glibc/sysdeps/generic/elf/backtracesymsfd.c

/* Write formatted list with names for addresses in backtrace to a file.
   Copyright (C) 1998, 2000, 2003 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <execinfo.h>
#include <string.h>
#include <sys/uio.h>

#include <stdio-common/_itoa.h>
#include <ldsodefs.h>

#if __ELF_NATIVE_CLASS == 32
# define WORD_WIDTH 8
#else
/* We assyme 64bits.  */
# define WORD_WIDTH 16
#endif


void
__backtrace_symbols_fd (array, size, fd)
     void *const *array;
     int size;
     int fd;
{
  struct iovec iov[9];
  int cnt;

  for (cnt = 0; cnt < size; ++cnt)
    {
      char buf[WORD_WIDTH];
      Dl_info info;
      size_t last = 0;

      if (_dl_addr (array[cnt], &info, NULL, NULL)
	  && info.dli_fname && info.dli_fname[0] != '\0')
	{
	  /* Name of the file.  */
	  iov[0].iov_base = (void *) info.dli_fname;
	  iov[0].iov_len = strlen (info.dli_fname);
	  last = 1;

	  /* Symbol name.  */
	  if (info.dli_sname != NULL)
	    {
	      char buf2[WORD_WIDTH];
	      size_t diff;

	      iov[1].iov_base = (void *) "(";
	      iov[1].iov_len = 1;
	      iov[2].iov_base = (void *) info.dli_sname;
	      iov[2].iov_len = strlen (info.dli_sname);

	      if (array[cnt] >= (void *) info.dli_saddr)
		{
		  iov[3].iov_base = (void *) "+0x";
		  diff = array[cnt] - info.dli_saddr;
		}
	      else
		{
		  iov[3].iov_base = (void *) "-0x";
		  diff = info.dli_saddr - array[cnt];
		}
	      iov[3].iov_len = 3;

	      iov[4].iov_base = _itoa_word ((unsigned long int) diff,
					    &buf2[WORD_WIDTH], 16, 0);
	      iov[4].iov_len = &buf2[WORD_WIDTH] - (char *) iov[4].iov_base;

	      iov[5].iov_base = (void *) ")";
	      iov[5].iov_len = 1;

	      last = 6;
	    }
	}

      iov[last].iov_base = (void *) "[0x";
      iov[last].iov_len = 3;
      ++last;

      iov[last].iov_base = _itoa_word ((unsigned long int) array[cnt],
				       &buf[WORD_WIDTH], 16, 0);
      iov[last].iov_len = &buf[WORD_WIDTH] - (char *) iov[last].iov_base;
      ++last;

      iov[last].iov_base = (void *) "]\n";
      iov[last].iov_len = 2;
      ++last;

      __writev (fd, iov, last);
    }
}
weak_alias (__backtrace_symbols_fd, backtrace_symbols_fd)