1 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 /*
3  * Copyright (c) 2004, Apple Computer, Inc. and The Mozilla Foundation.
4  * All rights reserved.
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11  * notice, this list of conditions and the following disclaimer.
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13  * notice, this list of conditions and the following disclaimer in the
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15  * 3. Neither the names of Apple Computer, Inc. ("Apple") or The Mozilla
16  * Foundation ("Mozilla") nor the names of their contributors may be used
17  * to endorse or promote products derived from this software without
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20  * THIS SOFTWARE IS PROVIDED BY APPLE, MOZILLA AND THEIR CONTRIBUTORS "AS
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33 #ifndef _NP_RUNTIME_H_
34 #define _NP_RUNTIME_H_
35 
36 #include "npapi.h"
37 
38 #ifdef __cplusplus
39 extern "C" {
40 #endif
41 
42 /*
43     This API is used to facilitate binding code written in C to script
44     objects.  The API in this header does not assume the presence of a
45     user agent.  That is, it can be used to bind C code to scripting
46     environments outside of the context of a user agent.
47 
48     However, the normal use of the this API is in the context of a
49     scripting environment running in a browser or other user agent.
50     In particular it is used to support the extended Netscape
51     script-ability API for plugins (NP-SAP).  NP-SAP is an extension
52     of the Netscape plugin API.  As such we have adopted the use of
53     the "NP" prefix for this API.
54 
55     The following NP{N|P}Variables were added to the Netscape plugin
56     API (in npapi.h):
57 
58     NPNVWindowNPObject
59     NPNVPluginElementNPObject
60     NPPVpluginScriptableNPObject
61 
62     These variables are exposed through NPN_GetValue() and
63     NPP_GetValue() (respectively) and are used to establish the
64     initial binding between the user agent and native code.  The DOM
65     objects in the user agent can be examined and manipulated using
66     the NPN_ functions that operate on NPObjects described in this
67     header.
68 
69     To the extent possible the assumptions about the scripting
70     language used by the scripting environment have been minimized.
71 */
72 
73 #define NP_BEGIN_MACRO  do {
74 #define NP_END_MACRO    } while (0)
75 
76 /*
77     Objects (non-primitive data) passed between 'C' and script is
78     always wrapped in an NPObject.  The 'interface' of an NPObject is
79     described by an NPClass.
80 */
81 typedef struct NPObject NPObject;
82 typedef struct NPClass NPClass;
83 
84 typedef char NPUTF8;
85 typedef struct _NPString {
86     const NPUTF8 *UTF8Characters;
87     uint32_t UTF8Length;
88 } NPString;
89 
90 typedef enum {
91     NPVariantType_Void,
92     NPVariantType_Null,
93     NPVariantType_Bool,
94     NPVariantType_Int32,
95     NPVariantType_Double,
96     NPVariantType_String,
97     NPVariantType_Object
98 } NPVariantType;
99 
100 typedef struct _NPVariant {
101     NPVariantType type;
102     union {
103         bool boolValue;
104         int32_t intValue;
105         double doubleValue;
106         NPString stringValue;
107         NPObject *objectValue;
108     } value;
109 } NPVariant;
110 
111 /*
112     NPN_ReleaseVariantValue is called on all 'out' parameters
113     references.  Specifically it is to be called on variants that own
114     their value, as is the case with all non-const NPVariant*
115     arguments after a successful call to any methods (except this one)
116     in this API.
117 
118     After calling NPN_ReleaseVariantValue, the type of the variant
119     will be NPVariantType_Void.
