I am trying to make a source code which I can check by Clang Static Analyzer.
I am fully newbie in Obj C so I don't know how can I use these small code parts.
Here is the checkers list:
http://clang-analyzer.llvm.org/available_checks.html#osx_checkers
osx.cocoa.AtSync (ObjC):
void test(id x) {
if (!x)
#synchronized(x) {} // warn: nil value used as mutex
}
I just need a 5-10 lines of code which I can test. I don't want to someone make codes for all checker, I just need an example for one.
Thanks!
Related
Logging VkResult enum values
The VkResult enum contains a lot of values. Unfortunately though, they are C enums which aliases an integer, so I cannot easily just log their names to the console. For this purpose, I am envisioning a function which does something like this:
void graphics::log_vk_result(VkResult result)
{
switch (result)
{
case VK_SUCCESS:
log_core_debug("VK_SUCCESS"); return;
case VK_NOT_READY:
log_core_debug("VK_NOT_READY"); return;
[...]
}
But some of the enum values are only supported by certain extensions, as indicated here. An example: The extension VK_EXT_debug_report introduces the following value to the enumeration: VK_ERROR_VALIDATION_FAILED_EXT. So my idea for (potentially) more portable code would be something like this:
void graphics::log_vk_result(VkResult result)
{
switch (result)
{
[...]
#if defined(VK_EXT_DEBUG_REPORT_EXTENSION_NAME)
case VK_ERROR_VALIDATION_FAILED_EXT:
log_core_debug("VK_ERROR_VALIDATION_FAILED_EXT");
#endif
}
I found this name by looking at the extension manual page. I cannot easily see whether or not VK_EXT_DEBUG_REPORT_EXTENSION_NAME is a macro or an enum - it is a const char* but stated under the section "New Enum Constants". So checking for this particular value, for this particular extension, was my default choice.
[I do realize this extension is marked as deprecated, and I'm not using it! I only use it as an example here.]
I have two questions:
Is this needed?
Is this the correct way of doing this?
Thanks a lot!
All of this is unnecessary, since Vulkan SDK already includes the desired functionality:
#include <vulkan/vk_enum_string_helper.h>
void graphics::log_vk_result( const VkResult result ){
log_core_debug( string_VkResult(result) );
}
I have this sonar error Major:
Found 'UR'-anomaly for variable 'language' (lines '83'-'85')
in this function:
public void saveAll(List<Language> languages){
//Found 'UR'-anomaly for variable 'country' (lines '83'-'85').
//Code Smell Major Open Not assigned 20min effort Comment
for (Language language: languages) {
save(language);
}
}
how to fix this major error please, thanks for advance
Edit:
Found even more information it this other SO post. While that is more PMD centric, the background information can be of interest to you.
Java for each loop being flagged as UR anomaly by PMD.
This is a rule from PMD it seems. Definition:
The dataflow analysis tracks local definitions, undefinitions and
references to variables on different paths on the data flow. From
those informations there can be found various problems. 1. UR -
Anomaly: There is a reference to a variable that was not defined
before. This is a bug and leads to an error. 2. DU - Anomaly: A
recently defined variable is undefined. These anomalies may appear in
normal source text. 3. DD - Anomaly: A recently defined variable is
redefined. This is ominous but don't have to be a bug.
There is an open bug report for this:
https://sourceforge.net/p/pmd/bugs/1190/
In the example they report it for Arrays, but somebody commented that it happens for them also for collections.
Example:
public static void main(final String[] args) {
for (final String string : args) {
string.getBytes(); //UR Anomaly
}
for (int i = 0; i < args.length; i++) {
args[i].getBytes();
}
}
In our sonar setup we don't use this rule. Based on the available information you may wish not to use it in yours.
I am using fenced code blocks in Doxygen using the markdown syntax. This makes it easy to add a simple code example, like this:
~~~~~{.cpp}
void doSomething()
{
}
~~~~~
When I try to add comments into the fenced code block using two forward slashes, Doxygen seems to remove the slashes. So when I write this:
~~~~~{.cpp}
void doSomething()
{
// This function should do something
}
~~~~~
I get this output:
void doSomething()
{
This function should do something
}
How can I tell Doxygen to keep the comments in the fenced code block?
