feat(ffi): pin nim-ffi 0.3.0 and stop the node on destroy

library/README.md

@@ -69,6 +69,11 @@ void *logosdelivery_create_node(
 **Returns:** the context handle, or `NULL` on failure. Creation is asynchronous:
 wait for `onCreated` before you make any other call.
 
+A context whose `onCreated` reported `RET_ERR` stays live but holds no node.
+Every later call on it answers `RET_ERR` with `library is not initialized: the
+constructor failed or has not run yet`, and `logosdelivery_destroy` still
+releases it.
+
 **Example configuration JSON:**
 ```json
 {
@@ -108,7 +113,8 @@ int logosdelivery_start_node(void *ctx, LogosDeliveryScalarRawFn callback, void
 ```
 
 #### `logosdelivery_stop_node`
-Stops the node.
+Stops the node and removes the event listeners. A second call is a no-op that
+reports `RET_OK`.
 
 ```c
 int logosdelivery_stop_node(void *ctx, LogosDeliveryScalarRawFn callback, void *userData);
@@ -122,6 +128,30 @@ use `ctx` afterwards.
 int logosdelivery_destroy(void *ctx);
 ```
 
+Stops the node first if it still runs, so skipping `logosdelivery_stop_node` no
+longer leaves a live node behind. It blocks for up to 15 s at the nim-ffi
+defaults (`2 * ffiRecycleTimeoutMs + ffiTeardownTimeoutMs + 2 s`).
+
+Prefer an explicit `logosdelivery_stop_node`: a failed stop here is only logged
+(`RET_ERR` covers an invalid `ctx` and a failed context teardown, nothing else),
+and nim-ffi cancels the stop at `ffiTeardownTimeoutMs` (10 s), leaving the node
+half stopped.
+
+### Context-free calls
+
+No `ctx` and no callback: `dlsym` the symbol and read the return value.
+
+#### `logosdelivery_version`
+Version and git commit hash. Callable before `logosdelivery_create_node`, though
+the first call into the library starts the Nim runtime.
+
+```c
+const char *logosdelivery_version(void);
+```
+
+The buffer belongs to the calling thread and stays valid until that thread calls
+`logosdelivery_version` again, so copy the bytes.
+
 ### Messaging
 
 #### `logosdelivery_subscribe`

library/liblogosdelivery.h

@@ -3,8 +3,8 @@
 // The call surface is generated from the {.ffi.} annotations in library/*.nim
 // and written to generated/logosdelivery.h by `make liblogosdelivery`. That file
 // is a build artifact, not checked in, so build the library before you compile
-// against this header. This file adds the event-listener ABI, which nim-ffi
-// exports from declareLibrary but does not emit into the `abi = c` header.
+// against this header. This file adds what nim-ffi exports but leaves out of the
+// `abi = c` header: the event-listener ABI, and the `{.ffiExport.}` procs.
 #pragma once
 #ifndef __liblogosdelivery__
 #define __liblogosdelivery__
@@ -32,6 +32,10 @@ extern "C"
 {
 #endif
 
+  // Version and git commit hash. Needs no ctx. The buffer belongs to the calling
+  // thread and lasts until that thread calls this again, so copy it.
+  const char *logosdelivery_version(void);
+
   // Raw result-delivery callback used by the event API. `msg` is a byte run of
   // `len` bytes, not NUL-terminated, and is valid only for the duration of the
   // call.

library/liblogosdelivery.nim

@@ -18,6 +18,7 @@ include
   ./logos_delivery_api/node_api,
   ./logos_delivery_api/messaging_api,
   ./logos_delivery_api/debug_api,
+  ./logos_delivery_api/sync_exports,
   ./kernel_api/peer_manager_api,
   ./kernel_api/discovery_api,
   ./kernel_api/debug_node_api,

library/logos_delivery_api/node_api.nim

@@ -179,13 +179,6 @@ proc logosdelivery_create_node(
 
   return ok(lib)
 
-proc logosdelivery_destroy(self: LogosDelivery) {.ffiDtor.} =
-  ## nim-ffi runs this when the host destroys the node, before the FFI
-  ## thread can serve a later create. The forwarders registered at create
-  ## feed the C listener registry, which lives from create to destroy; the
-  ## node's broker scope carries them and dies with the node, here.
-  await self.teardownFFIEventScope()
-
 proc logosdelivery_start_node(
     self: LogosDelivery
 ): Future[Result[string, string]] {.ffi.} =
@@ -195,11 +188,26 @@ proc logosdelivery_start_node(
     return err("failed to start: " & errMsg)
   return ok("")
 
