Implementing common external function handlers in jerry-ext

Add `extfunc` module to `jerry-ext` to contain implementation of
commonly used external function handlers: `assert`, `gc`, and
`print`.

JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu

Author: akosthekiss

jerry-ext/extfunc/extfunc-assert.c

@@ -0,0 +1,41 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jerryscript-ext/extfunc.h"
+#include "jerryscript-port.h"
+
+/**
+ * Add assert for scripts. The routine calls jerry_port_fatal on assertion failure.
+ *
+ * @return true - if only one argument was passed and the argument is a boolean true.
+ */
+jerry_value_t
+jerryx_extfunc_assert (const jerry_value_t func_obj_val __attribute__((unused)), /**< function object */
+                       const jerry_value_t this_p __attribute__((unused)), /**< this arg */
+                       const jerry_value_t args_p[], /**< function arguments */
+                       const jerry_length_t args_cnt) /**< number of function arguments */
+{
+  if (args_cnt == 1
+      && jerry_value_is_boolean (args_p[0])
+      && jerry_get_boolean_value (args_p[0]))
+  {
+    return jerry_create_boolean (true);
+  }
+  else
+  {
+    jerry_port_log (JERRY_LOG_LEVEL_ERROR, "Script Error: assertion failed\n");
+    jerry_port_fatal (ERR_FAILED_INTERNAL_ASSERTION);
+  }
+} /* jerryx_extfunc_assert */

jerry-ext/extfunc/extfunc-gc.c

@@ -0,0 +1,31 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jerryscript-ext/extfunc.h"
+
+/**
+ * Expose garbage collector to scripts.
+ *
+ * @return undefined.
+ */
+jerry_value_t
+jerryx_extfunc_gc (const jerry_value_t func_obj_val __attribute__((unused)), /**< function object */
+                   const jerry_value_t this_p __attribute__((unused)), /**< this arg */
+                   const jerry_value_t args_p[] __attribute__((unused)), /**< function arguments */
+                   const jerry_length_t args_cnt __attribute__((unused))) /**< number of function arguments */
+{
+  jerry_gc ();
+  return jerry_create_undefined ();
+} /* jerryx_extfunc_gc */

jerry-ext/extfunc/extfunc-print.c

@@ -0,0 +1,94 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jerryscript-ext/extfunc.h"
+
+
+/**
+ * Provide a 'print' implementation for scripts.
+ *
+ * The routine converts all of its arguments to strings and outputs them
+ * char-by-char using jerryx_port_extfunc_print_char.
+ *
+ * The NUL character is output as "\u0000", other characters are output
+ * bytewise.
+ *
+ * @return undefined - if all arguments could be converted to strings,
+ *         error - otherwise.
+ */
+jerry_value_t
+jerryx_extfunc_print (const jerry_value_t func_obj_val __attribute__((unused)), /**< function object */
+                      const jerry_value_t this_p __attribute__((unused)), /**< this arg */
+                      const jerry_value_t args_p[], /**< function arguments */
+                      const jerry_length_t args_cnt) /**< number of function arguments */
+{
+  static const char *null_str = "\\u0000";
+
+  jerry_value_t ret_val = jerry_create_undefined ();
+
+  for (jerry_length_t arg_index = 0;
+       jerry_value_is_undefined (ret_val) && arg_index < args_cnt;
+       arg_index++)
+  {
+    jerry_value_t str_val = jerry_value_to_string (args_p[arg_index]);
+
+    if (!jerry_value_has_error_flag (str_val))
+    {
+      if (arg_index != 0)
+      {
+        jerryx_extfunc_print_char (' ');
+      }
+
+      jerry_size_t substr_size;
+      jerry_length_t substr_pos = 0;
+      jerry_char_t substr_buf[256];
+
+      while ((substr_size = jerry_substring_to_char_buffer (str_val,
+                                                            substr_pos,
+                                                            substr_pos + 256,
+                                                            substr_buf,
+                                                            256)) != 0)
+      {
+        for (jerry_size_t chr_index = 0; chr_index < substr_size; chr_index++)
+        {
+          char chr = (char) substr_buf[chr_index];
+          if (chr == '\0')
+          {
+            for (jerry_size_t null_index = 0; null_str[null_index] != 0; null_index++)
+            {
+              jerryx_port_extfunc_print_char (null_str[null_index]);
+            }
+          }
+          else
+          {
+            jerryx_port_extfunc_print_char (chr);
+          }
+        }
+
+        substr_pos += substr_size;
+      }
+
+      jerry_release_value (str_val);
+    }
+    else
+    {
+      ret_val = str_val;
+    }
+  }
+
+  jerryx_port_extfunc_print_char ('\n');
+
+  return ret_val;
+} /* jerryx_extfunc_print */

jerry-ext/extfunc/extfunc-register.c

@@ -0,0 +1,43 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jerryscript-ext/extfunc.h"
+
+
+/**
+ * Register a JavaScript function in the global object.
+ *
+ * Note:
+ *      returned value must be freed with jerry_release_value, when it is no longer needed.
+ *
+ * @return true value - if the operation was successful
+ *         value marked with error flag - otherwise
+ */
+jerry_value_t
+jerryx_extfunc_register_global_function (const jerry_char_t *name_p, /**< name of the function */
+                                         jerry_external_handler_t handler_p) /**< function callback */
+{
+  jerry_value_t global_obj_val = jerry_get_global_object ();
+  jerry_value_t function_name_val = jerry_create_string (name_p);
+  jerry_value_t function_val = jerry_create_external_function (handler_p);
+
+  jerry_value_t result_val = jerry_set_property (global_obj_val, function_name_val, function_val);
+
+  jerry_release_value (function_val);
+  jerry_release_value (function_name_val);
+  jerry_release_value (global_obj_val);
+
+  return result_val;
+} /* register_js_function */

jerry-ext/include/jerryscript-ext/extfunc.h

@@ -0,0 +1,57 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef JERRYX_EXTFUNC_H
+#define JERRYX_EXTFUNC_H
+
+#include "jerryscript.h"
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif /* __cplusplus */
+
+/*
+ * Handler registration helper
+ */
+
+jerry_value_t jerryx_extfunc_register_global_function (const jerry_char_t *name_p, jerry_external_handler_t handler_p);
+
+/*
+ * Common external function handlers
+ */
+
+jerry_value_t jerryx_extfunc_assert (const jerry_value_t func_obj_val, const jerry_value_t this_p,
+                                     const jerry_value_t args_p[], const jerry_length_t args_cnt);
+jerry_value_t jerryx_extfunc_gc (const jerry_value_t func_obj_val, const jerry_value_t this_p,
+                                 const jerry_value_t args_p[], const jerry_length_t args_cnt);
+jerry_value_t jerryx_extfunc_print (const jerry_value_t func_obj_val, const jerry_value_t this_p,
+                                    const jerry_value_t args_p[], const jerry_length_t args_cnt);
+
+/*
+ * JerryX ExtFunc Port API
+ */
+
+/**
+ * Print a single character.
+ *
+ * @param c the character to print.
+ */
+void jerryx_port_extfunc_print_char (char c);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* !JERRYX_EXTFUNC_H */