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#include "stdafx.h"
#include "SQL.h"
#include "Exception.h"
namespace sql {
/**
* Bind helpers.
*/
void bind(Statement *to, Nat pos, MAYBE(Str *) str) {
if (str)
to->bind(pos, str);
else
to->bindNull(pos);
}
void bind(Statement *to, Nat pos, Maybe<Bool> v) {
if (v.any())
to->bind(pos, v.value());
else
to->bindNull(pos);
}
void bind(Statement *to, Nat pos, Maybe<Int> v) {
if (v.any())
to->bind(pos, v.value());
else
to->bindNull(pos);
}
void bind(Statement *to, Nat pos, Maybe<Long> v) {
if (v.any())
to->bind(pos, v.value());
else
to->bindNull(pos);
}
void bind(Statement *to, Nat pos, Maybe<Float> v) {
if (v.any())
to->bind(pos, v.value());
else
to->bindNull(pos);
}
void bind(Statement *to, Nat pos, Maybe<Double> v) {
if (v.any())
to->bind(pos, v.value());
else
to->bindNull(pos);
}
/**
* Statement.
*/
Statement::Statement(DBConnection *connection) : resultAliveCount(0), resultSequence(0) {
connection->statements->putRaw(reinterpret_cast<TObject *>(this));
}
void Statement::invalidateResult() {
atomicIncrement(resultSequence);
atomicWrite(resultAliveCount, 0);
}
void Statement::deregister(DBConnection *c) {
c->statements->removeRaw(reinterpret_cast<TObject *>(this));
}
Statement::Statement(const Statement &o) {
throw new (this) SQLError(new (this) Str(S("Can not copy a prepared statement.")));
}
void Statement::deepCopy(CloneEnv *env) {
throw new (this) SQLError(new (this) Str(S("Can not move a prepared statement across thread boundaries.")));
}
/**
* Statement result.
*
* Note: We use atomics to update the shared data in Statement. This is mostly to be able to be
* somewhat robust against the case where the API is misused from multiple threads. The
* implementation is not thread-safe (there are cases where we will fail), but as this is mostly
* a safeguard to be able to detect such cases, it is fine.
*/
Statement::Result::Result(Statement *stmt) : owner(stmt), sequence(atomicRead(stmt->resultSequence)) {
atomicIncrement(owner->resultAliveCount);
}
Statement::Result::~Result() {
if (atomicRead(owner->resultSequence) == sequence) {
if (atomicDecrement(owner->resultAliveCount) == 0) {
owner->disposeResult();
}
}
}
Statement::Result::Result(const Result &other) : owner(other.owner), sequence(other.sequence) {
if (atomicRead(owner->resultSequence) == sequence) {
atomicIncrement(owner->resultAliveCount);
}
}
Statement::Result &Statement::Result::operator =(const Result &other) {
if (this == &other)
return *this;
Result tmp(other);
std::swap(owner, tmp.owner);
std::swap(sequence, tmp.sequence);
return *this;
}
Maybe<Row> Statement::Result::next() {
if (atomicRead(owner->resultSequence) != sequence)
return Maybe<Row>();
return owner->nextRow();
}
Int Statement::Result::lastRowId() const {
if (atomicRead(owner->resultSequence) != sequence)
return -1;
return owner->lastRowId();
}
Nat Statement::Result::changes() const {
if (atomicRead(owner->resultSequence) != sequence)
return 0;
return owner->changes();
}
void Statement::Result::finalize() {
if (atomicRead(owner->resultSequence) == sequence)
owner->disposeResult();
}
void Statement::Result::deepCopy(CloneEnv *env) {
throw new (env) SQLError(new (env) Str(S("Deep copies of database iterators are not supported.")));
}
/**
* Connection.
*/
DBConnection::DBConnection() {
statements = new (this) WeakSetBase();
cachedStatements = new (this) RefMap<CachedQuery *, Statement *>();
}
DBConnection::DBConnection(const DBConnection &o) {
throw new (this) SQLError(new (this) Str(S("Can not copy a database connection.")));
}
void DBConnection::deepCopy(CloneEnv *env) {
throw new (this) SQLError(new (this) Str(S("Can not move a database connection across thread boundaries.")));
}
Statement *DBConnection::prepare(QueryStr *query) {
return prepare(query->generate(visitor()));
}
Statement *DBConnection::prepare(CachedQuery *cached) {
Statement *out = cachedStatements->get(cached, null);
if (!out) {
out = cached->query(this);
cachedStatements->put(cached, out);
}
return out;
}
void DBConnection::close() {
// Note: We could close all 'cachedStatements' also, but those should all be in 'statements'
// anyway, so we can just clear it here.
cachedStatements->clear();
WeakSetBase::Iter iter(statements);
// Note: We know that everything that comes to us from the set will be alive and not finalized.
while (RootObject *stmt = iter.nextRaw()) {
reinterpret_cast<Statement *>(stmt)->finalize();
}
}
}
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