Error Handling

Error handling for L4 object invocation. More...

Collaboration diagram for Error Handling:

Enumerations
enum	l4_ipc_tcr_error_t {   L4_IPC_ERROR_MASK = 0x1F , L4_IPC_SND_ERR_MASK = 0x01 , L4_IPC_ENOT_EXISTENT = 0x04 , L4_IPC_RETIMEOUT = 0x03 ,   L4_IPC_SETIMEOUT = 0x02 , L4_IPC_RECANCELED = 0x07 , L4_IPC_SECANCELED = 0x06 , L4_IPC_REMAPFAILED = 0x11 ,   L4_IPC_SEMAPFAILED = 0x10 , L4_IPC_RESNDPFTO = 0x0b , L4_IPC_SESNDPFTO = 0x0a , L4_IPC_RERCVPFTO = 0x0d ,   L4_IPC_SERCVPFTO = 0x0c , L4_IPC_REABORTED = 0x0f , L4_IPC_SEABORTED = 0x0e , L4_IPC_REMSGCUT = 0x09 ,   L4_IPC_SEMSGCUT = 0x08 }
	Error codes in the error TCR. More...

Functions
l4_umword_t	l4_ipc_error (l4_msgtag_t tag, l4_utcb_t *utcb) L4_NOTHROW
	Get the IPC error code for an IPC operation.
long	l4_error (l4_msgtag_t tag) L4_NOTHROW
	Get IPC error code if any or message tag label otherwise for an IPC call.
int	l4_ipc_is_snd_error (l4_utcb_t *utcb) L4_NOTHROW
	Returns whether an error occurred in send phase of an invocation.
int	l4_ipc_is_rcv_error (l4_utcb_t *utcb) L4_NOTHROW
	Returns whether an error occurred in receive phase of an invocation.
int	l4_ipc_error_code (l4_utcb_t *utcb) L4_NOTHROW
	Get the error condition of the last invocation from the TCR.

Detailed Description

Error handling for L4 object invocation.

Include File

#include <l4/sys/ipc.h> 

Enumeration Type Documentation

l4_ipc_tcr_error_t

enum l4_ipc_tcr_error_t

Error codes in the error TCR.

The error codes are accessible via the error TCR, see l4_thread_regs_t.error.

Enumerator
L4_IPC_ERROR_MASK	Mask for error bits.
L4_IPC_SND_ERR_MASK	Send error mask.
L4_IPC_ENOT_EXISTENT	Non-existing destination or source.
L4_IPC_RETIMEOUT	Timeout during receive operation.
L4_IPC_SETIMEOUT	Timeout during send operation.
L4_IPC_RECANCELED	Receive operation canceled.
L4_IPC_SECANCELED	Send operation canceled.
L4_IPC_REMAPFAILED	Map flexpage failed in receive operation.
L4_IPC_SEMAPFAILED	Map flexpage failed in send operation.
L4_IPC_RESNDPFTO	Send-pagefault timeout in receive operation.
L4_IPC_SESNDPFTO	Send-pagefault timeout in send operation.
L4_IPC_RERCVPFTO	Receive-pagefault timeout in receive operation.
L4_IPC_SERCVPFTO	Receive-pagefault timeout in send operation.
L4_IPC_REABORTED	Receive operation aborted.
L4_IPC_SEABORTED	Send operation aborted.
L4_IPC_REMSGCUT	Received message truncated. Usually returned when the typed items to be sent by the IPC partner exceed the buffer registers of the respective types.
L4_IPC_SEMSGCUT	Sent message truncated. Usually returned when the typed items to be sent exceed the IPC partner’s buffer registers of the respective types.

Definition at line 92 of file ipc.h.

Function Documentation

l4_error()

long l4_error ( l4_msgtag_t  tag )

inline

Get IPC error code if any or message tag label otherwise for an IPC call.

This function shall only be used if the IPC operation includes a receive phase (usually a call operation), otherwise no tag label is received and the return value of this function is undefined.

Parameters

tag	Message tag returned by the IPC call.

Returns

In case of an IPC error, a negative error code in the range of L4_EIPC_LO to L4_EIPC_HI (see l4_ipc_to_errno() and l4_ipc_tcr_error_t), otherwise the tag label. By convention, the callee can signal errors via a negative tag label (negated value from l4_error_code_t) and success via a non-negative value.

Examples

examples/libs/l4re/streammap/client.cc, examples/sys/aliens/main.c, examples/sys/isr/main.c, examples/sys/migrate/thread_migrate.cc, examples/sys/singlestep/main.c, examples/sys/start-with-exc/main.c, and examples/sys/utcb-ipc/main.c.

Definition at line 657 of file ipc.h.

References l4_utcb().

Referenced by L4Re::Mem_alloc::alloc(), L4virtio::Driver::Device::bind_notification_irq(), L4::cap_dynamic_cast(), L4virtio::Driver::Device::driver_connect(), fiasco_tbuf_log(), fiasco_tbuf_log_3val(), fiasco_tbuf_log_binary(), L4Re::Util::Event_t< PAYLOAD >::init(), l4_vcon_write_u(), and L4Re::Util::Event_buffer_consumer_t< PAYLOAD >::process().

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l4_ipc_error()

l4_umword_t l4_ipc_error ( l4_msgtag_t  tag, l4_utcb_t *  utcb  )

inline

Get the IPC error code for an IPC operation.

Parameters

tag	Message tag returned by the IPC operation.
utcb	UTCB that was used for the IPC operation.

Returns

0 if no error condition is set, error code otherwise (see l4_ipc_tcr_error_t).

Examples

examples/sys/ipc/ipc_example.c, and examples/sys/start-with-exc/main.c.

Definition at line 640 of file ipc.h.

References l4_thread_regs_t::error, L4_IPC_ERROR_MASK, L4_LIKELY, and l4_msgtag_has_error().

Referenced by l4util_ioport_map(), L4Re::Util::Event_buffer_consumer_t< PAYLOAD >::process(), and L4virtio::Driver::Device::wait().

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l4_ipc_error_code()

int l4_ipc_error_code ( l4_utcb_t *  utcb )

inline

Get the error condition of the last invocation from the TCR.

Precondition

l4_msgtag_has_error(tag) == true

Parameters

utcb	UTCB to check.

Returns

Error condition of type l4_ipc_tcr_error_t.

Definition at line 669 of file ipc.h.

References l4_thread_regs_t::error, and L4_IPC_ERROR_MASK.

l4_ipc_is_rcv_error()

int l4_ipc_is_rcv_error ( l4_utcb_t *  utcb )

inline

Returns whether an error occurred in receive phase of an invocation.

Precondition

l4_msgtag_has_error(tag) == true

Parameters

utcb	UTCB to check.

Returns

Boolean value.

Definition at line 666 of file ipc.h.

References l4_thread_regs_t::error.

l4_ipc_is_snd_error()

int l4_ipc_is_snd_error ( l4_utcb_t *  utcb )

inline

Returns whether an error occurred in send phase of an invocation.

Precondition

l4_msgtag_has_error(tag) == true

Parameters

utcb	UTCB to check.

Returns

Boolean value.

Definition at line 663 of file ipc.h.