120 */
121 void NPN_ReleaseVariantValue(NPVariant *variant);
122 
123 #define NPVARIANT_IS_VOID(_v)    ((_v).type == NPVariantType_Void)
124 #define NPVARIANT_IS_NULL(_v)    ((_v).type == NPVariantType_Null)
125 #define NPVARIANT_IS_BOOLEAN(_v) ((_v).type == NPVariantType_Bool)
126 #define NPVARIANT_IS_INT32(_v)   ((_v).type == NPVariantType_Int32)
127 #define NPVARIANT_IS_DOUBLE(_v)  ((_v).type == NPVariantType_Double)
128 #define NPVARIANT_IS_STRING(_v)  ((_v).type == NPVariantType_String)
129 #define NPVARIANT_IS_OBJECT(_v)  ((_v).type == NPVariantType_Object)
130 
131 #define NPVARIANT_TO_BOOLEAN(_v) ((_v).value.boolValue)
132 #define NPVARIANT_TO_INT32(_v)   ((_v).value.intValue)
133 #define NPVARIANT_TO_DOUBLE(_v)  ((_v).value.doubleValue)
134 #define NPVARIANT_TO_STRING(_v)  ((_v).value.stringValue)
135 #define NPVARIANT_TO_OBJECT(_v)  ((_v).value.objectValue)
136 
137 #define VOID_TO_NPVARIANT(_v)                                                 \
138 NP_BEGIN_MACRO                                                                \
139     (_v).type = NPVariantType_Void;                                           \
140     (_v).value.objectValue = NULL;                                            \
141 NP_END_MACRO
142 
143 #define NULL_TO_NPVARIANT(_v)                                                 \
144 NP_BEGIN_MACRO                                                                \
145     (_v).type = NPVariantType_Null;                                           \
146     (_v).value.objectValue = NULL;                                            \
147 NP_END_MACRO
148 
149 #define BOOLEAN_TO_NPVARIANT(_val, _v)                                        \
150 NP_BEGIN_MACRO                                                                \
151     (_v).type = NPVariantType_Bool;                                           \
152     (_v).value.boolValue = !!(_val);                                          \
153 NP_END_MACRO
154 
155 #define INT32_TO_NPVARIANT(_val, _v)                                          \
156 NP_BEGIN_MACRO                                                                \
157     (_v).type = NPVariantType_Int32;                                          \
158     (_v).value.intValue = _val;                                               \
159 NP_END_MACRO
160 
161 #define DOUBLE_TO_NPVARIANT(_val, _v)                                         \
162 NP_BEGIN_MACRO                                                                \
163     (_v).type = NPVariantType_Double;                                         \
164     (_v).value.doubleValue = _val;                                            \
165 NP_END_MACRO
166 
167 #define STRINGZ_TO_NPVARIANT(_val, _v)                                        \
168 NP_BEGIN_MACRO                                                                \
169     (_v).type = NPVariantType_String;                                         \
170     NPString str = { _val, uint32_t(strlen(_val)) };                          \
171     (_v).value.stringValue = str;                                             \
172 NP_END_MACRO
173 
174 #define STRINGN_TO_NPVARIANT(_val, _len, _v)                                  \
175 NP_BEGIN_MACRO                                                                \
176     (_v).type = NPVariantType_String;                                         \
177     NPString str = { _val, uint32_t(_len) };                                  \
178     (_v).value.stringValue = str;                                             \
179 NP_END_MACRO
180 
181 #define OBJECT_TO_NPVARIANT(_val, _v)                                         \
182 NP_BEGIN_MACRO                                                                \
183     (_v).type = NPVariantType_Object;                                         \
184     (_v).value.objectValue = _val;                                            \
185 NP_END_MACRO
186 
187 
188 /*
189   Type mappings (JavaScript types have been used for illustration
190     purposes):
191 
192   JavaScript       to             C (NPVariant with type:)
193   undefined                       NPVariantType_Void
194   null                            NPVariantType_Null
195   Boolean                         NPVariantType_Bool
196   Number                          NPVariantType_Double or NPVariantType_Int32
197   String                          NPVariantType_String
198   Object                          NPVariantType_Object
199 
200   C (NPVariant with type:)   to   JavaScript
201   NPVariantType_Void              undefined
202   NPVariantType_Null              null
203   NPVariantType_Bool              Boolean
204   NPVariantType_Int32             Number
205   NPVariantType_Double            Number
206   NPVariantType_String            String
207   NPVariantType_Object            Object
208 */
209 
210 typedef void *NPIdentifier;
211 
212 /*
213     NPObjects have methods and properties.  Methods and properties are
214     identified with NPIdentifiers.  These identifiers may be reflected
215     in script.  NPIdentifiers can be either strings or integers, IOW,
216     methods and properties can be identified by either strings or
217     integers (i.e. foo["bar"] vs foo[1]). NPIdentifiers can be
218     compared using ==.  In case of any errors, the requested
219     NPIdentifier(s) will be NULL. NPIdentifier lifetime is controlled
220     by the browser. Plugins do not need to worry about memory management
221     with regards to NPIdentifiers.
