The asn1_compiler process is particularly chatty and produces
about the only stdout output for an allmodconfig kernel.
In order to follow the general concept of 'no news is good
news' for building kernels, this hides all the existing output
unless the KBUILD_VERBOSE environment variable is set.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Add a simple ASN.1 grammar compiler. This produces a bytecode output that can
be fed to a decoder to inform the decoder how to interpret the ASN.1 stream it
is trying to parse.
Action functions can be specified in the grammar by interpolating:
({ foo })
after a type, for example:
SubjectPublicKeyInfo ::= SEQUENCE {
algorithm AlgorithmIdentifier,
subjectPublicKey BIT STRING ({ do_key_data })
}
The decoder is expected to call these after matching this type and parsing the
contents if it is a constructed type.
The grammar compiler does not currently support the SET type (though it does
support SET OF) as I can't see a good way of tracking which members have been
encountered yet without using up extra stack space.
Currently, the grammar compiler will fail if more than 256 bytes of bytecode
would be produced or more than 256 actions have been specified as it uses
8-bit jump values and action indices to keep space usage down.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
