1 files changed, 88 insertions, 21 deletions

diff --git a/src/nvim/msgpack_rpc/channel.c b/src/nvim/msgpack_rpc/channel.c
index cd64e14976..68ac35bc4e 100644
--- a/src/nvim/msgpack_rpc/channel.c
+++ b/src/nvim/msgpack_rpc/channel.c
@@ -12,6 +12,7 @@
 #include "nvim/api/vim.h"
 #include "nvim/api/ui.h"
 #include "nvim/msgpack_rpc/channel.h"
+#include "nvim/msgpack_rpc/server.h"
 #include "nvim/event/loop.h"
 #include "nvim/event/libuv_process.h"
 #include "nvim/event/rstream.h"
@@ -28,6 +29,7 @@
 #include "nvim/map.h"
 #include "nvim/log.h"
 #include "nvim/misc1.h"
+#include "nvim/path.h"
 #include "nvim/lib/kvec.h"
 #include "nvim/os/input.h"
 
@@ -41,7 +43,8 @@
 typedef enum {
   kChannelTypeSocket,
   kChannelTypeProc,
-  kChannelTypeStdio
+  kChannelTypeStdio,
+  kChannelTypeInternal
 } ChannelType;
 
 typedef struct {
@@ -125,7 +128,7 @@ uint64_t channel_from_process(Process *proc, uint64_t id)
 
   wstream_init(proc->in, 0);
   rstream_init(proc->out, 0);
-  rstream_start(proc->out, parse_msgpack, channel);
+  rstream_start(proc->out, receive_msgpack, channel);
 
   return channel->id;
 }
@@ -142,7 +145,36 @@ void channel_from_connection(SocketWatcher *watcher)
   channel->data.stream.internal_data = channel;
   wstream_init(&channel->data.stream, 0);
   rstream_init(&channel->data.stream, CHANNEL_BUFFER_SIZE);
-  rstream_start(&channel->data.stream, parse_msgpack, channel);
+  rstream_start(&channel->data.stream, receive_msgpack, channel);
+}
+
+uint64_t channel_connect(bool tcp, const char *address,
+                         int timeout, const char **error)
+{
+  if (!tcp) {
+    char *path = fix_fname(address);
+    if (server_owns_pipe_address(path)) {
+      // avoid deadlock
+      xfree(path);
+      return channel_create_internal();
+    }
+    xfree(path);
+  }
+
+  Channel *channel = register_channel(kChannelTypeSocket, 0, NULL);
+  if (!socket_connect(&main_loop, &channel->data.stream,
+                      tcp, address, timeout, error)) {
+    decref(channel);
+    return 0;
+  }
+
+  incref(channel);  // close channel only after the stream is closed
+  channel->data.stream.internal_close_cb = close_cb;
+  channel->data.stream.internal_data = channel;
+  wstream_init(&channel->data.stream, 0);
+  rstream_init(&channel->data.stream, CHANNEL_BUFFER_SIZE);
+  rstream_start(&channel->data.stream, receive_msgpack, channel);
+  return channel->id;
 }
 
 /// Sends event/arguments to channel
@@ -305,11 +337,20 @@ void channel_from_stdio(void)
   incref(channel);  // stdio channels are only closed on exit
   // read stream
   rstream_init_fd(&main_loop, &channel->data.std.in, 0, CHANNEL_BUFFER_SIZE);
-  rstream_start(&channel->data.std.in, parse_msgpack, channel);
+  rstream_start(&channel->data.std.in, receive_msgpack, channel);
   // write stream
   wstream_init_fd(&main_loop, &channel->data.std.out, 1, 0);
 }
 
+/// Creates a loopback channel. This is used to avoid deadlock
+/// when an instance connects to its own named pipe.
+uint64_t channel_create_internal(void)
+{
+  Channel *channel = register_channel(kChannelTypeInternal, 0, NULL);
+  incref(channel);  // internal channel lives until process exit
+  return channel->id;
+}
+
 void channel_process_exit(uint64_t id, int status)
 {
   Channel *channel = pmap_get(uint64_t)(channels, id);
@@ -318,8 +359,8 @@ void channel_process_exit(uint64_t id, int status)
   decref(channel);
 }
 
-static void parse_msgpack(Stream *stream, RBuffer *rbuf, size_t c, void *data,
-    bool eof)
+static void receive_msgpack(Stream *stream, RBuffer *rbuf, size_t c,
+                            void *data, bool eof)
 {
   Channel *channel = data;
   incref(channel);
@@ -329,7 +370,7 @@ static void parse_msgpack(Stream *stream, RBuffer *rbuf, size_t c, void *data,
     char buf[256];
     snprintf(buf, sizeof(buf), "ch %" PRIu64 " was closed by the client",
              channel->id);
-    call_set_error(channel, buf);
+    call_set_error(channel, buf, WARNING_LOG_LEVEL);
     goto end;
   }
 
