All the methods in this module will need to be implemented via the command-line in order to get rid of LibC, so the first step is to reduce the code in the module as much as possible.
First remove storageDb() and use storageTest() instead. Then create storageTest() using pgBackRestTest::Common::Storage which has no dependencies on LibC. Now the only storage using the LibC interface is storageRepo().
Remove all link functions since those operations cannot be performed on a repo unless it is Posix, in which case the LibC interface is not needed. Same for owner().
Remove pathSync() because syncs are not required in the tests. No test data is reused after a crash.
Path create/exists functions should never be explicitly performed on a repo so remove those. File exists can be implemented by calling info() instead.
Remove encryption detection functions which were only used by Backup/Archive::Info reconstruct() which are now obsolete.
Remove all filters except pgBackRest::Storage::Filter::CipherBlock since they are not being used. That also means there are no filters returning results so remove all the result code.
Move hashSize() and pathAbsolute() into pgBackRest::Storage::Base where they can be shared between pgBackRest::Storage::Storage and pgBackRestTest::Common::Storage.
This macro block encapsulates the common pattern of switching to the prior (formerly called old) mem context to return results from a function.
Also rename MEM_CONTEXT_OLD() to memContextPrior(). This violates our convention of macros being in all caps but memContextPrior() will become a function very soon so this will reduce churn.
Remove embedded Perl from the distributed binary. This includes code, configure, Makefile, and packages. The distributed binary is now pure C.
Remove storagePathEnforceSet() from the C Storage object which allowed Perl to write outside of the storage base directory. Update mock/all and real/all integration tests to use storageLocal() where they were violating this rule.
Remove "c" option that allowed the remote to tell if it was being called from C or Perl.
Code to convert options to JSON for passing to Perl (perl/config.c) has been moved to LibC since it is still required for Perl integration tests.
Update build and installation instructions in the user guide.
Remove all Perl unit tests.
Remove obsolete Perl code. In particular this included all the Perl protocol code which required modifications to the Perl storage, manifest, and db objects that are still required for integration testing but only run locally. Any remaining Perl code is required for testing, documentation, or code generation.
Rename perlReq to binReq in define.yaml to indicate that the binary is required for a test. This had been the actual meaning for quite some time but the key was never renamed.
Adding a dummy column which is always set by the P() macro allows a single macro to be used for parameters or no parameters without violating C's prohibition on the {} initializer.
-Wmissing-field-initializers remains disabled because it still gives wildly different results between versions of gcc.
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.
Remove "File" and "Driver" from object names so they are shorter and easier to keep consistent.
Also remove the "driver" directory so storage implementations are visible directly under "storage".
The function pointer casting used when creating drivers made changing interfaces difficult and led to slightly divergent driver implementations. Unit testing caught production-level errors but there were a lot of small issues and the process was harder than it should have been.
Use void pointers instead so that no casts are required. Introduce the THIS_VOID and THIS() macros to make dealing with void pointers a little safer.
Since we don't want to expose void pointers in header files, driver functions have been removed from the headers and the various driver objects return their interface type. This cuts down on accessor methods and the vast majority of those functions were not being used. Move functions that are still required to .intern.h.
Remove the special "C" crypto functions that were used in libc and instead use the standard interface.
The external storage interfaces (Storage, StorageFileRead, etc.) have been stable for a while, but internally they were calling the posix driver functions directly.
Create driver interfaces for storage, fileRead, and fileWrite and remove all references to the posix driver outside storage/driver/posix (with the exception of a direct call to pathRemove() in Perl LibC).
Posix is still the only available driver so more adjustment may be needed, but this should represent the bulk of the changes.
This implementation should be faster because it does not stat each file. It simply assumes that most directory entries are files so attempts an unlink() first. If the entry is reported by error codes to be a directory then it attempts an rmdir().
David Steele
Cynthia Shang
David Steele