From: Casey Bodley <cbodley@redhat.com>
Date: Wed, 26 Mar 2025 21:57:55 +0000 (-0400)
Subject: librados/asio: add async_watch/unwatch()
X-Git-Tag: testing/wip-vshankar-testing-20250411.090237-debug~22^2~4
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=27168f00aa55157a917e89d0ddddb2a09b05eff8;p=ceph-ci.git

librados/asio: add async_watch/unwatch()

Signed-off-by: Casey Bodley <cbodley@redhat.com>
---

diff --git a/src/librados/librados_asio.h b/src/librados/librados_asio.h
index 00a82f28517..26e4fe2fa2c 100644
--- a/src/librados/librados_asio.h
+++ b/src/librados/librados_asio.h
@@ -268,6 +268,65 @@ auto async_operate(IoExecutor ex, IoCtx& io, const std::string& oid,
       }, token, ex, io, oid, std::move(write_op), flags, trace_ctx);
 }
 
+/// Calls IoCtx::aio_watch2() and arranges for the AioCompletion to call a
+/// given handler with signature (error_code, version_t).
+///
+/// The given IoCtx reference is not required to remain valid, but some IoCtx
+/// instance must preserve its underlying implementation until completion.
+template <boost::asio::execution::executor IoExecutor, typename CompletionToken>
+auto async_watch(IoExecutor ex, IoCtx& io, const std::string& oid,
+                 uint64_t* handle, librados::WatchCtx2* ctx,
+                 uint32_t timeout_ms, CompletionToken &&token)
+{
+  using Op = detail::AsyncOp<void>;
+  using Signature = typename Op::Signature;
+  return boost::asio::async_initiate<CompletionToken, Signature>(
+      [] (auto handler, IoExecutor ex, const IoCtx& i, const std::string& oid,
+          uint64_t* handle, librados::WatchCtx2* ctx, uint32_t timeout_ms) {
+        constexpr bool is_read = false;
+        auto p = Op::create(ex, is_read, std::move(handler));
+        auto& op = p->user_data;
+
+        IoCtx& io = const_cast<IoCtx&>(i);
+        int ret = io.aio_watch2(oid, op.aio_completion.get(),
+                                handle, ctx, timeout_ms);
+        if (ret < 0) {
+          auto ec = boost::system::error_code{-ret, librados::detail::err_category()};
+          ceph::async::post(std::move(p), ec, 0);
+        } else {
+          p.release(); // release ownership until completion
+        }
+      }, token, ex, io, oid, handle, ctx, timeout_ms);
+}
+
+/// Calls IoCtx::aio_unwatch() and arranges for the AioCompletion to call a
+/// given handler with signature (error_code, version_t).
+///
+/// The given IoCtx reference is not required to remain valid, but some IoCtx
+/// instance must preserve its underlying implementation until completion.
+template <boost::asio::execution::executor IoExecutor, typename CompletionToken>
+auto async_unwatch(IoExecutor ex, IoCtx& io, uint64_t handle,
+                   CompletionToken &&token)
+{
+  using Op = detail::AsyncOp<void>;
+  using Signature = typename Op::Signature;
+  return boost::asio::async_initiate<CompletionToken, Signature>(
+      [] (auto handler, IoExecutor ex, const IoCtx& i, uint64_t handle) {
+        constexpr bool is_read = false;
+        auto p = Op::create(ex, is_read, std::move(handler));
+        auto& op = p->user_data;
+
+        IoCtx& io = const_cast<IoCtx&>(i);
+        int ret = io.aio_unwatch(handle, op.aio_completion.get());
+        if (ret < 0) {
+          auto ec = boost::system::error_code{-ret, librados::detail::err_category()};
+          ceph::async::post(std::move(p), ec, 0);
+        } else {
+          p.release(); // release ownership until completion
+        }
+      }, token, ex, io, handle);
+}
+
 /// Calls IoCtx::aio_notify() and arranges for the AioCompletion to call a
 /// given handler with signature (error_code, version_t, bufferlist).
 ///