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  • How to compile a C++ source code written for Linux/Unix on Windows Vista (code given)

    - by HTMZ
    I have a c++ source code that was written in linux/unix environment by some other author. It gives me errors when i compile it in windows vista environment. I am using Bloodshed Dev C++ v 4.9. please help. #include <iostream.h> #include <map> #include <vector> #include <string> #include <string.h> #include <strstream> #include <unistd.h> #include <stdlib.h> using namespace std; template <class T> class PrefixSpan { private: vector < vector <T> > transaction; vector < pair <T, unsigned int> > pattern; unsigned int minsup; unsigned int minpat; unsigned int maxpat; bool all; bool where; string delimiter; bool verbose; ostream *os; void report (vector <pair <unsigned int, int> > &projected) { if (minpat > pattern.size()) return; // print where & pattern if (where) { *os << "<pattern>" << endl; // what: if (all) { *os << "<freq>" << pattern[pattern.size()-1].second << "</freq>" << endl; *os << "<what>"; for (unsigned int i = 0; i < pattern.size(); i++) *os << (i ? " " : "") << pattern[i].first; } else { *os << "<what>"; for (unsigned int i = 0; i < pattern.size(); i++) *os << (i ? " " : "") << pattern[i].first << delimiter << pattern[i].second; } *os << "</what>" << endl; // where *os << "<where>"; for (unsigned int i = 0; i < projected.size(); i++) *os << (i ? " " : "") << projected[i].first; *os << "</where>" << endl; *os << "</pattern>" << endl; } else { // print found pattern only if (all) { *os << pattern[pattern.size()-1].second; for (unsigned int i = 0; i < pattern.size(); i++) *os << " " << pattern[i].first; } else { for (unsigned int i = 0; i < pattern.size(); i++) *os << (i ? " " : "") << pattern[i].first << delimiter << pattern[i].second; } *os << endl; } } void project (vector <pair <unsigned int, int> > &projected) { if (all) report(projected); map <T, vector <pair <unsigned int, int> > > counter; for (unsigned int i = 0; i < projected.size(); i++) { int pos = projected[i].second; unsigned int id = projected[i].first; unsigned int size = transaction[id].size(); map <T, int> tmp; for (unsigned int j = pos + 1; j < size; j++) { T item = transaction[id][j]; if (tmp.find (item) == tmp.end()) tmp[item] = j ; } for (map <T, int>::iterator k = tmp.begin(); k != tmp.end(); ++k) counter[k->first].push_back (make_pair <unsigned int, int> (id, k->second)); } for (map <T, vector <pair <unsigned int, int> > >::iterator l = counter.begin (); l != counter.end (); ) { if (l->second.size() < minsup) { map <T, vector <pair <unsigned int, int> > >::iterator tmp = l; tmp = l; ++tmp; counter.erase (l); l = tmp; } else { ++l; } } if (! all && counter.size () == 0) { report (projected); return; } for (map <T, vector <pair <unsigned int, int> > >::iterator l = counter.begin (); l != counter.end(); ++l) { if (pattern.size () < maxpat) { pattern.push_back (make_pair <T, unsigned int> (l->first, l->second.size())); project (l->second); pattern.erase (pattern.end()); } } } public: PrefixSpan (unsigned int _minsup = 1, unsigned int _minpat = 1, unsigned int _maxpat = 0xffffffff, bool _all = false, bool _where = false, string _delimiter = "/", bool _verbose = false): minsup(_minsup), minpat (_minpat), maxpat (_maxpat), all(_all), where(_where), delimiter (_delimiter), verbose (_verbose) {}; ~PrefixSpan () {}; istream& read (istream &is) { string line; vector <T> tmp; T item; while (getline (is, line)) { tmp.clear (); istrstream istrs ((char *)line.c_str()); while (istrs >> item) tmp.push_back (item); transaction.push_back (tmp); } return is; } ostream& run (ostream &_os) { os = &_os; if (verbose) *os << transaction.size() << endl; vector <pair <unsigned int, int> > root; for (unsigned int i = 0; i < transaction.size(); i++) root.push_back (make_pair (i, -1)); project (root); return *os; } void clear () { transaction.clear (); pattern.clear (); } }; int main (int argc, char **argv) { extern char *optarg; unsigned int minsup = 1; unsigned int minpat = 1; unsigned int maxpat = 0xffffffff; bool all = false; bool where = false; string delimiter = "/"; bool verbose = false; string type = "string"; int opt; while ((opt = getopt(argc, argv, "awvt:M:m:L:d:")) != -1) { switch(opt) { case 'a': all = true; break; case 'w': where = true; break; case 'v': verbose = true; break; case 'm': minsup = atoi (optarg); break; case 'M': minpat = atoi (optarg); break; case 'L': maxpat = atoi (optarg); break; case 't': type = string (optarg); break; case 'd': delimiter = string (optarg); break; default: cout << "Usage: " << argv[0] << " [-m minsup] [-M minpat] [-L maxpat] [-a] [-w] [-v] [-t type] [-d delimiter] < data .." << endl; return -1; } } if (type == "int") { PrefixSpan<unsigned int> prefixspan (minsup, minpat, maxpat, all, where, delimiter, verbose); prefixspan.read (cin); prefixspan.run (cout); }else if (type == "short") { PrefixSpan<unsigned short> prefixspan (minsup, minpat, maxpat, all, where, delimiter, verbose); prefixspan.read (cin); prefixspan.run (cout); } else if (type == "char") { PrefixSpan<unsigned char> prefixspan (minsup, minpat, maxpat, all, where, delimiter, verbose); prefixspan.read (cin); prefixspan.run (cout); } else if (type == "string") { PrefixSpan<string> prefixspan (minsup, minpat, maxpat, all, where, delimiter, verbose); prefixspan.read (cin); prefixspan.run (cout); } else { cerr << "Unknown Item Type: " << type << " : choose from [string|int|short|char]" << endl; return -1; } return 0; }

