I'm currently working on a project where I need to track the usage of several system calls and low-level functions like mmap, brk, sbrk. So far, I've been doing this using function interposition: I write a wrapper function with the same name as the function I'm replacing (mmap for example), and I load it in a program by setting the LD_P...
Hi all, I have an application a part of which uses shared libraries. These libraries are linked at compile time. At Runtime the loader expects the shared object to be in the LD_LIBRARY_PATH , if not found the entire application crashes with error "unable to load shared libraries".Note that there is no guarantee that client would be hav...
Hi all I have an application consisting of different modules written in C++. One of the modules is meant for handling distributed tasks on SunGrid Engine. It uses the DRMAA API for submitting and monitoring grid jobs.If the client doesn't supports grid, local machine should be used The shared object of the API libdrmaa.so is linked at c...
I'm writing an interposition library to track the usage of some library functions in libc, such as open(), close(), connect(), etc. It works generally well on most of the applications. However, when I try it with PHP, using PHP's MySQL module in particular, none of the function calls to libc inside this module is been tracked (so no conn...
Intro Let me apologise upfront for the long question. It is as short as I could make it, which is, unfortunately, not very short. Setup I have defined two interfaces, A and B: class A // An interface { public: virtual ~A() {} virtual void whatever_A()=0; }; class B // Another interface { public: virtual ~B() {} virtual voi...
Hi, I'm in the process of writing a kind of runtime system/interpreter, and one of things that I need to be able to do is call c/c++ functions located in external libraries. On linux I'm using the dlfcn.h functions to open a library, and call a function located within. The problem is that, when using dlsysm() the function pointer retur...
Hi ;-) I have build a little patch to append to a certain application and trace the invocations of some functions. Among them, malloc() and open(). I am using dlsym to store the pointer to the original symbol and replace the function name with my own. It compiles -and works- perfectly under linux. Here's the code: #define _GNU_SOURCE #...