argument is not an 8-bit descriptor.

ReadL ( TInt, TDes16 &, TInt )

IMPORT_C void	ReadL	(	TInt	aParam,
			TDes16 &	aDes,
			TInt	aOffset = 0
		)	const

Reads data from the specified offset within the 16-bit descriptor argument, into the specified target descriptor, and leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The target descriptor into which the client data is to be written.
aOffset	The offset from the start of the client's descriptor data. If not explicitly specified, the offset defaults to zero.

Leave Codes
KErrArgument	if aParam has a value outside the valid range, or if aOffset is negative.
KErrBadDescriptor,	if the message argument is not a 16-bit descriptor.

SecureId ( )

IMPORT_C TSecureId

SecureId

(

)

const

Return the Secure ID of the process which sent this message.

If an intended use of this method is to check that the Secure ID is a given value, then the use of a TSecurityPolicy object should be considered. E.g. Instead of something like:

		RMessagePtr2& message;
		TInt error = message.SecureId()==KRequiredSecureId ? KErrNone : KErrPermissionDenied;

this could be used;

		RMessagePtr2& message;
		static _LIT_SECURITY_POLICY_S0(mySidPolicy, KRequiredSecureId);
		TBool pass = mySidPolicy().CheckPolicy(message);

This has the benefit that the TSecurityPolicy::CheckPolicy methods are configured by the system wide Platform Security configuration. I.e. are capable of emitting diagnostic messages when a check fails and/or the check can be forced to always pass.

Return Value: The Secure ID.

SetProcessPriority ( TProcessPriority )

IMPORT_C TInt

SetProcessPriority

(

TProcessPriority

aPriority

)

const

Sets the priority of the client's process.

Parameters
aPriority	The priority value.

Return Value: KErrNone, if successful, otherwise one of the other system-wide error codes.

SetProcessPriorityL ( TProcessPriority )

void

SetProcessPriorityL

(

TProcessPriority

aPriority

)

const [inline]

Sets the priority of the client's process.

Parameters
aPriority	The priority value.

Terminate ( TInt )

IMPORT_C void

Terminate

(

TInt

aReason

)

const

Terminates the client.

Note that this method also completes the message. A subsequent call to Complete(TInt aReason) would cause a server panic.

Parameters
aReason	The reason code associated with terminating the client.

VendorId ( )

IMPORT_C TVendorId

VendorId

(

)

const

Return the Vendor ID of the process which sent this message.

If an intended use of this method is to check that the Vendor ID is a given value, then the use of a TSecurityPolicy object should be considered. E.g. Instead of something like:

		RMessagePtr2& message;
		TInt error = message.VendorId()==KRequiredVendorId ? KErrNone : KErrPermissionDenied;

this could be used;

		RMessagePtr2& message;
		static _LIT_SECURITY_POLICY_V0(myVidPolicy, KRequiredVendorId);
		TBool pass = myVidPolicy().CheckPolicy(message);

Return Value: The Vendor ID.

Write ( TInt, const TDesC8 &, TInt )

IMPORT_C TInt	Write	(	TInt	aParam,
			const TDesC8 &	aDes,
			TInt	aOffset = 0
		)	const

Writes data from the specified source descriptor to the specified offset within the 8-bit descriptor argument.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The source descriptor containing the data to be written.
aOffset	The offset from the start of the client's descriptor. If not explicitly specified, the offset defaults to zero.

Return Value: KErrNone, if successful; KErrArgument if aParam has a value outside the valid range, or if aOffset is negative. KErrBadDescriptor, if the message argument is not an 8-bit descriptor; KErrOverflow, if the target descriptor is too small to containt the data.

Write ( TInt, const TDesC16 &, TInt )

IMPORT_C TInt	Write	(	TInt	aParam,
			const TDesC16 &	aDes,
			TInt	aOffset = 0
		)	const

Writes data from the specified source descriptor to the specified offset within the 16-bit descriptor argument.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The source descriptor containing the data to be written.
aOffset	The offset from the start of the client's descriptor. If not explicitly specified, the offset defaults to zero.

Return Value: KErrNone, if successful; KErrArgument if aParam has a value outside the valid range, or if aOffset is negative. KErrBadDescriptor, if the message argument is not an 16-bit descriptor; KErrOverflow, if the target descriptor is too small to containt the data.

WriteL ( TInt, const TDesC8 &, TInt )

IMPORT_C void	WriteL	(	TInt	aParam,
			const TDesC8 &	aDes,
			TInt	aOffset = 0
		)	const

Writes data from the specified source descriptor to the specified offset within the 8-bit descriptor argument, and leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The source descriptor containing the data to be written.
aOffset	The offset from the start of the client's descriptor. If not explicitly specified, the offset defaults to zero.

Leave Codes
KErrArgument	if aParam has a value outside the valid range, or if aOffset is negative.
KErrBadDescriptor,	if the message argument is not an 8-bit descriptor.

WriteL ( TInt, const TDesC16 &, TInt )

IMPORT_C void	WriteL	(	TInt	aParam,
			const TDesC16 &	aDes,
			TInt	aOffset = 0
		)	const

Writes data from the specified source descriptor to the specified offset within the 16-bit descriptor argument, and leaving on failure.

Parameters
aParam	The index value identifying the argument. This is a value in the range 0 to (KMaxMessageArguments-1) inclusive.
aDes	The source descriptor containing the data to be written.
aOffset	The offset from the start of the client's descriptor. If not explicitly specified, the offset defaults to zero.

Leave Codes
KErrArgument	if aParam has a value outside the valid range, or if aOffset is negative.
KErrBadDescriptor,	if the message argument is not a 16-bit descriptor.