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  • Find vertices of a convex hull

    - by Jeff Bullard
    I am attempting to do this within CGAL. From a 3D point cloud, find the convex hull, then loop over the finite facets of the convex hull and print each facet's vertices. It seems like there should be a straightforward way to do this; I would have expected that 3D polyhedra would own a vector of facet objects, each of which in turn would own a vector of its edges, each of which in turn would own a vector of its vertices, and that their would be some access through this hierarchy using iterators. But so far I have been unable to find a simple way to navigate through this hierarchy (if it exists).

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  • How can I generate a view or projection matrix for OpenGL 3.+

    - by Ken
    I'm transitioning from OpenGL 2 to OpenGL 3.+ and to GLSL 1.5. I'm trying to avoid using the deprecated features. My question how do we now generate the view or projection matrix. I was using the matrix stack to calculate the projection matrix for me; GLfloat ptr[16]; gluPerspective(...); glGetFloatv(GL_MODELVIEW_MATRIX, ptr); //then pass ptr via a uniform to the shader But obviously the matrix stack is deprecated. So this approach is not the best an option going forward. I have the 'Red Book', 7th ed, which covers 3.0 & 3.1 and it still uses the deprecated matrix functions in it's examples. I could write some utility-code myself to generate the matrices. But I don't want to re-invent this particular wheel, especially when this functionality is required for every 3D graphics program. What is the accepted way to generate world,view & projection matrices for OpenGL? Is there an emerging 'standard' library for this? Or is there some other hidden (to me) functionality in OpenGL/GLSL which I have overlooked?

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  • Does RDNS for mail server have to match the mail server hostname exactly?

    - by threecheeseopera
    Typically when setting up a mail server, I create an rDNS record for the mail server IP to match the mail server hostname (ex: mail.example.com). Can I instead set the rDNS ptr to match the parent domain (e.g. example.com), if this server is being used for multiple purposes, and still send mail successfully (i.e. not be classified as spam b/c of mismatched rDNS)? Thanks! EDIT: The article at http://en.wikipedia.org/wiki/Forward_Confirmed_reverse_DNS seems to indicate that it might be more complicated than I had thought. For instance, 1) I did not know that you could have multiple PTR records for a given IP; 2) it appears that as long as each PTR record matches an A record, everything is good (basically nullifying my question). Would you agree?

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  • What's the most efficient way to find barycentric coordinates?

    - by bobobobo
    In my profiler, finding barycentric coordinates is apparently somewhat of a bottleneck. I am looking to make it more efficient. It follows the method in shirley, where you compute the area of the triangles formed by embedding the point P inside the triangle. Code: Vector Triangle::getBarycentricCoordinatesAt( const Vector & P ) const { Vector bary ; // The area of a triangle is real areaABC = DOT( normal, CROSS( (b - a), (c - a) ) ) ; real areaPBC = DOT( normal, CROSS( (b - P), (c - P) ) ) ; real areaPCA = DOT( normal, CROSS( (c - P), (a - P) ) ) ; bary.x = areaPBC / areaABC ; // alpha bary.y = areaPCA / areaABC ; // beta bary.z = 1.0f - bary.x - bary.y ; // gamma return bary ; } This method works, but I'm looking for a more efficient one!

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  • Run script when POST data is sent to Apache

    - by Nathan Adams
    Among my several years of running servers there seems to be a pattern with most spam activity. My question/idea is that is there a way to tell Apache to run a script when POST data is detected? What I would want to do is perform a reverse DNS lookup on the client's IP address, and then perform a DNS lookup on the hostname in the PTR record. Afterwards, perform some checks, excuse the pseudo-code: if PTR does not exist: deny POST request if IP of PTR hostname = client's IP Allow POST request else deny POST request Though I don't care about GET requests, even though they can be just as malicious, this idea is targeted towards spam comments which use POST data to send the comment data to the web server. In order to make sure there isn't much of a time delay, I would run my own recursive DNS server. Please do note, this isn't meant to be a sliver bullet to spam, but it should decrease the volume. Possible or impossible?