+proc stopNode(self: LogosDelivery): Future[Result[void, string]] {.async.} =
+  if not self.isRunning():
+    return ok()
+
+  await self.stop()
+
 proc logosdelivery_stop_node(
     self: LogosDelivery
 ): Future[Result[string, string]] {.ffi.} =
-  (await self.stop()).isOkOr:
+  (await self.stopNode()).isOkOr:
     let errMsg = $error
     chronicles.error "STOP_NODE failed", err = errMsg
     return err("failed to stop: " & errMsg)
   return ok("")
+
+proc logosdelivery_destroy(self: LogosDelivery) {.ffiDtor.} =
+  ## Safety net for a host that skips `stop_node` (#4108): nim-ffi recycles the
+  ## worker rather than joining it, so an unstopped node keeps running.
+  ## The forwarders registered at create live until here, with the node's
+  ## broker scope; `teardownFFIEventScope` is the other end of create.
+  (await self.stopNode()).isOkOr:
+    chronicles.error "DESTROY failed", err = error
+  await self.teardownFFIEventScope()

library/logos_delivery_api/sync_exports.nim

@@ -0,0 +1,6 @@
+## `{.ffiExport.}` entry points: no context, no callback, the value crosses the
+## C ABI directly.
+
+proc logosdelivery_version(): string {.ffiExport.} =
+  ## Same string `waku_version` answers over the context surface.
+  WakuNodeVersionString

logos_delivery.nimble

@@ -57,12 +57,12 @@ requires "nim >= 2.2.4",
   "zlib",
   # Debug & Testing
   "testutils",
-  "unittest2"
+  "unittest2",
+  # FFI
+  "ffi == 0.3.0"
 
 # Packages not on nimble (use git URLs)
 
-requires "https://github.com/logos-messaging/nim-ffi#53515de17af0ef3e88b2aec9675b8163dddc14ae" # v0.3.0-rc.2
-
 requires "https://github.com/logos-messaging/nim-sds.git#b12f5ee07c5b764303b51fb948b32a4ade1de3b5"
 
 requires "https://github.com/NagyZoltanPeter/nim-brokers.git#v3.3.0"

logos_delivery/logos_delivery.nim

@@ -216,6 +216,14 @@ proc stop*(self: LogosDelivery): Future[Result[void, string]] {.async.} =
 
   return ok()
 
+func isRunning*(self: LogosDelivery): bool =
+  ## True while a layer still holds what `stop` releases; the channel manager
+  ## needs no test, its `stop` is already a no-op when empty.
+  let transportUp =
+    not self.waku.isNil() and not self.waku.node.isNil() and self.waku.node.started
+  let messagingUp = not self.messagingClient.isNil() and self.messagingClient.started
+  transportUp or messagingUp
+
 proc isOnline*(self: LogosDelivery): Future[Result[bool, string]] {.async.} =
   if self.waku.isNil():
     return err("Waku node is not initialized")

nimble.lock

@@ -644,7 +644,7 @@
     },
     "ffi": {
       "version": "0.3.0",
-      "vcsRevision": "53515de17af0ef3e88b2aec9675b8163dddc14ae",
+      "vcsRevision": "b6c17dc822960b626d76d814de90208c0a40a44e",
       "url": "https://github.com/logos-messaging/nim-ffi",
       "downloadMethod": "git",
       "dependencies": [
@@ -655,7 +655,7 @@
         "cbor_serialization"
       ],
       "checksums": {
-        "sha1": "1d84ceaf8594f4970c5a37f916003ffc0531dc4e"
+        "sha1": "74e796df3ef39d828e014df701127edfbee459e0"
       }
     },
     "boringssl": {

nix/deps.nix

@@ -285,8 +285,8 @@
 
   ffi = pkgs.fetchgit {
     url = "https://github.com/logos-messaging/nim-ffi";
-    rev = "53515de17af0ef3e88b2aec9675b8163dddc14ae";
-    sha256 = "0ncf9j7fhgd3nswr4rh19jx77dl974sajphdl04cb602hshgj5ij";
+    rev = "b6c17dc822960b626d76d814de90208c0a40a44e";
+    sha256 = "1sjnax54j39igsxkig095grj4x3j9div4fimrmz609byhp4qdavh";
     fetchSubmodules = true;
   };
 

nix/submodules.json

@@ -56,7 +56,7 @@
   {
     "path": "vendor/nim-ffi",
     "url": "https://github.com/logos-messaging/nim-ffi",
-    "rev": "53515de17af0ef3e88b2aec9675b8163dddc14ae"
+    "rev": "b6c17dc822960b626d76d814de90208c0a40a44e"
   }
   ,
   {