tree 5d5599aa22853546f54df045f0461c55c7c09423
parent 4247b1bc26f6c52d5abf86368d8aac2e0a2bcffb
author Chressie Himpel <chressie@golang.org> 1737111979 +0100
committer Michael Stapelberg <stapelberg@google.com> 1742471017 -0700

internal_gengo: generate a const string literal for the raw descriptor

Putting the raw descriptor into a const string literal has been
attempted before (go.dev/cl/638135), but that change has been reverted
(go.dev/cl/642857) because the generated string contained non-UTF-8
bytes.

This time we let the %q formatting verb handle the conversion of the
bytes into a UTF-8-conform string literal.

We also found an interesting way to split the bytes into multiple
"lines": We use the fact that FileDescriptorProto (and some
submessages) have a LEN encoded field (string) with field_number=1,
so splitting at 0x0a (incidentally a newline character in ascii)
we get a splitting that almost looks readable.

As expected, the const string literals are landing in .rodata.

    % (go test -c google.golang.org/protobuf/internal/reflection_test &&
       strings -tx reflection_test.test | grep -F '2&.goproto.proto.testeditions.ImportEnumB' &&
       readelf -SW reflection_test.test | grep -F .rodata)
     321b07 2&.goproto.proto.testeditions.ImportEnumB
       [ 2] .rodata           PROGBITS        000000000065a000 25a000 131fc1 00   A  0   0 32

Change-Id: I77aef7b5032e52c2c485cf662045c9028549fd94
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/657895
Commit-Queue: Michael Stapelberg <stapelberg@google.com>
Reviewed-by: Cassondra Foesch <cfoesch@gmail.com>
Reviewed-by: Nicolas Hillegeer <aktau@google.com>
Reviewed-by: Michael Stapelberg <stapelberg@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>