From e55670d0d0dfbc1c6844bba90605a025649a7188 Mon Sep 17 00:00:00 2001
From: Mohammad Nejati <ashtumashtum@gmail.com>
Date: Tue, 26 Nov 2024 06:48:05 +0000
Subject: [PATCH] Remove Boost.Scope dependency from examples

---
 CMakeLists.txt                                | 46 +++++++++----------
 .../server-flex-awaitable/CMakeLists.txt      |  2 +-
 .../advanced/server-flex-awaitable/Jamfile    |  1 -
 .../advanced_server_flex_awaitable.cpp        | 40 ++++++++++++----
 4 files changed, 56 insertions(+), 33 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 850f4689..fd432df3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -55,28 +55,28 @@ set(BOOST_SRC_DIR ${DEFAULT_BOOST_SRC_DIR} CACHE STRING "Boost source dir to use
 #-------------------------------------------------
 # The boost super-project requires one explicit dependency per-line.
 set(BOOST_BEAST_DEPENDENCIES
-        Boost::asio
-        Boost::assert
-        Boost::bind
-        Boost::config
-        Boost::container
-        Boost::container_hash
-        Boost::core
-        Boost::endian
-        Boost::intrusive
-        Boost::logic
-        Boost::mp11
-        Boost::optional
-        Boost::preprocessor
-        Boost::smart_ptr
-        Boost::static_assert
-        Boost::static_string
-        Boost::system
-        Boost::throw_exception
-        Boost::type_index
-        Boost::type_traits
-        Boost::winapi
-        )
+    Boost::asio
+    Boost::assert
+    Boost::bind
+    Boost::config
+    Boost::container
+    Boost::container_hash
+    Boost::core
+    Boost::endian
+    Boost::intrusive
+    Boost::logic
+    Boost::mp11
+    Boost::optional
+    Boost::preprocessor
+    Boost::smart_ptr
+    Boost::static_assert
+    Boost::static_string
+    Boost::system
+    Boost::throw_exception
+    Boost::type_index
+    Boost::type_traits
+    Boost::winapi)
+
 foreach (BOOST_BEAST_DEPENDENCY ${BOOST_BEAST_DEPENDENCIES})
     if (BOOST_BEAST_DEPENDENCY MATCHES "^[ ]*Boost::([A-Za-z0-9_]+)[ ]*$")
         list(APPEND BOOST_BEAST_INCLUDE_LIBRARIES ${CMAKE_MATCH_1})
@@ -87,7 +87,7 @@ if (BOOST_BEAST_BUILD_TESTS)
     set(BOOST_BEAST_UNIT_TEST_LIBRARIES filesystem)
 endif ()
 if (BOOST_BEAST_BUILD_EXAMPLES)
-    set(BOOST_BEAST_EXAMPLE_LIBRARIES scope json)
+    set(BOOST_BEAST_EXAMPLE_LIBRARIES json)
 endif ()
 # Complete dependency list
 set(BOOST_INCLUDE_LIBRARIES ${BOOST_BEAST_INCLUDE_LIBRARIES} ${BOOST_BEAST_UNIT_TEST_LIBRARIES} ${BOOST_BEAST_EXAMPLE_LIBRARIES})
diff --git a/example/advanced/server-flex-awaitable/CMakeLists.txt b/example/advanced/server-flex-awaitable/CMakeLists.txt
index 0090f601..3e557b1a 100644
--- a/example/advanced/server-flex-awaitable/CMakeLists.txt
+++ b/example/advanced/server-flex-awaitable/CMakeLists.txt
@@ -20,7 +20,7 @@ target_include_directories(advanced-server-flex-awaitable
     PRIVATE ${PROJECT_SOURCE_DIR})
 
 target_link_libraries(advanced-server-flex-awaitable
-    PRIVATE Boost::beast Boost::scope OpenSSL::SSL OpenSSL::Crypto)
+    PRIVATE Boost::beast OpenSSL::SSL OpenSSL::Crypto)
 
 set_target_properties(advanced-server-flex-awaitable
     PROPERTIES FOLDER "example-advanced-server")
diff --git a/example/advanced/server-flex-awaitable/Jamfile b/example/advanced/server-flex-awaitable/Jamfile
index 8b090c54..bf60ef0e 100644
--- a/example/advanced/server-flex-awaitable/Jamfile
+++ b/example/advanced/server-flex-awaitable/Jamfile
@@ -12,7 +12,6 @@ import ac ;
 project
     : requirements
         [ ac.check-library /boost/beast/test//lib-asio-ssl : <library>/boost/beast/test//lib-asio-ssl/<link>static : <build>no ]
-        <library>/boost/scope//boost_scope
     ;
 
 exe advanced-server-flex-awaitable :
diff --git a/example/advanced/server-flex-awaitable/advanced_server_flex_awaitable.cpp b/example/advanced/server-flex-awaitable/advanced_server_flex_awaitable.cpp
index f5da650b..0c62719d 100644
--- a/example/advanced/server-flex-awaitable/advanced_server_flex_awaitable.cpp
+++ b/example/advanced/server-flex-awaitable/advanced_server_flex_awaitable.cpp
@@ -20,7 +20,6 @@
 #include <boost/asio/ssl.hpp>
 #include <boost/beast.hpp>
 #include <boost/beast/ssl.hpp>
-#include <boost/scope/scope_exit.hpp>
 
 #include <algorithm>
 #include <cstdlib>
@@ -243,17 +242,42 @@ public:
         auto lg = std::lock_guard{ mtx_ };
         auto cs = css_.emplace(css_.end());
 
+        class remover
+        {
+            task_group* tg_;
+            decltype(css_)::iterator cs_;
+
+        public:
+            remover(
+                task_group* tg,
+                decltype(css_)::iterator cs)
+                : tg_{ tg }
+                , cs_{ cs }
+            {
+            }
+
+            remover(remover&& other) noexcept
+                : tg_{ std::exchange(other.tg_, nullptr) }
+                , cs_{ other.cs_ }
+            {
+            }
+
+            ~remover()
+            {
+                if(tg_)
+                {
+                    auto lg = std::lock_guard{ tg_->mtx_ };
+                    if(tg_->css_.erase(cs_) == tg_->css_.end())
+                        tg_->cv_.cancel();
+                }
+            }
+        };
+
         return net::bind_cancellation_slot(
             cs->slot(),
             net::consign(
                 std::forward<CompletionToken>(completion_token),
-                boost::scope::make_scope_exit(
-                    [this, cs]()
-                    {
-                        auto lg = std::lock_guard{ mtx_ };
-                        if(css_.erase(cs) == css_.end())
-                            cv_.cancel();
-                    })));
+                remover{ this, cs }));
     }
 
     /** Emits the signal to all child tasks and invokes the slot's