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  • Confusion about Rotation matrices from Euler Angles

    - by xEnOn
    I am trying to learn more about Euler Angles so as to help myself in understanding how I can control my camera better in the game. I came across the following formula that converts Euler Angles to rotation matrices: In the equation, I could see that the first matrix from the left is the rotation matrix about x-axis, the second is about y-axis and the third is about z-axis. From my understanding about ordinary matrix transformations, the later transformation is always applied to the right hand side. And if I'm right about this, then the above equation should have a rotation order starting from rotating about z-axis, y-axis, then finally x-axis. But, from the symbols it seems that the rotation order start rotating about x-axis, then y-axis, then finally z-axis. What should the actual order of the rotation be? Also, I am confuse about if the input vector, in this case, would be a row vector on the left, or a column vector on the right?

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  • How access PhysicalMaterial from Actor Class?

    - by EmAdpres
    I use Projectile for my weapon system and UDKProjectile has two main function to handle Hit of projectiles(=bullet of my weapon): simulated function ProcessTouch(Actor Other, Vector HitLocation, Vector HitNormal) // For Actors simulated event HitWall(vector HitNormal, actor Wall, PrimitiveComponent WallComp) // Everything except Actors ( I guess) the first method, the function just give me the actor which I hit and my question is How I can get that actor's physical material by first parameter ( Other ), in order to make a proper react about it ( for example a proper Sound of collide ) ... A tricky (but hateful ) way which I knew works is, make a Trace from a little back of that actor to that actor, and use HitInfo parameter which include physical Material ! But there should be a more standard way !

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  • Several classes need to access the same data, where should the data be declared?

    - by Juicy
    I have a basic 2D tower defense game in C++. Each map is a separate class which inherits from GameState. The map delegates the logic and drawing code to each object in the game and sets data such as the map path. In pseudo-code the logic section might look something like this: update(): for each creep in creeps: creep.update() for each tower in towers: tower.update() for each missile in missiles: missile.update() The objects (creeps, towers and missiles) are stored in vector-of-pointers. The towers must have access to the vector-of-creeps and the vector-of-missiles to create new missiles and identify targets. The question is: where do I declare the vectors? Should they be members of the Map class, and passed as arguments to the tower.update() function? Or declared globally? Or are there other solutions I'm missing entirely?

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  • box2d and constant movement

    - by Arnas
    i'm developing a game with a top down view, the players body is a circle. To move the character you need to tap on the screen and it moves to the spot. To achieve this i'm saving the coordinate of the touch and call a method every frame which applies linear velocity to the body with a vector of the direction the body should go _body->SetLinearVelocity(b2Vec2((a.x - currPos.x)/SPEED_RATIO,(size.height - a.y - currPos.y)/SPEED_RATIO)); //click position - current position, screen height - click position (since the y axis is flipped, (0,0) is in the bottom left ) - current position = vector of the direction we want to go now the problem with this is that the body slows down until it finally stops when getting closer to the point we want it to go, since the closer we are to that point the lenght of the vector gets smaller. Besides that i've read that it's bad practice to set linear velocity in box2d and i should use apply force instead, but that way the forces would add up and overshoot the target where it's supposed to stop. So what i'm asking is how to move a box2d body to a coordinate in constant speed.

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  • Elastic Collision Formula in Java

    - by Shijima
    I'm trying to write a Java formula based on this tutorial: 2-D elastic collisions without Trigonometry. I am in the section "Elastic Collisions in 2 Dimensions". In step 1, it mentions "Next, find the unit vector of n, which we will call un. This is done by dividing by the magnitude of n". My below code represents the normal vector of 2 objects (I'm using a simple array to represent the normal vector), but I am not really sure what the tutorial means by dividing the magnitude of n to get the un. int[] normal = new int[2]; normal[0] = ball2.x - ball1.x; normal[1] = ball2.y - ball1.y; Can anyone please explain what un is, and how I can calculate it with my array in Java?

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  • What does the Sys_PageIn() function do in Quake?

    - by Philip
    I've noticed in the initialization process of the original Quake the following function is called. volatile int sys_checksum; // **lots of code** void Sys_PageIn(void *ptr, int size) { byte *x; int j,m,n; //touch all memory to make sure its there. The 16-page skip is to //keep Win 95 from thinking we're trying to page ourselves in (we are //doing that, of course, but there's no reason we shouldn't) x = (byte *)ptr; for (n=0 ; n<4 ; n++) { for (m=0; m<(size - 16 * 0x1000) ; m += 4) { sys_checksum += *(int *)&x[m]; sys_checksum += *(int *)&x[m + 16 * 0x10000]; } } } I think I'm just not familiar enough with paging to understand this function. the void* ptr passed to the function is a recently malloc()'d piece of memory that is size bytes big. This is the whole function - j is an unreferenced variable. My best guess is that the volatile int sys_checksum is forcing the system to physically read all of the space that was just malloc()'d, perhaps to ensure that these spaces exist in virtual memory? Is this right? And why would someone do this? Is it for some antiquated Win95 reason?

