ppapi/c/pp_var.h

// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef PPAPI_C_PP_VAR_H_
#define PPAPI_C_PP_VAR_H_

/**
 * @file
 * Defines the API ...
 *
 * @addtogroup PP
 * @{
 */

#include "ppapi/c/pp_bool.h"
#include "ppapi/c/pp_macros.h"
#include "ppapi/c/pp_stdint.h"

typedef enum {
  PP_VARTYPE_UNDEFINED,
  PP_VARTYPE_NULL,
  PP_VARTYPE_BOOL,
  PP_VARTYPE_INT32,
  PP_VARTYPE_DOUBLE,
  PP_VARTYPE_STRING,
  PP_VARTYPE_OBJECT
} PP_VarType;

PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_VarType, 4);

/**
 * Do not rely on having a predictable and reproducible
 * int/double differentiation.
 * JavaScript has a "number" type for holding a number, and
 * does not differentiate between floating point and integer numbers. The
 * JavaScript library will try to optimize operations by using integers
 * when possible, but could end up with doubles depending on how the number
 * was arrived at.
 *
 * Your best bet is to have a wrapper for variables
 * that always gets out the type you expect, converting as necessary.
 */
struct PP_Var {
  PP_VarType type;
  union {
    PP_Bool as_bool;
    int32_t as_int;
    double as_double;

    /**
     * Internal ID for strings and objects. The identifier is an opaque handle
     * assigned by the browser to the plugin. It is guaranteed never to be 0,
     * so a plugin can initialize this ID to 0 to indicate a "NULL handle."
     */
    int64_t as_id;
  } value;
};

PP_INLINE struct PP_Var PP_MakeUndefined() {
  struct PP_Var result = { PP_VARTYPE_UNDEFINED, {PP_FALSE} };
  return result;
}

PP_INLINE struct PP_Var PP_MakeNull() {
  struct PP_Var result = { PP_VARTYPE_NULL, {PP_FALSE} };
  return result;
}

PP_INLINE struct PP_Var PP_MakeBool(PP_Bool value) {
  struct PP_Var result = { PP_VARTYPE_BOOL, {PP_FALSE} };
  result.value.as_bool = value;
  return result;
}

PP_INLINE struct PP_Var PP_MakeInt32(int32_t value) {
  struct PP_Var result = { PP_VARTYPE_INT32, {PP_FALSE} };
  result.value.as_int = value;
  return result;
}

PP_INLINE struct PP_Var PP_MakeDouble(double value) {
  struct PP_Var result = { PP_VARTYPE_DOUBLE, {PP_FALSE} };
  result.value.as_double = value;
  return result;
}

/**
 * @}
 * End addtogroup PP
 */
#endif  // PPAPI_C_PP_VAR_H_