Maintaining the storage layer/drivers in two languages is burdensome. Since the integration tests require the Perl storage layer/drivers we'll need them even after the core code is migrated to C. Create an interface layer so the Perl code can be removed and new storage drivers/features introduced without adding Perl equivalents.
The goal is to move the integration tests to C so this interface will eventually be removed. That being the case, the interface was designed for maximum compatibility to ease the transition. The result looks a bit hacky but we'll improve it as needed until it can be retired.
This new implementation should behave exactly like the old Perl code with the exception of a few updated log messages.
Remove as much of the Perl code as possible without breaking other commands.
This command was previously forked off from the archive-get command which required a bit of artificial option and log manipulation.
A separate command is easier to test and will work on platforms that don't have fork(), e.g. Windows.
The info messages were spread around and logged differently based on the execution path and in some cases logged nothing at all.
Temporarily track the async server status with a flag so that info messages are not output in the async process. The async process will be refactored as a separate command to be exec'd in a future commit.
A return code of 1 from the archive-get was being logged as an error message at info level but otherwise worked correctly.
Also improve info messages when an archive segment is or is not found.
After a stanza-upgrade it should still be possible to restore backups from the previous version and perform recovery with archive-get. However, archive-get only checked the most recent db version/id and failed.
Also clean up some issues when the same db version/id appears multiple times in the history.
Fixed by Cynthia Shang.
Reported by Clinton Adams.
