blob: 737f29a479b0cc3b477c7b8fff772b812b1992c5 [file] [log] [blame]
/****************************************************************************
* *
* GNAT RUN-TIME COMPONENTS *
* *
* T R A C E B A C K - G C C t a b l e s *
* *
* C Implementation File *
* *
* Copyright (C) 2004-2012, Free Software Foundation, Inc. *
* *
* GNAT is free software; you can redistribute it and/or modify it under *
* terms of the GNU General Public License as published by the Free Soft- *
* ware Foundation; either version 3, or (at your option) any later ver- *
* sion. GNAT is distributed in the hope that it will be useful, but WITH- *
* OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
* or FITNESS FOR A PARTICULAR PURPOSE. *
* *
* As a special exception under Section 7 of GPL version 3, you are granted *
* additional permissions described in the GCC Runtime Library Exception, *
* version 3.1, as published by the Free Software Foundation. *
* *
* You should have received a copy of the GNU General Public License and *
* a copy of the GCC Runtime Library Exception along with this program; *
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see *
* <http://www.gnu.org/licenses/>. *
* *
* GNAT was originally developed by the GNAT team at New York University. *
* Extensive contributions were provided by Ada Core Technologies Inc. *
* *
****************************************************************************/
/* This is an implementation of the __gnat_backtrace routine using the
underlying GCC unwinding support associated with the exception handling
infrastructure. This will only work for ZCX based applications. */
#include <unwind.h>
/* The implementation boils down to a call to _Unwind_Backtrace with a
tailored callback and carried-on data structure to keep track of the
input parameters we got as well as of the basic processing state. */
/******************
* trace_callback *
******************/
#if !defined (__USING_SJLJ_EXCEPTIONS__)
typedef struct {
void ** traceback;
int max_len;
void * exclude_min;
void * exclude_max;
int n_frames_to_skip;
int n_frames_skipped;
int n_entries_filled;
} uw_data_t;
#if defined (__ia64__) && defined (__hpux__)
#include <uwx.h>
#endif
static _Unwind_Reason_Code
trace_callback (struct _Unwind_Context * uw_context, uw_data_t * uw_data)
{
char * pc;
#if defined (__ia64__) && defined (__hpux__) && defined (USE_LIBUNWIND_EXCEPTIONS)
/* Work around problem with _Unwind_GetIP on ia64 HP-UX. */
uwx_get_reg ((struct uwx_env *) uw_context, UWX_REG_IP, (uint64_t *) &pc);
#else
pc = (char *) _Unwind_GetIP (uw_context);
#endif
if (uw_data->n_frames_skipped < uw_data->n_frames_to_skip)
{
uw_data->n_frames_skipped ++;
return _URC_NO_REASON;
}
if (uw_data->n_entries_filled >= uw_data->max_len)
return _URC_NORMAL_STOP;
if (pc < (char *)uw_data->exclude_min || pc > (char *)uw_data->exclude_max)
uw_data->traceback [uw_data->n_entries_filled ++] = pc + PC_ADJUST;
return _URC_NO_REASON;
}
#endif
/********************
* __gnat_backtrace *
********************/
int
__gnat_backtrace (void ** traceback __attribute__((unused)),
int max_len __attribute__((unused)),
void * exclude_min __attribute__((unused)),
void * exclude_max __attribute__((unused)),
int skip_frames __attribute__((unused)))
{
#if defined (__USING_SJLJ_EXCEPTIONS__)
/* We have no unwind material (tables) at hand with sjlj eh, and no
way to retrieve complete and accurate call chain information from
the context stack we maintain. */
return 0;
#else
uw_data_t uw_data;
/* State carried over during the whole unwinding process. */
uw_data.traceback = traceback;
uw_data.max_len = max_len;
uw_data.exclude_min = exclude_min;
uw_data.exclude_max = exclude_max;
uw_data.n_frames_to_skip = skip_frames;
uw_data.n_frames_skipped = 0;
uw_data.n_entries_filled = 0;
_Unwind_Backtrace ((_Unwind_Trace_Fn)trace_callback, &uw_data);
return uw_data.n_entries_filled;
#endif
}