From 2966efd025add4a0d5bdbd98e203460fadaf1460 Mon Sep 17 00:00:00 2001
From: Valentin Balaschenko <13349202+vlntb@users.noreply.github.com>
Date: Wed, 25 Jun 2025 19:31:27 +0100
Subject: [PATCH] move to std counting semaphore

---
 src/xrpld/core/detail/Workers.cpp |  6 +--
 src/xrpld/core/detail/Workers.h   | 11 ++--
 src/xrpld/core/detail/semaphore.h | 83 -------------------------------
 3 files changed, 8 insertions(+), 92 deletions(-)
 delete mode 100644 src/xrpld/core/detail/semaphore.h

diff --git a/src/xrpld/core/detail/Workers.cpp b/src/xrpld/core/detail/Workers.cpp
index 53b5944ac0..3050673da8 100644
--- a/src/xrpld/core/detail/Workers.cpp
+++ b/src/xrpld/core/detail/Workers.cpp
@@ -104,7 +104,7 @@ Workers::setNumberOfThreads(int numberOfThreads)
             ++m_pauseCount;
 
             // Pausing a thread counts as one "internal task"
-            m_semaphore.notify();
+            m_semaphore.release();
         }
     }
 
@@ -128,7 +128,7 @@ Workers::stop()
 void
 Workers::addTask()
 {
-    m_semaphore.notify();
+    m_semaphore.release();
 }
 
 int
@@ -213,7 +213,7 @@ Workers::Worker::run()
 
             // Acquire a task or "internal task."
             //
-            m_workers.m_semaphore.wait();
+            m_workers.m_semaphore.acquire();
 
             // See if there's a pause request. This
             // counts as an "internal task."
diff --git a/src/xrpld/core/detail/Workers.h b/src/xrpld/core/detail/Workers.h
index 3f41e382b0..294fcc9884 100644
--- a/src/xrpld/core/detail/Workers.h
+++ b/src/xrpld/core/detail/Workers.h
@@ -20,13 +20,12 @@
 #ifndef RIPPLE_CORE_WORKERS_H_INCLUDED
 #define RIPPLE_CORE_WORKERS_H_INCLUDED
 
-#include <xrpld/core/detail/semaphore.h>
-
 #include <xrpl/beast/core/LockFreeStack.h>
 
 #include <atomic>
 #include <condition_variable>
 #include <mutex>
+#include <semaphore>
 #include <string>
 #include <thread>
 
@@ -223,10 +222,10 @@ private:
     std::condition_variable m_cv;  // signaled when all threads paused
     std::mutex m_mut;
     bool m_allPaused;
-    semaphore m_semaphore;           // each pending task is 1 resource
-    int m_numberOfThreads;           // how many we want active now
-    std::atomic<int> m_activeCount;  // to know when all are paused
-    std::atomic<int> m_pauseCount;   // how many threads need to pause now
+    std::counting_semaphore<> m_semaphore;  // each pending task is 1 resource
+    int m_numberOfThreads;                  // how many we want active now
+    std::atomic<int> m_activeCount;         // to know when all are paused
+    std::atomic<int> m_pauseCount;  // how many threads need to pause now
     std::atomic<int>
         m_runningTaskCount;  // how many calls to processTask() active
     beast::LockFreeStack<Worker> m_everyone;  // holds all created workers
diff --git a/src/xrpld/core/detail/semaphore.h b/src/xrpld/core/detail/semaphore.h
deleted file mode 100644
index 3b64265bb1..0000000000
--- a/src/xrpld/core/detail/semaphore.h
+++ /dev/null
@@ -1,83 +0,0 @@
-//------------------------------------------------------------------------------
-/*
-    This file is part of rippled: https://github.com/ripple/rippled
-    Copyright (c) 2012, 2013 Ripple Labs Inc.
-
-    Permission to use, copy, modify, and/or distribute this software for any
-    purpose  with  or without fee is hereby granted, provided that the above
-    copyright notice and this permission notice appear in all copies.
-
-    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
-    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
-    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-*/
-//==============================================================================
-
-#ifndef RIPPLE_CORE_SEMAPHORE_H_INCLUDED
-#define RIPPLE_CORE_SEMAPHORE_H_INCLUDED
-
-#include <condition_variable>
-#include <mutex>
-
-namespace ripple {
-
-template <class Mutex, class CondVar>
-class basic_semaphore
-{
-private:
-    Mutex m_mutex;
-    CondVar m_cond;
-    std::size_t m_count;
-
-public:
-    using size_type = std::size_t;
-
-    /** Create the semaphore, with an optional initial count.
-        If unspecified, the initial count is zero.
-    */
-    explicit basic_semaphore(size_type count = 0) : m_count(count)
-    {
-    }
-
-    /** Increment the count and unblock one waiting thread. */
-    void
-    notify()
-    {
-        std::lock_guard lock{m_mutex};
-        ++m_count;
-        m_cond.notify_one();
-    }
-
-    /** Block until notify is called. */
-    void
-    wait()
-    {
-        std::unique_lock lock{m_mutex};
-        while (m_count == 0)
-            m_cond.wait(lock);
-        --m_count;
-    }
-
-    /** Perform a non-blocking wait.
-        @return `true` If the wait would be satisfied.
-    */
-    bool
-    try_wait()
-    {
-        std::lock_guard lock{m_mutex};
-        if (m_count == 0)
-            return false;
-        --m_count;
-        return true;
-    }
-};
-
-using semaphore = basic_semaphore<std::mutex, std::condition_variable>;
-
-}  // namespace ripple
-
-#endif