Opening the same account (context) from multiple processes is dangerous, can result in duplicate
downloads of the same message etc. Same for account manager, attempts to modify the same
accounts.toml even if done atomically with may result in corrupted files as atomic replacement
procedure does not expect that multiple processes may write to the same temporary file.
accounts.toml cannot be used as a lockfile because it is replaced during atomic update. Therefore, a
new file next to accounts.toml is needed to prevent starting second account manager in the same
directory.
But iOS needs to be able to open accounts from multiple processes at the same time. This is required
as the "share-to-DC extension" is a separate process by iOS design -- this process may or may not be
started while the main app is running. Accounts are not altered however by this extension, so let's
add to the `Accounts::new()` constructor an `rdwr` parameter which allows to read the accounts
config w/o locking the lockfile.
Message.set_text() and Message.get_text() are modified accordingly
to accept String and return String.
Messages which previously contained None text
are now represented as messages with empty text.
Use Message.set_text("".to_string())
instead of Message.set_text(None).
This way is more compatible to JSON-RPC libraries
that do not support receiving notifications from the server
and allows describing event types in the OpenRPC specification.
Event thread converting events to notifications in the FFI
is removed, so it is now possible to construct a dc_jsonrpc_instance_t
while still retrieving events via dc_event_emitter_t.
This patch adds new C APIs
dc_get_next_msgs() and dc_wait_next_msgs(),
and their JSON-RPC counterparts
get_next_msgs() and wait_next_msgs().
New configuration "last_msg_id"
tracks the last message ID processed by the bot.
get_next_msgs() returns message IDs above
the "last_msg_id".
wait_next_msgs() waits for new message notification
and calls get_next_msgs().
wait_next_msgs() can be used to build
a separate message processing loop
independent of the event loop.
Async Python API get_fresh_messages_in_arrival_order()
is deprecated in favor of get_next_messages().
Introduced Python APIs:
- Account.wait_next_incoming_message()
- Message.is_from_self()
- Message.is_from_device()
Introduced Rust APIs:
- Context.set_config_u32()
- Context.get_config_u32()
This removes the message that needed to be supplied to LogExt::log_err
calls. This was from a time before we adopted anyhow and now we are
better off using anyhow::Context::context for the message: it is more
consistent, composes better and is less custom.
The benefit of the composition can be seen in the FFI calls which need
to both log the error as well as return it to the caller via
the set_last_error mechanism.
It also removes the LogExt::ok_or_log_msg funcion for the same reason,
the message is obsoleted by anyhow's context.
The documentation says this blocks. This should block because it also
means the error reporting is more accurate by calling set_last_error
just before returning.
Otherwise it is possible for the context that is used in the spawn to
be unreferenced. Really this should be caught by the borrow checker
that ensures we only spawn things with a 'static lifetime, but we're
handling raw pointers so it doesn't.
This adds a result extension trait to explicitly set the last error,
which *should* be the default for the FFI. Currently not touching all
APIs since that's potentially disruptive and we're close to a release.
The logging story is messy, as described in the doc comment. We
should further clean this up and tidy up these APIs so it's more
obvious to people how to do the right thing.
This fixes use-after-free in case dc_context_unref() is called
while the background process spawned by dc_configure() is still
running.
Corresponding regression test in Python can be run with
`pytest tests/test_1_online.py::test_configure_unref`.
