This will move us towards keeping all these encapsulation breaks in a common place.
This also removes the IFTTT blocks. Keeping IFTTT blocks for each language would become unmanageable, but going forward we will know to look in `//third_party/upb/bits` whenever the internal data structures in upb change.
PiperOrigin-RevId: 547494495
upb has an implementation-specific maximum of 63 required fields per message. We need to verify this limit when building a MiniTable.
PiperOrigin-RevId: 546929196
This special `proto_library` behavior is known as an *alias library*:
https://bazel.build/reference/be/protocol-buffer#proto_library_args
Without this CL, the compilation of the added test fails with:
```
test_import_empty_srcs.upb.c:12:10: error:
module :test_import_empty_srcs_proto.upb does not depend on a
module exporting 'test.upb.h'
```
PiperOrigin-RevId: 545153380
After this change, `mini_table` only has MiniTable definitions themselves. Everything having to do with the MiniDescriptor wire format is in `mini_descriptor`.
Also rearranged some of the files in mini_table to have better structure for `internal/`.
This CL contains no functional change.
PiperOrigin-RevId: 543529112
Move to a friend nonmember functions taking both arguments by reference-to-const.
Closes#1199
COPYBARA_INTEGRATE_REVIEW=https://github.com/protocolbuffers/upb/pull/1199 from phallot:fix/ambiguous-reversed-operator 4ef9f65e7539df330943a55e257b5f8a87a208ca
PiperOrigin-RevId: 542572888
- Match build target names to their corresponding file names (remove stuttering)
- Replace a dep on (deprecated) :upb with a dep on :wire
- Mark :struct_upb_proto as testonly
- Group the cc_test targets together
PiperOrigin-RevId: 541408625
`upb_MiniTableField_CType()` was directly checking the `descriptortype` in `upb_MiniTableField`, without taking `field->mode` into account -- which can indicate that an int32 is actually an enum, or that bytes is really a string.
PiperOrigin-RevId: 537975302
The `kUpb_DecodeOption_ExperimentalAllowUnlinked` flag to the decoder will enable the new behavior. When that flag is not passed, tree shaking with the old model will still be possible.
"Dynamic tree shaking" in upb is a feature that allows messages to be parsed even if the MiniTables have not been fully linked. Unlinked sub-message fields can be parsed by preserving their data in the unknown fields. If the application later discovers that the message field is actually needed, the MiniTable can be patched to properly link that field, and existing message instances can "promote" the data from the unknown fields to an actual message of the correct type.
Before this change, dynamic tree shaking stored unparsed message data in the unknown fields of the *parent*. In effect, we were treating the field as if it did not exist at all. This meant that parsing an unlinked field did not affect the hasbits or oneof cases of the parent, nor did it create a `upb_Array` or `upb_Map` for array/map fields. Only when a message was linked and promoted did any of these things occur.
While this model had some amount of conceptual simplicity, it caused significant problems with oneofs. When multiple fields inside a single oneof are parsed from the wire, order matters, because later oneof fields must overwrite earlier ones. Dynamic tree shaking can mean that some fields in a oneof are linked while others are not. It is essential that we preserve this ordering semantic even when dynamic tree shaking is being used, but it is difficult to do if the oneof's data can be split between linked fields (which have been reified into parsed field data) and unlinked fields (whose data lives in the unknown fields of the parent).
To solve this problem, this CL changes the representation for unlinked fields. Instead of being placed in the parent's unknown fields, we create an actual message instance for each unlinked message we parse, but we use a placeholder "empty message" MiniTable as the message's type. All of the message's data will therefore be placed into the "empty message's" unknown fields. But unlike before, this "empty message" is actually present according to the hasbits, oneof case, and `upb_Array`/`upb_Map` of the parent. This means that all of the oneof presence logic works as normal.
Since the MiniTable can be patched at any time, we need a bit in the message instance itself to signal whether a pointer to a sub-message is an "empty message" or not. When dynamic tree shaking is in use, all users must be capable of recognizing an empty message and acting accordingly (promoting, etc) even if the MiniTable itself says that the field is linked.
