xref: /freebsd/contrib/elftoolchain/libdwarf/dwarf_formexprloc.3 (revision 2de3b87a120614a3b053be7dd845b72f1e9ce804)
1*2de3b87aSKai Wang.\" Copyright (c) 2010 Joseph Koshy
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25*2de3b87aSKai Wang.\" $Id: dwarf_formexprloc.3 2073 2011-10-27 03:30:47Z jkoshy $
26*2de3b87aSKai Wang.\"
27*2de3b87aSKai Wang.Dd July 25, 2010
28*2de3b87aSKai Wang.Os
29*2de3b87aSKai Wang.Dt DWARF_FORMEXPRLOC 3
30*2de3b87aSKai Wang.Sh NAME
31*2de3b87aSKai Wang.Nm dwarf_formexprloc
32*2de3b87aSKai Wang.Nd return information about a location expression
33*2de3b87aSKai Wang.Sh LIBRARY
34*2de3b87aSKai Wang.Lb libdwarf
35*2de3b87aSKai Wang.Sh SYNOPSIS
36*2de3b87aSKai Wang.In libdwarf.h
37*2de3b87aSKai Wang.Ft int
38*2de3b87aSKai Wang.Fo dwarf_formexprloc
39*2de3b87aSKai Wang.Fa "Dwarf_Attribute attr"
40*2de3b87aSKai Wang.Fa "Dwarf_Unsigned *retlen"
41*2de3b87aSKai Wang.Fa "Dwarf_Ptr *retexpr"
42*2de3b87aSKai Wang.Fa "Dwarf_Error *err"
43*2de3b87aSKai Wang.Fc
44*2de3b87aSKai Wang.Sh DESCRIPTION
45*2de3b87aSKai WangFunction
46*2de3b87aSKai Wang.Fn dwarf_formexprloc
47*2de3b87aSKai Wangallows an application to retrieve the length and the bytes of a
48*2de3b87aSKai WangDWARF location expression.
49*2de3b87aSKai Wang.Pp
50*2de3b87aSKai WangArgument
51*2de3b87aSKai Wang.Ar attr
52*2de3b87aSKai Wangshould reference a DWARF attribute of the form
53*2de3b87aSKai Wang.Dv DW_FORM_exprloc .
54*2de3b87aSKai WangArgument
55*2de3b87aSKai Wang.Ar retlen
56*2de3b87aSKai Wangshould point to a location that will be set to the length of the
57*2de3b87aSKai Wanglocation expression.
58*2de3b87aSKai WangArgument
59*2de3b87aSKai Wang.Ar retexpr
60*2de3b87aSKai Wangshould point to a location that will be set to a pointer to the
61*2de3b87aSKai Wangcontent of the location expression itself.
62*2de3b87aSKai Wang.Pp
63*2de3b87aSKai WangIf argument
64*2de3b87aSKai Wang.Ar err
65*2de3b87aSKai Wangis not NULL, it will be used to return an error descriptor in case
66*2de3b87aSKai Wangof an error.
67*2de3b87aSKai Wang.Ss Memory Management
68*2de3b87aSKai WangThe application should not attempt to free the memory
69*2de3b87aSKai Wangarea referenced by the pointer returned in argument
70*2de3b87aSKai Wang.Ar retexpr .
71*2de3b87aSKai Wang.Sh RETURN VALUES
72*2de3b87aSKai WangFunction
73*2de3b87aSKai Wang.Fn dwarf_formexprloc
74*2de3b87aSKai Wangreturns
75*2de3b87aSKai Wang.Dv DW_DLV_OK
76*2de3b87aSKai Wangon success.
77*2de3b87aSKai WangIn case of an error, it returns
78*2de3b87aSKai Wang.Dv DW_DLV_ERROR
79*2de3b87aSKai Wangand sets argument
80*2de3b87aSKai Wang.Ar err .
81*2de3b87aSKai Wang.Sh ERRORS
82*2de3b87aSKai WangFunction
83*2de3b87aSKai Wang.Fn dwarf_formexprloc
84*2de3b87aSKai Wangmay fail with the following errors:
85*2de3b87aSKai Wang.Bl -tag -width ".Bq Er DW_DLE_ATTR_FORM_BAD"
86*2de3b87aSKai Wang.It Bq Er DW_DLE_ARGUMENT
87*2de3b87aSKai WangOne of arguments
88*2de3b87aSKai Wang.Ar attr ,
89*2de3b87aSKai Wang.Ar retlen
90*2de3b87aSKai Wangor
91*2de3b87aSKai Wang.Ar retexpr
92*2de3b87aSKai Wangwas NULL.
93*2de3b87aSKai Wang.It Bq Er DW_DLE_ATTR_FORM_BAD
94*2de3b87aSKai WangThe attribute referenced by argument
95*2de3b87aSKai Wang.Ar attr
96*2de3b87aSKai Wangwas not of form
97*2de3b87aSKai Wang.Dv DW_FORM_exprloc .
98*2de3b87aSKai Wang.El
99*2de3b87aSKai Wang.Sh SEE ALSO
100*2de3b87aSKai Wang.Xr dwarf 3 ,
101*2de3b87aSKai Wang.Xr dwarf_attr 3 ,
102*2de3b87aSKai Wang.Xr dwarf_formblock 3 ,
103*2de3b87aSKai Wang.Xr dwarf_formflag 3 ,
104*2de3b87aSKai Wang.Xr dwarf_formref 3 ,
105*2de3b87aSKai Wang.Xr dwarf_formsdata 3 ,
106*2de3b87aSKai Wang.Xr dwarf_formsig8 3 ,
107*2de3b87aSKai Wang.Xr dwarf_formstring 3 ,
108*2de3b87aSKai Wang.Xr dwarf_formudata 3 ,
109*2de3b87aSKai Wang.Xr dwarf_hasattr 3
110