The input adapter streams were input streams yielding either binary or
character data that could be constructed from a variable data source.
The stream would take care not to destroy the underlying data
source (i.e. not close it if it was a stream), so similar to with
FILE-PORTIONs, but simpler.
Unfortunately, the implementation was quite inefficient: They are
ultimately defined in terms of a function that retrieves the next
character in the source. This only allows for an implementation of
READ-CHAR (and READ-BYTE). Thanks to cl/8559, READ-SEQUENCE can be used
on e.g. FILE-PORTION, but this was still negated by a input adapter
based on one—then, READ-SEQUENCE would need to fall back on READ-CHAR or
READ-BYTE again.
Luckily, we can replace BINARY-INPUT-ADAPTER-STREAM and
CHARACTER-INPUT-ADAPTER-STREAM with a much simpler abstraction: Instead
of extra stream classes, we have a function, MAKE-INPUT-ADAPTER, which
returns an appropriate instance of FLEXI-STREAM based on a given source.
This way, the need for a distinction between binary and character input
adapter is eliminated, since FLEXI-STREAMS supports both binary and
character reads (external format is not yet handled, though).
Consequently, the :binary keyword argument to MIME-BODY-STREAM can be
dropped.
flexi-streams provides stream classes for everything except a stream
that doesn't close the underlying one. Since we have already implemented
this in POSITIONED-FLEXI-INPUT-STREAM, we can split this functionality
into a new superclass ADAPTER-FLEXI-INPUT-STREAM.
This change also allows addressing the performance regression
encountered in cl/8559: It seems that flexi-streams performs worse when
we are reading byte by byte or char by char. (After this change mblog is
still two times slower than on r/6150.) By eliminating the adapter
streams, we can start utilizing READ-SEQUENCE via decoding code that
supports it (i.e. qbase64) and bring performance on par with r/6150
again. Surely there are also ways to gain back even more performance
which has to be determined using profiling. Buffering more aggressively
seems like a sure bet, though.
Switching to flexi-streams still seems like a no-brainer, as it allows
us to drop a lot of code that was quite hacky (e.g. DELIMITED-INPUT-
STREAM) and implements en/decoding handling we did not support before,
but would need for improved correctness.
Change-Id: Ie2d1f4e42b47512a5660a1ccc0deeec2bff9788d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8581
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This refactor is driven by the following (ultimate) aims:
- Get rid of as much of the custom stream code in mime4cl which makes
less code to maintain in the future.
- Lay the groundwork for correct handling of 8bit transfer encoding:
The mime4cl we inherited assumes that any MIME message can be decoded
completely by the CL implementation (in SBCL's case using latin1)
into CHARACTERs. This is not necessarily the case. flexi-streams
allows changing how the stream is decoded on the fly and also has
support for reading the underlying bytes which is perfect for the
requirements decoding MIME has.
- Since flexi-streams uses trivial-gray-streams, it supports
READ-SEQUENCE. Taking advantage of this may improve decoding
performance significantly in the future.
This incurs the following changes:
- Naturally we now open given files as binary files in MIME-MESSAGE.
Given strings are encoded using STRING-TO-OCTETS and then passed on
to a new octet vector method. Instead of MY-STRING-INPUT-STREAM this
now uses flexi-streams' WITH-INPUT-FROM-SEQUENCE.
- OPEN-FILE-PORTION and OPEN-DECODED-FILE-PORTION need to be merged,
since the transfer encoding not only implies an extra decoder stream
that needs to be attached after file portion stream, but also imply a
certain encoding of the stream itself (mostly binary vs. ASCII).
As flexi-streams can change their encoding on the fly this could be
untangled again, but it is not strictly necessary.
As before, we use the DATA slot of the file portion to create a fresh
stream if possible. Instead of strings we now use an vector of octets
to match MIME-MESSAGE.
The actual portioned stream relies on POSITIONED-FLEXI-INPUT-STREAM, a
subclass of the stock FLEXI-INPUT-STREAM class, described below.
- POSITIONED-FLEXI-INPUT-STREAM replaces DELIMITED-INPUT-STREAM. It is
created using MAKE-POSITIONED-FLEXI-INPUT-STREAM which accepts the
same arguments as MAKE-FLEXI-STREAMS and, additionally, :IGNORE-CLOSE.
A POSITIONED-FLEXI-INPUT-STREAM works the same as an
FLEXI-INPUT-STREAM, but upon creation, the underlying stream is
rewinded or forwarded to the argument given by :POSITION using
FILE-POSITION.
If :IGNORE-CLOSE is T, a call to CLOSE is not forwarded to the
underlying stream.
Change-Id: I2d48c769bb110ca0b7cf52441bd63c1e1c2ccd04
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8559
Reviewed-by: sterni <sternenseemann@systemli.org>
Autosubmit: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This makes sure that initializing coder-stream-mixin (for the most part)
has the same interface as initializing qbase64:decode-stream. This will
make integrating that as a faster replacement to
mime4cl:base64-decoder-stream a bit easier.
The idea is to replace the char by char base64 decoder with one that
supports read-sequence. After that deliminited-input-stream needs to
gain support for read-sequence as well, so we can actually take
advantage of this fact. Finally, we'll have to evaluate the remaining
decoders and think about switching the (base64) encoders over as well.
Change-Id: If971da02437506e00a7c9fab2b94efc42725e62d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8555
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Autosubmit: sterni <sternenseemann@systemli.org>
The generic function itself needs to be defined using defgeneric,
defmethod is used for a defining method of a generic function, i.e. how
it should behave when confronted with a certain class.
Change-Id: Idd38afa02b56c5002e215decfff7f0c25267eab5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8532
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
SCLF is quite a big utility library (almost 3€ LOC) with limited
portability (CMUCL, SBCL and CLISP to an extent). Continuing to maintain
it is an unnecessary burden, as depot only uses a fraction of it which
is now inlined into the respective users (mime4cl and mblog).
In the future trimming down ex-sclf.lisp may make sense either by
refactoring the code that uses it or by moving interesting utilities
into e.g. klatre.
Change-Id: I2e73825b6bfa372e97847f25c30731a5aad4a1b5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5922
Tested-by: BuildkiteCI
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Accessing the headers of a MIME message feels like something mime4cl
should handle. We implemented this ad hoc in mblog before in order to
not need to worry about doing it in a sensible way. Now we introduce a
decent-ish interface for getting a header from a MIME message,
mime-message-header-values:
* It returns a list because MIME message headers may appear multiple
times.
* It decodes RFC2047 only upon request, as you may want to be stricter
about parsing certain fields.
* It checks header name equality case insensitively.
The code for decoding the RFC2047 string is retained and still uses
babel for doing the actual decoding.
Change-Id: I58bbbe4b46dbded04160b481a28a40d14775673d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5150
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Adds a simple generic function find-mime-text-part which returns the
first suitable text/* part in any MIME part it is given.
Has no meaningful alternatives handling at the moment: It will pick the
first text part and doesn't allow specifying a preference.
Change-Id: Id9b113b3ef3ca1a575ce8f3582a4f85e30edfb43
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3379
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Used http://wcp.sdf-eu.org/software/mime4cl-20150207T211851.tbz (sha256
5a914669bba7561efe59a4fd0817204c07ad2add98b03ae206ef185ac04affb3).
Importing seems sensible since there's no upstream repo nor has their
been a release since 2015.
This is just an import commit, so the changes made to make it build are
more discoverable as their own commit.
Change-Id: I2ff28c3c7433abdf7857204bc89eaf9edc0b1cbc
Reviewed-on: https://cl.tvl.fyi/c/depot/+/3378
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
