core-lightning/wallet/db_sqlite3.c
Christian Decker d0027b1036 db: Implement basic query capabilities
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>
2019-09-05 23:41:05 +00:00

193 lines
4.6 KiB
C

#include <wallet/db_common.h>
#include "gen_db_sqlite3.c"
#include <ccan/ccan/tal/str/str.h>
#include <lightningd/log.h>
#include <sqlite3.h>
#include <stdio.h>
#if HAVE_SQLITE3
static const char *db_sqlite3_expand(struct db_stmt *stmt)
{
#if HAVE_SQLITE3_EXPANDED_SQL
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
const char *sql;
char *expanded_sql;
expanded_sql = sqlite3_expanded_sql(s);
sql = tal_strdup(stmt, expanded_sql);
sqlite3_free(expanded_sql);
return sql;
#else
return NULL;
#endif
}
static const char *db_sqlite3_fmt_error(struct db_stmt *stmt)
{
return tal_fmt(stmt, "%s: %s: %s", stmt->location, stmt->query->query,
sqlite3_errmsg(stmt->db->conn));
}
static bool db_sqlite3_query(struct db_stmt *stmt)
{
sqlite3_stmt *s;
sqlite3 *conn = (sqlite3*)stmt->db->conn;
int err;
err = sqlite3_prepare_v2(conn, stmt->query->query, -1, &s, NULL);
for (size_t i=0; i<stmt->query->placeholders; i++) {
struct db_binding *b = &stmt->bindings[i];
/* sqlite3 uses printf-like offsets, we don't... */
int pos = i+1;
switch (b->type) {
case DB_BINDING_UNINITIALIZED:
db_fatal("DB binding not initialized: position=%zu, "
"query=\"%s\n",
i, stmt->query->query);
case DB_BINDING_UINT64:
sqlite3_bind_int64(s, pos, b->v.u64);
break;
case DB_BINDING_INT:
sqlite3_bind_int(s, pos, b->v.i);
break;
case DB_BINDING_BLOB:
sqlite3_bind_blob(s, pos, b->v.blob, b->len,
SQLITE_TRANSIENT);
break;
case DB_BINDING_TEXT:
sqlite3_bind_text(s, pos, b->v.text, b->len,
SQLITE_TRANSIENT);
break;
case DB_BINDING_NULL:
sqlite3_bind_null(s, pos);
break;
}
}
if (err != SQLITE_OK) {
tal_free(stmt->error);
stmt->error = db_sqlite3_fmt_error(stmt);
return false;
}
stmt->inner_stmt = s;
return true;
}
static bool db_sqlite3_exec(struct db_stmt *stmt)
{
int err;
if (!db_sqlite3_query(stmt)) {
/* If the prepare step caused an error we hand it up. */
return false;
}
err = sqlite3_step(stmt->inner_stmt);
if (err != SQLITE_DONE) {
tal_free(stmt->error);
stmt->error = db_sqlite3_fmt_error(stmt);
return false;
}
return true;
}
static bool db_sqlite3_step(struct db_stmt *stmt)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_step(s) == SQLITE_ROW;
}
static bool db_sqlite3_begin_tx(struct db *db)
{
int err;
char *errmsg;
err = sqlite3_exec(db->conn, "BEGIN TRANSACTION;", NULL, NULL, &errmsg);
if (err != SQLITE_OK) {
db->error = tal_fmt(db, "Failed to begin a transaction: %s", errmsg);
return false;
}
return true;
}
static bool db_sqlite3_commit_tx(struct db *db)
{
int err;
char *errmsg;
err = sqlite3_exec(db->conn, "COMMIT;", NULL, NULL, &errmsg);
if (err != SQLITE_OK) {
db->error = tal_fmt(db, "Failed to begin a transaction: %s", errmsg);
return false;
}
return true;
}
static bool db_sqlite3_column_is_null(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_type(s, col) == SQLITE_NULL;
}
static u64 db_sqlite3_column_u64(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_int64(s, col);
}
static s64 db_sqlite3_column_int(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_int(s, col);
}
static size_t db_sqlite3_column_bytes(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_bytes(s, col);
}
static const void *db_sqlite3_column_blob(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_blob(s, col);
}
static const unsigned char *db_sqlite3_column_text(struct db_stmt *stmt, int col)
{
sqlite3_stmt *s = (sqlite3_stmt*)stmt->inner_stmt;
return sqlite3_column_text(s, col);
}
static void db_sqlite3_stmt_free(struct db_stmt *stmt)
{
if (stmt->inner_stmt)
sqlite3_finalize(stmt->inner_stmt);
stmt->inner_stmt = NULL;
}
struct db_config db_sqlite3_config = {
.name = "sqlite3",
.queries = db_sqlite3_queries,
.num_queries = DB_SQLITE3_QUERY_COUNT,
.expand_fn = &db_sqlite3_expand,
.exec_fn = &db_sqlite3_exec,
.query_fn = &db_sqlite3_query,
.step_fn = &db_sqlite3_step,
.begin_tx_fn = &db_sqlite3_begin_tx,
.commit_tx_fn = &db_sqlite3_commit_tx,
.stmt_free_fn = &db_sqlite3_stmt_free,
.column_is_null_fn = &db_sqlite3_column_is_null,
.column_u64_fn = &db_sqlite3_column_u64,
.column_int_fn = &db_sqlite3_column_int,
.column_bytes_fn = &db_sqlite3_column_bytes,
.column_blob_fn = &db_sqlite3_column_blob,
.column_text_fn = &db_sqlite3_column_text,
};
AUTODATA(db_backends, &db_sqlite3_config);
#endif