xref: /freebsd/contrib/elftoolchain/libdwarf/dwarf_attr.3 (revision ae500c1ff8974130f7f2692772cf288b90349e0d)
12de3b87aSKai Wang.\" Copyright (c) 2010 Kai Wang
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72de3b87aSKai Wang.\" 1. Redistributions of source code must retain the above copyright
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92de3b87aSKai Wang.\" 2. Redistributions in binary form must reproduce the above copyright
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152de3b87aSKai Wang.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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25*ae500c1fSEd Maste.\" $Id: dwarf_attr.3 3644 2018-10-15 19:55:01Z jkoshy $
262de3b87aSKai Wang.\"
272de3b87aSKai Wang.Dd April 8, 2010
282de3b87aSKai Wang.Dt DWARF_ATTR 3
29*ae500c1fSEd Maste.Os
302de3b87aSKai Wang.Sh NAME
312de3b87aSKai Wang.Nm dwarf_attr
322de3b87aSKai Wang.Nd retrieve an attribute descriptor associated with a DWARF debugging information entry
332de3b87aSKai Wang.Sh LIBRARY
342de3b87aSKai Wang.Lb libdwarf
352de3b87aSKai Wang.Sh SYNOPSIS
362de3b87aSKai Wang.In libdwarf.h
372de3b87aSKai Wang.Ft int
382de3b87aSKai Wang.Fo dwarf_attr
392de3b87aSKai Wang.Fa "Dwarf_Die die"
402de3b87aSKai Wang.Fa "Dwarf_Half attr"
412de3b87aSKai Wang.Fa "Dwarf_Attribute *atp"
422de3b87aSKai Wang.Fa "Dwarf_Error *err"
432de3b87aSKai Wang.Fc
442de3b87aSKai Wang.Sh DESCRIPTION
452de3b87aSKai WangFunction
462de3b87aSKai Wang.Fn dwarf_attr
472de3b87aSKai Wangretrieves the attribute descriptor for an attribute associated
482de3b87aSKai Wangwith the DWARF debugging information entry descriptor in
492de3b87aSKai Wangargument
502de3b87aSKai Wang.Ar die .
512de3b87aSKai Wang.Pp
522de3b87aSKai WangDWARF attribute descriptors are represented by value of the opaque
532de3b87aSKai Wangtype
542de3b87aSKai Wang.Vt Dwarf_Attribute ,
552de3b87aSKai Wangsee
562de3b87aSKai Wang.Xr dwarf 3 .
572de3b87aSKai Wang.Pp
582de3b87aSKai WangArgument
592de3b87aSKai Wang.Ar attr
602de3b87aSKai Wangnames the desired DWARF attribute.
612de3b87aSKai WangLegal values for argument
622de3b87aSKai Wang.Ar attr
632de3b87aSKai Wangare those denoted by the
642de3b87aSKai Wang.Dv DW_AT_*
652de3b87aSKai Wangconstants in the DWARF specification.
662de3b87aSKai Wang.Pp
672de3b87aSKai WangArgument
682de3b87aSKai Wang.Ar atp
692de3b87aSKai Wangpoints to a location into which the returned attribute descriptor
702de3b87aSKai Wangwill be written.
712de3b87aSKai WangThe returned descriptor may then be passed to the form query functions in the
722de3b87aSKai Wang.Xr dwarf 3
732de3b87aSKai WangAPI set to access the data associated with the attribute.
742de3b87aSKai Wang.Pp
752de3b87aSKai WangIf argument
762de3b87aSKai Wang.Ar err
772de3b87aSKai Wangis non-NULL, it will be used to return an error descriptor in case
782de3b87aSKai Wangof an error.
792de3b87aSKai Wang.Sh RETURN VALUES
802de3b87aSKai WangFunction
812de3b87aSKai Wang.Fn dwarf_attr
822de3b87aSKai Wangreturns
83*ae500c1fSEd Maste.Dv DW_DLV_OK
84*ae500c1fSEd Masteon success.
852de3b87aSKai Wang.Pp
862de3b87aSKai WangIf the debugging information entry descriptor denoted by argument
872de3b87aSKai Wang.Ar die
882de3b87aSKai Wangdoes not contain the named attribute, the function returns
892de3b87aSKai Wang.Dv DW_DLV_NO_ENTRY
902de3b87aSKai Wangand sets argument
912de3b87aSKai Wang.Ar err .
922de3b87aSKai WangFor other errors, it returns
932de3b87aSKai Wang.Dv DW_DLV_ERROR
942de3b87aSKai Wangand sets argument
952de3b87aSKai Wang.Ar err .
962de3b87aSKai Wang.Sh ERRORS
972de3b87aSKai WangFunction
982de3b87aSKai Wang.Fn dwarf_attr
992de3b87aSKai Wangcan fail with the following errors:
1002de3b87aSKai Wang.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
1012de3b87aSKai Wang.It Bq Er DW_DLE_ARGUMENT
1022de3b87aSKai WangEither of arguments
1032de3b87aSKai Wang.Ar die
1042de3b87aSKai Wangor
1052de3b87aSKai Wang.Ar atp
1062de3b87aSKai Wangwas NULL.
1072de3b87aSKai Wang.It Bq Er DW_DLE_NO_ENTRY
1082de3b87aSKai WangArgument
1092de3b87aSKai Wang.Ar die
1102de3b87aSKai Wanghad no attribute corresponding to the value
1112de3b87aSKai Wangin argument
1122de3b87aSKai Wang.Ar attr .
1132de3b87aSKai Wang.El
1142de3b87aSKai Wang.Sh SEE ALSO
1152de3b87aSKai Wang.Xr dwarf 3 ,
1162de3b87aSKai Wang.Xr dwarf_attrlist 3 ,
117cf781b2eSEd Maste.Xr dwarf_attroffset 3 ,
1182de3b87aSKai Wang.Xr dwarf_hasattr 3 ,
1192de3b87aSKai Wang.Xr dwarf_hasform 3 ,
1202de3b87aSKai Wang.Xr dwarf_whatattr 3 ,
1212de3b87aSKai Wang.Xr dwarf_whatform 3
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