Visual Studio 2013 offers an interesting static code analysis. Here's a warning I get that I can't get rid of:
C6102 Using 'Attributes' from failed function call at line '1031'
'Attributes' is not initialized 1031
Skip this branch, (assume '<branch condition>' is false) 1031
'Attributes' is used, but may not have been initialized 1037.
The code is simple:
BOOL GetDeviceVersionNumber(int Index, PUSHORT version)
{
/*
This function returns TRUE is it succeeds
and puts Version number in VersionNumber
*/
HANDLE h = GetHandleByIndex(Index);
if (!h || h==INVALID_HANDLE_VALUE)
return FALSE;
HIDD_ATTRIBUTES Attributes;
if (!HidD_GetAttributes(h, &Attributes))
{
CloseHandle(h);
return FALSE;
};
*version = Attributes.VersionNumber;
CloseHandle(h);
return TRUE;
}
Now, Attributes is not a pointer, it is a struct.
I did try to initialize it but this does not help.
Any idea?
Tx
The first member of HIDD_ATTRIBUTES is size , that needs to be set to
sizeof(HIDD_ATTRIBUTES) before its used in any calls, Windows uses it to
figure out the version you are using.
Related
I understand eval string-to-function is impossible to use on the browsers' application programming interfaces, but there must be another strategy to use third party dependencies without node.js on v8 engine, given Cloudflare does it in-house, unless they disable the exclusive method by necessity or otherwise on their edge servers for Workers. I imagine I could gather the AST of the commonjs module, as I was able to by rollup watch, but what might the actual steps be, by tooling? I mention AMD for it seems to rely on string-to-function (to-which I've notice Mozilla MDN says nothing much about it).
I have been exploring the require.js repositories, and they either use eval or AST
function DEFNODE(type, props, methods, base) {
if (arguments.length < 4) base = AST_Node;
if (!props) props = [];
else props = props.split(/\s+/);
var self_props = props;
if (base && base.PROPS) props = props.concat(base.PROPS);
var code = "return function AST_" + type + "(props){ if (props) { ";
for (var i = props.length; --i >= 0; ) {
code += "this." + props[i] + " = props." + props[i] + ";";
}
var proto = base && new base();
if ((proto && proto.initialize) || (methods && methods.initialize))
code += "this.initialize();";
code += "}}";
//constructor
var cnstor = new Function(code)();
if (proto) {
cnstor.prototype = proto;
cnstor.BASE = base;
}
if (base) base.SUBCLASSES.push(cnstor);
cnstor.prototype.CTOR = cnstor;
cnstor.PROPS = props || null;
cnstor.SELF_PROPS = self_props;
cnstor.SUBCLASSES = [];
if (type) {
cnstor.prototype.TYPE = cnstor.TYPE = type;
}
if (methods)
for (i in methods)
if (HOP(methods, i)) {
if (/^\$/.test(i)) {
cnstor[i.substr(1)] = methods[i];
} else {
cnstor.prototype[i] = methods[i];
}
}
//a function that returns an object with [name]:method
cnstor.DEFMETHOD = function (name, method) {
this.prototype[name] = method;
};
if (typeof exports !== "undefined") exports[`AST_${type}`] = cnstor;
return cnstor;
}
var AST_Token = DEFNODE(
"Token",
"type value line col pos endline endcol endpos nlb comments_before file raw",
{},
null
);
https://codesandbox.io/s/infallible-darwin-8jcl2k?file=/src/mastercard-backbank/uglify/index.js
https://www.youtube.com/watch?v=EF7UW9HxOe4
Is it possible to make a C++ addon just to add a default object for
node.js named exports or am I Y’ing up the wrong X
'.so' shared library for C++ dlopen/LoadLibrary (or #include?)
“I have to say that I'm amazed that there is code out there that loads one native addon from another native addon! Is it done by acquiring and then calling an instance of the require() function, or perhaps by using uv_dlopen() directly?”
