1  /* print.c -- Print the current backtrace.
       2     Copyright (C) 2012-2023 Free Software Foundation, Inc.
       3     Written by Ian Lance Taylor, Google.
       4  
       5  Redistribution and use in source and binary forms, with or without
       6  modification, are permitted provided that the following conditions are
       7  met:
       8  
       9      (1) Redistributions of source code must retain the above copyright
      10      notice, this list of conditions and the following disclaimer.
      11  
      12      (2) Redistributions in binary form must reproduce the above copyright
      13      notice, this list of conditions and the following disclaimer in
      14      the documentation and/or other materials provided with the
      15      distribution.
      16  
      17      (3) The name of the author may not be used to
      18      endorse or promote products derived from this software without
      19      specific prior written permission.
      20  
      21  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
      22  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
      23  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      24  DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
      25  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      26  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
      27  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
      28  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
      29  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
      30  IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
      31  POSSIBILITY OF SUCH DAMAGE.  */
      32  
      33  #include "config.h"
      34  
      35  #include <stdio.h>
      36  #include <string.h>
      37  #include <sys/types.h>
      38  
      39  #include "backtrace.h"
      40  #include "internal.h"
      41  
      42  /* Passed to callbacks.  */
      43  
      44  struct print_data
      45  {
      46    struct backtrace_state *state;
      47    FILE *f;
      48  };
      49  
      50  /* Print one level of a backtrace.  */
      51  
      52  static int
      53  print_callback (void *data, uintptr_t pc, const char *filename, int lineno,
      54  		const char *function)
      55  {
      56    struct print_data *pdata = (struct print_data *) data;
      57  
      58    fprintf (pdata->f, "0x%lx %s\n\t%s:%d\n",
      59  	   (unsigned long) pc,
      60  	   function == NULL ? "???" : function,
      61  	   filename == NULL ? "???" : filename,
      62  	   lineno);
      63    return 0;
      64  }
      65  
      66  /* Print errors to stderr.  */
      67  
      68  static void
      69  error_callback (void *data, const char *msg, int errnum)
      70  {
      71    struct print_data *pdata = (struct print_data *) data;
      72  
      73    if (pdata->state->filename != NULL)
      74      fprintf (stderr, "%s: ", pdata->state->filename);
      75    fprintf (stderr, "libbacktrace: %s", msg);
      76    if (errnum > 0)
      77      fprintf (stderr, ": %s", strerror (errnum));
      78    fputc ('\n', stderr);
      79  }
      80  
      81  /* Print a backtrace.  */
      82  
      83  void __attribute__((noinline))
      84  backtrace_print (struct backtrace_state *state, int skip, FILE *f)
      85  {
      86    struct print_data data;
      87  
      88    data.state = state;
      89    data.f = f;
      90    backtrace_full (state, skip + 1, print_callback, error_callback,
      91  		  (void *) &data);
      92  }