EvmVarSet(3) — Subroutines

NAME

EvmVarSet, EvmVarGet, EvmVarRelease, EvmVarListGet, EvmVarListFree − Manipulates event variables

LIBRARY

EVM Support Library (libevm.so, libevm.a)

SYNOPSIS

#include <evm/evm.h>

EvmStatus_t EvmVarSet(
        EvmEvent_t event,
        EvmVarName_t v_name,
        EvmVarType_t type,
        EvmVarValue_t item_value,
        EvmI18NMsgId_t msg_id,
        EvmSize_t size);

EvmStatus_t EvmVarGet(
        EvmEvent_t event,
        EvmVarName_t v_name,
        EvmVarStruct_t ∗var);

EvmStatus_t EvmVarRelease(
EvmVarStruct_t ∗var);

EvmStatus_t EvmVarListGet(
        EvmEvent_t event,
        EvmCount_t ∗var_count,
        EvmVarList_t ∗varList);

EvmStatus_t EvmVarListFree(
EvmVarList_t varlist);

OPERANDS

eventThe event to be processed.

v_nameThe name of a variable in the event for which data is to be set or obtained.

For EvmVarSet(), if the named variable exists, the associated data is modified. If the variable does not exist, it is created and added to the event. The value to be stored is passed in item_value.

typeThe enumeration constant for the type of the item_value to be stored in the variable indicated by v_name. Possible values for this field are as follows:

EvmTYPE_BOOLEAN

EvmTYPE_CHAR

EvmTYPE_INT16

EvmTYPE_INT32

EvmTYPE_INT64

EvmTYPE_UINT8

EvmTYPE_UINT16

EvmTYPE_UINT32

EvmTYPE_UINT64

EvmTYPE_FLOAT

EvmTYPE_DOUBLE

EvmTYPE_STRING

EvmTYPE_OPAQUE

item_valueThe value to be stored in the variable indicated by v_name.

msg_idFor a string variable being set in an internationalized event, this argument may contain an I18N message identifier corresponding to the value of the variable. The identifier must refer to a message in the catalog and message set associated with the event (see the EvmItemSet(3) reference page). This parameter is ignored for variables whose type is not EvmTYPE_STRING.

sizeThe size of the associated item_value in bytes. The caller must specify the correct size when setting a variable with a type of type EvmTYPE_OPAQUE. For all other variable types, the size is ignored.

varFor the EvmVarGet() routine, this is a pointer to the location where the output data is to be stored.

For the EvmVarRelease() routine, this is a pointer to the storage space to be released.

var_countThis is the number of names in the var_list obtained by EvmVarListGet(), not including the terminating NULL pointer.

varlistOn return from the EvmVarListGet() routine, this is a list of pointers to the names of the variables associated with the event. The last item in the list is a NULL pointer.

For the EvmVarListFree() routine, this is a list of names of variables for which memory should be freed. The list must be terminated by a NULL pointer.

DESCRIPTION

The EvmVarSet() routine sets the value of a variable data item, indicated by v_name, in an event. This routine is used both for adding a variable and for altering its value. If the v_name variable is not already present in the event, it is added.

The EvmVarGet() routine returns the event variable indicated by v_name in the var variable. The caller must free any space used by the variable by calling EvmVarRelease().

The EvmVarRelease() routine releases any storage space that was allocated when the specified var was retrieved from an event using EvmVarGet(). It is important that this routine is called when the variable is no longer needed, to ensure that all memory associated with the variable is released.

The EvmVarListGet() routine returns, in the varList reference argument, a pointer to an array of pointers to names of all the variables contained in the event. The last entry in the array is a NULL pointer. The var_count argument receives the number of names in the list, not counting the terminating null value. The caller must free the memory used by the list by calling EvmVarListFree().

The EvmVarListFree() routine frees the memory used by a variable list (varList).

NOTES

The caller must specify the size when adding an opaque variable to an event.

RESTRICTIONS

To avoid memory leakage, memory which is supplied to the caller from API routines must be freed with the appropriate EVM API free routine.

RETURN VALUES

EvmERROR_NONE
The operation was completed without error.

EvmERROR_INVALID_ARGUMENT
One of the arguments to the function was invalid.

EvmERROR_INVALID_VALUE
A value in a structure member is invalid.

EvmERROR_NO_MEMORY
An operation failed because an attempt to acquire heap memory failed.

EvmERROR_NOT_PRESENT
A request specified an item or variable name component in an itemList or a varList that is not part of the event being processed.

ERRORS

None

FILES