@@ -341,6 +382,14 @@ static void parse_msgpack(Stream *stream, RBuffer *rbuf, size_t c, void *data,
   rbuffer_read(rbuf, msgpack_unpacker_buffer(channel->unpacker), count);
   msgpack_unpacker_buffer_consumed(channel->unpacker, count);
 
+  parse_msgpack(channel);
+
+end:
+  decref(channel);
+}
+
+static void parse_msgpack(Channel *channel)
+{
   msgpack_unpacked unpacked;
   msgpack_unpacked_init(&unpacked);
   msgpack_unpack_return result;
@@ -360,11 +409,11 @@ static void parse_msgpack(Stream *stream, RBuffer *rbuf, size_t c, void *data,
                  "ch %" PRIu64 " returned a response with an unknown request "
                  "id. Ensure the client is properly synchronized",
                  channel->id);
-        call_set_error(channel, buf);
+        call_set_error(channel, buf, ERROR_LOG_LEVEL);
       }
       msgpack_unpacked_destroy(&unpacked);
       // Bail out from this event loop iteration
-      goto end;
+      return;
     }
 
     handle_request(channel, &unpacked.data);
@@ -388,11 +437,9 @@ static void parse_msgpack(Stream *stream, RBuffer *rbuf, size_t c, void *data,
                            "This error can also happen when deserializing "
                            "an object with high level of nesting");
   }
-
-end:
-  decref(channel);
 }
 
+
 static void handle_request(Channel *channel, msgpack_object *request)
   FUNC_ATTR_NONNULL_ALL
 {
@@ -412,7 +459,7 @@ static void handle_request(Channel *channel, msgpack_object *request)
       snprintf(buf, sizeof(buf),
                "ch %" PRIu64 " sent an invalid message, closed.",
                channel->id);
-      call_set_error(channel, buf);
+      call_set_error(channel, buf, ERROR_LOG_LEVEL);
     }
     api_clear_error(&error);
     return;
@@ -485,7 +532,7 @@ static void on_request_event(void **argv)
 
 static bool channel_write(Channel *channel, WBuffer *buffer)
 {
-  bool success;
+  bool success = false;
 
   if (channel->closed) {
     wstream_release_wbuffer(buffer);
@@ -502,8 +549,11 @@ static bool channel_write(Channel *channel, WBuffer *buffer)
     case kChannelTypeStdio:
       success = wstream_write(&channel->data.std.out, buffer);
       break;
-    default:
-      abort();
+    case kChannelTypeInternal:
+      incref(channel);
+      CREATE_EVENT(channel->events, internal_read_event, 2, channel, buffer);
+      success = true;
+      break;
   }
 
   if (!success) {
@@ -514,12 +564,28 @@ static bool channel_write(Channel *channel, WBuffer *buffer)
              "Before returning from a RPC call, ch %" PRIu64 " was "
              "closed due to a failed write",
              channel->id);
-    call_set_error(channel, buf);
+    call_set_error(channel, buf, ERROR_LOG_LEVEL);
   }
 
   return success;
 }
 
+static void internal_read_event(void **argv)
+{
+  Channel *channel = argv[0];
+  WBuffer *buffer = argv[1];
+
+  msgpack_unpacker_reserve_buffer(channel->unpacker, buffer->size);
+  memcpy(msgpack_unpacker_buffer(channel->unpacker),
+         buffer->data, buffer->size);
+  msgpack_unpacker_buffer_consumed(channel->unpacker, buffer->size);
+
+  parse_msgpack(channel);
+
+  decref(channel);
+  wstream_release_wbuffer(buffer);
+}
+
 static void send_error(Channel *channel, uint64_t id, char *err)
 {
   Error e = ERROR_INIT;
@@ -636,8 +702,9 @@ static void close_channel(Channel *channel)
       stream_close(&channel->data.std.out, NULL, NULL);
       multiqueue_put(main_loop.fast_events, exit_event, 1, channel);
       return;
-    default:
-      abort();
+    case kChannelTypeInternal:
+      // nothing to free.
+      break;
   }
 
   decref(channel);
@@ -728,9 +795,9 @@ static void complete_call(msgpack_object *obj, Channel *channel)
   }
 }
 
-static void call_set_error(Channel *channel, char *msg)
+static void call_set_error(Channel *channel, char *msg, int loglevel)
 {
-  ELOG("RPC: %s", msg);
+  LOG(loglevel, "RPC: %s", msg);
   for (size_t i = 0; i < kv_size(channel->call_stack); i++) {
     ChannelCallFrame *frame = kv_A(channel->call_stack, i);
     frame->returned = true;