N-API: An api for embedding Node in applications
"[there is no ]napi_env[ just yet]."
node-api: allow retrieval of add-on file name - Missing module in Init
Andreas Rossberg - is AST parsing, or initialize node.js abstraction for native c++, enough?
v8::String::NewFromUtf8(isolate, "Index from C++!");
Rising Stack - Node Source
"a macro implicit" parameter - bridge object between
C++ and JavaScript runtimes
extract a function's parameters and set the return value.
#include <nan.h>
int build () {
NAN_METHOD(Index) {
info.GetReturnValue().Set(
Nan::New("Index from C++!").ToLocalChecked()
);
}
}
// Module initialization logic
NAN_MODULE_INIT(Initialize) {
/*Export the `Index` function
(equivalent to `export function Index (...)` in JS)*/
NAN_EXPORT(target, Index);
}
New module "App" Initialize function from NAN_MODULE_INIT (an atomic?-macro)
"__napi_something doesn't exist."
"node-addon-API module for C++ code (N-API's C code's headers)"
NODE_MODULE(App, Initialize);
Sep 17, 2013, 4:42:17 AM to v8-u...#googlegroups.com "This comes up
frequently, but the answer remains the same: scrap the idea. ;)
Neither the V8 parser nor its AST are designed for external
interfacing. In particular (1) V8's AST does not necessarily reflect
JavaScript syntax 1-to-1, (2) we change it all the time, and (3) it
depends on various V8 internals. And since all these points are
important for V8, don't expect the situation to change.
/Andreas"
V8 c++: How to import module via code to script context (5/28/22, edit)
"The export keyword may only be used in a module interface unit.
The keyword is attached to a declaration of an entity, and causes that
declaration (and sometimes the definition) to become visible to module
importers[ - except for] the export keyword in the module-declaration, which is just a re-use of the keyword (and does not actually “export” ...entities)."
SyntheticModule::virtual
ScriptCompiler::CompileModule() - "Corresponds to the ParseModule abstract operation in the ECMAScript specification."
Local<Function> foo_func = ...;//external
Local<Module> module = Module::CreateSyntheticModule(
isolate, name,
{String::NewFromUtf8(isolate, "foo")},
[](Local<Context> context, Local<Module> module) {
module->SetSyntheticModuleExport(
String::NewFromUtf8(isolate, "foo"), foo_func
);
});
Context-Aware addons from node.js' commonjs modules
export module index;
export class Index {
public:
const char* app() {
return "done!";
}
};
import index;
import <iostream>;
int main() {
std::cout << Index().app() << '\n';
}
node-addon-api (new)
native abstractions (old)
"Thanks to the crazy changes in V8 (and some in Node core), keeping native addons compiling happily across versions, particularly 0.10 to 0.12 to 4.0, is a minor nightmare. The goal of this project is to store all logic necessary to develop native Node.js addons without having to inspect NODE_MODULE_VERSION and get yourself into a macro-tangle[ macro = extern atomics?]."
Scope Isolate (v8::Isolate), variable Local (v8::Local)
typed_array_to_native.cc
"require is part of the Asynchronous Module Definition AMD API[, without "string-to-function" eval/new Function()],"
node.js makes objects, for it is written in C++.
"According to the algorithm, before finding
./node_modules/_/index.js, it tried looking for express in the
core Node.js modules. This didn’t exist, so it looked in node_modules,
and found a directory called _. (If there was a
./node_modules/_.js, it would load that directly.) It then
loaded ./node_modules/_/package.json, and looked for an exports
field, but this didn’t exist. It also looked for a main field, but
this didn’t exist either. It then fell back to index.js, which it
found. ...require() looks for node_modules in all of the parent directories of the caller."
But java?
I won't accept this answer until it works, but this looks promising:
https://developer.oracle.com/databases/nashorn-javascript-part1.html
If not to run a jar file or something, in the Worker:
https://github.com/nodyn/jvm-npm
require and build equivalent in maven, first, use "dist/index.js".