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  • gem install of mongrel

    - by atlantis
    I initiated myself into rails development yesterday. I installed ruby 1.9.1 , rubygems and rails. Running 'gem install mongrel' worked fine and ostensibly installed mongrel too. I am slightly puzzled because script/server starts webrick by default 'which mongrel' returns nothing 'locate mongrel' returns lots of entries like . /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1 /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel . . . /usr/local/bin/mongrel_rails /usr/local/lib/ruby/gems/1.9.1/cache/mongrel-1.1.5.gem /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/evented_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/swiftiplied_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/evented_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/swiftiplied_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/mongrel-1.1.5 . . . Does look like I have mongrel installed (both the default installation and my custom install). So why doesn't which mongrel return something. Also trying to reinstall mongrel using 'gem install mongrel' returns throws its own set of exceptions : Building native extensions. This could take a while... ERROR: Error installing mongrel: ERROR: Failed to build gem native extension. /usr/local/bin/ruby extconf.rb install mongrel checking for main() in -lc... yes creating Makefile make gcc -I. -I/usr/local/include/ruby-1.9.1/i386-darwin9.7.0 -I/usr/local/include/ruby-1.9.1/ruby/backward -I/usr/local/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -D_XOPEN_SOURCE=1 -O2 -g -Wall -Wno-parentheses -fno-common -pipe -fno-common -o http11.o -c http11.c http11.c: In function 'http_field': http11.c:77: error: 'struct RString' has no member named 'ptr' http11.c:77: error: 'struct RString' has no member named 'len' http11.c:77: warning: left-hand operand of comma expression has no effect http11.c:77: warning: statement with no effect http11.c: In function 'header_done': http11.c:172: error: 'struct RString' has no member named 'ptr' http11.c:174: error: 'struct RString' has no member named 'ptr' http11.c:176: error: 'struct RString' has no member named 'ptr' http11.c:177: error: 'struct RString' has no member named 'len' http11.c: In function 'HttpParser_execute': http11.c:298: error: 'struct RString' has no member named 'ptr' http11.c:299: error: 'struct RString' has no member named 'len' make: *** [http11.o] Error 1

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  • `gem install mongrel` fails with ruby 1.9.1

    - by atlantis
    I initiated myself into rails development yesterday. I installed ruby 1.9.1, rubygems and rails. Running gem install mongrel worked fine and ostensibly installed mongrel too. I am slightly puzzled because: script/server starts webrick by default which mongrel returns nothing locate mongrel returns lots of entries like /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1 /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib /Developer/SDKs/MacOSX10.5.sdk/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel . . . /usr/local/bin/mongrel_rails /usr/local/lib/ruby/gems/1.9.1/cache/mongrel-1.1.5.gem /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/evented_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/doc/actionpack-2.3.2/rdoc/files/lib/action_controller/vendor/rack-1_0/rack/handler/swiftiplied_mongrel_rb.html /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/evented_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/actionpack-2.3.2/lib/action_controller/vendor/rack-1.0/rack/handler/swiftiplied_mongrel.rb /usr/local/lib/ruby/gems/1.9.1/gems/mongrel-1.1.5 . . . Does look like I have mongrel installed (both the default installation and my custom install). So why doesn't which mongrel return something. Also trying to reinstall mongrel using gem install mongrel returns throws its own set of exceptions: Building native extensions. This could take a while... ERROR: Error installing mongrel: ERROR: Failed to build gem native extension. /usr/local/bin/ruby extconf.rb install mongrel checking for main() in -lc... yes creating Makefile make gcc -I. -I/usr/local/include/ruby-1.9.1/i386-darwin9.7.0 -I/usr/local/include/ruby-1.9.1/ruby/backward -I/usr/local/include/ruby-1.9.1 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -D_XOPEN_SOURCE=1 -O2 -g -Wall -Wno-parentheses -fno-common -pipe -fno-common -o http11.o -c http11.c http11.c: In function 'http_field': http11.c:77: error: 'struct RString' has no member named 'ptr' http11.c:77: error: 'struct RString' has no member named 'len' http11.c:77: warning: left-hand operand of comma expression has no effect http11.c:77: warning: statement with no effect http11.c: In function 'header_done': http11.c:172: error: 'struct RString' has no member named 'ptr' http11.c:174: error: 'struct RString' has no member named 'ptr' http11.c:176: error: 'struct RString' has no member named 'ptr' http11.c:177: error: 'struct RString' has no member named 'len' http11.c: In function 'HttpParser_execute': http11.c:298: error: 'struct RString' has no member named 'ptr' http11.c:299: error: 'struct RString' has no member named 'len' make: *** [http11.o] Error 1

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  • wrapping boost::ublas with swig

    - by leon
    I am trying to pass data around the numpy and boost::ublas layers. I have written an ultra thin wrapper because swig cannot parse ublas' header correctly. The code is shown below #include <boost/numeric/ublas/vector.hpp> #include <boost/numeric/ublas/matrix.hpp> #include <boost/lexical_cast.hpp> #include <algorithm> #include <sstream> #include <string> using std::copy; using namespace boost; typedef boost::numeric::ublas::matrix<double> dm; typedef boost::numeric::ublas::vector<double> dv; class dvector : public dv{ public: dvector(const int rhs):dv(rhs){;}; dvector(); dvector(const int size, double* ptr):dv(size){ copy(ptr, ptr+sizeof(double)*size, &(dv::data()[0])); } ~dvector(){} }; with the SWIG interface that looks something like %apply(int DIM1, double* INPLACE_ARRAY1) {(const int size, double* ptr)} class dvector{ public: dvector(const int rhs); dvector(); dvector(const int size, double* ptr); %newobject toString; char* toString(); ~dvector(); }; I have compiled them successfully via gcc 4.3 and vc++9.0. However when I simply run a = dvector(array([1.,2.,3.])) it gives me a segfault. This is the first time I use swigh with numpy and not have fully understanding between the data conversion and memory buffer passing. Does anyone see something obvious I have missed? I have tried to trace through with a debugger but it crashed within the assmeblys of python.exe. I have no clue if this is a swig problem or of my simple wrapper. Anything is appreciated.

