A tool for tracking memory allocation based ld-preload

• how to build

  make
  cd example && make
  

• how to use

  a simple way is to execute something like below :

  LD_PRELOAD=/you_path/libmTrace.so /you_path/application

  such as:

  cd example && make
  LD_PRELOAD=../libmTrace.so ./example
  

  Run example generate trace log. You can see appliaction invoke malloc/free/new/delete backtrace.

  ... 
  
  malloc (247) returned @0x418590
  [backtrace]
  ../libmTrace.so(_Z14printBacktracev 0x2b) [0x7ffff7fd9370]
  ../libmTrace.so( 0x146c) [0x7ffff7fd946c]
  ./example(_Z7notleaki 0x31) [0x401287]
  ./example(main 0x7f) [0x401382]
  /lib64/libc.so.6(__libc_start_main 0xf3) [0x7ffff71066a3]
  ./example(_start 0x2e) [0x40110e]
  
  
  freed pointer @0x418590
  [backtrace]
  ../libmTrace.so(_Z14printBacktracev 0x2b) [0x7ffff7fd9370]
  ../libmTrace.so( 0x14d8) [0x7ffff7fd94d8]
  ./example(_Z7notleaki 0x58) [0x4012ae]
  ./example(main 0x7f) [0x401382]
  /lib64/libc.so.6(__libc_start_main 0xf3) [0x7ffff71066a3]
  ./example(_start 0x2e) [0x40110e]
  
  ...
  
  

• parse tools

  parse.sh can analyze the logs of memory allocation and memory release, and locate which memory has not been released after application.

  for example:

  // example.cpp 
  void leak(int num)
  {
      printf("%s [malloc] allocating %d bytes...\n", __PRETTY_FUNCTION__, num);
      void * p1 = malloc(num);
      memset(p1, 0, num);
  
      printf("%s [new] allocating %d bytes...\n", __PRETTY_FUNCTION__, num);
      char * p2 = new char[num];
      memset(p2, 0, num);
      return;
  }
  

  // parse tool locate leak memery
  maybe leak memery info :
  addr :  0x417a30
  info :  
      {
          'Addr': '0x417a30', 'type': 'alloc', 'size': 769, 
          'backtrace': '
              ../libmTrace.so(_Z14printBacktracev 0x1f) [0x7ffff7fd9327]
              ../libmTrace.so( 0x1418) [0x7ffff7fd9418]
              ./example(_Z4leaki 0x31) [0x4011f7]
              ./example(main 0x6e) [0x401371]
              /lib64/libc.so.6(__libc_start_main 0xf3) [0x7ffff71066a3]
              ./example(_start 0x2e) [0x40110e]'
      }
  

• read more

  https://www.jianshu.com/p/c2c6644a7380