Specifically: [ScriptEngineManager][21]
https://stackoverflow.com/a/15787930/11711280
Actually: js.commonjs-require experimental
https://docs.oracle.com/en/graalvm/enterprise/21/docs/reference-manual/js/Modules/
Alternatively/favorably: commonjs builder in C (v8 and node.js)
https://www.reddit.com/r/java/comments/u7elf4/what_are_your_thoughts_on_java_isolates_on_graalvm/
Here I will explore v8/node.js src .h and .cc for this purpose
https://codesandbox.io/s/infallible-darwin-8jcl2k?file=/src/c.cpp
I'm curious why there is near machine-level C operability in Workers if not to use std::ifstream, and/or build-locally, without node.js require.
I need to change the block_timestamp to test timed voting.
Using VMContext, block_timestamp is changed using:
context.block_timestamp = get_timestamp();
testing_env!(context.clone());
How to do that in near_sdk_sim?
let (root, contract) = deploy_contract();
// Change the block_timestamp
Runtime has block_timestamp(), not sure how to use it.
// You should start with the master_account returned by init_simulator
// You can change the genesis config by giving
// near_sdk_sim::runtime::GenesisConfig to init_simulator instead of None
// FYI, the default value of block timestamp was 0 with None
let master_account = init_simulator(None);
// If you don't wrap this code block below in brackets
// or don't call it as a function from outside,
// you will encounter the error 'already borrowed: BorrowMutError'.
{
let mut runtime = master_account.borrow_runtime_mut();
// In near_sdk_sim, 1 block takes 1 second !
// So it changes the block timestamp 0 to 10000000000
runtime.produce_blocks(10u64);
}
EDIT:
I have heavily edited this question after making some significant new discoveries and the question not having any answers yet.
Historically/AFAIK, keeping your Mac awake while in closed-display mode and not meeting Apple's requirements, has only been possible with a kernel extension (kext), or a command run as root. Recently however, I have discovered that there must be another way. I could really use some help figuring out how to get this working for use in a (100% free, no IAP) sandboxed Mac App Store (MAS) compatible app.
I have confirmed that some other MAS apps are able to do this, and it looks like they might be writing YES to a key named clamshellSleepDisabled. Or perhaps there's some other trickery involved that causes the key value to be set to YES? I found the function in IOPMrootDomain.cpp:
void IOPMrootDomain::setDisableClamShellSleep( bool val )
{
if (gIOPMWorkLoop->inGate() == false) {
gIOPMWorkLoop->runAction(
OSMemberFunctionCast(IOWorkLoop::Action, this, &IOPMrootDomain::setDisableClamShellSleep),
(OSObject *)this,
(void *)val);
return;
}
else {
DLOG("setDisableClamShellSleep(%x)\n", (uint32_t) val);
if ( clamshellSleepDisabled != val )
{
clamshellSleepDisabled = val;
// If clamshellSleepDisabled is reset to 0, reevaluate if
// system need to go to sleep due to clamshell state
if ( !clamshellSleepDisabled && clamshellClosed)
handlePowerNotification(kLocalEvalClamshellCommand);
}
}
}
I'd like to give this a try and see if that's all it takes, but I don't really have any idea about how to go about calling this function. It's certainly not a part of the IOPMrootDomain documentation, and I can't seem to find any helpful example code for functions that are in the IOPMrootDomain documentation, such as setAggressiveness or setPMAssertionLevel. Here's some evidence of what's going on behind the scenes according to Console:
I've had a tiny bit of experience working with IOMProotDomain via adapting some of ControlPlane's source for another project, but I'm at a loss for how to get started on this. Any help would be greatly appreciated. Thank you!
EDIT:
With #pmdj's contribution/answer, this has been solved!
