The only thing that needs ld->wallet after this is destroy_invoices_waiter (off jsonrpc)
Could not find any other destructors (destroy_*) that need wallet or db access after this.
Any db access would now segfault.
because:
- shutdown_subdaemons can trigger db write, comments in that function say so at least
- resurrecting the main event loop with subdaemons still running is counter productive
in shutting down activity (such as htlc's, hook_calls etc.)
- custom behavior injected by plugins via hooks should be consistent, see test
in previous commmit
IDEA:
in shutdown_plugins, when starting new io_loop:
- A plugin that is still running can return a jsonrpc_request response, this triggers
response_cb, which cannot be handled because subdaemons are gone -> so any response_cb should be blocked/aborted
- jsonrpc is still there, so users (such as plugins) can make new jsonrpc_request's which
cannot be handled because subdaemons are gone -> so new rpc_request should also be blocked
- But we do want to send/receive notifications and log messages (handled in jsonrpc as jsonrpc_notification)
as these do not trigger subdaemon calls or db_write's
Log messages and notifications do not have "id" field, where jsonrpc_request *do* have an "id" field
PLAN (hypothesis):
- hack into plugin_read_json_one OR plugin_response_handle to filter-out json with
an "id" field, this should
block/abandon any jsonrpc_request responses (and new jsonrpc_requests for plugins?)
Q. Can internal (so not via plugin) jsonrpc_requests called in the main io_loop return/revive in
the shutdown io_loop?
A. No. All code under lightningd/ returning command_still_pending depends on either a subdaemon, timer or
plugin. In shutdown loop the subdaemons are dead, timer struct cleared and plugins will be taken
care of (in next commits).
fixup: we can only io_break the main io_loop once
This simplistically maps names to numbers, eg:
SELECT foo, bar FROM tbl;
'foo' -> 0
'bar' -> 1
If a statement is too complex for our simple parsing, we treat it as a
single field (which currently it always is).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is particularly useful after our recent field deletion:
before: 362,573,824 bytes
after: 124,190,720 bytes
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Changed: db: removal of old HTLC information and vacuuming shrinks large lightningd.sqlite3 by a factor of 2-3.
This increments the `data_version` upon committing dirty transactions, reads
the last data_version upon startup, and tracks the number in memory in
parallel to the DB (see next commit for rationale).
Changelog-Changed: JSON-RPC: Added a `data_version` field to the `db_write` hook which returns a numeric transaction counter.
Using a generated identifier with filename and line proved to be brittle since
compilers assign the __LINE__ macro differently on multi-line macro
invocations.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
We used to do some of the setup work in db.c, which is now free of any
sqlite3-specific code. In addition we also switch over to fully qualified DSNs
to specify the location of the wallet.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
It's better to let the driver decide when and how to expand. It can then
report the expanded statement back to the dispatch through the
`db_changes_add` function.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
We now have a much stronger consistency check from the combination of
transaction wrapping, tal memory leak detection. Tramsaction wrapping ensures
that each statement is executed before the transaction is committed. The
commit is also driven by the `io_loop`, which means that it is no longer
possible for us to have statements outside of transactions and transactions
are guaranteed to commit at the round's end.
By adding the tal-awareness we can also get a much better indication as to
whether we have un-freed statements flying around, which we can test at the
end of the round as well.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
This is likely the last part we need to completely encapsulate the part of the
sqlite3 API that we were using. Like the `db_count_changes` call I decided to
pass in the `struct db_stmt` since really they refer to the statement that was
executed and not the db.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
These are used to do one-time initializations and wait for pending statements
before closing.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
I was hoping to get rid of these by using "ON CONFLICT" upserts, however
sqlite3 only started supporting them in version 3.24.0 which is newer than
some of our deployment targets.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
This is the first step towards being able to extract information from query
rows. Only the most basic types are exposed, the others will be built on top
of these primitives.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
For some of the query methods in the next step we need to have an idea of
whether the stmt was executed (db_step function) so let's track that
explicitly.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
This gets rid of the two parallel execution paths of read-only and write
queries, by explicitly stating with each query whether it is a read-only
query, we only need to remember the ones marked as write queries.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
All drivers will have to reach into it, so put it in a place that is reachable
from the drivers, along with all other definitions.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
This is the counterpart of the annotations we did in the last few commits. It
extracts queries, passes them through a driver-specific query rewriter and
dumps them into a driver-specific query-list, along with some metadata to
facilitate processing later on. The generated query list is then registered as
a `db_config` and will be loaded by the driver upon instantiation.
Signed-off-by: Christian Decker <decker.christian@gmail.com>
