Fix spawn error handling

Makefile

@@ -7,14 +7,15 @@ LIB_SRC = $(shell pwd)/lib
 LIBUV_SRC = $(shell pwd)/3rd_party/libuv-1.51.0
 LIBUV_BUILD_DIR = $(MIX_APP_PATH)/cmake_libuv-1.51.0
 LIBUV_INSTALL_DIR = $(MIX_APP_PATH)/libuv
-LIBUV_A = $(LIBUV_INSTALL_DIR)/lib/libuv_a.a
+LIBUV_A = $(LIBUV_INSTALL_DIR)/lib/libuv.a
 LIBUV_CMAKE_SOURCE_DIR = $(LIBUV_INSTALL_DIR)/cmake/libuv
 NIF_BUILD_DIR = $(MIX_APP_PATH)/cmake_expty
+NIF_SOURCES = $(shell find "$(C_SRC)" -type f) CMakeLists.txt
 
 DEFAULT_JOBS ?= 1
 MAKE_BUILD_FLAGS ?= -j$(DEFAULT_JOBS)
 
-.DEFAULT_GLOBAL := build
+.DEFAULT_GOAL := build
 
 build: $(NIF_SO)
 	@ echo > /dev/null
@@ -32,9 +33,8 @@ $(LIBUV_A): $(PRIV_DIR)
 		cmake --install . ; \
 	fi
 
-$(NIF_SO): $(PRIV_DIR) $(LIBUV_A)
-	@ if [ ! -e "$(NIF_SO)" ]; then \
-		mkdir -p "$(NIF_BUILD_DIR)" && \
+$(NIF_SO): $(PRIV_DIR) $(LIBUV_A) $(NIF_SOURCES)
+	@ mkdir -p "$(NIF_BUILD_DIR)" && \
 		cd "$(NIF_BUILD_DIR)" && \
 		cmake "$(shell pwd)" -D CMAKE_INSTALL_PREFIX="$(PRIV_DIR)" \
 			-D LIBUV_INCLUDE_DIR="$(LIBUV_INSTALL_DIR)/include" \
@@ -46,8 +46,7 @@ $(NIF_SO): $(PRIV_DIR) $(LIBUV_A)
 			-D PRIV_DIR="$(PRIV_DIR)" \
 			-D ERTS_INCLUDE_DIR="$(ERTS_INCLUDE_DIR)" && \
 		cmake --build . $(MAKE_BUILD_FLAGS) && \
-		cmake --install . ; \
-	fi
+		cmake --install .
 
 cleanup:
 	@ rm -rf "$(PRIV_DIR)"

README.md

@@ -1,4 +1,4 @@
-**(Warning: this project is still WIP, there are a lot of things (like proper cleanups) not done yet, and right now it shows a minimal working product (without proper cleanups yet!) with Kino. Use at your own risk.**
+**Warning:** this project is still WIP. Some cleanup paths are still incomplete, and the Kino integration currently demonstrates a minimal working product. Use at your own risk.
 
 **Any help/PR is welcome!**
 
@@ -15,8 +15,8 @@
 <td>
 
 ```elixir
-iex> pty = ExPTY.spawn("tty", [], on_data: fn _, _, data -> IO.write(data) end)
-#PID<0.229.0>
+iex> {:ok, pty} = ExPTY.spawn("tty", [], on_data: fn _, _, data -> IO.write(data) end)
+{:ok, #PID<0.229.0>}
 /dev/ttys001
 ```
 
@@ -100,7 +100,7 @@ by adding `ExPTY` to your list of dependencies in `mix.exs`:
 ```elixir
 def deps do
   [
-    {:expty, "~> 0.1.0"}
+    {:expty, "~> 0.2.2"}
   ]
 end
 ```

c_src/unix/pty.cpp

@@ -630,6 +630,7 @@ pty_pipesocket_fn(void *data) {
       const size_t buf_size = 1024;
       char buffer[buf_size] = {'\0'};
       ssize_t bytes_read = read(fd, buffer, buf_size);
+
       if (bytes_read == 0) {
         pipesocket->fd_closed = true;
         close(fd);
@@ -648,15 +649,17 @@ pty_pipesocket_fn(void *data) {
 
       ERL_NIF_TERM dataread;
       unsigned char * ptr;
+      size_t bytes_read_size = static_cast<size_t>(bytes_read);
 
       ErlNifEnv * msg_env = enif_alloc_env();
-      if ((ptr = enif_make_new_binary(msg_env, bytes_read, &dataread)) != nullptr) {
-        memcpy(ptr, buffer, bytes_read);
+      if ((ptr = enif_make_new_binary(msg_env, bytes_read_size, &dataread)) != nullptr) {
+        memcpy(ptr, buffer, bytes_read_size);
         enif_send(NULL, &pipesocket->process, msg_env, enif_make_tuple2(msg_env,
           nif::atom(msg_env, "data"),
           dataread
         ));
       }
+
       enif_free_env(msg_env);
     }
   }
@@ -670,10 +673,11 @@ size_t pty_pipesocket::write(void * data, size_t len) {
   }
 
   uv_mutex_lock(&this->mutex);
+  const char *buffer = static_cast<const char *>(data);
   size_t bytes_to_write = len, bytes_written = 0, buffer_size = 1024, nbytes = 0;
   size_t retry = 3;
 
-  while (true) {
+  while (bytes_written < len) {
     nbytes = buffer_size;
     if (buffer_size > bytes_to_write) {
       nbytes = bytes_to_write;
@@ -683,18 +687,30 @@ size_t pty_pipesocket::write(void * data, size_t len) {
       break;
     }
 
-    ssize_t bytes_written_cur = ::write(this->fd, static_cast<char *>(data) + bytes_written, nbytes);
+    ssize_t bytes_written_cur = ::write(this->fd, buffer + bytes_written, nbytes);
     if (bytes_written_cur > 0) {
       bytes_written += bytes_written_cur;
       bytes_to_write -= bytes_written_cur;
+      retry = 3;
       if (bytes_written == len) {
         break;
       }
-    } else {
-      if (retry-- > 0) {
-        usleep(10);
-      }
+      continue;
     }
+
+    if (bytes_written_cur == -1 && errno == EINTR) {
+      continue;
+    }
+
+    if (bytes_written_cur == -1 &&
+        (errno == EAGAIN || errno == EWOULDBLOCK) &&
+        retry > 0) {
+      retry--;
+      usleep(10);
+      continue;
+    }
+
+    break;
   }
 
   uv_mutex_unlock(&this->mutex);