3960614646
Although groff_mdoc(7) gives another impression, this is the ordering most widely used and also required by mdocml/mandoc. Reviewed by: ru Approved by: philip, ed (mentors)
202 lines
6.2 KiB
Groff
202 lines
6.2 KiB
Groff
.\" Copyright (c) 2006 Joseph Koshy. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" This software is provided by Joseph Koshy ``as is'' and
|
|
.\" any express or implied warranties, including, but not limited to, the
|
|
.\" implied warranties of merchantability and fitness for a particular purpose
|
|
.\" are disclaimed. in no event shall Joseph Koshy be liable
|
|
.\" for any direct, indirect, incidental, special, exemplary, or consequential
|
|
.\" damages (including, but not limited to, procurement of substitute goods
|
|
.\" or services; loss of use, data, or profits; or business interruption)
|
|
.\" however caused and on any theory of liability, whether in contract, strict
|
|
.\" liability, or tort (including negligence or otherwise) arising in any way
|
|
.\" out of the use of this software, even if advised of the possibility of
|
|
.\" such damage.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd September 1, 2006
|
|
.Dt GELF 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm GElf
|
|
.Nd class-independent API for ELF manipulation
|
|
.Sh LIBRARY
|
|
.Lb libelf
|
|
.Sh SYNOPSIS
|
|
.In gelf.h
|
|
.Sh DESCRIPTION
|
|
This manual page describes a class independent API for manipulating
|
|
ELF objects.
|
|
This API allows an application to operate on ELF descriptors without
|
|
needing to the know the ELF class of the descriptor.
|
|
.Pp
|
|
The GElf API may be used alongside the ELF API without restriction.
|
|
.Ss GElf Data Structures
|
|
The GElf API defines the following class-independent data structures:
|
|
.Bl -tag -width GElf_Sxword
|
|
.It Vt GElf_Addr
|
|
A representation of ELF addresses.
|
|
.It Vt GElf_Dyn
|
|
A class-independent representation of ELF
|
|
.Sy .dynamic
|
|
section entries.
|
|
.It Vt GElf_Ehdr
|
|
A class-independent representation of an ELF Executable Header.
|
|
.It Vt GElf_Half
|
|
An unsigned 16 bit quantity.
|
|
.It Vt GElf_Off
|
|
A class-independent representation of a ELF offset.
|
|
.It Vt GElf_Phdr
|
|
A class-independent representation of an ELF Program Header Table
|
|
entry.
|
|
.It Vt GElf_Rel
|
|
A class-independent representation of an ELF relocation entry.
|
|
.It Vt GElf_Rela
|
|
A class-independent representation of an ELF relocation entry with
|
|
addend.
|
|
.It Vt GElf_Shdr
|
|
A class-independent representation of an ELF Section Header Table
|
|
entry.
|
|
.It Vt GElf_Sword
|
|
A signed 32 bit quantity.
|
|
.It Vt GElf_Sxword
|
|
A signed 64 bit quantity.
|
|
.It Vt GElf_Sym
|
|
A class-independent representation of an ELF symbol table entry.
|
|
.It Vt GElf_Word
|
|
An unsigned 32 bit quantity.
|
|
.It Vt GElf_Xword
|
|
An unsigned 64 bit quantity.
|
|
.El
|
|
.Pp
|
|
These data structures are sized to be compatible with the
|
|
corresponding 64 bit ELF structures, and have the same internal
|
|
structure as their 64 bit class-dependent counterparts.
|
|
Class-dependent ELF structures are described in
|
|
.Xr elf 5 .
|
|
.Ss GElf Programming Model
|
|
GElf functions always return a
|
|
.Em copy
|
|
of the underlying (class-dependent) ELF data structure.
|
|
The programming model with GElf is as follows:
|
|
.Bl -enum
|
|
.It
|
|
An application will retrieve data from an ELF descriptor using a
|
|
.Fn gelf_get_*
|
|
function.
|
|
This will copy out data into a private
|
|
.Vt GElf_*
|
|
data structure.
|
|
.It
|
|
The application will work with its private copy of the GElf
|
|
structure.
