wchar_t_net_size- calculates the necessary buffer size for conversion of international character data from a local code set to a network code set
void wchar_t_net_size( rpc_binding_handle_t binding, unsigned32 network_code_set_value, unsigned32 local_buffer_size, idl_cs_convert_t *conversion_type, unsigned32 *network_buffer_size, error_status_t *status);
- Specifies the target binding handle from which to obtain buffer size evaluation information. When called from the client stub, this value is the binding handle of a compatible server returned by the rpc_ns_binding_import_next() or rpc_ns_binding_select() routine.
- The registered hexadecimal integer value that represents the code set to be used to transmit the character data over the network. In general, the network code set is the code set that the client application's code sets evaluation routine has determined to be compatible for this client and server. When the caller is the client stub, this value is the sending tag. When the caller is the server stub, this value is the receiving tag.
- The size, in units of wchar_t, of the buffer that is allocated for the international character data. For a conformant or conformant varying array, this value is the local value of the size_is variable for the array; that is, the value is the size of the marshalled string if no conversion is done.
- A pointer to the enumerated type defined in <dce/idlbase.h> that indicates whether data conversion is necessary and whether or not the existing buffer is sufficient for storing the results of the conversion. Because wchar_t and idl_byte require different numbers of bytes to encode one character, and wchar_t to idl_byte conversion always takes place, the conversion type returned is always idl_cs_new_buffer_convert.
- A pointer to the buffer size that must be allocated to contain the converted data, in units of idl_byte. This value is used as the network value of the size_is variable for the array, and is nonNULL only if a conformant or conformant varying array is to be marshalled. A value of NULL indicates that a fixed or varying array is to be marshalled.
- Returns the status code from this routine. This status code indicates whether the routine completed successfully or, if not, why not.
Possible status codes and their meanings include:
Conversion between code sets not possible.
If this error occurs in the server stub, an exception is raised to the client application.
The wchar_t_net_size() routine calculates the necessary buffer size for the conversion of international character data from a local code set to a network code set when wchar_t has been specified as the local data type. The routine is one of those used for character and code set interoperability, which permits clients and servers to transfer international character data in a heterogeneous character set and code sets environment.
The wchar_t_net_size() routine determines the type of conversion required and calculates the size of the necessary buffer, if a conformant or conformant varying array is to be marshalled; the calling stub then allocates a buffer of that size before it calls one of the code set conversion routines.
Applications do not call the wchar_t_net_size() routine directly; client and server stubs can call the routine before they marshall any data. Because wchar_t and idl_byte require different numbers of bytes to encode one character, wchar_t_net_size() always sets conversion_type to idl_cs_new_buffer_convert, regardless of whether it is called from a client or server stub, or whether client and server code set tag information has been stored in the binding handle by a code sets evaluation or tag-setting routine. If a conformant or conformant varying array is to be marshalled, the routine then calculates a new buffer size by multiplying the value of local_buffer_size by the number of bytes required to encode one wchar_t unit. The routine returns the new buffer size in the network_buffer_size argument. The size is specified in units of idl_byte, which is the network representation used for international character data.
When a fixed or varying array is being marshalled, the wchar_t_net_size() routine cannot calculate the required buffer size and does not return a value in the network_buffer_size argument.
When invoked from the server stub, this routine calls the routines dce_cs_loc_to_rgy() and rpc_rgy_get_max_bytes(). If either of these routines returns an error, the wchar_t_net_size() routine raises an exception to the client application.
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