From b3c1bb1762fceefe9520ae0e442fdd2cce0fca31 Mon Sep 17 00:00:00 2001
From: Gaetan Lepage <gaetan@glepage.com>
Date: Sun, 8 Sep 2024 11:58:54 +0200
Subject: [PATCH] protobufc: fix compatibility with new protobuf

---
 .../libraries/protobufc/default.nix           |  6 ++
 .../protobufc/recent_protobuf_compat.patch    | 80 +++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100644 pkgs/development/libraries/protobufc/recent_protobuf_compat.patch

diff --git a/pkgs/development/libraries/protobufc/default.nix b/pkgs/development/libraries/protobufc/default.nix
index 5a3972527550..73c2d7fba157 100644
--- a/pkgs/development/libraries/protobufc/default.nix
+++ b/pkgs/development/libraries/protobufc/default.nix
@@ -19,6 +19,12 @@ stdenv.mkDerivation rec {
     hash = "sha256-Dkpcc7ZfvAIVY91trRiHuiRFcUGUbQxbheYKTBcq80I=";
   };
 
+  patches = [
+    # https://github.com/protobuf-c/protobuf-c/issues/709
+    # https://github.com/protobuf-c/protobuf-c/pull/711
+    ./recent_protobuf_compat.patch
+  ];
+
   outputs = [ "out" "dev" "lib" ];
 
   nativeBuildInputs = [ autoreconfHook pkg-config ];
diff --git a/pkgs/development/libraries/protobufc/recent_protobuf_compat.patch b/pkgs/development/libraries/protobufc/recent_protobuf_compat.patch
new file mode 100644
index 000000000000..c2d340e1a7f6
--- /dev/null
+++ b/pkgs/development/libraries/protobufc/recent_protobuf_compat.patch
@@ -0,0 +1,80 @@
+diff --git a/protoc-c/c_file.cc b/protoc-c/c_file.cc
+index ca0ad34..c6d8a24 100644
+--- a/protoc-c/c_file.cc
++++ b/protoc-c/c_file.cc
+@@ -117,14 +117,7 @@ FileGenerator::~FileGenerator() {}
+ void FileGenerator::GenerateHeader(io::Printer* printer) {
+   std::string filename_identifier = FilenameIdentifier(file_->name());
+ 
+-  int min_header_version = 1000000;
+-#if GOOGLE_PROTOBUF_VERSION >= 4023000
+-  if (FileDescriptorLegacy(file_).syntax() == FileDescriptorLegacy::SYNTAX_PROTO3) {
+-#else
+-  if (file_->syntax() == FileDescriptor::SYNTAX_PROTO3) {
+-#endif
+-    min_header_version = 1003000;
+-  }
++  const int min_header_version = 1003000;
+ 
+   // Generate top of header.
+   printer->Print(
+diff --git a/protoc-c/c_generator.h b/protoc-c/c_generator.h
+index b8b44aa..4aeb579 100644
+--- a/protoc-c/c_generator.h
++++ b/protoc-c/c_generator.h
+@@ -93,6 +93,12 @@ class PROTOC_C_EXPORT CGenerator : public CodeGenerator {
+                 const std::string& parameter,
+                 OutputDirectory* output_directory,
+                 std::string* error) const;
++
++#if GOOGLE_PROTOBUF_VERSION >= 5026000
++  uint64_t GetSupportedFeatures() const { return CodeGenerator::FEATURE_SUPPORTS_EDITIONS; }
++  Edition GetMinimumEdition() const { return Edition::EDITION_PROTO2; }
++  Edition GetMaximumEdition() const { return Edition::EDITION_PROTO3; }
++#endif
+ };
+ 
+ }  // namespace c
+diff --git a/protoc-c/c_helpers.h b/protoc-c/c_helpers.h
+index 062d330..be28b60 100644
+--- a/protoc-c/c_helpers.h
++++ b/protoc-c/c_helpers.h
+@@ -70,10 +70,6 @@
+ #include <protobuf-c/protobuf-c.pb.h>
+ #include <google/protobuf/io/printer.h>
+ 
+-#if GOOGLE_PROTOBUF_VERSION >= 4023000
+-# include <google/protobuf/descriptor_legacy.h>
+-#endif
+-
+ namespace google {
+ namespace protobuf {
+ namespace compiler {
+@@ -173,13 +169,21 @@ struct NameIndex
+ int compare_name_indices_by_name(const void*, const void*);
+ 
+ // Return the syntax version of the file containing the field.
+-// This wrapper is needed to be able to compile against protobuf2.
+ inline int FieldSyntax(const FieldDescriptor* field) {
+-#if GOOGLE_PROTOBUF_VERSION >= 4023000
+-  return FileDescriptorLegacy(field->file()).syntax() == FileDescriptorLegacy::SYNTAX_PROTO3 ? 3 : 2;
+-#else
+-  return field->file()->syntax() == FileDescriptor::SYNTAX_PROTO3 ? 3 : 2;
+-#endif
++  auto proto = FileDescriptorProto();
++  field->file()->CopyTo(&proto);
++
++  if (proto.has_syntax()) {
++    auto syntax = proto.syntax();
++    assert(syntax == "proto2" || syntax == "proto3");
++    if (syntax == "proto2") {
++      return 2;
++    } else if (syntax == "proto3") {
++      return 3;
++    }
++  }
++
++  return 2;
+ }
+ 
+ // Work around changes in protobuf >= 22.x without breaking compilation against