it was used by iOS to know when a background fetch was complete;
meanwhile the superiour `dc_accounts_background_fetch()` is used for
that.
there is still the corresponding context function `dc_all_work_done()`,
this not used by any UI as well, however, it is in use by a python
tests.
not sure, what to do with it, at a first glance, the test still seems
useful.
Even though r2d2 connection pool is removed,
deleting accounts still fails in Windows CI.
This reverts commit e88f21c010.
`try_many_times` documentation is modified to explain
why the workaround is still needed.
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.
To handle backups the UIs have to make sure they do stop the IO
scheduler and also don't accidentally restart it while working on it.
Since they have to call start_io from a bunch of locations this can be
a bit difficult to manage.
This introduces a mechanism for the core to pause IO for some time,
which is used by the imex function. It interacts well with other
calls to dc_start_io() and dc_stop_io() making sure that when resumed
the scheduler will be running or not as the latest calls to them.
This was a little more invasive then hoped due to the scheduler. The
additional abstraction of the scheduler on the context seems a nice
improvement though.
All contexts created by the same account manager
share stock string translations. Setting translation on
a single context automatically sets translations for all other
accounts, so it is enough to set translations on the active account.
This allows account manager to construct a single event channel and
inject it into all created contexts instead of aggregating events from
separate event emitters.
When removing an account, try 60 times with 1 second sleep in between
in case removal of database files fails. This happens on Windows
platform sometimes due to a known bug in r2d2 which may result in 30
seconds delay until all connections are closed [1].
[1] https://github.com/sfackler/r2d2/issues/99
To create encrypted account with account manager, call
dc_accounts_add_closed_account(). Open this account with
dc_context_open() using the passphrase you want to use for encryption.
When application is loaded next time and account manager is created,
it will open all accounts that have no passphrase set. For encrypted
accounts dc_context_is_open() will return 0. To open them, call
dc_context_open() with the correct passphrase. After opening, call
dc_context_start_io() on this account or just dc_accounts_start_io()
to start all accounts that are not started yet.
Support for legacy SQLite-based backup format is removed in this
commit.
