xref: /netbsd-src/external/bsd/elftoolchain/dist/libdwarf/dwarf_get_aranges.3 (revision 5ac3bc719ce6e70593039505b491894133237d12)
1.\"	$NetBSD: dwarf_get_aranges.3,v 1.6 2024/03/03 17:37:31 christos Exp $
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3.\" Copyright (c) 2011 Kai Wang
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27.\" Id: dwarf_get_aranges.3 3962 2022-03-12 15:56:10Z jkoshy
28.\"
29.Dd November 9, 2011
30.Dt DWARF_GET_ARANGES 3
31.Os
32.Sh NAME
33.Nm dwarf_get_aranges
34.Nd retrieve program address space mappings
35.Sh LIBRARY
36.Lb libdwarf
37.Sh SYNOPSIS
38.In libdwarf.h
39.Ft int
40.Fo dwarf_get_aranges
41.Fa "Dwarf_Debug dbg"
42.Fa "Dwarf_Arange **ar_list"
43.Fa "Dwarf_Signed *ar_cnt"
44.Fa "Dwarf_Error *err"
45.Fc
46.Sh DESCRIPTION
47The function
48.Fn dwarf_get_aranges
49retrieves address range information from the
50.Dq ".debug_aranges"
51DWARF section.
52Information about address ranges is returned using opaque descriptors
53of type
54.Vt Dwarf_Arange ,
55.Pp
56Argument
57.Fa dbg
58should reference a DWARF debug context allocated using
59.Xr dwarf_init 3 .
60.Pp
61Argument
62.Fa ar_list
63should point to a location which will be set to a pointer to an array
64of
65.Vt Dwarf_Arange
66descriptors.
67.Pp
68Argument
69.Fa ar_cnt
70should point to a location which will be set to the number of
71descriptors returned.
72.Pp
73If argument
74.Fa err
75is not
76.Dv NULL ,
77it will be used to store error information in case of an error.
78.Ss Memory Management
79The memory area used for the array returned in argument
80.Fa ar_list
81is owned by
82.Lb libdwarf .
83Application code should not attempt to directly free this area.
84Portable applications should instead use
85.Xr dwarf_dealloc 3
86to indicate that the memory area may be freed.
87.Sh RETURN VALUES
88Function
89.Fn dwarf_get_aranges
90returns
91.Dv DW_DLV_OK
92when it succeeds.
93It returns
94.Dv DW_DLV_NO_ENTRY
95if there is no
96.Dq ".debug_aranges"
97section associated with the specified debugging context.
98In case of an error, it returns
99.Dv DW_DLV_ERROR
100and sets the argument
101.Fa err .
102.Sh EXAMPLES
103To loop through all the address lookup table entries, use:
104.Bd -literal -offset indent
105Dwarf_Debug dbg;
106Dwarf_Addr start;
107Dwarf_Arange *aranges;
108Dwarf_Off die_off;
109Dwarf_Signed i, cnt;
110Dwarf_Unsigned length;
111Dwarf_Error de;
112
113if (dwarf_get_aranges(dbg, &aranges, &cnt, &de) != DW_DLV_OK)
114	errx(EXIT_FAILURE, "dwarf_get_aranges: %s",
115	    dwarf_errmsg(de));
116
117for (i = 0; i < cnt; i++) {
118	if (dwarf_get_arange_info(aranges[i], &start, &length,
119	    &die_off, &de) != DW_DLV_OK) {
120		warnx("dwarf_get_arange_info: %s",
121		    dwarf_errmsg(de));
122		continue;
123	}
124	/* Do something with the returned information. */
125}
126.Ed
127.Sh ERRORS
128Function
129.Fn dwarf_get_aranges
130can fail with:
131.Bl -tag -width ".Bq Er DW_DLE_NO_ENTRY"
132.It Bq Er DW_DLE_ARGUMENT
133One of the arguments
134.Fa dbg ,
135.Fa ar_list
136or
137.Fa ar_cnt
138was
139.Dv NULL .
140.It Bq Er DW_DLE_NO_ENTRY
141The debugging context
142.Fa dbg
143did not contain a
144.Dq ".debug_aranges"
145string section.
146.El
147.Sh SEE ALSO
148.Xr dwarf 3 ,
149.Xr dwarf_get_arange 3 ,
150.Xr dwarf_get_arange_cu_header_offset 3 ,
151.Xr dwarf_get_arange_info 3 ,
152.Xr dwarf_get_cu_die_offset 3
153