[php-src] PR #24375: ext/pdo_odbc: add support for PDO::ATTR_TIMEOUT

Pull Request: https://github.com/php/php-src/pull/24375 Author: NattyNarwhal From the main commit: > ODBC has both a connection timeout for the connection level and a query > timeout at the statement level. Annoyingly, these are somewhat poorly > defined. The connection timeout, for instance, can be defined as either > a login/connection setup timeout, or as a generic "any action" timeout, > and if the latter, the query timeout may not necessarily be implemented. > > Accordingly, because we have no way to differentiate, we have to set > both, and have special handling for the initial connection, as the > setAttribute call won't handle early enough if it only handles initial > connection timeouts. This means changing it after for a connection isn't > relevant for existing statements that have already been constructed; > this commit doesn't add a way to change it for a statement after > changing it on the connection (be it via setAttribute on the statement, > or somehow changing statements from the connection setAttribute). > > Also annoying is the difference in behaviour between drivers when a > timeout happens. For example, SQL Server has a query timeout which just > gracefully ends the current query, but Db2i only has a connection > timeout which puts the whole connection into an invalid state (but at > least it should fail a liveness check for a persistent connection). We > don't have much control over this unfortunately. > > In the future, we should consider clarifying the PDO timeout attribute > behaviour's on statements vs. connections, or make them separate > attributes, like how PDO_DBLIB has. May need some refinement for i.e. statement timeout stuff, but I suspect anything needing a new attribute will need the RFC process.