From eca990920af7dc034ca1a263416aea8f3f9251d0 Mon Sep 17 00:00:00 2001
From: Jaume Pujantell <jaume.pujantell@collabora.com>
Date: Wed, 29 Nov 2023 15:22:13 +0100
Subject: [PATCH] add logic to sapwn threads intead of processes

Added code that spawns forkit and lokit in threads instead of new processes.

Signed-off-by: Jaume Pujantell <jaume.pujantell@collabora.com>
Change-Id: I6b6ad6dccfedaf28ebd0d68851205c540b9a0317
---
 common/Log.cpp         |  5 +--
 kit/ForKit.cpp         | 82 ++++++++++++++++++++++++------------------
 wsd/coolwsd-inproc.cpp | 17 +++++++++
 3 files changed, 68 insertions(+), 36 deletions(-)

diff --git a/common/Log.cpp b/common/Log.cpp
index e730aa891..d1847ee4d 100644
--- a/common/Log.cpp
+++ b/common/Log.cpp
@@ -611,8 +611,9 @@ namespace Log
     void shutdown()
     {
 #if !MOBILEAPP
-        assert(ThreadLocalBufferCount <= 1 &&
-               "Unstopped threads may have unflushed buffered log entries");
+        if (!Util::isKitInProcess())
+            assert(ThreadLocalBufferCount <= 1 &&
+                   "Unstopped threads may have unflushed buffered log entries");
 
         IsShutdown = true;
 
diff --git a/kit/ForKit.cpp b/kit/ForKit.cpp
index 7a26cc9fb..8368ff732 100644
--- a/kit/ForKit.cpp
+++ b/kit/ForKit.cpp
@@ -385,6 +385,21 @@ static void cleanupChildren()
     }
 }
 
+void sleepForDebugger()
+{
+    if (std::getenv("SLEEPKITFORDEBUGGER"))
+    {
+        const size_t delaySecs = std::stoul(std::getenv("SLEEPKITFORDEBUGGER"));
+        if (delaySecs > 0)
+        {
+            std::cerr << "Kit: Sleeping " << delaySecs
+                      << " seconds to give you time to attach debugger to process " << getpid()
+                      << std::endl;
+            std::this_thread::sleep_for(std::chrono::seconds(delaySecs));
+        }
+    }
+}
+
 static int createLibreOfficeKit(const std::string& childRoot,
                                 const std::string& sysTemplate,
                                 const std::string& loTemplate,
@@ -403,49 +418,48 @@ static int createLibreOfficeKit(const std::string& childRoot,
                                                       << spareKitId << '.');
     const auto startForkingTime = std::chrono::steady_clock::now();
 
-    const pid_t pid = fork();
-    if (!pid)
+    pid_t pid = 0;
+    if (Util::isKitInProcess())
     {
-        // Child
-
-        // Close the pipe from coolwsd
-        close(0);
-
-#ifndef KIT_IN_PROCESS
-        UnitKit::get().postFork();
-#endif
-
-        if (std::getenv("SLEEPKITFORDEBUGGER"))
-        {
-            const size_t delaySecs = std::stoul(std::getenv("SLEEPKITFORDEBUGGER"));
-            if (delaySecs > 0)
-            {
-                std::cerr << "Kit: Sleeping " << delaySecs
-                          << " seconds to give you time to attach debugger to process "
-                          << getpid() << std::endl;
-                std::this_thread::sleep_for(std::chrono::seconds(delaySecs));
-            }
-        }
-
-        lokit_main(childRoot, jailId, sysTemplate, loTemplate, NoCapsForKit, NoSeccomp,
-                   queryVersion, DisplayVersion, spareKitId);
+        std::thread([childRoot, jailId, sysTemplate, loTemplate, queryVersion] {
+            sleepForDebugger();
+            lokit_main(childRoot, jailId, sysTemplate, loTemplate, true, true, queryVersion,
+                       DisplayVersion, spareKitId);
+        })
+            .detach();
     }
     else
     {
-        // Parent
-        if (pid < 0)
+        pid = fork();
+        if (!pid)
         {
-            LOG_SYS("Fork failed");
+            // Child
+
+            // Close the pipe from coolwsd
+            close(0);
+
+            UnitKit::get().postFork();
+
+            sleepForDebugger();
+
+            lokit_main(childRoot, jailId, sysTemplate, loTemplate, NoCapsForKit, NoSeccomp,
+                       queryVersion, DisplayVersion, spareKitId);
         }
         else
         {
-            LOG_INF("Forked kit [" << pid << ']');
-            childJails[pid] = childRoot + jailId;
-        }
+            // Parent
+            if (pid < 0)
+            {
+                LOG_SYS("Fork failed");
+            }
+            else
+            {
+                LOG_INF("Forked kit [" << pid << ']');
+                childJails[pid] = childRoot + jailId;
+            }
 
-#ifndef KIT_IN_PROCESS
-        UnitKit::get().launchedKit(pid);
-#endif
+            UnitKit::get().launchedKit(pid);
+        }
     }
 
     const auto duration = (std::chrono::steady_clock::now() - startForkingTime);
diff --git a/wsd/coolwsd-inproc.cpp b/wsd/coolwsd-inproc.cpp
index 25f06b906..9dc6fa80f 100644
--- a/wsd/coolwsd-inproc.cpp
+++ b/wsd/coolwsd-inproc.cpp
@@ -15,5 +15,22 @@
 int createForkit(const std::string& forKitPath, const StringVector& args)
 {
     // create forkit in a thread
+    int argc = args.size() + 1;
+    char** argv = new char*[argc];
+
+    argv[0] = new char[forKitPath.size() + 1];
+    std::strcpy(argv[0], forKitPath.c_str());
+    for (size_t i = 0; i < args.size(); ++i)
+    {
+        argv[i + 1] = new char[args[i].size() + 1];
+        std::strcpy(argv[i + 1], args[i].c_str());
+    }
+
+    std::thread([argc, argv] {
+        Util::setThreadName("forkit");
+        forkit_main(argc, argv);
+    })
+        .detach();
+
     return 0;
 }