Because dynamic tree shaking imposes this extra requirement on users, we require that users pass an extra option to the decoder to allow parsing of unlinked sub-messages. Many existing users of upb (Ruby, PHP, Python, etc) will always have fully-linked MiniTables, so there is no reason for them to add extra logic to handle empty messages. By omitting the `kUpb_DecodeOption_ExperimentalAllowUnlinked` option, they will be relieved of the duty to check the tagged pointer that would indicate an empty, unlinked message.
For existing users of dynamic tree shaking, there are three main changes:
1. The APIs in message/promote.h have changed, and users will need to update to the new interfaces.
2. The model for maps has changed slightly. Before, we required that map entries always had their values linked; for dynamic tree shaking to apply to maps, we required that the *entry* was left unlinked, not the entry's value. In the new model, that is reversed: map entries must always be linked, but a map entry's value can be unlinked.
3. The presence model for unlinked fields has changed. Unlinked fields will now register as "present" from the perspective of hasbits, oneof cases, and array/map entries. Users must test the tagged pointer to know if a message is of the correct, linked type or whether it is a placeholder "empty" message. There is a new function `upb_Message_GetTaggedMessagePtr()`, as well as a new accessor `upb_MessageValue.tagged_msg_val` that can be used to read and test the tagged pointer directly.
PiperOrigin-RevId: 535288031
Fixes: https://github.com/protocolbuffers/protobuf/issues/12580
When `upb_Map_Delete(map, k, &v)` was called for a string-keyed map, the returned value `v` contained garbage data instead of the true string length.
Since `map.delete(k)` in Ruby returns the deleted value, this was causing a garbage length to be used when allocating and copying data.
PiperOrigin-RevId: 535261609
Prior to this change, all sub-messages and sub-enums were initialized to NULL. Going forward, sub-messages will need to be initialized differently than sub-enums.
To facilitate this, we change the order of subs, so that sub-messages always come before sub-enums. Then when we allocate the subs, we can initialize them in two separate loops.
This unfortunately requires one extra iteration over the fields if any closed enums are present, to adjust the `submsg_index` according to how many sub-messages were seen.
This CL is the first step towards changing how we handle unlinked sub-messages.
PiperOrigin-RevId: 529100966
C++20 requires that types used in std::vector are complete. Group's constructor definition requires that UnknownFields' destructor be available, which means UnknownField must be complete.
PiperOrigin-RevId: 527341365
Since promotion is a more complicated operation than the simple accessors, and since promotion logic will likely be changing before long, it helps to put promotion-related logic in a separate place and rule.
PiperOrigin-RevId: 525519707
- Fixed a couple of broken tests that were probably invoking UB.
- Excluded python/... and js/..., as these do not work with Windows.
PiperOrigin-RevId: 525228589
The fields of upb_MiniTableField are intended to be internal-only, accessed only through public functions like `upb_MiniTable_GetSubMessageTable()`. But over time, clients have started accessing many of these fields directly. This is an easy mistake to make, as there is no clear signal that the fields should not be used in applications. This makes the implementation difficult to change without breaking users.
The new `UPB_PRIVATE()` macro appends an unpredictable string to each private symbol. This makes it very difficult to accidentally use a private symbol, since users would need to write something like `field->submsg_index_dont_copy_me__upb_internal_use_only`. This is still possible to do, but it leaves a clear wart in the code showing that an an encapsulation break has occurred. The `UPB_PRIVATE()` macro itself is defined in `port/def.inc`, which users cannot include directly.
Once we land this, more such CLs will follow for the other fields of `upb_MiniTable*`. We will add inline functions as needed to provide the semantic functionality needed by users.
PiperOrigin-RevId: 523166901
An earlier change inadvertently disabled several GitHub Actions due to a syntax error.
This broke the CI for upb because several expected tests were never running.
I was not able to get the Windows CI test fully working, so I disabled it for now.
PiperOrigin-RevId: 522652505
Joshua Haberman
Jason Lunn
Protobuf Team Bot
Eric Salo
Pierre Hallot
Jie Luo
Matt Kulukundis
Deanna Garcia
Mike Kruskal