xref: /freebsd/contrib/elftoolchain/libelf/gelf_getrela.3 (revision 43a5ec4eb41567cc92586503212743d89686d78f)
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24.\" $Id: gelf_getrela.3 3734 2019-04-22 14:10:49Z jkoshy $
25.\"
26.Dd April 22, 2019
27.Dt GELF_GETRELA 3
28.Os
29.Sh NAME
30.Nm gelf_getrela ,
31.Nm gelf_update_rela
32.Nd read and update ELF relocation entries with addends
33.Sh LIBRARY
34.Lb libelf
35.Sh SYNOPSIS
36.In gelf.h
37.Ft "GElf_Rela *"
38.Fn gelf_getrela "Elf_Data *data" "int ndx" "GElf_Rela *rela"
39.Ft int
40.Fn gelf_update_rela "Elf_Data *data" "int ndx" "GElf_Rela *rela"
41.Sh DESCRIPTION
42These convenience functions are used to retrieve and update class-dependent
43.Vt Elf32_Rela
44or
45.Vt Elf64_Rela
46structures in an ELF object.
47.Pp
48Argument
49.Ar data
50is an
51.Vt Elf_Data
52descriptor associated with a section of type
53.Dv SHT_RELA .
54Argument
55.Ar ndx
56is the index of the entry being retrieved or updated.
57The class-independent
58.Vt GElf_Rela
59structure is described in
60.Xr gelf 3 .
61.Pp
62Function
63.Fn gelf_getrela
64retrieves the class-dependent entry at index
65.Ar ndx
66in data buffer
67.Ar data
68and copies it to the destination pointed to by argument
69.Ar rela
70after translation to class-independent form.
71.Pp
72Function
73.Fn gelf_update_rela
74converts the class-independent entry pointed to
75by argument
76.Ar rela
77to class-dependent form, and writes it to the entry at index
78.Ar ndx
79in the data buffer described by argument
80.Ar data .
81Function
82.Fn gelf_update_rela
83signals an error if any of the values in the class-independent
84representation exceeds the representable limits of the target
85type.
86.Sh RETURN VALUES
87Function
88.Fn gelf_getrela
89returns the value of argument
90.Ar rela
91if successful, or NULL in case of an error.
92Function
93.Fn gelf_update_rela
94returns a non-zero value if successful, or zero in case of an error.
95.Sh ERRORS
96These functions may fail with the following errors:
97.Bl -tag -width "[ELF_E_RESOURCE]"
98.It Bq Er ELF_E_ARGUMENT
99Arguments
100.Ar data
101or
102.Ar rela
103were NULL.
104.It Bq Er ELF_E_ARGUMENT
105Argument
106.Ar ndx
107was less than zero or larger than the number of entries in the data
108descriptor.
109.It Bq Er ELF_E_ARGUMENT
110Data descriptor
111.Ar data
112was not associated with a section of type
113.Dv SHT_RELA .
114.It Bq Er ELF_E_RANGE
115A value was not representable in the target type.
116.It Bq Er ELF_E_VERSION
117The
118.Vt Elf_Data
119descriptor denoted by argument
120.Ar data
121is associated with an ELF object with an unsupported version.
122.El
123.Sh SEE ALSO
124.Xr elf 3 ,
125.Xr elf_getdata 3 ,
126.Xr elf_getscn 3 ,
127.Xr gelf 3
128