erl_db_util.c

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#endif
#define FAIL_TERM am_EXIT /* The term to set as return when bif fails and
			     do_catch != 0 */

    *return_flags = 0U;

restart:
    ep = &term;
    esp = mpsp->heap + prog->stack_offset;
    sp = (Eterm **) esp;
    hp = mpsp->heap;
    ehp = mpsp->heap + prog->eheap_offset;
    ret = am_true;
    do_catch = 0;
    fail_label = -1;

    for (;;) {
#ifdef DMC_DEBUG
	if (*heap_fence != FENCE_PATTERN) {
	    erl_exit(1, "Heap fence overwritten in db_prog_match after op "
		     "0x%08x, overwritten with 0x%08x.", save_op, *heap_fence);
	}
	if (*eheap_fence != FENCE_PATTERN) {
	    erl_exit(1, "Eheap fence overwritten in db_prog_match after op "
		     "0x%08x, overwritten with 0x%08x.", save_op, 
		     *eheap_fence);
	}
	if (*stack_fence != FENCE_PATTERN) {
	    erl_exit(1, "Stack fence overwritten in db_prog_match after op "
		     "0x%08x, overwritten with 0x%08x.", save_op, 
		     *stack_fence);
	}
	save_op = *pc;
#endif
	switch (*pc++) {
	case matchTryMeElse:
	    n = *pc++;
	    fail_label = prog->labels[n];
	    break;
	case matchArray: /* only when DCOMP_TRACE, is always first
			    instruction. */
	    n = *pc++;
	    if ((int) n != arity)
		FAIL();
	    ep = (Eterm *) *ep;
	    break;
	case matchArrayBind: /* When the array size is unknown. */
	    n = *pc++;
	    hp[n] = dpm_array_to_list(psp, (Eterm *) term, arity);
	    break;
	case matchTuple: /* *ep is a tuple of arity n */
	    if (!is_tuple(*ep))
		FAIL();
	    ep = tuple_val(*ep);
	    n = *pc++;
	    if (arityval(*ep) != n)
		FAIL();
	    ++ep;
	    break;
	case matchPushT: /* *ep is a tuple of arity n, 
			    push ptr to first element */
	    if (!is_tuple(*ep))
		FAIL();
	    tp = tuple_val(*ep);
	    n = *pc++;
	    if (arityval(*tp) != n)
		FAIL();
	    *sp++ = tp + 1;
	    ++ep;
	    break;
	case matchList:
	    if (!is_list(*ep))
		FAIL();
	    ep = list_val(*ep);
	    break;
	case matchPushL:
	    if (!is_list(*ep))
		FAIL();
	    *sp++ = list_val(*ep);
	    ++ep;
	    break;
	case matchPop:
	    ep = *(--sp);
	    break;
	case matchBind:
	    n = *pc++;
	    hp[n] = *ep++;
	    break;
	case matchCmp:
	    n = *pc++;
	    if (!eq(hp[n],*ep))
		FAIL();
	    ++ep;
	    break;
	case matchEqBin:
	    t = (Eterm) *pc++;
	    if (!eq(*ep,t))
		FAIL();
	    ++ep;
	    break;
	case matchEqFloat:
	    if (!is_float(*ep))
		FAIL();
	    if (memcmp(float_val(*ep) + 1, pc, sizeof(double)))
		FAIL();
	    pc += 2;
	    ++ep;
	    break;
	case matchEqRef:
	    if (!is_ref(*ep))
		FAIL();
	    if (!eq(*ep, make_internal_ref(pc)))
		FAIL();
	    i = thing_arityval(*pc);
	    pc += i+1;
	    ++ep;
	    break;
	case matchEqBig:
	    if (!is_big(*ep))
		FAIL();
	    tp = big_val(*ep);
	    if (*tp != *pc)
		FAIL();
	    i = BIG_ARITY(pc);
	    while(i--)
		if (*++tp != *++pc)
		    FAIL();
	    ++pc;
	    ++ep;
	    break;
	case matchEq:
	    t = (Eterm) *pc++; 
	    if (t != *ep++)
		FAIL();
	    break;
	case matchSkip:
	    ++ep;
	    break;
	/* 
	 * Here comes guard instructions 
	 */
	case matchPushC: /* Push constant */
	    *esp++ = *pc++;
	    break;
	case matchConsA:
	    ehp[1] = *--esp;
	    ehp[0] = esp[-1];
	    esp[-1] = make_list(ehp);
	    ehp += 2;
	    break;
	case matchConsB:
	    ehp[0] = *--esp;
	    ehp[1] = esp[-1];
	    esp[-1] = make_list(ehp);
	    ehp += 2;
	    break;
	case matchMkTuple:
	    n = *pc++;
	    t = make_tuple(ehp);
	    *ehp++ = make_arityval(n);
	    while (n--) {
		*ehp++ = *--esp;
	    }
	    *esp++ = t;
	    break;
	case matchCall0:
	    bif = (Eterm (*)(Process*, ...)) *pc++;
	    t = (*bif)(psp);
	    if (is_non_value(t)) {
		if (do_catch)
		    t = FAIL_TERM;
		else
		    FAIL();
	    }
	    *esp++ = t;
	    break;
	case matchCall1:
	    bif = (Eterm (*)(Process*, ...)) *pc++;
	    t = (*bif)(psp, esp[-1]);
	    if (is_non_value(t)) {
		if (do_catch)
		    t = FAIL_TERM;
		else
		    FAIL();
	    }
	    esp[-1] = t;
	    break;
	case matchCall2:
	    bif = (Eterm (*)(Process*, ...)) *pc++;
	    t = (*bif)(psp, esp[-1], esp[-2]);
	    if (is_non_value(t)) {
		if (do_catch)
		    t = FAIL_TERM;
		else
		    FAIL();
	    }
	    --esp;
	    esp[-1] = t;
	    break;
	case matchCall3:
	    bif = (Eterm (*)(Process*, ...)) *pc++;
	    t = (*bif)(psp, esp[-1], esp[-2], esp[-3]);
	    if (is_non_value(t)) {
		if (do_catch)
		    t = FAIL_TERM;
		else
		    FAIL();
	    }
	    esp -= 2;
	    esp[-1] = t;
	    break;
	case matchPushV:
	    *esp++ = hp[*pc++];
	    break;
	case matchPushExpr:
	    *esp++ = term;
	    break;
	case matchPushArrayAsList:
	    n = arity; /* Only happens when 'term' is an array */
	    tp = (Eterm *) term;
	    *esp++  = make_list(ehp);
	    while (n--) {
		*ehp++ = *tp++;
		*ehp = make_list(ehp + 1);
		ehp++; /* As pointed out by Mikael Pettersson the expression
			  (*ehp++ = make_list(ehp + 1)) that I previously
			  had written here has undefined behaviour. */
	    }
	    ehp[-1] = NIL;
	    break;
	case matchPushArrayAsListU:
	    /* This instruction is NOT efficient. */
	    *esp++  = dpm_array_to_list(psp, (Eterm *) term, arity); 
	    break;
	case matchTrue:
	    if (*--esp != am_true)
		FAIL();
	    break;
	case matchOr:
	    n = *pc++;
	    t = am_false;
	    while (n--) {
		if (*--esp == am_true) {
		    t = am_true;
		} else if (*esp != am_false) {
		    esp -= n;
		    if (do_catch) {
			t = FAIL_TERM;
			break;
		    } else {
			FAIL();
		    }
		}
	    }
	    *esp++ = t;
	    break;
	case matchAnd:
	    n = *pc++;
	    t = am_true;
	    while (n--) {
		if (*--esp == am_false) {
		    t = am_false;
		} else if (*esp != am_true) {
		    esp -= n;
		    if (do_catch) {
			t = FAIL_TERM;
			break;
		    } else {
			FAIL();
		    }
		}
	    }
	    *esp++ = t;
	    break;
	case matchOrElse:
	    n = *pc++;
	    if (*--esp == am_true) {
		++esp;
		pc = (prog->text) + prog->labels[n];
	    } else if (*esp != am_false) {
		if (do_catch) {
		    *esp++ = FAIL_TERM;
		    pc = (prog->text) + prog->labels[n];;
		} else {
		    FAIL();
		}
	    }
	    break;
	case matchAndThen:
	    n = *pc++;
	    if (*--esp == am_false) {
		esp++;
		pc = (prog->text) + prog->labels[n];
	    } else if (*esp != am_true) {
		if (do_catch) {
		    *esp++ = FAIL_TERM;
		    pc = (prog->text) + prog->labels[n];;
		} else {
		    FAIL();
		}
	    }
	    break;
	case matchSelf:
	    *esp++ = c_p->id;
	    break;
	case matchWaste:
	    --esp;
	    break;
	case matchReturn:
	    ret = *--esp;
	    break;
	case matchProcessDump: {
	    erts_dsprintf_buf_t *dsbufp = erts_create_tmp_dsbuf(0);
	    print_process_info(ERTS_PRINT_DSBUF, (void *) dsbufp, c_p);
	    *esp++ = new_binary(psp, (byte *)dsbufp->str, (int)dsbufp->str_len);
	    erts_destroy_tmp_dsbuf(dsbufp);
	    break;
	}
	case matchDisplay: /* Debugging, not for production! */
	    erts_printf("%T\n", esp[-1]);
	    esp[-1] = am_true;
	    break;
	case matchSetReturnTrace:
	    *return_flags |= MATCH_SET_RETURN_TRACE;
	    *esp++ = am_true;
	    break;
	case matchSetExceptionTrace:
	    *return_flags |= MATCH_SET_EXCEPTION_TRACE;
	    *esp++ = am_true;
	    break;
	case matchIsSeqTrace:
	    if (SEQ_TRACE_TOKEN(c_p) != NIL)
		*esp++ = am_true;
	    else
		*esp++ = am_false;
	    break;
	case matchSetSeqToken:
	    t = erts_seq_trace(c_p, esp[-1], esp[-2], 0);
	    if (is_non_value(t)) {
		esp[-2] = FAIL_TERM;
	    } else {
		esp[-2] = t;
	    }
	    --esp;
	    break;
	case matchSetSeqTokenFake:
	    t = seq_trace_fake(c_p, esp[-1]);
	    if (is_non_value(t)) {
		esp[-2] = FAIL_TERM;
	    } else {
		esp[-2] = t;
	    }
	    --esp;
	    break;
	case matchGetSeqToken:
	    if (SEQ_TRACE_TOKEN(c_p) == NIL) 
		*esp++ = NIL;
	    else {
 		*esp++ = make_tuple(ehp);
 		ehp[0] = make_arityval(5);
 		ehp[1] = SEQ_TRACE_TOKEN_FLAGS(c_p);
 		ehp[2] = SEQ_TRACE_TOKEN_LABEL(c_p);
 		ehp[3] = SEQ_TRACE_TOKEN_SERIAL(c_p);
 		ehp[4] = SEQ_TRACE_TOKEN_SENDER(c_p);
 		ehp[5] = SEQ_TRACE_TOKEN_LASTCNT(c_p);
		ASSERT(SEQ_TRACE_TOKEN_ARITY(c_p) == 5);
		ASSERT(is_immed(ehp[1]));
		ASSERT(is_immed(ehp[2]));
		ASSERT(is_immed(ehp[3]));
		ASSERT(is_immed(ehp[5]));
		if(!is_immed(ehp[4])) {
		    Eterm *sender = &ehp[4];
		    ehp += 6;
		    *sender = copy_struct(*sender,
					  size_object(*sender),
					  &ehp,
					  &MSO(psp));
		}
		else
		    ehp += 6;

	    } 
	    break;
	case matchEnableTrace:
	    if ( (n = erts_trace_flag2bit(esp[-1]))) {
		BEGIN_ATOMIC_TRACE(c_p);
		set_tracee_flags(c_p, c_p->tracer_proc, 0, n);
		esp[-1] = am_true;
	    } else {
		esp[-1] = FAIL_TERM;
	    }
	    break;
	case matchEnableTrace2:
	    n = erts_trace_flag2bit((--esp)[-1]);
	    esp[-1] = FAIL_TERM;
	    if (n) {
		BEGIN_ATOMIC_TRACE(c_p);
		if ( (tmpp = get_proc(c_p, 0, esp[0], 0))) {
		    /* Always take over the tracer of the current process */
		    set_tracee_flags(tmpp, c_p->tracer_proc, 0, n);
		    esp[-1] = am_true;
		}
	    }
	    break;
	case matchDisableTrace:
	    if ( (n = erts_trace_flag2bit(esp[-1]))) {
		BEGIN_ATOMIC_TRACE(c_p);
		set_tracee_flags(c_p, c_p->tracer_proc, n, 0);
		esp[-1] = am_true;
	    } else {
		esp[-1] = FAIL_TERM;
	    }
	    break;
	case matchDisableTrace2:
	    n = erts_trace_flag2bit((--esp)[-1]);
	    esp[-1] = FAIL_TERM;
	    if (n) {
		BEGIN_ATOMIC_TRACE(c_p);
		if ( (tmpp = get_proc(c_p, 0, esp[0], 0))) {
		    /* Always take over the tracer of the current process */
		    set_tracee_flags(tmpp, c_p->tracer_proc, n, 0);
		    esp[-1] = am_true;
		}
	    }
	    break;
 	case matchCaller:
 	    if (!(c_p->cp) || !(hp = find_function_from_pc(c_p->cp))) {
 		*esp++ = am_undefined;
 	    } else {
 		*esp++ = make_tuple(ehp);
 		ehp[0] = make_arityval(3);
 		ehp[1] = hp[0];
 		ehp[2] = hp[1];
 		ehp[3] = make_small(hp[2]);
 		ehp += 4;
 	    }
 	    break;
	case matchSilent:
	    --esp;
	    if (*esp == am_true) {
		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
		c_p->trace_flags |= F_TRACE_SILENT;
		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
	    }
	    else if (*esp == am_false) {
		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
		c_p->trace_flags &= ~F_TRACE_SILENT;
		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
	    }
	    break;
	case matchTrace2:
	    {
		/*    disable         enable                                */
		Uint  d_flags  = 0,   e_flags  = 0;  /* process trace flags */
		Eterm tracer = c_p->tracer_proc;
		/* XXX Atomicity note: Not fully atomic. Default tracer
		 * is sampled from current process but applied to
		 * tracee and tracer later after releasing main
		 * locks on current process, so c_p->tracer_proc
		 * may actually have changed when tracee and tracer
		 * gets updated. I do not think nobody will notice.
		 * It is just the default value that is not fully atomic.
		 * and the real argument settable from match spec
		 * {trace,[],[{{tracer,Tracer}}]} is much, much older.
		 */
		int   cputs = 0;
		
		if (! erts_trace_flags(esp[-1], &d_flags, &tracer, &cputs) ||
		    ! erts_trace_flags(esp[-2], &e_flags, &tracer, &cputs) ||
		    cputs ) {
		    (--esp)[-1] = FAIL_TERM;
		    break;
		}
		erts_smp_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
		(--esp)[-1] = set_match_trace(c_p, FAIL_TERM, tracer,
					      d_flags, e_flags);
		erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
	    }
	    break;
	case matchTrace3:
	    {
		/*    disable         enable                                */
		Uint  d_flags  = 0,   e_flags  = 0;  /* process trace flags */
		Eterm tracer = c_p->tracer_proc;
		/* XXX Atomicity note. Not fully atomic. See above. 
		 * Above it could possibly be solved, but not here.
		 */
		int   cputs = 0;
		Eterm tracee = (--esp)[0];
		
		if (! erts_trace_flags(esp[-1], &d_flags, &tracer, &cputs) ||
		    ! erts_trace_flags(esp[-2], &e_flags, &tracer, &cputs) ||
		    cputs ||
		    ! (tmpp = get_proc(c_p, ERTS_PROC_LOCK_MAIN, 
				       tracee, ERTS_PROC_LOCKS_ALL))) {
		    (--esp)[-1] = FAIL_TERM;
		    break;
		}
		if (tmpp == c_p) {
		    (--esp)[-1] = set_match_trace(c_p, FAIL_TERM, tracer,
						  d_flags, e_flags);
		    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
		} else {
		    erts_smp_proc_unlock(c_p, ERTS_PROC_LOCK_MAIN);
		    (--esp)[-1] = set_match_trace(tmpp, FAIL_TERM, tracer,
						  d_flags, e_flags);
		    erts_smp_proc_unlock(tmpp, ERTS_PROC_LOCKS_ALL);
		    erts_smp_proc_lock(c_p, ERTS_PROC_LOCK_MAIN);
		}
	    }
	    break;
	case matchCatch:
	    do_catch = 1;
	    break;
	case matchHalt:
	    goto success;
	default:
	    erl_exit(1, "Internal error: unexpected opcode in match program.");
	}
    }
fail:
    *return_flags = 0U;
    if (fail_label >= 0) { /* We failed during a "TryMeElse", 
			      lets restart, with the next match 
			      program */
	pc = (prog->text) + fail_label;
	cleanup_match_pseudo_process(mpsp, 1);
	goto restart;
    }
    ret = THE_NON_VALUE;
success:

#ifdef DMC_DEBUG
    if (*heap_fence != FENCE_PATTERN) {
	erl_exit(1, "Heap fence overwritten in db_prog_match after op "
		 "0x%08x, overwritten with 0x%08x.", save_op, *heap_fence);
    }
    if (*eheap_fence != FENCE_PATTERN) {
	erl_exit(1, "Eheap fence overwritten in db_prog_match after op "
		 "0x%08x, overwritten with 0x%08x.", save_op, 
		 *eheap_fence);
    }
    if (*stack_fence != FENCE_PATTERN) {
	erl_exit(1, "Stack fence overwritten in db_prog_match after op "
		 "0x%08x, overwritten with 0x%08x.", save_op, 
		 *stack_fence);
    }
#endif

    esdp->current_process = current_scheduled;

    END_ATOMIC_TRACE(c_p);
    return ret;
#undef FAIL
#undef FAIL_TERM
#undef BEGIN_ATOMIC_TRACE
#undef END_ATOMIC_TRACE
}


/*
 * Convert a match program to a "magic" binary to return up to erlang