lightning

History

Christian Decker 3f3a48dae9 db: Turn the transaction counter into an optimistic lock The optimistic lock prevents multiple instances of c-lightning making concurrent modifications to the database. That would be unsafe as it messes up the state in the DB. The optimistic lock is implemented by checking whether a gated update on the previous value of the `data_version` actually results in an update. If that's not the case the DB has been changed under our feet. The lock provides linearizability of DB modifications: if a database is changed under the feet of a running process that process will `abort()`, which from a global point of view is as if it had crashed right after the last successful commit. Any process that also changed the DB must've started between the last successful commit and the unsuccessful one since otherwise its counters would not have matched (which would also have aborted that transaction). So this reduces all the possible timelines to an equivalent where the first process died, and the second process recovered from the DB. This is not that interesting for `sqlite3` where we are also protected via the PID file, but when running on multiple hosts against the same DB, e.g., with `postgres`, this protection becomes important. Changelog-Added: DB: Optimistic logging prevents instances from running concurrently against the same database, providing linear consistency to changes.		5 years ago
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test	db: Track the data_version in the database	5 years ago
.gitignore	wallet: Create and manage a sqlite3 database for the wallet	8 years ago
Makefile	wallet/Makefile: fix dependency line.	5 years ago
db.c	db: Turn the transaction counter into an optimistic lock	5 years ago
db.h	db: Track the data_version in the database	5 years ago
db_common.h	db: Track the data_version in the database	5 years ago
db_postgres.c	db: Implement postgres driver primitives	5 years ago
db_sqlite3.c	db: Move remainder of the sqlite3 into the apropriate file	5 years ago
invoices.c	wallet: add invoice features into db.	5 years ago
invoices.h	wallet: add invoice features into db.	5 years ago
txfilter.c	elements: Fix transaction handling for elements transactions	5 years ago
txfilter.h	pubkey: rename PUBKEY_DER_LEN to PUBKEY_CMPR_LEN.	6 years ago
wallet.c	wallet: remove edgecase around transaction checks	5 years ago
wallet.h	wallet: remove edgecase around transaction checks	5 years ago
walletrpc.c	bitcoind: remove the chainparams member	5 years ago
walletrpc.h	Use expected LIGHTNING_DIR_FILE_H define	7 years ago