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  • How to obtain a pointer out of a C++ vtable?

    - by Josh Haberman
    Say you have a C++ class like: class Foo { public: virtual ~Foo() {} virtual DoSomething() = 0; }; The C++ compiler translates a call into a vtable lookup: Foo* foo; // Translated by C++ to: // foo->vtable->DoSomething(foo); foo->DoSomething(); Suppose I was writing a JIT compiler and I wanted to obtain the address of the DoSomething() function for a particular instance of class Foo, so I can generate code that jumps to it directly instead of doing a table lookup and an indirect branch. My questions are: Is there any standard C++ way to do this (I'm almost sure the answer is no, but wanted to ask for the sake of completeness). Is there any remotely compiler-independent way of doing this, like a library someone has implemented that provides an API for accessing a vtable? I'm open to completely hacks, if they will work. For example, if I created my own derived class and could determine the address of its DoSomething method, I could assume that the vtable is the first (hidden) member of Foo and search through its vtable until I find my pointer value. However, I don't know a way of getting this address: if I write &DerivedFoo::DoSomething I get a pointer-to-member, which is something totally different. Maybe I could turn the pointer-to-member into the vtable offset. When I compile the following: class Foo { public: virtual ~Foo() {} virtual void DoSomething() = 0; }; void foo(Foo *f, void (Foo::*member)()) { (f->*member)(); } On GCC/x86-64, I get this assembly output: Disassembly of section .text: 0000000000000000 <_Z3fooP3FooMS_FvvE>: 0: 40 f6 c6 01 test sil,0x1 4: 48 89 74 24 e8 mov QWORD PTR [rsp-0x18],rsi 9: 48 89 54 24 f0 mov QWORD PTR [rsp-0x10],rdx e: 74 10 je 20 <_Z3fooP3FooMS_FvvE+0x20> 10: 48 01 d7 add rdi,rdx 13: 48 8b 07 mov rax,QWORD PTR [rdi] 16: 48 8b 74 30 ff mov rsi,QWORD PTR [rax+rsi*1-0x1] 1b: ff e6 jmp rsi 1d: 0f 1f 00 nop DWORD PTR [rax] 20: 48 01 d7 add rdi,rdx 23: ff e6 jmp rsi I don't fully understand what's going on here, but if I could reverse-engineer this or use an ABI spec I could generate a fragment like the above for each separate platform, as a way of obtaining a pointer out of a vtable.

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  • Memory corruption in System.Move due to changed 8087CW mode (png + stretchblt)

    - by André Mussche
    I have strange a memory corruption problem. After many hours debugging and trying I think I found something. For example: I do a simple string assignment: sTest := 'SET LOCK_TIMEOUT '; However, the result sometimes becomes: sTest = 'SET LOCK'#0'TIMEOUT ' So, the _ gets replaced by an 0 byte. I have seen this happening once (reproducing is tricky, dependent on timing) in the System.Move function, when it uses the FPU stack (fild, fistp) for fast memory copy (in case of 9 till 32 bytes to move): ... @@SmallMove: {9..32 Byte Move} fild qword ptr [eax+ecx] {Load Last 8} fild qword ptr [eax] {Load First 8} cmp ecx, 8 jle @@Small16 fild qword ptr [eax+8] {Load Second 8} cmp ecx, 16 jle @@Small24 fild qword ptr [eax+16] {Load Third 8} fistp qword ptr [edx+16] {Save Third 8} ... Using the FPU view and 2 memory debug views (Delphi - View - Debug - CPU - Memory) I saw it going wrong... once... could not reproduce however... This morning I read something about the 8087CW mode, and yes, if this is changed into $27F I get memory corruption! Normally it is $133F: The difference between $133F and $027F is that $027F sets up the FPU for doing less precise calculations (limiting to Double in stead of Extended) and different infiniti handling (which was used for older FPU’s, but is not used any more). Okay, now I found why but not when! I changed the working of my AsmProfiler with a simple check (so all functions are checked at enter and leave): if Get8087CW = $27F then //normally $1372? if MainThreadID = GetCurrentThreadId then //only check mainthread DebugBreak; I "profiled" some units and dll's and bingo (see stack): Windows.StretchBlt(3372289943,0,0,514,345,4211154027,0,0,514,345,13369376) pngimage.TPNGObject.DrawPartialTrans(4211154027,(0, 0, 514, 345, (0, 0), (514, 345))) pngimage.TPNGObject.Draw($7FF62450,(0, 0, 514, 345, (0, 0), (514, 345))) Graphics.TCanvas.StretchDraw((0, 0, 514, 345, (0, 0), (514, 345)),$7FECF3D0) ExtCtrls.TImage.Paint Controls.TGraphicControl.WMPaint((15, 4211154027, 0, 0)) So it is happening in StretchBlt... What to do now? Is it a fault of Windows, or a bug in PNG (included in D2007)? Or is the System.Move function not failsafe?