222 */
223 NPIdentifier NPN_GetStringIdentifier(const NPUTF8 *name);
224 void NPN_GetStringIdentifiers(const NPUTF8 **names, int32_t nameCount,
225                               NPIdentifier *identifiers);
226 NPIdentifier NPN_GetIntIdentifier(int32_t intid);
227 bool NPN_IdentifierIsString(NPIdentifier identifier);
228 
229 /*
230     The NPUTF8 returned from NPN_UTF8FromIdentifier SHOULD be freed.
231 */
232 NPUTF8 *NPN_UTF8FromIdentifier(NPIdentifier identifier);
233 
234 /*
235     Get the integer represented by identifier. If identifier is not an
236     integer identifier, the behaviour is undefined.
237 */
238 int32_t NPN_IntFromIdentifier(NPIdentifier identifier);
239 
240 /*
241     NPObject behavior is implemented using the following set of
242     callback functions.
243 
244     The NPVariant *result argument of these functions (where
245     applicable) should be released using NPN_ReleaseVariantValue().
246 */
247 typedef NPObject *(*NPAllocateFunctionPtr)(NPP npp, NPClass *aClass);
248 typedef void (*NPDeallocateFunctionPtr)(NPObject *npobj);
249 typedef void (*NPInvalidateFunctionPtr)(NPObject *npobj);
250 typedef bool (*NPHasMethodFunctionPtr)(NPObject *npobj, NPIdentifier name);
251 typedef bool (*NPInvokeFunctionPtr)(NPObject *npobj, NPIdentifier name,
252                                     const NPVariant *args, uint32_t argCount,
253                                     NPVariant *result);
254 typedef bool (*NPInvokeDefaultFunctionPtr)(NPObject *npobj,
255                                            const NPVariant *args,
256                                            uint32_t argCount,
257                                            NPVariant *result);
258 typedef bool (*NPHasPropertyFunctionPtr)(NPObject *npobj, NPIdentifier name);
259 typedef bool (*NPGetPropertyFunctionPtr)(NPObject *npobj, NPIdentifier name,
260                                          NPVariant *result);
261 typedef bool (*NPSetPropertyFunctionPtr)(NPObject *npobj, NPIdentifier name,
262                                          const NPVariant *value);
263 typedef bool (*NPRemovePropertyFunctionPtr)(NPObject *npobj,
264                                             NPIdentifier name);
265 typedef bool (*NPEnumerationFunctionPtr)(NPObject *npobj, NPIdentifier **value,
266                                          uint32_t *count);
267 typedef bool (*NPConstructFunctionPtr)(NPObject *npobj,
268                                        const NPVariant *args,
269                                        uint32_t argCount,
270                                        NPVariant *result);
271 
272 /*
273     NPObjects returned by create, retain, invoke, and getProperty pass
274     a reference count to the caller.  That is, the callee adds a
275     reference count which passes to the caller.  It is the caller's
276     responsibility to release the returned object.
277 
278     NPInvokeFunctionPtr function may return 0 to indicate a void
279     result.
280 
281     NPInvalidateFunctionPtr is called by the scripting environment
282     when the native code is shutdown.  Any attempt to message a
283     NPObject instance after the invalidate callback has been
284     called will result in undefined behavior, even if the native code
285     is still retaining those NPObject instances.  (The runtime
286     will typically return immediately, with 0 or NULL, from an attempt
287     to dispatch to a NPObject, but this behavior should not be
288     depended upon.)
289 
290     The NPEnumerationFunctionPtr function may pass an array of
291     NPIdentifiers back to the caller. The callee allocs the memory of
292     the array using NPN_MemAlloc(), and it's the caller's responsibility
293     to release it using NPN_MemFree().
