CODEWITHSUNDEEP
c++
Ravi Varshney
Ravi Varshney

Reputation: 61

How to Handle SIGSEGV and print back trace on receiving SIGSEGV in c/C++ program?

I m constructing a C++ program in which I need to handle SIGSEGV and Signal handler should be able to print the Back Trace. Can any one help in this.

Regards

Upvotes: 6

Views: 8775

Answers (3)

Jon Ander Ortiz Durántez
Jon Ander Ortiz Durántez

Reputation: 2592

The best way to get a SIGSEV backtrace is generating a core file more than printing a backtrace. Take care beacause if you handle SIGSEV the system will not call the default core generator.

If you want to handle the SIGSEV anyway (as have been commented before this is system deppendant), see the libc backtrace function [http://www.gnu.org/s/libc/manual/html_node/Backtraces.html ] , it could be useful.

Upvotes: 6

minghua
minghua

Reputation: 6593

Take a look at the sample code here:

C++ Code Snippet - Print Stack Backtrace Programmatically with Demangled Function Names.

You may need to demangle the symbols, that's what the code sample does.

And try two more options:

  • -fno-omit-frame-pointer
  • -rdynamic

The first option keeps frame pointer in generated code thus all the backtrace frames are accessible to the code. The 2nd keeps symbol information in the linked binary. That works on my arm9 build, and no -g is needed.

Upvotes: 1

rajeshnair
rajeshnair

Reputation: 1673

Adding to what Jon replied, you basically need a function like this to print backtrace. This function shoudl be called on the SIGSEGV. But I second Jon's point that letting the system generate corefile would be a much better debugging mechanism for you

void print_trace(int nSig)
{
  printf("print_trace: got signal %d\n", nSig);

  void           *array[32];    /* Array to store backtrace symbols */
  size_t          size;     /* To store the exact no of values stored */
  char          **strings;    /* To store functions from the backtrace list in ARRAY */
  size_t          nCnt;

  size = backtrace(array, 32);

  strings = backtrace_symbols(array, size);

  /* prints each string of function names of trace*/
  for (nCnt = 0; nCnt < size; nCnt++)
    fprintf(stderr, "%s\n", strings[nCnt]);


  exit(-1);
}

Upvotes: 2

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