EDIT:
The complete file looks like this (we use the standard Doxygen extension of .dox for documentation-only files):
/*!
\page PATTERN_SAMPLE Sample
~~~~~{.cpp}
void doSomething()
{
// This function should do something
}
~~~~~
*/
The result looks like this:
Try with \code
\code{.cpp}
class Cpp {};
\endcode
I encountered the same issue. No need to change code format. You can specify STRIP_CODE_COMMENTS as NO: this setting outputs the source code with the comment.
# Setting the STRIP_CODE_COMMENTS tag to YES will instruct doxygen to hide any
# special comment blocks from generated source code fragments. Normal, C++ and
# Fortran comments will always remain visible.
# The default value is: YES.
STRIP_CODE_COMMENTS = NO
I'm putting together a Mac OS X Application and I'm trying to register to receive Display Reconfiguration notices, but I'm very lost right now. I've been reading Apple's documentation and some forums posts, etc., but everything seems to assume a better knowledge of things than I apparently possess. I understand that I have to request the callback inside a run loop for it to work properly. I don't know how to set up a basic run loop for it, though. I also feel like the example Apple has in their documentation is missing stuff they are expecting me to already know. To display my ignorance here is what I feel like things should look like.
NSRunLoop *rLoop = [NSRunLoop currentRunLoop];
codeToStartRunLoop
void MyDisplayReconfigurationCallBack (
CGDirectDisplayID display,
CGDisplayChangeSummaryFlags flags,
void *userInfo);
{
if (flags & kCGDisplayAddFlag) {
NSLog (#"Display Added");
}
else if (kCGDisplayRemoveFlag) {
NSLog (#"Display Removed");
}
}
CGDisplayRegisterReconfigurationCallback(MyDisplayReconfigurationCallBack, NULL);
The actual code I got was from Apple's Example, but it tells me that flags is an undeclared identifier at this point and won't compile. Not that it would work right since I don't have it in a run loop. I was hoping to find a tutorial somewhere that explains registering for system callback in a run loop but have not been successful. If anyone could point me in the right direction I'd super appreciate it.
(I'm sure that you'll be able to tell from my question that I'm very green. I taught myself Objective-C out of a book as my first programming language. I skipped C, so every once in a while I hit a snag somewhere that I can't figure out.)
If you're writing a Mac OS X application, the AppKit has already set up a run loop for you, so you don't need to worry about that part. You really only need to create your own run loop in Cocoa when you are also creating your own thread.
For the "undeclared identifier" part, it looks like it's due to a typo/syntax mistake:
void MyDisplayReconfigurationCallBack (CGDirectDisplayID display,
CGDisplayChangeSummaryFlags flags,
void *userInfo);
// Semicolon makes this an invalid function definition^^
{
// This is an anonymous block,* and flags wasn't declared in it
if (flags & kCGDisplayAddFlag) {
// etc.
}
Also, unlike some other languages, you can't declare or define functions inside of other functions, methods, or blocks* -- they have to be at the top level of the file. You can't put this in the same place where you call CGDisplayRegisterReconfigurationCallback.
Just as an sample (I have no idea what the rest of your code really looks like):
// MyClassThatIsInterestedInDisplayConfiguration.m
#import "MyClassThatIsInterestedInDisplayConfiguration.h"
// Define callback function at top level of file
void MyDisplayReconfigurationCallBack (
CGDirectDisplayID display,
CGDisplayChangeSummaryFlags flags,
void *userInfo)
{
if (flags & kCGDisplayAddFlag) {
NSLog (#"Display Added");
}
else if (kCGDisplayRemoveFlag) {
NSLog (#"Display Removed");
}
}
#implementation MyClassThatIsInterestedInDisplayConfiguration
- (void) comeOnBabyAndDoTheRegistrationWithMe {
// Register callback function inside a method
CGDisplayRegisterReconfigurationCallback(MyDisplayReconfigurationCallBack,
NULL);
}
#end
*The basic C curly-brace-delimited thing, not the new cool Obj-C ad hoc function thing.