Full example project:
https://github.com/x74353/CDMManager
This ended up being surprisingly simple/straightforward:
1. Import header:
#import <IOKit/pwr_mgt/IOPMLib.h>
2. Add this function in your implementation file:
IOReturn RootDomain_SetDisableClamShellSleep (io_connect_t root_domain_connection, bool disable)
{
uint32_t num_outputs = 0;
uint32_t input_count = 1;
uint64_t input[input_count];
input[0] = (uint64_t) { disable ? 1 : 0 };
return IOConnectCallScalarMethod(root_domain_connection, kPMSetClamshellSleepState, input, input_count, NULL, &num_outputs);
}
3. Use the following to call the above function from somewhere else in your implementation:
io_connect_t connection = IO_OBJECT_NULL;
io_service_t pmRootDomain = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("IOPMrootDomain"));
IOServiceOpen (pmRootDomain, current_task(), 0, &connection);
// 'enable' is a bool you should assign a YES or NO value to prior to making this call
RootDomain_SetDisableClamShellSleep(connection, enable);
IOServiceClose(connection);
I have no personal experience with the PM root domain, but I do have extensive experience with IOKit, so here goes:
You want IOPMrootDomain::setDisableClamShellSleep() to be called.
A code search for sites calling setDisableClamShellSleep() quickly reveals a location in RootDomainUserClient::externalMethod(), in the file iokit/Kernel/RootDomainUserClient.cpp. This is certainly promising, as externalMethod() is what gets called in response to user space programs calling the IOConnectCall*() family of functions.
Let's dig in:
IOReturn RootDomainUserClient::externalMethod(
uint32_t selector,
IOExternalMethodArguments * arguments,
IOExternalMethodDispatch * dispatch __unused,
OSObject * target __unused,
void * reference __unused )
{
IOReturn ret = kIOReturnBadArgument;
switch (selector)
{
…
…
…
case kPMSetClamshellSleepState:
fOwner->setDisableClamShellSleep(arguments->scalarInput[0] ? true : false);
ret = kIOReturnSuccess;
break;
…
So, to invoke setDisableClamShellSleep() you'll need to:
Open a user client connection to IOPMrootDomain. This looks straightforward, because:
Upon inspection, IOPMrootDomain has an IOUserClientClass property of RootDomainUserClient, so IOServiceOpen() from user space will by default create an RootDomainUserClient instance.
IOPMrootDomain does not override the newUserClient member function, so there are no access controls there.
RootDomainUserClient::initWithTask() does not appear to place any restrictions (e.g. root user, code signing) on the connecting user space process.
So it should simply be a case of running this code in your program:
io_connect_t connection = IO_OBJECT_NULL;
IOReturn ret = IOServiceOpen(
root_domain_service,
current_task(),
0, // user client type, ignored
&connection);
Call the appropriate external method.
From the code excerpt earlier on, we know that the selector must be kPMSetClamshellSleepState.
arguments->scalarInput[0] being zero will call setDisableClamShellSleep(false), while a nonzero value will call setDisableClamShellSleep(true).
This amounts to:
IOReturn RootDomain_SetDisableClamShellSleep(io_connect_t root_domain_connection, bool disable)
{
uint32_t num_outputs = 0;
uint64_t inputs[] = { disable ? 1 : 0 };
return IOConnectCallScalarMethod(
root_domain_connection, kPMSetClamshellSleepState,
&inputs, 1, // 1 = length of array 'inputs'
NULL, &num_outputs);
}
When you're done with your io_connect_t handle, don't forget to IOServiceClose() it.
This should let you toggle clamshell sleep on or off. Note that there does not appear to be any provision for automatically resetting the value to its original state, so if your program crashes or exits without cleaning up after itself, whatever state was last set will remain. This might not be great from a user experience perspective, so perhaps try to defend against it somehow, for example in a crash handler.
I am using Windows 7 Professional and I am using SHFileOperation() to recursive copy one folder contents to another. But there is a locked file (opened exclusively by an application); I need to skip it, but SHFileOperation() returns 0x20 when tries to copy this file.
How can I skip this file during the file copy operation?