294 */
295 struct NPClass
296 {
297     uint32_t structVersion;
298     NPAllocateFunctionPtr allocate;
299     NPDeallocateFunctionPtr deallocate;
300     NPInvalidateFunctionPtr invalidate;
301     NPHasMethodFunctionPtr hasMethod;
302     NPInvokeFunctionPtr invoke;
303     NPInvokeDefaultFunctionPtr invokeDefault;
304     NPHasPropertyFunctionPtr hasProperty;
305     NPGetPropertyFunctionPtr getProperty;
306     NPSetPropertyFunctionPtr setProperty;
307     NPRemovePropertyFunctionPtr removeProperty;
308     NPEnumerationFunctionPtr enumerate;
309     NPConstructFunctionPtr construct;
310 };
311 
312 #define NP_CLASS_STRUCT_VERSION      3
313 
314 #define NP_CLASS_STRUCT_VERSION_ENUM 2
315 #define NP_CLASS_STRUCT_VERSION_CTOR 3
316 
317 #define NP_CLASS_STRUCT_VERSION_HAS_ENUM(npclass)   \
318         ((npclass)->structVersion >= NP_CLASS_STRUCT_VERSION_ENUM)
319 
320 #define NP_CLASS_STRUCT_VERSION_HAS_CTOR(npclass)   \
321         ((npclass)->structVersion >= NP_CLASS_STRUCT_VERSION_CTOR)
322 
323 struct NPObject {
324     NPClass *_class;
325     uint32_t referenceCount;
326     /*
327      * Additional space may be allocated here by types of NPObjects
328      */
329 };
330 
331 /*
332     If the class has an allocate function, NPN_CreateObject invokes
333     that function, otherwise a NPObject is allocated and
334     returned. This method will initialize the referenceCount member of
335     the NPObject to 1.
336 */
337 NPObject *NPN_CreateObject(NPP npp, NPClass *aClass);
338 
339 /*
340     Increment the NPObject's reference count.
341 */
342 NPObject *NPN_RetainObject(NPObject *npobj);
343 
344 /*
345     Decremented the NPObject's reference count.  If the reference
346     count goes to zero, the class's destroy function is invoke if
347     specified, otherwise the object is freed directly.
348 */
349 void NPN_ReleaseObject(NPObject *npobj);
350 
351 /*
352     Functions to access script objects represented by NPObject.
353 
354     Calls to script objects are synchronous.  If a function returns a
355     value, it will be supplied via the result NPVariant
356     argument. Successful calls will return true, false will be
357     returned in case of an error.
358 
359     Calls made from plugin code to script must be made from the thread
360     on which the plugin was initialized.
361 */
362 
363 bool NPN_Invoke(NPP npp, NPObject *npobj, NPIdentifier methodName,
364                 const NPVariant *args, uint32_t argCount, NPVariant *result);
365 bool NPN_InvokeDefault(NPP npp, NPObject *npobj, const NPVariant *args,
366                        uint32_t argCount, NPVariant *result);
367 bool NPN_Evaluate(NPP npp, NPObject *npobj, NPString *script,
368                   NPVariant *result);
369 bool NPN_GetProperty(NPP npp, NPObject *npobj, NPIdentifier propertyName,
370                      NPVariant *result);
371 bool NPN_SetProperty(NPP npp, NPObject *npobj, NPIdentifier propertyName,
372                      const NPVariant *value);
373 bool NPN_RemoveProperty(NPP npp, NPObject *npobj, NPIdentifier propertyName);
374 bool NPN_HasProperty(NPP npp, NPObject *npobj, NPIdentifier propertyName);
375 bool NPN_HasMethod(NPP npp, NPObject *npobj, NPIdentifier methodName);
376 bool NPN_Enumerate(NPP npp, NPObject *npobj, NPIdentifier **identifier,
377                    uint32_t *count);
378 bool NPN_Construct(NPP npp, NPObject *npobj, const NPVariant *args,
379                    uint32_t argCount, NPVariant *result);
380 
381 /*
382     NPN_SetException may be called to trigger a script exception upon
383     return from entry points into NPObjects.  Typical usage:
384 
385     NPN_SetException (npobj, message);
386 */
387 void NPN_SetException(NPObject *npobj, const NPUTF8 *message);
388 
389 #ifdef __cplusplus
390 }
391 #endif
392 
393 #endif
394