feat: add V2/INVALIDATE_PATH socket message for cache invalidation

src/openvfsfuse/openvfsfuse.cpp

@@ -147,6 +147,9 @@ std::string getcallername(fuse_context *context)
 static SharedMap _jobs;
 static SocketThread _socketThread("SocketThread", _jobs);
 
+// Global fuse pointer for invalidation from socket thread
+static struct fuse *_fuseInstance = nullptr;
+
 static int _transfer_id{12};
 
 
@@ -178,6 +181,12 @@ static void *openVFSfuse_init(struct fuse_conn_info *, fuse_config *)
 {
     openvfsfuse_log("/path", "_init", 1, "**** INIT called");
 
+    // Store fuse instance for invalidation from socket thread
+    auto *ctx = fuse_get_context();
+    if (ctx) {
+        _fuseInstance = ctx->fuse;
+    }
+
     return NULL;
 }
 
@@ -725,6 +734,23 @@ static int openVFSfuse_removexattr(const char *orig_path, const char *name)
     return Xattr::removexattr(path, name);
 }
 
+void openvfsfuse_invalidate_path(const std::string &path)
+{
+    if (_fuseInstance) {
+        // Prepend "/" if not absolute (internal paths are relative)
+        std::string fusePath = path;
+        if (!fusePath.empty() && fusePath[0] != '/') {
+            fusePath = "/" + fusePath;
+        }
+        int res = fuse_invalidate_path(_fuseInstance, fusePath.c_str());
+        if (res == 0 || res == -ENOENT) {
+            openvfsfuse_log(fusePath, "invalidate", 0, "path invalidated");
+        } else {
+            openvfsfuse_log(fusePath, "invalidate", res, "invalidate failed");
+        }
+    }
+}
+
 int initializeOpenVFSFuse(openVFSfuse_Args &openVFSArgs)
 {
     const auto contextInstance = std::make_unique<VFSFuseContext>(openVFSArgs);

src/openvfsfuse/openvfsfuse.h

@@ -26,4 +26,5 @@ struct openVFSfuse_Args
 };
 
 int initializeOpenVFSFuse(openVFSfuse_Args &openVFSArgs);
+void openvfsfuse_invalidate_path(const std::string &path);
 void openvfsfuse_log(const std::string &path, const char *action, int returncode, const char *format, ...);

src/openvfsfuse/socketthread.cpp

@@ -21,6 +21,7 @@
  */
 
 #include "socketthread.h"
+#include "openvfsfuse.h"
 #include "sharedmap.h"
 #include "strtools.h"
 
@@ -230,6 +231,15 @@ void SocketThread::handleReceivedMsg(const std::string &rawmsg)
                     cout << "Setting Job ID " << id << " to result " << res << endl;
                 }
             }
+        } else if (msgType == "V2/INVALIDATE_PATH") {
+            try {
+                const auto j = json::parse(msgAttr);
+                const auto path = j["arguments"]["path"].get<string>();
+                cout << "Invalidating path: " << path << endl;
+                openvfsfuse_invalidate_path(path);
+            } catch (json::exception &e) {
+                std::cerr << "Invalid INVALIDATE_PATH message: " << msgAttr << e.what() << std::endl;
+            }
         } else if (msgType == "VERSION") {
             vector<string> attribs = StrTools::split(msgAttr, ':');
             if (attribs.size() == 3) {