michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: set ts=2 sw=2 et tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "ctypes/Library.h"
michael@0: 
michael@0: #include "prlink.h"
michael@0: 
michael@0: #include "ctypes/CTypes.h"
michael@0: 
michael@0: namespace js {
michael@0: namespace ctypes {
michael@0: 
michael@0: /*******************************************************************************
michael@0: ** JSAPI function prototypes
michael@0: *******************************************************************************/
michael@0: 
michael@0: namespace Library
michael@0: {
michael@0:   static void Finalize(JSFreeOp *fop, JSObject* obj);
michael@0: 
michael@0:   static bool Close(JSContext* cx, unsigned argc, jsval* vp);
michael@0:   static bool Declare(JSContext* cx, unsigned argc, jsval* vp);
michael@0: }
michael@0: 
michael@0: /*******************************************************************************
michael@0: ** JSObject implementation
michael@0: *******************************************************************************/
michael@0: 
michael@0: typedef Rooted<JSFlatString*>    RootedFlatString;
michael@0: 
michael@0: static const JSClass sLibraryClass = {
michael@0:   "Library",
michael@0:   JSCLASS_HAS_RESERVED_SLOTS(LIBRARY_SLOTS),
michael@0:   JS_PropertyStub, JS_DeletePropertyStub, JS_PropertyStub, JS_StrictPropertyStub,
michael@0:   JS_EnumerateStub,JS_ResolveStub, JS_ConvertStub, Library::Finalize
michael@0: };
michael@0: 
michael@0: #define CTYPESFN_FLAGS \
michael@0:   (JSPROP_ENUMERATE | JSPROP_READONLY | JSPROP_PERMANENT)
michael@0: 
michael@0: static const JSFunctionSpec sLibraryFunctions[] = {
michael@0:   JS_FN("close",   Library::Close,   0, CTYPESFN_FLAGS),
michael@0:   JS_FN("declare", Library::Declare, 0, CTYPESFN_FLAGS),
michael@0:   JS_FS_END
michael@0: };
michael@0: 
michael@0: bool
michael@0: Library::Name(JSContext* cx, unsigned argc, jsval *vp)
michael@0: {
michael@0:   CallArgs args = CallArgsFromVp(argc, vp);
michael@0:   if (args.length() != 1) {
michael@0:     JS_ReportError(cx, "libraryName takes one argument");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   Value arg = args[0];
michael@0:   JSString* str = nullptr;
michael@0:   if (JSVAL_IS_STRING(arg)) {
michael@0:     str = JSVAL_TO_STRING(arg);
michael@0:   }
michael@0:   else {
michael@0:     JS_ReportError(cx, "name argument must be a string");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   AutoString resultString;
michael@0:   AppendString(resultString, DLL_PREFIX);
michael@0:   AppendString(resultString, str);
michael@0:   AppendString(resultString, DLL_SUFFIX);
michael@0: 
michael@0:   JSString *result = JS_NewUCStringCopyN(cx, resultString.begin(),
michael@0:                                          resultString.length());
michael@0:   if (!result)
michael@0:     return false;
michael@0: 
michael@0:   args.rval().setString(result);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: JSObject*
michael@0: Library::Create(JSContext* cx, jsval path_, JSCTypesCallbacks* callbacks)
michael@0: {
michael@0:   RootedValue path(cx, path_);
michael@0:   RootedObject libraryObj(cx,
michael@0:                           JS_NewObject(cx, &sLibraryClass, NullPtr(), NullPtr()));
michael@0:   if (!libraryObj)
michael@0:     return nullptr;
michael@0: 
michael@0:   // initialize the library
michael@0:   JS_SetReservedSlot(libraryObj, SLOT_LIBRARY, PRIVATE_TO_JSVAL(nullptr));
michael@0: 
michael@0:   // attach API functions
michael@0:   if (!JS_DefineFunctions(cx, libraryObj, sLibraryFunctions))
michael@0:     return nullptr;
michael@0: 
michael@0:   if (!JSVAL_IS_STRING(path)) {
michael@0:     JS_ReportError(cx, "open takes a string argument");
michael@0:     return nullptr;
michael@0:   }
michael@0: 
michael@0:   PRLibSpec libSpec;
michael@0:   RootedFlatString pathStr(cx, JS_FlattenString(cx, JSVAL_TO_STRING(path)));
michael@0:   if (!pathStr)
michael@0:     return nullptr;
michael@0: #ifdef XP_WIN
michael@0:   // On Windows, converting to native charset may corrupt path string.
michael@0:   // So, we have to use Unicode path directly.
michael@0:   char16ptr_t pathChars = JS_GetFlatStringChars(pathStr);
michael@0:   if (!pathChars)
michael@0:     return nullptr;
michael@0: 
michael@0:   libSpec.value.pathname_u = pathChars;
michael@0:   libSpec.type = PR_LibSpec_PathnameU;
michael@0: #else
michael@0:   // Convert to platform native charset if the appropriate callback has been
michael@0:   // provided.