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  • How to access a matrix in a matlab struct's field from a mex function?

    - by B. Ruschill
    I'm trying to figure out how to access a matrix that is stored in a field in a matlab structure from a mex function. That's awfully long winded... Let me explain: I have a matlab struct that was defined like the following: matrixStruct = struct('matrix', {4, 4, 4; 5, 5, 5; 6, 6 ,6}) I have a mex function in which I would like to be able to receive a pointer to the first element in the matrix (matrix[0][0], in c terms), but I've been unable to figure out how to do that. I have tried the following: /* Pointer to the first element in the matrix (supposedly)... */ double *ptr = mxGetPr(mxGetField(prhs[0], 0, "matrix"); /* Incrementing the pointer to access all values in the matrix */ for(i = 0; i < 3; i++){ printf("%f\n", *(ptr + (i * 3))); printf("%f\n", *(ptr + 1 + (i * 3))); printf("%f\n", *(ptr + 2 + (i * 3))); } What this ends up printing is the following: 4.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 I have also tried variations of the following, thinking that perhaps it was something wonky with nested function calls, but to no avail: /* Pointer to the first location of the mxArray */ mxArray *fieldValuePtr = mxGetField(prhs[0], 0, "matrix"); /* Get the double pointer to the first location in the matrix */ double *ptr = mxGetPr(fieldValuePtr); /* Same for loop code here as written above */ Does anyone have an idea as to how I can achieve what I'm trying to, or what I am potentially doing wrong? Thanks! Edit: As per yuk's comment, I tried doing similar operations on a struct that has a field called array which is a one-dimensional array of doubles. The struct containing the array is defined as follows: arrayStruct = struct('array', {4.44, 5.55, 6.66}) I tried the following on the arrayStruct from within the mex function: mptr = mxGetPr(mxGetField(prhs[0], 0, "array")); printf("%f\n", *(mptr)); printf("%f\n", *(mptr + 1)); printf("%f\n", *(mptr + 2)); ...but the output followed what was printed earlier: 4.440000 0.000000 0.000000

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  • Determining if Memory Pointer is Valid - C++

    - by Jim Fell
    It has been my observation that if free( ptr ) is called where ptr is not a valid pointer to system-allocated memory, an access violation occurs. Let's say that I call free like this: LPVOID ptr = (LPVOID)0x12345678; free( ptr ); This will most definitely cause an access violation. Is there a way to test that the memory location pointed to by ptr is valid system-allocated memory? It seems to me that the the memory management part of the Windows OS kernel must know what memory has been allocated and what memory remains for allocation. Otherwise, how could it know if enough memory remains to satisfy a given request? (rhetorical) That said, it seems reasonable to conclude that there must be a function (or set of functions) that would allow a user to determine if a pointer is valid system-allocated memory. Perhaps Microsoft has not made these functions public. If Microsoft has not provided such an API, I can only presume that it was for an intentional and specific reason. Would providing such a hook into the system prose a significant threat to system security? Situation Report Although knowing whether a memory pointer is valid could be useful in many scenarios, this is my particular situation: I am writing a driver for a new piece of hardware that is to replace an existing piece of hardware that connects to the PC via USB. My mandate is to write the new driver such that calls to the existing API for the current driver will continue to work in the PC applications in which it is used. Thus the only required changes to existing applications is to load the appropriate driver DLL(s) at startup. The problem here is that the existing driver uses a callback to send received serial messages to the application; a pointer to allocated memory containing the message is passed from the driver to the application via the callback. It is then the responsibility of the application to call another driver API to free the memory by passing back the same pointer from the application to the driver. In this scenario the second API has no way to determine if the application has actually passed back a pointer to valid memory.

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  • bind9 DNS Ubuntu names pingible on server, but not on Windows Machines?