I have troubles with dynamic loading of libraries - my code panics with Kern-Exec 3. The code is as follows:
TFileName dllName = _L("mydll.dll");
TFileName dllPath = _L("c:\\sys\\bin\\");
RLibrary dll;
TInt res = dll.Load(dllName, dllPath); // Kern-Exec 3!
TLibraryFunction f = dll.Lookup(1);
if (f)
f();
I receive panic on TInt res = dll.Load(dllName, dllPath); What can I do to get rid of this panic? mydll.dll is really my dll, which has only 1 exported function (for test purposes). Maybe something wrong with the DLL? Here's what it is:
def file:
EXPORTS
_ZN4Init4InitEv # 1 NONAME
pkg file:
#{"mydll DLL"},(0xED3F400D),1,0,0
;Localised Vendor name
%{"Vendor-EN"}
;Unique Vendor name
:"Vendor"
"$(EPOCROOT)Epoc32\release\$(PLATFORM)\$(TARGET)\mydll.dll"-"!:\sys\bin\mydll.dll"
mmp file:
TARGET mydll.dll
TARGETTYPE dll
UID 0x1000008d 0xED3F400D
USERINCLUDE ..\inc
SYSTEMINCLUDE \epoc32\include
SOURCEPATH ..\src
SOURCE mydllDllMain.cpp
LIBRARY euser.lib
#ifdef ENABLE_ABIV2_MODE
DEBUGGABLE_UDEBONLY
#endif
EPOCALLOWDLLDATA
CAPABILITY CommDD LocalServices Location MultimediaDD NetworkControl NetworkServices PowerMgmt ProtServ ReadDeviceData ReadUserData SurroundingsDD SwEvent TrustedUI UserEnvironment WriteDeviceData WriteUserData
source code:
// Exported Functions
namespace Init
{
EXPORT_C TInt Init()
{
// no implementation required
return 0;
}
}
header file:
#ifndef __MYDLL_H__
#define __MYDLL_H__
// Include Files
namespace Init
{
IMPORT_C TInt Init();
}
#endif // __MYDLL_H__
I have no ideas about this... Any help is greatly appreciated.
P.S. I'm trying to do RLibrary::Load because I have troubles with static linkage. When I do static linkage, my main program doesn't start at all. I decided to check what happens and discovered this issue with RLibrary::Load.
A KERN-EXEC 3 panic is caused by an unhandled exception (CPU fault) generated by trying to invalidly access a region of memory. This invalid memory access can be for both code (for example, bad PC by stack corruption) or data (for example, accessing freed memory). As such these are typically observed when dereferencing a NULL pointer (it is equivalent to a segfault).
Certainly the call to RLibrary::Load should never raise a KERN-EXEC 3 due to programmatic error, it is likely to be an environmental issue. As such I have to speculate on what is happening.
I believe the issue that is observed is due to stack overflow. Your MMP file does not specify the stack or heap size the initial thread should use. As such the default of 4Kb (if I remember correctly) will be used. Equally you are using TFileName - use of these on the stack is generally not recommended to avoid... stack overflow.
You would be better off using the _LIT() macro instead - this will allow you to provide the RLibrary::Load function with a descriptor directly referencing the constant strings as located in the constant data section of the binary.
As a side note, you should check the error value to determine the success of the function call.
_LIT(KMyDllName, "mydll.dll");
_LIT(KMyDllPath, "c:\\sys\\bin\\");
RLibrary dll;
TInt res = dll.Load(KMyDllName, MyDllPath); // Hopefully no Kern-Exec 3!
if(err == KErrNone)
{
TLibraryFunction f = dll.Lookup(1);
if (f)
f();
}
// else handle error
The case that you can't use static linkage should be a strong warning to you. It shows that there is something wrong with your DLL and using dynamic linking won't change anything.
Usually in these cases the problem is in mismatched capabilities. DLL must have at least the same set of capabilities that your main program has. And all those capabilities should be covered by your developer cert.