[C++ BUILD] Internal changes for base context propagation.

PiperOrigin-RevId: 663460841

BUILD

@@ -907,6 +907,7 @@ grpc_cc_library(
     ],
     visibility = ["@grpc:grpc++_public_hdrs"],
     deps = [
+        "global_callback_hook",
         "grpc_public_hdrs",
         "//src/core:gpr_atm",
     ],
@@ -951,6 +952,7 @@ grpc_cc_library(
     tags = ["nofixdeps"],
     visibility = ["@grpc:public"],
     deps = [
+        "global_callback_hook",
         "grpc++_base",
         "//src/core:gpr_atm",
         "//src/core:slice",
@@ -1260,6 +1262,7 @@ grpc_cc_library(
     deps = [
         "channel_arg_names",
         "generic_stub_internal",
+        "global_callback_hook",
         "gpr",
         "grpc++_base_unsecure",
         "grpc++_codegen_proto",
@@ -2455,6 +2458,7 @@ grpc_cc_library(
         "config",
         "exec_ctx",
         "generic_stub_internal",
+        "global_callback_hook",
         "gpr",
         "grpc",
         "grpc++_codegen_proto",
@@ -2544,6 +2548,7 @@ grpc_cc_library(
         "config",
         "exec_ctx",
         "generic_stub_internal",
+        "global_callback_hook",
         "gpr",
         "grpc_base",
         "grpc_core_credentials_header",
@@ -4913,6 +4918,22 @@ grpc_cc_library(
     ],
 )
 
+grpc_cc_library(
+    name = "global_callback_hook",
+    srcs = [
+        "src/cpp/client/global_callback_hook.cc",
+    ],
+    hdrs = [
+        "include/grpcpp/support/global_callback_hook.h",
+    ],
+    external_deps = [
+        "absl/base:no_destructor",
+        "absl/log:check",
+        "absl/functional:function_ref",
+    ],
+    language = "c++",
+)
+
 # TODO(yashykt): Remove the UPB definitions from here once they are no longer needed
 ### UPB Targets
 

include/grpcpp/support/callback_common.h

@@ -30,6 +30,7 @@
 #include <grpcpp/impl/codegen/channel_interface.h>
 #include <grpcpp/impl/completion_queue_tag.h>
 #include <grpcpp/support/config.h>
+#include <grpcpp/support/global_callback_hook.h>
 #include <grpcpp/support/status.h>
 
 namespace grpc {
@@ -127,7 +128,18 @@ class CallbackWithStatusTag : public grpc_completion_queue_functor {
     auto status = std::move(status_);
     func_ = nullptr;     // reset to clear this out for sure
     status_ = Status();  // reset to clear this out for sure
-    CatchingCallback(std::move(func), std::move(status));
+    GetGlobalCallbackHook()->RunCallback(
+        call_, [func = std::move(func), status = std::move(status)]() {
+#if GRPC_ALLOW_EXCEPTIONS
+          try {
+            func(status);
+          } catch (...) {
+            // nothing to return or change here, just don't crash the library
+          }
+#else   // GRPC_ALLOW_EXCEPTIONS
+  func(status);
+#endif  // GRPC_ALLOW_EXCEPTIONS
+        });
     grpc_call_unref(call_);
   }
 };
@@ -214,7 +226,17 @@ class CallbackWithSuccessTag : public grpc_completion_queue_functor {
 #endif
 
     if (do_callback) {
-      CatchingCallback(func_, ok);
+      GetGlobalCallbackHook()->RunCallback(call_, [this, ok]() {
+#if GRPC_ALLOW_EXCEPTIONS
+        try {
+          func_(ok);
+        } catch (...) {
+          // nothing to return or change here, just don't crash the library
+        }
+#else   // GRPC_ALLOW_EXCEPTIONS
+  func_(ok);
+#endif  // GRPC_ALLOW_EXCEPTIONS
+      });
     }
   }
 };

include/grpcpp/support/global_callback_hook.h

@@ -0,0 +1,58 @@
+// Copyright 2024 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GRPCPP_SUPPORT_GLOBAL_CALLBACK_HOOK_H
+#define GRPCPP_SUPPORT_GLOBAL_CALLBACK_HOOK_H
+
+#include "absl/functional/function_ref.h"
+
+struct grpc_call;
+
+namespace grpc {
+
+class GlobalCallbackHook {
+ public:
+  virtual ~GlobalCallbackHook() = default;
+  virtual void RunCallback(grpc_call* call,
+                           absl::FunctionRef<void()> callback) = 0;
+
+ protected:
+  // An exception-safe way of invoking a user-specified callback function.
+  template <class Func, class... Args>
+  void CatchingCallback(Func&& func, Args&&... args) {
+#if GRPC_ALLOW_EXCEPTIONS
+    try {
+      func(std::forward<Args>(args)...);
+    } catch (...) {
+      // nothing to return or change here, just don't crash the library
+    }
+#else   // GRPC_ALLOW_EXCEPTIONS
+    func(std::forward<Args>(args)...);
+#endif  // GRPC_ALLOW_EXCEPTIONS
+  }
+};
+
+class DefaultGlobalCallbackHook final : public GlobalCallbackHook {
+ public:
+  void RunCallback(grpc_call* call,
+                   absl::FunctionRef<void()> callback) override {
+    CatchingCallback(callback);
+  }
+};
+
+std::shared_ptr<GlobalCallbackHook> GetGlobalCallbackHook();
+void SetGlobalCallbackHook(GlobalCallbackHook* hook);
+}  // namespace grpc
+
+#endif  // GRPCPP_SUPPORT_GLOBAL_CALLBACK_HOOK_H