xref: /freebsd/contrib/elftoolchain/libdwarf/dwarf_expr_into_block.3 (revision 02e9120893770924227138ba49df1edb3896112a)
1.\" Copyright (c) 2011 Kai Wang
2.\" All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\"
13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23.\" SUCH DAMAGE.
24.\"
25.\" $Id: dwarf_expr_into_block.3 3640 2018-10-14 14:09:13Z jkoshy $
26.\"
27.Dd September 13, 2011
28.Dt DWARF_EXPR_INTO_BLOCK 3
29.Os
30.Sh NAME
31.Nm dwarf_expr_into_block
32.Nd retrieve the byte stream for a location expression
33.Sh LIBRARY
34.Lb libdwarf
35.Sh SYNOPSIS
36.In libdwarf.h
37.Ft "Dwarf_Addr"
38.Fo dwarf_expr_into_block
39.Fa "Dwarf_P_Expr expr"
40.Fa "Dwarf_Unsigned *length"
41.Fa "Dwarf_Error *err"
42.Fc
43.Sh DESCRIPTION
44Function
45.Fn dwarf_expr_into_block
46retrieves the byte stream representation of a location expression.
47.Pp
48Argument
49.Ar expr
50should reference a location expression descriptor allocated using
51.Xr dwarf_new_expr 3 .
52.Pp
53Argument
54.Ar length
55should point to a location which will hold the size in bytes of
56the retrieved byte stream.
57.Pp
58If argument
59.Ar err
60is not NULL, it will be used to store error information in case
61of an error.
62.Sh RETURN VALUES
63On success, function
64.Fn dwarf_expr_into_block
65returns the address of the first byte of the generated byte stream.
66In case of an error, function
67.Fn dwarf_expr_into_block
68returns
69.Dv DW_DLV_BADADDR
70and sets the argument
71.Ar err .
72.Sh ERRORS
73Function
74.Fn dwarf_expr_into_block
75can fail with:
76.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
77.It Bq Er DW_DLE_ARGUMENT
78One of the arguments
79.Ar expr
80or
81.Ar length
82was NULL.
83.It Bq Er DW_DLE_MEMORY
84An out of memory condition was encountered during the execution of
85the function.
86.El
87.Sh SEE ALSO
88.Xr dwarf 3 ,
89.Xr dwarf_add_AT_location_expr 3 ,
90.Xr dwarf_add_expr_addr 3 ,
91.Xr dwarf_add_expr_addr_b 3 ,
92.Xr dwarf_add_expr_gen 3 ,
93.Xr dwarf_expr_current_offset 3 ,
94.Xr dwarf_new_expr 3
95