update for latest n-api changes

PR-URL: nodejs/node-addon-api#144
Reviewed-By: Sampson Gao <sampsong@ca.ibm.com>

napi-inl.h

@@ -1204,7 +1204,7 @@ inline Function Function::New(napi_env env,
 
   napi_value value;
   napi_status status = napi_create_function(
-    env, utf8name, -1, CbData::Wrapper, callbackData, &value);
+    env, utf8name, NAPI_AUTO_LENGTH, CbData::Wrapper, callbackData, &value);
   NAPI_THROW_IF_FAILED(env, status, Function());
   return Function(env, value);
 }
@@ -1476,7 +1476,7 @@ inline Error Error::New(napi_env env, const std::string& message) {
 }
 
 inline NAPI_NO_RETURN void Error::Fatal(const char* location, const char* message) {
-  napi_fatal_error(location, -1, message, -1);
+  napi_fatal_error(location, NAPI_AUTO_LENGTH, message, NAPI_AUTO_LENGTH);
 }
 
 inline Error::Error() : ObjectReference(), _message(nullptr) {
@@ -2312,7 +2312,8 @@ inline Function ObjectWrap<T>::DefineClass(
     void* data) {
   napi_value value;
   napi_status status = napi_define_class(
-    env, utf8name, -1, T::ConstructorCallbackWrapper, data, properties.size(),
+    env, utf8name, NAPI_AUTO_LENGTH,
+    T::ConstructorCallbackWrapper, data, properties.size(),
     reinterpret_cast<const napi_property_descriptor*>(properties.begin()), &value);
   NAPI_THROW_IF_FAILED(env, status, Function());
 
@@ -2327,7 +2328,8 @@ inline Function ObjectWrap<T>::DefineClass(
     void* data) {
   napi_value value;
   napi_status status = napi_define_class(
-    env, utf8name, -1, T::ConstructorCallbackWrapper, data, properties.size(),
+    env, utf8name, NAPI_AUTO_LENGTH,
+    T::ConstructorCallbackWrapper, data, properties.size(),
     reinterpret_cast<const napi_property_descriptor*>(properties.data()), &value);
   NAPI_THROW_IF_FAILED(env, status, Function());
 
@@ -2683,7 +2685,7 @@ inline AsyncWorker::AsyncWorker(const Object& receiver, const Function& callback
 
   napi_value resource_id;
   napi_status status = napi_create_string_latin1(
-    _env, "generic", -1, &resource_id);
+    _env, "generic", NAPI_AUTO_LENGTH, &resource_id);
   NAPI_THROW_IF_FAILED(_env, status);
 
   status = napi_create_async_work(

src/node_api.cc

@@ -8,14 +8,14 @@
  *
  ******************************************************************************/
 
-#include "node_internals.h"
 #include <node_buffer.h>
 #include <node_object_wrap.h>
 #include <string.h>
 #include <algorithm>
 #include <cmath>
 #include <vector>
 #include "node_api.h"
+#include "node_internals.h"
 
 #define NAPI_VERSION  1
 
@@ -117,16 +117,23 @@ struct napi_env__ {
   CHECK_TO_TYPE((env), Boolean, (context), (result), (src), \
     napi_boolean_expected)
 
+// n-api defines NAPI_AUTO_LENGHTH as the indicator that a string
+// is null terminated. For V8 the equivalent is -1. The assert
+// validates that our cast of NAPI_AUTO_LENGTH results in -1 as
+// needed by V8.
 #define CHECK_NEW_FROM_UTF8_LEN(env, result, str, len)                   \
   do {                                                                   \
+    static_assert(static_cast<int>(NAPI_AUTO_LENGTH) == -1,              \
+                  "Casting NAPI_AUTO_LENGTH to int must result in -1");  \
     auto str_maybe = v8::String::NewFromUtf8(                            \
-        (env)->isolate, (str), v8::NewStringType::kInternalized, (len)); \
+        (env)->isolate, (str), v8::NewStringType::kInternalized,         \
+        static_cast<int>(len));                                          \
     CHECK_MAYBE_EMPTY((env), str_maybe, napi_generic_failure);           \
     (result) = str_maybe.ToLocalChecked();                               \
   } while (0)
 
 #define CHECK_NEW_FROM_UTF8(env, result, str) \
-  CHECK_NEW_FROM_UTF8_LEN((env), (result), (str), -1)
+  CHECK_NEW_FROM_UTF8_LEN((env), (result), (str), NAPI_AUTO_LENGTH)
 
 #define GET_RETURN_STATUS(env)      \
   (!try_catch.HasCaught() ? napi_ok \
@@ -918,21 +925,26 @@ NAPI_NO_RETURN void napi_fatal_error(const char* location,
                                      size_t location_len,
                                      const char* message,
                                      size_t message_len) {
-  char* location_string = const_cast<char*>(location);
-  char* message_string = const_cast<char*>(message);
-  if (location_len != -1) {
-    location_string = reinterpret_cast<char*>(
-        malloc(location_len * sizeof(char) + 1));
-    strncpy(location_string, location, location_len);
-    location_string[location_len] = '\0';
+  std::string location_string;
+  std::string message_string;
+
+  if (location_len != NAPI_AUTO_LENGTH) {
+    location_string.assign(
+        const_cast<char*>(location), location_len);
+  } else {
+    location_string.assign(
+        const_cast<char*>(location), strlen(location));
   }
-  if (message_len != -1) {
-    message_string = reinterpret_cast<char*>(
-        malloc(message_len * sizeof(char) + 1));
-    strncpy(message_string, message, message_len);
-    message_string[message_len] = '\0';
+
+  if (message_len != NAPI_AUTO_LENGTH) {
+    message_string.assign(
+        const_cast<char*>(message), message_len);
+  } else {
+    message_string.assign(
+        const_cast<char*>(message), strlen(message));
   }
-  node::FatalError(location_string, message_string);
+
+  node::FatalError(location_string.c_str(), message_string.c_str());
 }
 
 napi_status napi_create_function(napi_env env,
@@ -3285,7 +3297,6 @@ napi_status napi_adjust_external_memory(napi_env env,
                                         int64_t change_in_bytes,
                                         int64_t* adjusted_value) {
   CHECK_ENV(env);
-  CHECK_ARG(env, &change_in_bytes);
   CHECK_ARG(env, adjusted_value);
 
   *adjusted_value = env->isolate->AdjustAmountOfExternalAllocatedMemory(

src/node_api.h

@@ -100,6 +100,8 @@ typedef struct {
 #define NAPI_MODULE(modname, regfunc) \
   NAPI_MODULE_X(modname, regfunc, NULL, 0)
 
+#define NAPI_AUTO_LENGTH SIZE_MAX
+
 EXTERN_C_START
 
 NAPI_EXTERN void napi_module_register(napi_module* mod);