Add a P4Info API to the control-plane folder and P4Tools. #4381
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| P4InfoMaps(const P4InfoMaps &) = default; | ||
| P4InfoMaps(P4InfoMaps &&) = default; | ||
| P4InfoMaps &operator=(const P4InfoMaps &) = default; | ||
| P4InfoMaps &operator=(P4InfoMaps &&) = default; |
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Nit: lines 50-53 are automatically generated by the compiler, right? So at least at Google, we tend to omit them.
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Can do, this code is also auotgenerated by my development environment.
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| /// Looks up the P4Runtime id for the given control plane name in the pre-computed P4Runtime-ID | ||
| /// map. @returns std::nullopt if the name is not in the map. | ||
| [[nodiscard]] std::optional<uint64_t> lookupP4RuntimeId(cstring controlPlaneName) const; |
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Nit: "lookup" -> "lookUp"?
"lookup" to me is a noun or perhaps adjective, "look up" is the verb.
| // In case things change down the road. | ||
| static_assert(std::is_convertible_v<p4rt_id_t, uint32_t> && | ||
| std::is_same_v<p4rt_id_t, uint32_t>); | ||
| return x >= y ? static_cast<uint64_t>(x) * x + x + y : x + static_cast<uint64_t>(y) * y; |
| uint64_t szudzikPairing(p4rt_id_t x, p4rt_id_t y); | ||
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| /// This object maps P4 control plane names to their P4Runtime IDs and vice versa. | ||
| /// It uses the P4Info object to populate the maps. |
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It seems like we're additionally introducing new unique IDs for certain objects that do not have unique IDs in P4Runtime / the P4info? Can we document that?
control-plane/p4infoApi.h
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| namespace P4::ControlPlaneAPI { | ||
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| /// Generic meta function which searches an object by @name in the given range | ||
| /// and @returns the P4Runtime representation, or std::nullopt if none is found. |
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Seems to return a null pointer, not std::nullopt. Update documetnation?
Ditto one more time for the other overload
test/gtest/p4runtime.cpp
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| ASSERT_TRUE(myDirectCounter1 != nullptr); | ||
| EXPECT_EQ(unsigned(P4Ids::DIRECT_COUNTER), myDirectCounter1->preamble().id() >> 24); | ||
| EXPECT_EQ(myDirectCounter1->preamble().id(), myTable1->direct_resource_ids(0)); | ||
| } | ||
| // checks that myDirectCounter2 with the right ID prefix | ||
| { | ||
| auto *myTable2 = findTable(*test, "myTable2"); | ||
| auto myTable2 = findP4RuntimeTable(*test->p4Info, "myTable2"); |
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Nit: Here and always, would recommend auto* over auto for pointers, as before.
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This PR adds an API to look up P4Runtime objects in the P4Info file. Unlike the
P4RuntimeSymbolTable, which needs to be explicitly initialized, this API only requires the corresponding P4Info file to look up objects. Additionally, it is possible to look up an object using its ID. This API was partially moved out of thep4runtime.cppgtest. It seemed generally useful. The API is also tested using this file.P4RuntimeMapsis a simple class to cache these pairings of ID and control-plane name. It is constructed from the provided P4Runtime file. For elements such as parameters or matches, which may depend on a parent table, we compute a unique combination of the parameter id and the table parent id using a pairing function (http://szudzik.com/ElegantPairing.pdf).