|
|
.It
|
|
Once done, the application copies the new values back to the
|
|
underlying ELF data structure using the
|
|
.Fn gelf_update_*
|
|
functions.
|
|
.It
|
|
The application will then use the
|
|
.Fn elf_flag*
|
|
APIs to indicate to the ELF library that an ELF data structure is dirty.
|
|
.El
|
|
.Pp
|
|
When updating an underlying 32 bit ELF data structure, the GElf
|
|
routines will signal an error if a GElf value is out of range
|
|
for the underlying ELF data type.
|
|
.Ss Namespace use
|
|
The GElf interface uses the following symbols:
|
|
.Bl -tag
|
|
.It GElf_*
|
|
Class-independent data types.
|
|
.It gelf_*
|
|
For functions defined in the API set.
|
|
.El
|
|
.Ss GElf Programming APIs
|
|
This section provides an overview of the GElf programming APIs.
|
|
Further information is provided in the manual page of each function
|
|
listed here.
|
|
.Bl -tag
|
|
.It "Allocating ELF Data Structures"
|
|
.Bl -tag -compact
|
|
.It Fn gelf_newehdr
|
|
Allocate a new ELF Executable Header.
|
|
.It Fn gelf_newphdr
|
|
Allocate a new ELF Program Header Table.
|
|
.El
|
|
.It "Data Translation"
|
|
.Bl -tag -compact
|
|
.It Fn gelf_xlatetof
|
|
Translate the native representation of an ELF data structure to its
|
|
file representation.
|
|
.It Fn gelf_xlatetom
|
|
Translate from the file representation of an ELF data structure to a
|
|
native representation.
|
|
.El
|
|
.It "Retrieving ELF Data"
|
|
.Bl -tag -compact
|
|
.It Fn gelf_getdyn
|
|
Retrieve an ELF
|
|
.Sy .dynamic
|
|
table entry.
|
|
.It Fn gelf_getehdr
|
|
Retrieve an ELF Executable Header from the underlying ELF descriptor.
|
|
.It Fn gelf_getphdr
|
|
Retrieve an ELF Program Header Table entry from the underlying ELF descriptor.
|
|
.It Fn gelf_getrel
|
|
Retrieve an ELF relocation entry.
|
|
.It Fn gelf_getrela
|
|
Retrieve an ELF relocation entry with addend.
|
|
.It Fn gelf_getshdr
|
|
Retrieve an ELF Section Header Table entry from the underlying ELF descriptor.
|
|
.It Fn gelf_getsym
|
|
Retrieve an ELF symbol table entry.
|
|
.El
|
|
.It Queries
|
|
.Bl -tag -compact
|
|
.It Fn gelf_checksum
|
|
Retrieves the ELF checksum for an ELF descriptor.
|
|
.It Fn gelf_fsize
|
|
Retrieves the size of the file representation of an ELF type.
|
|
.It Fn gelf_getclass
|
|
Retrieves the ELF class of an ELF descriptor.
|
|
.El
|
|
.It "Updating ELF Data"
|
|
.Bl -tag -compact -width ".Fn gelf_update_shdr"
|
|
.It Fn gelf_update_dyn
|
|
Copy back an ELF
|
|
.Sy .dynamic
|
|
Table entry.
|
|
.It Fn gelf_update_phdr
|
|
Copy back an ELF Program Header Table entry.
|
|
.It Fn gelf_update_rel
|
|
Copy back an ELF relocation entry.
|
|
.It Fn gelf_update_rela
|
|
Copy back an ELF relocation with addend entry.
|
|
.It Fn gelf_update_shdr
|
|
Copy back an ELF Section Header Table entry.
|
|
.It Fn gelf_update_sym
|
|
Copy back an ELF symbol table entry.
|
|
.El
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr elf 3 ,
|
|
.Xr elf 5
|
|
.Sh HISTORY
|
|
The GELF(3) API first appeared in System V Release 4.
|
|
This implementation of the API first appeared in
|
|
.Fx 7.0 .
|
|
.Sh AUTHORS
|
|
The GElf API was implemented by
|
|
.An "Joseph Koshy"
|
|
.Aq jkoshy@FreeBSD.org .
|