toolkit/components/ctypes/ctypes.cpp

   1 /* -*-  Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "ctypes.h"
   7 #include "jsapi.h"
   8 #include "mozilla/ModuleUtils.h"
   9 #include "nsMemory.h"
  10 #include "nsString.h"
  11 #include "nsNativeCharsetUtils.h"
  12 #include "mozilla/Preferences.h"
  13 #include "mozJSComponentLoader.h"
  14 #include "nsZipArchive.h"
  15
  16 #define JSCTYPES_CONTRACTID \
  17   "@mozilla.org/jsctypes;1"
  18
  19
  20 #define JSCTYPES_CID \
  21 { 0xc797702, 0x1c60, 0x4051, { 0x9d, 0xd7, 0x4d, 0x74, 0x5, 0x60, 0x56, 0x42 } }
  22
  23 namespace mozilla {
  24 namespace ctypes {
  25
  26 static char*
  27 UnicodeToNative(JSContext *cx, const jschar *source, size_t slen)
  28 {
  29   nsAutoCString native;
  30   nsDependentString unicode(reinterpret_cast<const char16_t*>(source), slen);
  31   nsresult rv = NS_CopyUnicodeToNative(unicode, native);
  32   if (NS_FAILED(rv)) {
  33     JS_ReportError(cx, "could not convert string to native charset");
  34     return nullptr;
  35   }
  36
  37   char* result = static_cast<char*>(JS_malloc(cx, native.Length() + 1));
  38   if (!result)
  39     return nullptr;
  40
  41   memcpy(result, native.get(), native.Length() + 1);
  42   return result;
  43 }
  44
  45 static JSCTypesCallbacks sCallbacks = {
  46   UnicodeToNative
  47 };
  48
  49 NS_GENERIC_FACTORY_CONSTRUCTOR(Module)
  50
  51 NS_IMPL_ISUPPORTS(Module, nsIXPCScriptable)
  52
  53 Module::Module()
  54 {
  55 }
  56
  57 Module::~Module()
  58 {
  59 }
  60
  61 #define XPC_MAP_CLASSNAME Module
  62 #define XPC_MAP_QUOTED_CLASSNAME "Module"
  63 #define XPC_MAP_WANT_CALL
  64 #define XPC_MAP_FLAGS nsIXPCScriptable::WANT_CALL
  65 #include "xpc_map_end.h"
  66
  67 static bool
  68 SealObjectAndPrototype(JSContext* cx, JS::Handle<JSObject *> parent, const char* name)
  69 {
  70   JS::Rooted<JS::Value> prop(cx);
  71   if (!JS_GetProperty(cx, parent, name, &prop))
  72     return false;
  73
  74   if (prop.isUndefined()) {
  75     // Pretend we sealed the object.
  76     return true;
  77   }
  78
  79   JS::Rooted<JSObject*> obj(cx, prop.toObjectOrNull());
  80   if (!JS_GetProperty(cx, obj, "prototype", &prop))
  81     return false;
  82
  83   JS::Rooted<JSObject*> prototype(cx, prop.toObjectOrNull());
  84   return JS_FreezeObject(cx, obj) && JS_FreezeObject(cx, prototype);
  85 }
  86
  87 static bool
  88 InitAndSealCTypesClass(JSContext* cx, JS::Handle<JSObject*> global)
  89 {
  90   // Init the ctypes object.
  91   if (!JS_InitCTypesClass(cx, global))
  92     return false;
  93
  94   // Set callbacks for charset conversion and such.
  95   JS::Rooted<JS::Value> ctypes(cx);
  96   if (!JS_GetProperty(cx, global, "ctypes", &ctypes))
  97     return false;
  98
  99   JS_SetCTypesCallbacks(ctypes.toObjectOrNull(), &sCallbacks);
 100
 101   // Seal up Object, Function, Array and Error and their prototypes.  (This
 102   // single object instance is shared amongst everyone who imports the ctypes
 103   // module.)
 104   if (!SealObjectAndPrototype(cx, global, "Object") ||
 105       !SealObjectAndPrototype(cx, global, "Function") ||
 106       !SealObjectAndPrototype(cx, global, "Array") ||
 107       !SealObjectAndPrototype(cx, global, "Error"))
 108     return false;
 109
 110   // Finally, seal the global object, for good measure. (But not recursively;
 111   // this breaks things.)
 112   return JS_FreezeObject(cx, global);
 113 }
 114
 115 NS_IMETHODIMP
 116 Module::Call(nsIXPConnectWrappedNative* wrapper,
 117              JSContext* cx,
 118              JSObject* obj,
 119              const JS::CallArgs& args,
 120              bool* _retval)
 121 {
 122   mozJSComponentLoader* loader = mozJSComponentLoader::Get();
 123   JS::Rooted<JSObject*> targetObj(cx);
 124   nsresult rv = loader->FindTargetObject(cx, &targetObj);
 125   NS_ENSURE_SUCCESS(rv, rv);
 126
 127   *_retval = InitAndSealCTypesClass(cx, targetObj);
 128   return NS_OK;
 129 }
 130
 131 }
 132 }
 133
 134 NS_DEFINE_NAMED_CID(JSCTYPES_CID);
 135
 136 static const mozilla::Module::CIDEntry kCTypesCIDs[] = {
 137   { &kJSCTYPES_CID, false, nullptr, mozilla::ctypes::ModuleConstructor },
 138   { nullptr }
 139 };
 140
 141 static const mozilla::Module::ContractIDEntry kCTypesContracts[] = {
 142   { JSCTYPES_CONTRACTID, &kJSCTYPES_CID },
 143   { nullptr }
 144 };
 145
 146 static const mozilla::Module kCTypesModule = {
 147   mozilla::Module::kVersion,
 148   kCTypesCIDs,
 149   kCTypesContracts
 150 };
 151
 152 NSMODULE_DEFN(jsctypes) = &kCTypesModule;