Bug 591447 - Cookie rowids may collide if PR_Now() winds backward. Part 4: delete expired cookies on migrate. r=sdwilsh, a=betaN+

This commit is contained in:
Dan Witte 2010-10-19 17:24:53 -07:00
parent 68ea23abd0
commit b17354e38b

View File

@ -826,42 +826,87 @@ nsCookieService::TryInitDB(PRBool aDeleteExistingDB)
case 3:
{
// Add the creationTime column to the table, and create a unique index
// on (name, host, path). Before we do this, we have to purge the table
// of expired cookies such that we know that the (name, host, path)
// index is truly unique -- otherwise we can't create the index. Note
// that we can't just execute a statement to delete all rows where the
// expiry column is in the past -- doing so would rely on the clock
// (both now and when previous cookies were set) being monotonic.
// Select the whole table, and order by the fields we're interested in.
// This means we can simply do a linear traversal of the results and
// check for duplicates as we go.
nsCOMPtr<mozIStorageStatement> select;
rv = mDBState->dbConn->CreateStatement(NS_LITERAL_CSTRING(
"SELECT id, name, host, path FROM moz_cookies "
"ORDER BY name ASC, host ASC, path ASC, expiry ASC"),
getter_AddRefs(select));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<mozIStorageStatement> deleteExpired;
rv = mDBState->dbConn->CreateStatement(NS_LITERAL_CSTRING(
"DELETE FROM moz_cookies WHERE id = :id"),
getter_AddRefs(deleteExpired));
NS_ENSURE_SUCCESS(rv, rv);
// Read the first row.
PRBool hasResult;
rv = select->ExecuteStep(&hasResult);
NS_ENSURE_SUCCESS(rv, rv);
if (hasResult) {
nsCString name1, host1, path1;
PRInt64 id1 = select->AsInt64(0);
select->GetUTF8String(1, name1);
select->GetUTF8String(2, host1);
select->GetUTF8String(3, path1);
nsCString name2, host2, path2;
while (1) {
// Read the second row.
rv = select->ExecuteStep(&hasResult);
NS_ENSURE_SUCCESS(rv, rv);
if (!hasResult)
break;
PRInt64 id2 = select->AsInt64(0);
select->GetUTF8String(1, name2);
select->GetUTF8String(2, host2);
select->GetUTF8String(3, path2);
// If the two rows match in (name, host, path), we know the earlier
// row has an earlier expiry time. Delete it.
if (name1 == name2 && host1 == host2 && path1 == path2) {
mozStorageStatementScoper scoper(deleteExpired);
rv = deleteExpired->BindInt64ByName(NS_LITERAL_CSTRING("id"), id1);
NS_ASSERT_SUCCESS(rv);
rv = deleteExpired->ExecuteStep(&hasResult);
NS_ENSURE_SUCCESS(rv, rv);
}
// Make the second row the first for the next iteration.
name1 = name2;
host1 = host2;
path1 = path2;
id1 = id2;
}
}
// Add the creationTime column to the table.
rv = mDBState->dbConn->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
"ALTER TABLE moz_cookies ADD creationTime INTEGER"));
NS_ENSURE_SUCCESS(rv, rv);
// Read in the rowids from the database...
nsCOMPtr<mozIStorageStatement> select;
rv = mDBState->dbConn->CreateStatement(NS_LITERAL_CSTRING(
"SELECT id FROM moz_cookies"), getter_AddRefs(select));
// Copy the id of each row into the new creationTime column.
rv = mDBState->dbConn->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
"UPDATE moz_cookies SET creationTime = "
"(SELECT id WHERE id = moz_cookies.id)"));
NS_ENSURE_SUCCESS(rv, rv);
// ... and use them to generate the creationTime.
nsCOMPtr<mozIStorageStatement> update;
rv = mDBState->dbConn->CreateStatement(NS_LITERAL_CSTRING(
"UPDATE moz_cookies SET creationTime = :id WHERE id = :id"),
getter_AddRefs(update));
NS_ENSURE_SUCCESS(rv, rv);
PRBool hasResult;
while (1) {
rv = select->ExecuteStep(&hasResult);
NS_ENSURE_SUCCESS(rv, rv);
if (!hasResult)
break;
mozStorageStatementScoper scoper(update);
PRInt64 id = select->AsInt64(0);
rv = update->BindInt64ByName(NS_LITERAL_CSTRING("id"), id);
NS_ASSERT_SUCCESS(rv);
rv = update->ExecuteStep(&hasResult);
NS_ENSURE_SUCCESS(rv, rv);
}
// Create a unique index on (name, host, path) to allow fast lookup.
rv = mDBState->dbConn->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
"CREATE UNIQUE INDEX moz_uniqueid "