This module provides a base64 encodear and decoder. Use
require("base64") to load it.
Accumulate data to be base64 decoded
_base64_decoder_accumulate(Base64_Type b64, String_Type data)
This routine adds a tring to the base64 decoder queue of the
specifed Base64_Type object, previously instantiated using the
_base64_decoder_new.
See the documentation for _base64_decoder_new for more
detailed usage.
_base64_decoder_new, _base64_decoder_close, _base64_encoder_new
Intantiate a new base64 decoder
Base64_Type _base64_decoder_new (Ref_Type func [,func_data])
This routine returns instantiates a Base64_Type decoder object that
may be used to decode base64 data. It require a single
Ref_Type parameter that is a reference to a callback function
that the decoder will call with with (partially) decoded data. The second
argument, func_data, is optional. If present it will also be
passed to the callback function.
The callback function must be defined to accept one or two
parameters, depending upon whether the _base64_decoder_new function
was called with the optional func_data argument. If
func_data was passed, then it will be passed as the first
argument to the callback function. The (partially) encoded string
is passed as the last argument. The callback function shall return
nothing.
The following example defines a function that base64-decodes a string.
private define decode_callback (strp, decoded_str)
{
@strp = @strp + decoded_str;
}
define b64decode_string (str)
{
variable b = ""B; % The decoded string is binary
variable b64 = _base64_decoder_new (&decode_callback, &b);
_base64_decoder_accumulate (b64, str);
_base64_decoder_close (b64);
return b;
}
The following example takes data from an input file pointer
fpin and writes the decoded data to an output file pointer
fpout:
private define decoder_callback (fpout, data)
{
() = fwrite (data, fpout);
}
define base64_decode_file (fpin, fpout)
{
variable b64 = _base64_decoder_new (&encoder_callback, fpout);
variable line;
while (-1 != fgets (&line, fpin))
_base64_decoder_accumulate (b64, line);
_base64_decoder_close (b64);
}
_base64_decoder_accumulate, _base64_decoder_close, _base64_encoder_new
Flush and delete a base64 decoder
_base64_decoder_close (Base64_Type b64)
This function must be called when there is no more data for the
specified base64 decoder to process. See the documentation for
_base64_decoder_new for additional information and usage.
_base64_decoder_new, _base64_decoder_accumulate, _base64_encoder_close
Accumulate data to be base64 encoded
_base64_encoder_accumulate(Base64_Type b64, BString_Type data)
This routine adds a binary string to the encoder queue of the
specifed Base64_Type object, previously instantiated using the
_base64_encoder_new.
See the documentation for _base64_encoder_new for more
detailed usage.
_base64_encoder_new, _base64_encoder_close, _base64_decoder_new
Intantiate a new base64 encoder
Base64_Type _base64_encoder_new (Ref_Type func [,func_data])
This routine returns instantiates a Base64_Type decoder object that
may be used to base64-encode data. It require a single
Ref_Type parameter that is a reference to a callback function
that the encoder will call with the data to be encoded. The second
argument, func_data, is optional. If present it will also be
passed to the callback function.
The callback function must be defined to accept one or two
parameters, depending upon whether the _base64_encoder_new function
was called with the optional func_data argument. If
func_data was passed, then it will be passed as the first
argument to the callback function. The (partially) encoded string
is passed as the last argument. The callback function shall return
nothing.
The following example defines a function that base64 encodes a string.
private define encode_callback (strp, encoded_str)
{
@strp = @strp + encoded_str;
}
define b64encode_string (bstr)
{
variable s = "";
variable b64 = _base64_encoder_new (&encode_callback, &s);
_base64_encoder_accumulate (b64, bstr);
_base64_encoder_close (b64);
return b;
}
The following example takes data from an input file pointer
fpin and writes the encoded data to an output file pointer
fpout:
private define encoder_callback (fpout, encoded_data)
{
() = fputs (encoded_data, fpout);
}
define define base64_encode_file (fpin, fpout)
{
variable b64 = _base64_encoder_new (&encoder_callback, fpout);
variable bytes;
while (-1 != fread_bytes (&bytes, 512, fpin))
_base64_encoder_accumulate (b64, bytes);
_base64_encoder_close (b64);
}
_base64_encoder_accumulate, _base64_encoder_close, _base64_decoder_new
Flush and delete a base64 encoder
_base64_encoder_close (Base64_Type b64)
This function must be called when there is no more data for the
specified base64 encoder to process. See the documentation for
_base64_encoder_new for additional information and usage.
_base64_encoder_new, _base64_encoder_accumulate, _base64_decoder_close