UPDATE: this is the code:
//
// CopyDirectory()
// рекурсивное копирование содержимого одной директории в другую средствами Windows
// lpszSource - исходная папка
// lpszDestination - папка назначения
//
BOOL CopyDirectory( LPSTR lpszSource, LPSTR lpszDestination )
{
LPSTR lpszNewSource = NULL;
// структура операции с файлами
SHFILEOPSTRUCT fileOP = { 0 };
// выделим память под новый путь
lpszNewSource = (LPSTR)calloc(strlen(lpszSource) + 50, 1);
// запишем новый путь с маской
wsprintf(lpszNewSource, "%s\\*", lpszSource);
// запишем параметры операции копирования
fileOP.wFunc = FO_COPY;
fileOP.pTo = lpszDestination;
fileOP.pFrom = lpszSource;
fileOP.fFlags = FOF_SILENT | FOF_NOCONFIRMMKDIR | FOF_NOCONFIRMATION | FOF_NOERRORUI | FOF_NO_UI;
// выполняем операцию
INT retVal = SHFileOperation( &fileOP );
// освободим память
FREE_NULL(lpszNewSource);
DebugPrint(DEBUG_INFO, "retVal = %d\n", retVal);
// возвращаем результат копирования
return retVal == 0;
}
The SHFileOperation() documentation says:
Return value
Type: int
Returns zero if successful; otherwise nonzero. Applications normally should simply check for zero or nonzero.
It is good practice to examine the value of the fAnyOperationsAborted member of the SHFILEOPSTRUCT. SHFileOperation can return 0 for success if the user cancels the operation. If you do not check fAnyOperationsAborted as well as the return value, you cannot know that the function accomplished the full task you asked of it and you might proceed under incorrect assumptions.
Do not use GetLastError with the return values of this function.
To examine the nonzero values for troubleshooting purposes, they largely map to those defined in Winerror.h. However, several of its possible return values are based on pre-Win32 error codes, which in some cases overlap the later Winerror.h values without matching their meaning. Those particular values are detailed here, and for these specific values only these meanings should be accepted over the Winerror.h codes.
In your case, 0x20 is not one of the pre-Win32 error codes, so it maps to a standard Win32 error code, specifically ERROR_SHARING_VIOLATION, which is appropriate for your situation as one of the files could not be accessed.
To skip the offending file, enable the FOF_NOERRORUI flag in the SHFILEOPSTRUCT::fFlags field. The SHFILEOPSTRUCT documentation says only the following about that flag:
FOF_NOERRORUI
Do not display a dialog to the user if an error occurs.
However, the documentation does also say this:
fAnyOperationsAborted
Type: BOOL
When the function returns, this member contains TRUE if any file operations were aborted before they were completed; otherwise, FALSE. An operation can be manually aborted by the user through UI or it can be silently aborted by the system if the FOF_NOERRORUI or FOF_NOCONFIRMATION flags were set.
The documentation for IFileOperation (which replaces SHFileOperation() on Vista and later) has more to say about the FOF_NOERRORUI flag:
FOF_NOERRORUI (0x0400)
Do not display a message to the user if an error occurs. If this flag is set without FOFX_EARLYFAILURE, any error is treated as if the user had chosen Ignore or Continue in a dialog box. It halts the current action, sets a flag to indicate that an action was aborted, and proceeds with the rest of the operation.
...
FOFX_EARLYFAILURE (0x00100000)
If FOFX_EARLYFAILURE is set together with FOF_NOERRORUI, the entire set of operations is stopped upon encountering any error in any operation. This flag is valid only when FOF_NOERRORUI is set.
So, with FOF_NOERRORUI enabled, the return value of ERROR_SHARING_VIOLATION, and also the SHFILEOPSTRUCT::fAnyOperationsAborted field being set to TRUE, will tell you that a file could not be accessed during the copy, but not which file specifically. It does not mean that the entire SHFileOperation() task failed completely.
I'm using Joomla 2.5 to build a medium-sized website, and I've decided to ease maintenance and content management headaches through creating menus automatically.
I've looked for extensions which did this, but only found Joomla 1.5 extensions. I ended up trying to upgrade a GPL extension called Auto Menu Magic.