    - by leeand00
    I setup a DNS server today on Ubuntu, following this tutorial. My intent was to setup my network for dns-name resolving on the private LAN within a single zone (nothing fancy I just want name resolution). I've tested the setup on the DNS server machine itself, and I can ping all the machines listed in the configuration file. I've also configured the Windows Machines on my network, and for some reason they are incapable of pinging by names as was possible on the DNS Server itself. I've tried running nslookup on the Windows DNS clients and I receive and error mentioning the address of the DNS server. DNS forwarding works fine, I'm not having any trouble accessing the internet, the problem only lies within accessing names within the private LAN. Here are my configuration files: options { directory "/var/cache/bind"; // If there is a firewall between you and nameservers you want // to talk to, you may need to fix the firewall to allow multiple // ports to talk. See http://www.kb.cert.org/vuls/id/800113 // If your ISP provided one or more IP addresses for stable // nameservers, you probably want to use them as forwarders. // Uncomment the following block, and insert the addresses replacing // the all-0's placeholder. // forwarders { // 0.0.0.0; // }; forwarders { 8.8.8.8; 8.8.8.4; 74.242.0.12; //68.87.76.178; }; auth-nxdomain no; # conform to RFC1035 listen-on-v6 { any; }; }; /etc/bind/named.conf.options zone "leerdomain.local" { type master; file "/etc/bind/zones/leerdomain.local.db"; notify no; }; zone "2.168.192.in-addr.arpa" { type master; file "/etc/bind/zones/rev.2.168.192.in-addr.arpa"; notify no; }; /etc/bind/named.conf.local Lookup: $TTL 3D @ IN SOA ns.leerdomain.local. admin.leerdomain.local. ( 2010011001 28800 3600 604800 38400 ); leerdomain.local. IN NS ns.leerdomain.local. ns IN A 192.168.2.9 asus IN A 192.168.2.254 www IN CNAME asus vaio IN A 192.168.2.253 iptouch IN A 192.168.2.252 toshiba IN A 192.168.2.251 gw IN A 192.168.2.1 TXT "Network Gateway" /etc/bind/zones/leerdomain.local.db (Validates fine with named-checkzone when validating zone leerdomain.local) Reverse Lookup: $TTL 3D @ IN SOA ns.leerdomain.local. admin.leerdomain.local. ( 201001101 28800 604800 604800 86400 ) IN NS ns.leerdomain.local. 1 IN PTR gw.leerdomain.local. 254 IN PTR asus.leerdomain.local. 253 IN PTR vaio.leerdomain.local. 252 IN PTR iptouch.leerdomain.local. 251 IN PTR toshiba.leerdomain.local. /etc/bind/zones/rev.2.168.192.in-addr.arpa *(Does not validate with named-checkzone when validating zone leerdomain.local gives an error of: zone leerdomain.local/IN: NS 'ns.leerdomain.local' has no address records (A or AAAA) zone leerdomain.local/IN: not loaded due to errors. * Despite not validating bind9 starts without errors in /var/log/syslog I've also configured a few of the windows machines on my network to have the static ip as specified in the lookup and reverse lookup config files. i.e. Using nslookup yields the following results: C:\Users\leeand00>nslookup ns Server: UnKnown Address: 192.168.2.9 *** UnKnown can't find ns: Non-existent domain C:\Users\leeand00>nslookup gw Server: UnKnown Address: 192.168.2.9 Name: gw. Additionally trying to ping by name also fails on machines that are not the DNS Server. Is there something wrong with my configuration of either the nameserver or the Windows Boxes that is keeping me from accessing other machines using names?

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  • How can I have multiple layers in my map array?

    - by Manl400
    How do I load Levels in my game, as in Layer 1 would be Objects, Layer 2 would be Characters and so on. I only need 3 layers, and they will all be put on top of each other. i.e having a flower with a transparent background to be put on grass or dirt on the layer below.I would like to Read From the same file too. How would i go about doing this? Any help would be appreciated. I load the map from a level file which are just numbers corresponding to a tile in the tilesheet. Here is the level file [Layer1] 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 [Layer2] 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 [Layer3] 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 And here is the code that interprets it void LoadMap(const char *filename, std::vector< std::vector <int> > &map) { std::ifstream openfile(filename); if(openfile.is_open()) { std::string line, value; int space; while(!openfile.eof()) { std::getline(openfile, line); if(line.find("[TileSet]") != std::string::npos) { state = TileSet; continue; } else if (line.find("[Layer1]") != std::string::npos) { state = Map; continue; } switch(state) { case TileSet: if(line.length() > 0) tileSet = al_load_bitmap(line.c_str()); break; case Map: std::stringstream str(line); std::vector<int> tempVector; while(!str.eof()) { std::getline(str, value, ' '); if(value.length() > 0) tempVector.push_back(atoi(value.c_str())); } map.push_back(tempVector); break; } } } else { } } and this is how it draws the map. Also the tile sheet is 1280 by 1280 and the tilesizeX and tilesizeY is 64 void DrawMap(std::vector <std::vector <int> > map) { int mapRowCount = map.size(); for(int i, j = 0; i < mapRowCount; i ++) { int mapColCount = map[i].size(); for (int j = 0; j < mapColCount; ++j) { int tilesetIndex = map[i][j]; int tilesetRow = floor(tilesetIndex / TILESET_COLCOUNT); int tilesetCol = tilesetIndex % TILESET_COLCOUNT; al_draw_bitmap_region(tileSet, tilesetCol * TileSizeX, tilesetRow * TileSizeY, TileSizeX, TileSizeY, j * TileSizeX, i * TileSizeX, NULL); } } } EDIT: http://i.imgur.com/Ygu0zRE.jpg

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  • OO Design - polymorphism - how to design for handing streams of different file types

