1.\" $NetBSD: dwarf_formudata.3,v 1.2 2014/03/09 16:58:03 christos Exp $ 2.\" 3.\" Copyright (c) 2010 Joseph Koshy 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_formudata.3 2073 2011-10-27 03:30:47Z jkoshy 28.\" 29.Dd June 21, 2010 30.Os 31.Dt DWARF_FORMUDATA 3 32.Sh NAME 33.Nm dwarf_formudata , 34.Nm dwarf_formsdata 35.Nd return the value of a CONSTANT class attribute 36.Sh LIBRARY 37.Lb libdwarf 38.Sh SYNOPSIS 39.In libdwarf.h 40.Ft int 41.Fo dwarf_formudata 42.Fa "Dwarf_Attribute attr" 43.Fa "Dwarf_Unsigned *ret" 44.Fa "Dwarf_Error *err" 45.Fc 46.Ft int 47.Fo dwarf_formsdata 48.Fa "Dwarf_Attribute attr" 49.Fa "Dwarf_Signed *ret" 50.Fa "Dwarf_Error *err" 51.Fc 52.Sh DESCRIPTION 53These functions return the value associated with a DWARF attribute 54describing a constant. 55.Pp 56Function 57.Fn dwarf_formudata 58sets the location pointed to by argument 59.Ar ret 60to the value of the attribute referenced by argument 61.Ar attr , 62treating the value as an unsigned quantity. 63Argument 64.Ar attr 65must have one of the following forms: 66.Dv DW_FORM_data1 , 67.Dv DW_FORM_data2 , 68.Dv DW_FORM_data4 , 69.Dv DW_FORM_data8 70and 71.Dv DW_FORM_udata . 72.Pp 73Function 74.Fn dwarf_formsdata 75sets the location pointed to by argument 76.Ar ret 77to the value of the attribute referenced by argument 78.Ar attr , 79appropriately sign extended. 80Argument 81.Ar attr 82must have one of the following forms: 83.Dv DW_FORM_data1 , 84.Dv DW_FORM_data2 , 85.Dv DW_FORM_data4 , 86.Dv DW_FORM_data8 87and 88.Dv DW_FORM_sdata . 89.Pp 90If argument 91.Ar err 92is not NULL, it will be used to return an error descriptor in case 93of an error. 94.Sh RETURN VALUES 95These functions return 96.Dv DW_DLV_OK 97on success. 98In case of an error, they return 99.Dv DW_DLV_ERROR 100and set argument 101.Ar err . 102.Sh ERRORS 103These functions may fail with the following errors: 104.Bl -tag -width ".Bq Er DW_DLE_ATTR_FORM_BAD" 105.It Bq Er DW_DLE_ARGUMENT 106Either of arguments 107.Ar attr 108or 109.Ar ret 110was NULL. 111.It Bq Er DW_DLE_ATTR_FORM_BAD 112The attribute referenced by argument 113.Ar attr 114was not of a permitted kind. 115.El 116.Sh SEE ALSO 117.Xr dwarf 3 , 118.Xr dwarf_attr 3 , 119.Xr dwarf_formblock 3 , 120.Xr dwarf_formflag 3 , 121.Xr dwarf_formref 3 , 122.Xr dwarf_formsig8 3 , 123.Xr dwarf_formstring 3 , 124.Xr dwarf_hasattr 3 125