asn1rt - ASN.1 runtime support functions

This module is the interface module for the ASN.1 runtime support functions. To encode and decode ASN.1 types in runtime the functions in this module should be used.

encode(Module,Type,Value)-> {ok,BinOrList} | {error,Reason}

Types

Module = Type = atom()

Value = term()

BinOrList = Bytes | binary()

Bytes = [Int|binary|Bytes] when integer(Int), Int >= 0, Int =< 255

Reason = term()

Encodes Value of Type defined in the ASN.1 module Module. Returns a possibly nested list of bytes and or binaries if successful. If Module was compiled with the options per_bin and optimize the result is a binary. To get as fast execution as possible the encode function only performs rudimentary tests that the input Value is a correct instance of Type. The length of strings is for example not always checked.

decode(Module,Type,Bytes) -> {ok,Value}|{error,Reason}

Types

Module = Type = atom()

Value = Reason = term()

Bytes = binary | [Int] when integer(Int), Int >= 0, Int =< 255 | binary

Decodes Type from Module from the list of bytes or binary Bytes. If the module is compiled with ber_bin or per_bin option Bytes must be a binary. Returns {ok, Value} if successful.

validate(Module,Type,Value) -> ok | {error,Reason}

Types

Module = Type = atom()

Value = term()

Validates that Value conforms to Type from Module. Not implemented in this version of the ASN.1 application.

load_driver() -> ok | {error,Reason}

Types

Reason = term()

This function loads the linked-in driver before the first call to encode. If this function is not called the driver will be loaded automatically at the first call to encode. If one doesn't want the performance cost of a driver load when the application is running, this function makes it possible to load the driver in an initialization.

The driver is only used when encoding/decoding ASN.1 files that were compiled with the options per_bin and optimize.

unload_driver() -> ok | {error,Reason}

Types

Reason = term()

This function unloads the linked-in driver. When the driver has been loaded it remains in the environment until it is unloaded. Normally the driver should remain loaded, it is crucial for the performance of ASN.1 encoding.

The driver is only used when ASN.1 modules have been compiled with the flags per_bin and optimize.

info(Module) -> {ok,Info} | {error,Reason}

Types

Module = atom()

Info = list()

Reason = term()

info/1 returns the version of the asn1 compiler that was used to comile the module. It also returns the compiler options that was used.

utf8_binary_to_list(UTF8Binary) -> {ok,UnicodeList} | {error,Reason}

Types

UTF8Binary = binary()

UnicodeList = [integer()]

Reason = term()

utf8_binary_to_list/1 Transforms a UTF8 encoded binary to a list of integers, where each integer represents one character as its unicode value. The function fails if the binary is not a properly encoded UTF8 string.

utf8_list_to_binary(UnicodeList) -> {ok,UTF8Binary} | {error,Reason}

Types

UnicodeList = [integer()]

UTF8Binary = binary()

Reason = term()

utf8_list_to_binary/1 Transforms a list of integers, where each integer represents one character as its unicode value, to a UTF8 encoded binary.

Kenneth Lundin - support@erlang.ericsson.se
Bertil Karlsson - support@erlang.ericsson.se