    - by Kache4
    I've little experience with advanced OO practices, and I want to design this properly as an exercise. I'm thinking of implementing the following, and I'm asking if I'm going about this the right way. I have a class PImage that holds the raw data and some information I need for an image file. Its header is currently something like this: #include <boost/filesytem.hpp> #include <vector> namespace fs = boost::filesystem; class PImage { public: PImage(const fs::path& path, const unsigned char* buffer, int bufferLen); const vector<char> data() const { return data_; } const char* rawData() const { return &data_[0]; } /*** other assorted accessors ***/ private: fs::path path_; int width_; int height_; int filesize_; vector<char> data_; } I want to fill the width_ and height_ by looking through the file's header. The trivial/inelegant solution would be to have a lot of messy control flow that identifies the type of image file (.gif, .jpg, .png, etc) and then parse the header accordingly. Instead of using vector<char> data_, I was thinking of having PImage use a class, RawImageStream data_ that inherits from vector<char>. Each type of file I plan to support would then inherit from RawImageStream, e.g. RawGifStream, RawPngStream. Each RawXYZStream would encapsulate the respective header-parsing functions, and PImage would only have to do something like height_ = data_.getHeight();. Am I thinking this through correctly? How would I create the proper RawImageStream subclass for data_ to be in the PImage ctor? Is this where I could use an object factory? Anything I'm forgetting?

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  • rand() generating the same number – even with srand(time(NULL)) in my main!

    - by Nick Sweet
    So, I'm trying to create a random vector (think geometry, not an expandable array), and every time I call my random vector function I get the same x value, thought y and z are different. int main () { srand ( (unsigned)time(NULL)); Vector<double> a; a.randvec(); cout << a << endl; return 0; } using the function //random Vector template <class T> void Vector<T>::randvec() { const int min=-10, max=10; int randx, randy, randz; const int bucket_size = RAND_MAX/(max-min); do randx = (rand()/bucket_size)+min; while (randx <= min && randx >= max); x = randx; do randy = (rand()/bucket_size)+min; while (randy <= min && randy >= max); y = randy; do randz = (rand()/bucket_size)+min; while (randz <= min && randz >= max); z = randz; } For some reason, randx will consistently return 8, whereas the other numbers seem to be following the (pseudo) randomness perfectly. However, if I put the call to define, say, randy before randx, randy will always return 8. Why is my first random number always 8? Am I seeding incorrectly?

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  • Boost tuple + transform

    - by JH
    Is it possible to do the following. Say my boost tuple has <String, int> I would like to use std::transform + mem_fun to insert only the String element in a corresponding vector. Is it possible or are we required to use a loop and push_back(get<0) Ie the following doesn't like to compile... (unknown types...) result.resize(storage.size()) std::transform(storage.begin(), storage.end(), result.begin(), std::mem_fun(&boost::get<0>)); Here is an example (trying one of the comments): #include <boost/tuple/tuple.hpp> #include <vector> #include <string> #include <algorithm> int main(int argc, char**argv) { std::vector< boost::tuple<std::string, int> > storage; std::vector< std::string> result; result.resize(storage.size()); std::transform(storage.begin(), storage.end(), result.begin(), &boost::get<0, boost::tuple<std::string, int> >); return 0; } Output: g++ test.cpp /usr/include/boost/tuple/detail/tuple_basic.hpp: In instantiation of `boost::tuples::cons<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, TT>': /usr/include/boost/tuple/detail/tuple_basic.hpp:151: instantiated from `boost::tuples::element<0, boost::tuples::cons<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, TT> >' test.cpp:14: instantiated from here /usr/include/boost/tuple/detail/tuple_basic.hpp:329: error: `boost::tuples::cons<HT, TT>::tail' has incomplete type /usr/include/boost/tuple/detail/tuple_basic.hpp:329: error: invalid use of template type parameter test.cpp: In function `int main(int, char**)': test.cpp:14: error: no matching function for call to `transform(__gnu_cxx::__normal_iterator<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>*, std::vector<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, std::allocator<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type> > > >, __gnu_cxx::__normal_iterator<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>*, std::vector<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, std::allocator<boost::tuples::tuple<std::string, int, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type> > > >, __gnu_cxx::__normal_iterator<std::string*, std::vector<std::string, std::allocator<std::string> > >, <unresolved overloaded function type>)'

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  • C++ templates - matrix class

    - by lastOfMohicans
    Hi I'm learning templates in C++ so I decied to write matrix class which would be a template class. In Matrix.h file I wrote #pragma once #include "stdafx.h" #include <vector> using namespace std; template<class T> class Matrix { public: Matrix(); ~Matrix(); GetDataVector(); SetDataVector(vector<vector<T>> dataVector); bool operator == (Matrix* matrix); bool operator < (Matrix* matrix); bool operator <= (Matrix* matrix); bool operator > (Matrix* matrix); bool operator >= (Matrix* matrix); Matrix* operator + (Matrix* matrix); Matrix* operator - (Matrix* matrix); Matrix* operator * (Matrix* matrix); private: vector<vector<T>> datavector; int columns,rows; }; In Matrix cpp Visual Stuio automaticlly generated code for default constructors #include "StdAfx.h" #include "Matrix.h" Matrix::Matrix() { } Matrix::~Matrix() { } However if I want to compile this I get an error 'Matrix' : use of class template requires template argument list The error are in file Matrix.cpp in default constructors What may be the problem ??

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