core-lightning/db/utils.h
Rusty Russell 2971b2af79 bkpr: insert obscure 60s pop references.
The initial snapshots on an already-running lightningd are expected to
be unbalanced, but this shouldn't cause users to long for the green,
green grass of home.

This controls the Art of Noise.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2022-08-01 09:01:08 -07:00

101 lines
3.4 KiB
C

#ifndef LIGHTNING_DB_UTILS_H
#define LIGHTNING_DB_UTILS_H
#include "config.h"
#include <ccan/take/take.h>
#include <ccan/tal/tal.h>
struct db;
struct db_stmt;
size_t db_query_colnum(const struct db_stmt *stmt,
const char *colname);
/* Return next 'row' result of statement */
bool db_step(struct db_stmt *stmt);
/* TODO(cdecker) Remove the v2 suffix after finishing the migration */
#define db_prepare_v2(db,query) \
db_prepare_v2_(__FILE__ ":" stringify(__LINE__), db, query)
/**
* db_exec_prepared -- Execute a prepared statement
*
* After preparing a statement using `db_prepare`, and after binding all
* non-null variables using the `db_bind_*` functions, it can be executed with
* this function. It is a small, transaction-aware, wrapper around `db_step`,
* that calls fatal() if the execution fails. This may take ownership of
* `stmt` if annotated with `take()`and will free it before returning.
*
* If you'd like to issue a query and access the rows returned by the query
* please use `db_query_prepared` instead, since this function will not expose
* returned results, and the `stmt` can only be used for calls to
* `db_count_changes` and `db_last_insert_id` after executing.
*
* @stmt: The prepared statement to execute
*/
bool db_exec_prepared_v2(struct db_stmt *stmt TAKES);
/**
* db_query_prepared -- Execute a prepared query
*
* After preparing a query using `db_prepare`, and after binding all non-null
* variables using the `db_bind_*` functions, it can be executed with this
* function. This function must be called before calling `db_step` or any of
* the `db_col_*` column access functions.
*
* If you are not executing a read-only statement, please use
* `db_exec_prepared` instead.
*
* @stmt: The prepared statement to execute
*/
bool db_query_prepared(struct db_stmt *stmt);
size_t db_count_changes(struct db_stmt *stmt);
void db_report_changes(struct db *db, const char *final, size_t min);
void db_prepare_for_changes(struct db *db);
u64 db_last_insert_id_v2(struct db_stmt *stmt);
/**
* db_prepare -- Prepare a DB query/command
*
* Create an instance of `struct db_stmt` that encapsulates a SQL query or command.
*
* @query MUST be wrapped in a `SQL()` macro call, since that allows the
* extraction and translation of the query into the target SQL dialect.
*
* It does not execute the query and does not check its validity, but
* allocates the placeholders detected in the query. The placeholders in the
* `stmt` can then be bound using the `db_bind_*` functions, and executed
* using `db_exec_prepared` for write-only statements and `db_query_prepared`
* for read-only statements.
*
* @db: Database to query/exec
* @query: The SQL statement to compile
*/
struct db_stmt *db_prepare_v2_(const char *location, struct db *db,
const char *query_id);
/**
* db_open - Open or create a database
*/
struct db *db_open(const tal_t *ctx, const char *filename);
/**
* Report a statement that changes the wallet
*
* Allows the DB driver to report an expanded statement during
* execution. Changes are queued up and reported to the `db_write` plugin hook
* upon committing.
*/
void db_changes_add(struct db_stmt *db_stmt, const char * expanded);
void db_assert_no_outstanding_statements(struct db *db);
/**
* Access pending changes that have been added to the current transaction.
*/
const char **db_changes(struct db *db);
#endif /* LIGHTNING_DB_UTILS_H */