hyprctl: added --follow option to rolliglog (#6325)

Co-authored-by: Крылов Александр <aleksandr.krylov@hyperus.team>

src/debug/HyprCtl.cpp

@@ -28,6 +28,7 @@ using namespace Hyprutils::String;
 #include "../devices/IKeyboard.hpp"
 #include "../devices/ITouch.hpp"
 #include "../devices/Tablet.hpp"
+#include "debug/RollingLogFollow.hpp"
 #include "config/ConfigManager.hpp"
 #include "helpers/MiscFunctions.hpp"
 
@@ -1732,6 +1733,46 @@ std::string CHyprCtl::makeDynamicCall(const std::string& input) {
     return getReply(input);
 }
 
+bool successWrite(int fd, const std::string& data, bool needLog = true) {
+    if (write(fd, data.c_str(), data.length()) > 0)
+        return true;
+
+    if (errno == EAGAIN)
+        return true;
+
+    if (needLog)
+        Debug::log(ERR, "Couldn't write to socket. Error: " + std::string(strerror(errno)));
+
+    return false;
+}
+
+void runWritingDebugLogThread(const int conn) {
+    using namespace std::chrono_literals;
+    Debug::log(LOG, "In followlog thread, got connection, start writing: {}", conn);
+    //will be finished, when reading side close connection
+    std::thread([conn]() {
+        while (Debug::RollingLogFollow::Get().IsRunning()) {
+            if (Debug::RollingLogFollow::Get().isEmpty(conn)) {
+                std::this_thread::sleep_for(1000ms);
+                continue;
+            }
+
+            auto line = Debug::RollingLogFollow::Get().GetLog(conn);
+            if (!successWrite(conn, line))
+                // We cannot write, when connection is closed. So thread will successfully exit by itself
+                break;
+
+            std::this_thread::sleep_for(100ms);
+        }
+        close(conn);
+        Debug::RollingLogFollow::Get().StopFor(conn);
+    }).detach();
+}
+
+bool isFollowUpRollingLogRequest(const std::string& request) {
+    return request.contains("rollinglog") && request.contains("f");
+}
+
 int hyprCtlFDTick(int fd, uint32_t mask, void* data) {
     if (mask & WL_EVENT_ERROR || mask & WL_EVENT_HANGUP)
         return 0;
@@ -1775,9 +1816,15 @@ int hyprCtlFDTick(int fd, uint32_t mask, void* data) {
         reply = "Err: " + std::string(e.what());
     }
 
-    write(ACCEPTEDCONNECTION, reply.c_str(), reply.length());
+    successWrite(ACCEPTEDCONNECTION, reply);
 
-    close(ACCEPTEDCONNECTION);
+    if (isFollowUpRollingLogRequest(request)) {
+        Debug::log(LOG, "Followup rollinglog request received. Starting thread to write to socket.");
+        Debug::RollingLogFollow::Get().StartFor(ACCEPTEDCONNECTION);
+        runWritingDebugLogThread(ACCEPTEDCONNECTION);
+        Debug::log(LOG, Debug::RollingLogFollow::Get().DebugInfo());
+    } else
+        close(ACCEPTEDCONNECTION);
 
     if (g_pConfigManager->m_bWantsMonitorReload)
         g_pConfigManager->ensureMonitorStatus();

src/debug/Log.cpp

@@ -1,6 +1,7 @@
 #include "Log.hpp"
 #include "../defines.hpp"
 #include "../Compositor.hpp"
+#include "RollingLogFollow.hpp"
 
 #include <fstream>
 #include <iostream>
@@ -73,6 +74,9 @@ void Debug::log(LogLevel level, std::string str) {
     if (rollingLog.size() > ROLLING_LOG_SIZE)
         rollingLog = rollingLog.substr(rollingLog.size() - ROLLING_LOG_SIZE);
 
+    if (RollingLogFollow::Get().IsRunning())
+        RollingLogFollow::Get().AddLog(str);
+
     if (!disableLogs || !**disableLogs) {
         // log to a file
         std::ofstream ofs;

src/debug/RollingLogFollow.hpp

@@ -0,0 +1,65 @@
+#pragma once
+
+#include <shared_mutex>
+
+namespace Debug {
+    struct RollingLogFollow {
+        std::unordered_map<int, std::string> socketToRollingLogFollowQueue;
+        std::shared_mutex                    m;
+        bool                                 running                    = false;
+        static constexpr size_t              ROLLING_LOG_FOLLOW_TOO_BIG = 8192;
+
+        // Returns true if the queue is empty for the given socket
+        bool isEmpty(int socket) {
+            std::shared_lock<std::shared_mutex> r(m);
+            return socketToRollingLogFollowQueue[socket].empty();
+        }
+
+        std::string DebugInfo() {
+            std::shared_lock<std::shared_mutex> r(m);
+            return std::format("RollingLogFollow, got {} connections", socketToRollingLogFollowQueue.size());
+        }
+
+        std::string GetLog(int socket) {
+            std::unique_lock<std::shared_mutex> w(m);
+
+            const std::string                   ret = socketToRollingLogFollowQueue[socket];
+            socketToRollingLogFollowQueue[socket]   = "";
+
+            return ret;
+        };
+
+        void AddLog(std::string log) {
+            std::unique_lock<std::shared_mutex> w(m);
+            running = true;
+            std::vector<int> to_erase;
+            for (const auto& p : socketToRollingLogFollowQueue)
+                socketToRollingLogFollowQueue[p.first] += log + "\n";
+        }
+
+        bool IsRunning() {
+            std::shared_lock<std::shared_mutex> r(m);
+            return running;
+        }
+
+        void StopFor(int socket) {
+            std::unique_lock<std::shared_mutex> w(m);
+            socketToRollingLogFollowQueue.erase(socket);
+            if (socketToRollingLogFollowQueue.empty())
+                running = false;
+        }
+
+        void StartFor(int socket) {
+            std::unique_lock<std::shared_mutex> w(m);
+            socketToRollingLogFollowQueue[socket] = std::format("[LOG] Following log to socket: {} started\n", socket);
+            running                               = true;
+        }
+
+        static RollingLogFollow& Get() {
+            static RollingLogFollow     instance;
+            static std::mutex           gm;
+            std::lock_guard<std::mutex> lock(gm);
+            return instance;
+        };
+    };
+}