michael@0:   char* pathBytes;
michael@0:   if (callbacks && callbacks->unicodeToNative) {
michael@0:     pathBytes =
michael@0:       callbacks->unicodeToNative(cx, pathStr->chars(), pathStr->length());
michael@0:     if (!pathBytes)
michael@0:       return nullptr;
michael@0: 
michael@0:   } else {
michael@0:     // Fallback: assume the platform native charset is UTF-8. This is true
michael@0:     // for Mac OS X, Android, and probably Linux.
michael@0:     size_t nbytes =
michael@0:       GetDeflatedUTF8StringLength(cx, pathStr->chars(), pathStr->length());
michael@0:     if (nbytes == (size_t) -1)
michael@0:       return nullptr;
michael@0: 
michael@0:     pathBytes = static_cast<char*>(JS_malloc(cx, nbytes + 1));
michael@0:     if (!pathBytes)
michael@0:       return nullptr;
michael@0: 
michael@0:     ASSERT_OK(DeflateStringToUTF8Buffer(cx, pathStr->chars(),
michael@0:                 pathStr->length(), pathBytes, &nbytes));
michael@0:     pathBytes[nbytes] = 0;
michael@0:   }
michael@0: 
michael@0:   libSpec.value.pathname = pathBytes;
michael@0:   libSpec.type = PR_LibSpec_Pathname;
michael@0: #endif
michael@0: 
michael@0:   PRLibrary* library = PR_LoadLibraryWithFlags(libSpec, 0);
michael@0: 
michael@0:   if (!library) {
michael@0: #ifdef XP_WIN
michael@0:     JS_ReportError(cx, "couldn't open library %hs", pathChars);
michael@0: #else
michael@0:     JS_ReportError(cx, "couldn't open library %s", pathBytes);
michael@0:     JS_free(cx, pathBytes);
michael@0: #endif
michael@0:     return nullptr;
michael@0:   }
michael@0: 
michael@0: #ifndef XP_WIN
michael@0:   JS_free(cx, pathBytes);
michael@0: #endif
michael@0: 
michael@0:   // stash the library
michael@0:   JS_SetReservedSlot(libraryObj, SLOT_LIBRARY, PRIVATE_TO_JSVAL(library));
michael@0: 
michael@0:   return libraryObj;
michael@0: }
michael@0: 
michael@0: bool
michael@0: Library::IsLibrary(JSObject* obj)
michael@0: {
michael@0:   return JS_GetClass(obj) == &sLibraryClass;
michael@0: }
michael@0: 
michael@0: PRLibrary*
michael@0: Library::GetLibrary(JSObject* obj)
michael@0: {
michael@0:   JS_ASSERT(IsLibrary(obj));
michael@0: 
michael@0:   jsval slot = JS_GetReservedSlot(obj, SLOT_LIBRARY);
michael@0:   return static_cast<PRLibrary*>(JSVAL_TO_PRIVATE(slot));
michael@0: }
michael@0: 
michael@0: static void
michael@0: UnloadLibrary(JSObject* obj)
michael@0: {
michael@0:   PRLibrary* library = Library::GetLibrary(obj);
michael@0:   if (library)
michael@0:     PR_UnloadLibrary(library);
michael@0: }
michael@0: 
michael@0: void
michael@0: Library::Finalize(JSFreeOp *fop, JSObject* obj)
michael@0: {
michael@0:   UnloadLibrary(obj);
michael@0: }
michael@0: 
michael@0: bool
michael@0: Library::Open(JSContext* cx, unsigned argc, jsval *vp)
michael@0: {
michael@0:   CallArgs args = CallArgsFromVp(argc, vp);
michael@0:   JSObject* ctypesObj = JS_THIS_OBJECT(cx, vp);
michael@0:   if (!ctypesObj)
michael@0:     return false;
michael@0:   if (!IsCTypesGlobal(ctypesObj)) {
michael@0:     JS_ReportError(cx, "not a ctypes object");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (args.length() != 1 || args[0].isUndefined()) {
michael@0:     JS_ReportError(cx, "open requires a single argument");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   JSObject* library = Create(cx, args[0], GetCallbacks(ctypesObj));
michael@0:   if (!library)
michael@0:     return false;
michael@0: 
michael@0:   args.rval().setObject(*library);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: Library::Close(JSContext* cx, unsigned argc, jsval* vp)
michael@0: {
michael@0:   CallArgs args = CallArgsFromVp(argc, vp);
michael@0:   JSObject* obj = JS_THIS_OBJECT(cx, vp);
michael@0:   if (!obj)
michael@0:     return false;
michael@0:   if (!IsLibrary(obj)) {
michael@0:     JS_ReportError(cx, "not a library");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (args.length() != 0) {
michael@0:     JS_ReportError(cx, "close doesn't take any arguments");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   // delete our internal objects
michael@0:   UnloadLibrary(obj);
michael@0:   JS_SetReservedSlot(obj, SLOT_LIBRARY, PRIVATE_TO_JSVAL(nullptr));
michael@0: 
michael@0:   args.rval().setUndefined();
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: bool
michael@0: Library::Declare(JSContext* cx, unsigned argc, jsval* vp)
michael@0: {
michael@0:   CallArgs args = CallArgsFromVp(argc, vp);
michael@0:   RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
michael@0:   if (!obj)
michael@0:     return false;
michael@0:   if (!IsLibrary(obj)) {
michael@0:     JS_ReportError(cx, "not a library");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   PRLibrary* library = GetLibrary(obj);
michael@0:   if (!library) {
michael@0:     JS_ReportError(cx, "library not open");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   // We allow two API variants:
michael@0:   // 1) library.declare(name, abi, returnType, argType1, ...)
