Prior to this change:
parse(buf, len) -> len + N
...would indicate that the next N bytes of the input are not
needed, *and* would advance the decoding position by this
much.
After this change:
parse(buf, len) -> len + N
parse(NULL, N) -> N
...can be used to achieve the same thing. But skipping the
N bytes is not explicitly performed by the user. A user that
doesn't want/need to skip can just say:
parsed = parse(buf, len);
if (parsed < len) {
// Handle suspend, advance stream by "parsed".
} else {
// Stream was advanced by "len" (even if parsed > len).
}
Updated unit tests to test this new behavior, and refactored
test utility code a bit to support it.
A large part of this change contains surface-level
porting, like moving variable declarations to the
top of the block.
However there are a few more substantial things too:
- moved internal-only struct definitions to a separate
file (structdefs.int.h), for greater encapsulation
and ABI compatibility.
- removed the UPB_UPCAST macro, since it requires access
to the internal-only struct definitions. Replaced uses
with calls to inline, type-safe casting functions.
- removed the UPB_DEFINE_CLASS/UPB_DEFINE_STRUCT macros.
Class and struct definitions are now more explicit -- you
get to see the actual class/struct keywords in the source.
The casting convenience functions have been moved into
UPB_DECLARE_DERIVED_TYPE() and UPB_DECLARE_DERIVED_TYPE2().
- the new way that we duplicate base methods in derived types
is also more convenient and requires less duplication.
It is also less greppable, but hopefully that is not
too big a problem.
Compiler flags (-std=c89 -pedantic) should help to rigorously
enforce that the code is free of C99-isms.
A few functions are not available in C89 (strtoll). There
are temporary, hacky solutions in place.
- rewritten decoder; interpreted decoder is bytecode-based,
JIT decoder no longer falls back to the interpreter.
- C++ improvements: C++11-compatible iterators, upb::reffed_ptr
for RAII refcounting, better upcast/downcast support.
- removed the gross upb_value abstraction from public upb.h.
- Better error reporting for upb::Def setters.
- error reporting for upb::Handlers setters.
- made the start/endmsg handlers a little less special-cased.
Major changes:
- Got rid of all bytestream interfaces in favor of
using regular handlers.
- new Pipeline object represents a upb pipeline, does
bump allocation internally to manage memory.
- proto2 support now can handle extensions.
Many things have changed and been simplified.
The memory-management story for upb_def and upb_handlers
is much more robust; upb_def and upb_handlers should be
fairly stable interfaces now. There is still much work
to do for the runtime component (upb_sink).
Josh Haberman
Josh Haberman