/*
 * $QNXLicenseC:
 * Copyright 2007,2008, QNX Software Systems. All Rights Reserved.
 *
 * You must obtain a written license from and pay applicable
 * license fees to QNX Software Systems before you may reproduce,
 * modify or distribute this software, or any work that includes
 * all or part of this software.   Free development licenses are
 * available for evaluation and non-commercial purposes.  For more
 * information visit http://licensing.qnx.com or email
 * licensing@qnx.com.
 *
 * This file may contain contributions from others.  Please review
 * this entire file for other proprietary rights or license notices,
 * as well as the QNX Development Suite License Guide at
 * http://licensing.qnx.com/license-guide/ for other information.
 * $
 */

#ifndef _GATHER_H_INCLUDED
#define _GATHER_H_INCLUDED

int
_BT(gather)(mem_reader_t *rdr, bt_addr_t fp,
			bt_addr_t *pc, int pc_ary_sz, int *count,
			bt_addr_t stack_limit, bt_addr_t last_pc);
#ifndef _BT_LIGHT
int
_bt_gather_other(bt_accessor_t *acc,
				 mem_reader_t *rdr,
				 bt_addr_t *pc, int pc_ary_sz, int *count);
#endif
int
_BT(find_prolog)(mem_reader_t *rdr,
				 bt_addr_t fp, bt_addr_t pc, bt_addr_t lowlimit,
				 bt_addr_t *caller_fp, bt_addr_t *caller_pc,
				 bt_addr_t *alternate_fp);

/*
 * Return address is 4 bytes passed the branch.
 */
#define BT_GATHER_ADJUST_PC 4
#define BT_GATHER_ADJUST_PC_TRAP 2

#define BT_GATHER_MAKE_LABEL() start_of_get_backtrace:

#define BT_GATHER_SELF(err,rdr,pc,pc_ary_sz,count,stack_limit)       \
	do { uint32_t fp;                                                \
	bt_addr_t caller_fp, caller_pc;                                  \
	bt_addr_t alternate_fp; /* don't care */                         \
	bt_addr_t my_pc;                                                 \
	int ret;                                                         \
	/* Get bt_get_backtrace's own frame pointer */                   \
	/* May not be accurate, but that's the best */                   \
	/* can be done */                                                \
	asm volatile("mov r14, %0" :"=r"(fp));                           \
	my_pc= (bt_addr_t)&&start_of_get_backtrace;                      \
	/* Do not include get_backtrace() in the backtrace ... */        \
	ret=_BT(find_prolog)(rdr, fp, my_pc,                             \
						 (bt_addr_t)BT(get_backtrace),               \
						 &caller_fp, &caller_pc,                     \
						 &alternate_fp);                             \
	if (ret == 1) {                                                  \
		if (stack_limit == 0 || caller_fp > stack_limit) {           \
			/* No need to check caller_fp against stack_limit,       \
	    	 * because from within bt_get_backtrace, it is           \
			 * certain that caller_fp < stack_limit */               \
			pc[0]=caller_pc;                                         \
			count=1;                                                 \
		}                                                            \
		if (_BT(gather)(rdr, caller_fp,                              \
					    pc, pc_ary_sz, &count,                       \
						stack_limit, caller_pc) == -1)               \
			err=errno;                                               \
	} else if (ret==-1)                                              \
		err=errno;                                                   \
	/* else can't backtrace, but that's ok... */                     \
	}while(0)


#endif

