Fix wineserver tracking matching unrelated wine prefixes

findWineserver() was scanning /proc for ANY wineserver owned by the
current user. If the user had other wine processes running (e.g. winecfg
under ~/.wine), Fluorine would latch onto that unrelated wineserver and
never declare the game finished.

Now reads WINEPREFIX from the launched process's /proc/<pid>/environ and
passes it to findWineserver(), which filters candidates by matching
their WINEPREFIX against the game's prefix path.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 57 insertions, 11 deletions

diff --git a/src/src/processrunner.cpp b/src/src/processrunner.cpp
index 9d444f1..724886b 100644
--- a/src/src/processrunner.cpp
+++ b/src/src/processrunner.cpp
@@ -515,11 +515,33 @@ QStringList readProcCmdline(pid_t pid) {
   return parts;

 }

 

-// Find a wineserver process owned by the current user.  Wineserver stays

-// alive as long as any Wine process in the prefix is running, making it

-// the most reliable way to detect when a game has truly exited — even when

-// launcher .exe's (nvse_loader, skse_loader, etc.) exit before the actual game.

-pid_t findWineserver() {

+// Read a specific environment variable from /proc/<pid>/environ.

+// The environ file is NUL-separated KEY=VALUE pairs.

+QString readProcEnvVar(pid_t pid, const char *varName) {

+  QFile f(QString("/proc/%1/environ").arg(pid));

+  if (!f.open(QIODevice::ReadOnly)) {

+    return {};

+  }

+

+  const QByteArray data = f.readAll();

+  const QByteArray prefix = QByteArray(varName) + '=';

+  for (const QByteArray &entry : data.split('\0')) {

+    if (entry.startsWith(prefix)) {

+      return QString::fromUtf8(entry.mid(prefix.size()));

+    }

+  }

+  return {};

+}

+

+// Find a wineserver process owned by the current user that belongs to the

+// given WINEPREFIX.  When expectedPrefix is empty, returns the first

+// wineserver owned by us (legacy behaviour).

+//

+// Wineserver stays alive as long as any Wine process in the prefix is

+// running, making it the most reliable way to detect when a game has truly

+// exited — even when launcher .exe's (nvse_loader, skse_loader, etc.) exit

+// before the actual game.

+pid_t findWineserver(const QString &expectedPrefix = {}) {

   const uid_t myUid = ::getuid();

   DIR *proc = opendir("/proc");

   if (!proc) return 0;

@@ -537,11 +559,26 @@ pid_t findWineserver() {
 

     // Verify it's owned by us.

     struct stat st;

-    if (::stat(QString("/proc/%1").arg(pid).toStdString().c_str(), &st) == 0 &&

-        st.st_uid == myUid) {

-      result = pid;

-      break;

+    if (::stat(QString("/proc/%1").arg(pid).toStdString().c_str(), &st) != 0 ||

+        st.st_uid != myUid) {

+      continue;

+    }

+

+    // If a prefix filter was given, verify this wineserver belongs to it.

+    // A wineserver without WINEPREFIX in its environ is using the default

+    // ~/.wine prefix, which is never the game prefix — skip it too.

+    if (!expectedPrefix.isEmpty()) {

+      const QString wsPrefix = readProcEnvVar(pid, "WINEPREFIX");

+      if (wsPrefix.isEmpty() ||

+          QDir(wsPrefix).canonicalPath() != QDir(expectedPrefix).canonicalPath()) {

+        log::debug("skipping wineserver {} (prefix '{}' != expected '{}')",

+                   pid, wsPrefix.toStdString(), expectedPrefix.toStdString());

+        continue;

+      }

     }

+

+    result = pid;

+    break;

   }

   closedir(proc);

   return result;

@@ -730,6 +767,15 @@ ProcessRunner::Results waitForPid(pid_t pid, LPDWORD exitCode,
     return ProcessRunner::Error;

   }

 

+  // Capture the WINEPREFIX from the launched process so we can filter

+  // wineserver lookups to the correct prefix.  Without this, Fluorine

+  // would track ANY wineserver owned by the user (e.g. one running

+  // winecfg under ~/.wine while the game uses a different prefix).

+  const QString winePrefix = readProcEnvVar(pid, "WINEPREFIX");

+  if (!winePrefix.isEmpty()) {

+    log::debug("process {} has WINEPREFIX='{}'", pid, winePrefix.toStdString());

+  }

+

   // startDetached() creates a non-child process, so waitpid() will fail with

   // ECHILD. Detect this on the first call and switch to kill(pid, 0) polling

   // which works for any process owned by the same user.

@@ -781,7 +827,7 @@ ProcessRunner::Results waitForPid(pid_t pid, LPDWORD exitCode,
         displayPid = lastTrackedPid;

         displayName = readProcComm(lastTrackedPid);

       } else {

-        const pid_t ws = findWineserver();

+        const pid_t ws = findWineserver(winePrefix);

         if (ws > 0) {

           log::info("tracked process exited, waiting for wineserver {}", ws);

           lastTrackedPid = ws;

@@ -817,7 +863,7 @@ ProcessRunner::Results waitForPid(pid_t pid, LPDWORD exitCode,
           // try falling back to wineserver — the real game may still be running

           // (e.g. nvse_loader exits after spawning FalloutNV.exe).

           if (seenTrackedProcess) {

-            const pid_t ws = findWineserver();

+            const pid_t ws = findWineserver(winePrefix);

             if (ws > 0 && ws != pollPid) {

               log::info("polled process {} exited, falling back to wineserver {}", pollPid, ws);

               lastTrackedPid = ws;