WIP: Schema

Makefile

@@ -1,5 +1,5 @@
 
-all: luv.so
+all: luv
 
 libuv/include:
 	git submodule update --init libuv
@@ -10,15 +10,13 @@ luajit/src:
 build/Makefile: libuv/include luajit/src
 	cmake -H. -Bbuild
 
-build/luv.so: build/Makefile
+luv: build/Makefile
 	cmake --build build --config Release
-
-luv.so: build/luv.so
 	ln -sf build/luv.so
 
 clean:
 	rm -rf build luv.so
 
-test: luv.so
+test: luv
 	build/luajit tests/run.lua
 

src/fs.c

@@ -254,18 +254,31 @@ static int luv_fs_open(lua_State* L) {
 }
 
 static int luv_fs_read(lua_State* L) {
-  uv_file file = luaL_checkinteger(L, 1);
-  int64_t len = luaL_checkinteger(L, 2);
-  int64_t offset = luaL_checkinteger(L, 3);
+  uv_file file;
+  int64_t len, offset;
   uv_buf_t buf;
-  int ref;
   uv_fs_t* req;
-  char* data = malloc(len);
-  if (!data) return luaL_error(L, "Failure to allocate buffer");
-  buf = uv_buf_init(data, len);
-  ref = luv_check_continuation(L, 4);
-  req = lua_newuserdata(L, sizeof(*req));
-  req->data = luv_setup_req(L, ref);
+
+  lschema_check(L, (lschema_entry[]) {
+    {"file", luv_isfile},
+    {"length", luv_ispositive},
+    {"offset", luv_ispositive},
+    {"callback", luv_iscontinuation},
+    {NULL}
+  });
+
+  file = lua_tointeger(L, 1);
+  len = lua_tointeger(L, 2);
+  offset = lua_tointeger(L, 3);
+  req = luv_push_req(L, 4, sizeof(*req));
+
+  buf.base = malloc(len);
+  if (!buf.base) {
+    req->data = luv_cleanup_req(L, req->data);
+    return luaL_error(L, "Failure to allocate buffer");
+  }
+  buf.len = len;
+
   // TODO: find out why we can't just use req->ptr for the base
   ((luv_req_t*)req->data)->data = buf.base;
   FS_CALL(read, req, file, &buf, 1, offset);

src/lreq.c

@@ -16,6 +16,31 @@
  */
 #include "lreq.h"
 
+static void* luv_push_req(lua_State* L, int index, size_t size) {
+  uv_req_t* req;
+  luv_req_t* data;
+
+  data = calloc(1, sizeof(*data));
+  if (!data) luaL_error(L, "Problem allocating luv request");
+
+  req = lua_newuserdata(L, size);
+  req->data = data;
+  luaL_getmetatable(L, "uv_req");
+  lua_setmetatable(L, -2);
+
+  lua_pushvalue(L, -1);
+  data->req_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+  if (lua_isfunction(L, index)) {
+    lua_pushvalue(L, index);
+    data->callback_ref = luaL_ref(L, LUA_REGISTRYINDEX);;
+  }
+  else {
+    data->callback_ref = LUA_NOREF;
+  }
+
+  return req;
+}
+
 
 static int luv_check_continuation(lua_State* L, int index) {
   if (lua_isnoneornil(L, index)) return LUA_NOREF;
@@ -61,9 +86,10 @@ static void luv_fulfill_req(lua_State* L, luv_req_t* data, int nargs) {
   }
 }
 
-static void luv_cleanup_req(lua_State* L, luv_req_t* data) {
+static luv_req_t* luv_cleanup_req(lua_State* L, luv_req_t* data) {
   luaL_unref(L, LUA_REGISTRYINDEX, data->req_ref);
   luaL_unref(L, LUA_REGISTRYINDEX, data->callback_ref);
   free(data->data);
   free(data);
+  return NULL;
 }

src/lreq.h

@@ -25,6 +25,10 @@ typedef struct {
   void* data; // extra data
 } luv_req_t;
 
+// Create a new userdata for a uv_req_t and setup it's data member
+// Index if the stack index where the optional callback resides.
+static void* luv_push_req(lua_State* L, int index, size_t size);
+
 // Used in the top of a setup function to check the arg
 // and ref the callback to an integer.
 static int luv_check_continuation(lua_State* L, int index);
@@ -35,6 +39,6 @@ static luv_req_t* luv_setup_req(lua_State* L, int ref);
 
 static void luv_fulfill_req(lua_State* L, luv_req_t* data, int nargs);
 
-static void luv_cleanup_req(lua_State* L, luv_req_t* data);
+static luv_req_t* luv_cleanup_req(lua_State* L, luv_req_t* data);
 
 #endif

src/luv.c

@@ -16,6 +16,7 @@
  */
 
 #include "luv.h"
+#include "schema.c"
 #include "util.c"
 #include "lhandle.c"
 #include "lreq.c"

src/luv.h

@@ -67,6 +67,7 @@ static uv_loop_t* luv_loop(lua_State* L);
 // as you use a different lua_State and thread for each.
 LUALIB_API int luaopen_luv (lua_State *L);
 
+#include "schema.h"
 #include "util.h"
 #include "lhandle.h"
 #include "lreq.h"

src/schema.c

@@ -14,3 +14,31 @@
  *  limitations under the License.
  *
  */
+#include "schema.h"
+
+// Platform specefic file handle
+static int luv_isfile(lua_State* L, int index) {
+  // TODO: this should act different on windows maybe.
+  return lua_isnumber(L, index);
+}
+
+// Optional function
+static int luv_iscontinuation(lua_State* L, int index) {
+  return lua_isnone(L, index) || lua_isfunction(L, index);
+}
+
+static int luv_ispositive(lua_State* L, int index) {
+  return lua_isnumber(L, index) && lua_tonumber(L, index) >= 0;
+}
+
+void lschema_check(lua_State* L, lschema_entry schema[]) {
+  int num = lua_gettop(L) - 1;
+  int i;
+  for (i = 0; schema[i].name;) {
+    lschema_entry entry = schema[i++];
+    luaL_argcheck(L, entry.checker(L, i), i, entry.name);
+  }
+  if (num > i) {
+    luaL_argerror(L, i, "Too many arguments");
+  }
+}

src/schema.h

@@ -0,0 +1,16 @@
+#ifndef LSCHEMA_H
+#define LSCHEMA_H
+
+#include "luv.h"
+
+typedef const struct {
+  const char* name;
+  int (*checker)(lua_State* L, int index);
+} lschema_entry;
+
+static int luv_isfile(lua_State* L, int index);
+static int luv_iscontinuation(lua_State* L, int index);
+static int luv_ispositive(lua_State* L, int index);
+void lschema_check(lua_State* L, lschema_entry schema[]);
+
+#endif