michael@0:   //    declares a function with the given properties, and resolves the symbol
michael@0:   //    address in the library.
michael@0:   // 2) library.declare(name, type)
michael@0:   //    declares a symbol of 'type', and resolves it. The object that comes
michael@0:   //    back will be of type 'type', and will point into the symbol data.
michael@0:   //    This data will be both readable and writable via the usual CData
michael@0:   //    accessors. If 'type' is a PointerType to a FunctionType, the result will
michael@0:   //    be a function pointer, as with 1).
michael@0:   if (args.length() < 2) {
michael@0:     JS_ReportError(cx, "declare requires at least two arguments");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (!args[0].isString()) {
michael@0:     JS_ReportError(cx, "first argument must be a string");
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   RootedObject fnObj(cx, nullptr);
michael@0:   RootedObject typeObj(cx);
michael@0:   bool isFunction = args.length() > 2;
michael@0:   if (isFunction) {
michael@0:     // Case 1).
michael@0:     // Create a FunctionType representing the function.
michael@0:     fnObj = FunctionType::CreateInternal(cx,
michael@0:               args[1], args[2], &args.array()[3], args.length() - 3);
michael@0:     if (!fnObj)
michael@0:       return false;
michael@0: 
michael@0:     // Make a function pointer type.
michael@0:     typeObj = PointerType::CreateInternal(cx, fnObj);
michael@0:     if (!typeObj)
michael@0:       return false;
michael@0:   } else {
michael@0:     // Case 2).
michael@0:     if (args[1].isPrimitive() ||
michael@0:         !CType::IsCType(args[1].toObjectOrNull()) ||
michael@0:         !CType::IsSizeDefined(args[1].toObjectOrNull())) {
michael@0:       JS_ReportError(cx, "second argument must be a type of defined size");
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     typeObj = args[1].toObjectOrNull();
michael@0:     if (CType::GetTypeCode(typeObj) == TYPE_pointer) {
michael@0:       fnObj = PointerType::GetBaseType(typeObj);
michael@0:       isFunction = fnObj && CType::GetTypeCode(fnObj) == TYPE_function;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   void* data;
michael@0:   PRFuncPtr fnptr;
michael@0:   JSString* nameStr = args[0].toString();
michael@0:   AutoCString symbol;
michael@0:   if (isFunction) {
michael@0:     // Build the symbol, with mangling if necessary.
michael@0:     FunctionType::BuildSymbolName(nameStr, fnObj, symbol);
michael@0:     AppendString(symbol, "\0");
michael@0: 
michael@0:     // Look up the function symbol.
michael@0:     fnptr = PR_FindFunctionSymbol(library, symbol.begin());
michael@0:     if (!fnptr) {
michael@0:       JS_ReportError(cx, "couldn't find function symbol in library");
michael@0:       return false;
michael@0:     }
michael@0:     data = &fnptr;
michael@0: 
michael@0:   } else {
michael@0:     // 'typeObj' is another data type. Look up the data symbol.
michael@0:     AppendString(symbol, nameStr);
michael@0:     AppendString(symbol, "\0");
michael@0: 
michael@0:     data = PR_FindSymbol(library, symbol.begin());
michael@0:     if (!data) {
michael@0:       JS_ReportError(cx, "couldn't find symbol in library");
michael@0:       return false;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   RootedObject result(cx, CData::Create(cx, typeObj, obj, data, isFunction));
michael@0:   if (!result)
michael@0:     return false;
michael@0: 
michael@0:   args.rval().setObject(*result);
michael@0: 
michael@0:   // Seal the CData object, to prevent modification of the function pointer.
michael@0:   // This permanently associates this object with the library, and avoids
michael@0:   // having to do things like reset SLOT_REFERENT when someone tries to
michael@0:   // change the pointer value.
michael@0:   // XXX This will need to change when bug 541212 is fixed -- CData::ValueSetter
michael@0:   // could be called on a sealed object.
michael@0:   if (isFunction && !JS_FreezeObject(cx, result))
michael@0:     return false;
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: }
michael@0: }
michael@0: