1.\" $NetBSD: dwarf_add_AT_location_expr.3,v 1.6 2024/03/03 17:37:30 christos Exp $ 2.\" 3.\" Copyright (c) 2011 Kai Wang 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" Id: dwarf_add_AT_location_expr.3 3961 2022-03-12 15:13:22Z jkoshy 28.\" 29.Dd September 5, 2011 30.Dt DWARF_ADD_AT_LOCATION_EXPR 3 31.Os 32.Sh NAME 33.Nm dwarf_add_AT_location_expr 34.Nd create an attribute descriptor for a location expression 35.Sh LIBRARY 36.Lb libdwarf 37.Sh SYNOPSIS 38.In libdwarf.h 39.Ft "Dwarf_P_Attribute" 40.Fo dwarf_add_AT_location_expr 41.Fa "Dwarf_P_Debug dbg" 42.Fa "Dwarf_P_Die die" 43.Fa "Dwarf_Half attr" 44.Fa "Dwarf_P_Expr loc_expr" 45.Fa "Dwarf_Error *err" 46.Fc 47.Sh DESCRIPTION 48Function 49.Fn dwarf_add_AT_location_expr 50creates an attribute descriptor for a location expression and attaches 51it to the debugging information entry referenced by argument 52.Fa die . 53.Pp 54Argument 55.Fa dbg 56should reference a DWARF producer instance allocated using 57.Xr dwarf_producer_init 3 58or 59.Xr dwarf_producer_init_b 3 . 60.Pp 61Argument 62.Fa die 63should reference a debugging information entry allocated using 64.Xr dwarf_new_die 3 . 65.Pp 66Argument 67.Fa attr 68specifies the attribute code of the created attribute descriptor. 69.Pp 70Argument 71.Fa loc_expr 72should reference a location expression descriptor allocated using 73.Xr dwarf_new_expr 3 . 74.Pp 75The attribute created by function 76.Fn dwarf_add_AT_location_expr 77will have one of the DWARF forms 78.Dv DW_FORM_block , 79.Dv DW_FORM_block1 , 80.Dv DW_FORM_block2 81or 82.Dv DW_FORM_block4 , 83depending on the size of the byte stream generated by the location 84expression descriptor referenced by argument 85.Fa loc_expr . 86.Pp 87If argument 88.Fa err 89is not 90.Dv NULL , 91it will be used by to store error information in case of an error. 92.Sh RETURN VALUES 93On success, function 94.Fn dwarf_add_AT_location_expr 95returns the created attribute descriptor. 96In case of an error, function 97.Fn dwarf_add_AT_location_expr 98returns 99.Dv DW_DLV_BADADDR 100and sets the argument 101.Fa err . 102.Sh ERRORS 103Function 104.Fn dwarf_add_AT_location_expr 105can fail with: 106.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT" 107.It Bq Er DW_DLE_ARGUMENT 108One of the arguments 109.Fa dbg , 110.Fa die 111or 112.Fa loc_expr 113was 114.Dv NULL . 115.It Bq Er DW_DLE_MEMORY 116An out of memory condition was encountered during the execution of the 117function. 118.El 119.Sh SEE ALSO 120.Xr dwarf 3 , 121.Xr dwarf_new_die 3 , 122.Xr dwarf_new_expr 3 , 123.Xr dwarf_producer_init 3 , 124.Xr dwarf_producer_init_b 3 125