It was easy to deal with the basic issues like the XML tags in the extension file, since there's a page in the Joomla which helps you migrate from Joomla 1.5 to 1.6.
The extension I mentioned has a function named onContentAfterSave which is called by joomla when an article is saved. I've been debugging through creating rubbish articles in the admin interface and changing the code to throw exceptions in several places, which I can see as error messages on the admin frontend.
This is where I got stuck:
$db = &JFactory::getDBO();
$menu = JTable::getInstance( 'menu');
$menu->menutype = $menutype;
$menu->name = $name;
$menu->link = $link;
$menu->type = $linktype;
$menu->published = $published;
$menu->componentid = $componentid;
$menu->parent = $menuparentid;
$menu->sublevel = $menusublevel;
$menu->checked_out = 0;
$menu->checked_out_time = 0;
$menu->pollid = 0;
$menu->browserNav = 0;
$menu->access = 0;
$menu->utaccess = 0;
$menu->lft = 0;
$menu->rgt = 0;
$menu->home = 0;
$menu->params = $params;
// Figure out the order (Just pop this article at the end of the list):
$menu->ordering = $menu->getNextOrder(
"menutype = ".$db->Quote($menu->menutype).
" AND published >= 0 AND parent = ".(int) $menu->parent
);
// Validate:
if (!$menu->check())
return NULL;
// DEBUG 2 -- Integrity check
throw new Exception ("menutype: $menutype, name: $name, link: $link published: $published, componentid: $componentid menuparentid: $menuparentid menusublevel: $menusublevel");
// Save:
if (!$menu->store())
return NULL;
// DEBUG 1
throw new Exception(" Could save! ");
As you can see above, I tried to throw an exception (DEBUG 1) when the menu was saved to the database. This exception was never reached, but the upper exception (DEBUG 2) is reached. This means that $menu->check() returns true, but not $menu->store(). I assume that the database is returning an error because some of the Joomla database structure might have changed after 1.5.
I have read the source a lot these past hours, but I can't find one thing. How can I look at the columns that a Joomla table uses, so I can debug this error properly?
Thanks in advance!
PS: I've looked at the SQL database too, but it doesn't help much. The variables seem to have different naming conventions from the column names.
I think it should look like this because I have been trying to convert auto menu as well!
$db = &JFactory::getDBO();
$menu = JTable::getInstance('menu');
$menu->menutype = $menutype;
$menu->title = $title;
$menu->alias = strtolower($title) ;
$menu->note = "Created by automenu";
$menu->path = $link;
$menu->link = $link;
$menu->type = $linktype;
$menu->published = $published;
$menu->parent_id = $menuparentid
$menu->level = $menusublevel;
$menu->componentid = $componentid;
$menu->ordering = 0;
$menu->checked_out = 0;
$menu->checked_out_time = 0;
$menu->browserNav = 0;
$menu->access = 1;
$menu->img = '';
$menu->templat_style_id = 0;
$menu->params = $params;
$menu->lft = 0;
$menu->rgt = 0;
$menu->home = 0;
$menu->language = '*';
$menu->client_id = 0;
I would be interseted to know if you ever got it working!
I'd suggest turning on Joomla debugging in the System Configuration. At the bottom of each page it shows all the queries it has executed, and this (depending on the plugin) might show you what SQL is being executed, and presumably, failing. There's likely to be a big list, so you may have to search through it a bit to find the statement you're interested in.
Fabio,
Many thanks! I will try it out and see if I can improve it further.
Mike
You're forgetting the first rule of Exceptions Club, if you throw something... you have to catch it.
I don't see a try/catch pair in your code so PHP would be stopping with a "Fatal Error..." for the uncaught exception so it would never get to the DEBUG 1. e.g.
Fatal error: Uncaught exception 'Exception' with message ...
Try wrapping your code in a try/catch pair and allowing the execution to continue after DEBUG 2 have a look at the PHP doc's for exceptions