freebsd-skq/contrib/elftoolchain/libelf/elf_open.3
emaste a4c24f2588 Update to ELF Tool Chain r3197
Highlights:
 - Fix man page markup, whitespace, and typos
 - Fix sh_info of SHT_GROUP section to point to the correct string
 - Improve validation in readelf and elfcopy/strip
 - Handle DWARF 4's DW_AT_high_pc in addr2line

Sponsored by:	The FreeBSD Foundation
2015-05-14 19:48:15 +00:00

122 lines
3.4 KiB
Groff

.\" Copyright (c) 2012 Joseph Koshy. All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
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.\" 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
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.\" 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)
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.\" $Id: elf_open.3 3181 2015-04-10 13:22:51Z emaste $
.\"
.Dd May 31, 2012
.Os
.Dt ELF_OPEN 3
.Sh NAME
.Nm elf_open
.Nd open ELF objects and ar(1) archives
.Sh LIBRARY
.Lb libelf
.Sh SYNOPSIS
.In libelf.h
.Ft "Elf *"
.Fn elf_open "int fd"
.Ft "Elf *"
.Fn elf_openmemory "char *image" "size_t sz"
.Sh DESCRIPTION
.Em Important :
The functions
.Fn elf_open
and
.Fn elf_openmemory
are extensions to the ELF(3) API, for the internal use of the
Elftoolchain project.
Portable applications should not use these functions.
.Pp
The function
.Fn elf_open
returns an Elf descriptor opened with mode
.Dv ELF_C_READ
for the ELF object or
.Xr ar 1
archive referenced by the file descriptor in argument
.Ar fd .
.Pp
The function
.Fn elf_openmemory
returns an ELF descriptor opened with mode
.Dv ELF_C_READ
for the ELF object or
.Xr ar 1
archive contained in the memory area pointed to by the argument
.Ar image .
The argument
.Ar sz
specifies the size of the memory area in bytes.
.Sh COMPATIBILITY
These functions are non-standard extensions to the ELF(3) API set.
.Pp
The behavior of these functions differs from their counterparts
.Xr elf_begin 3
and
.Xr elf_memory 3
in that these functions will successfully open malformed ELF objects
and
.Xr ar 1
archives, returning an Elf descriptor of type
.Dv ELF_K_NONE .
.Sh RETURN VALUES
The function returns a pointer to a ELF descriptor if successful, or
NULL if an error occurred.
.Sh ERRORS
These functions can fail with the following errors:
.Bl -tag -width "[ELF_E_RESOURCE]"
.It Bq Er ELF_E_ARGUMENT
The argument
.Ar fd
was of an unsupported file type.
.It Bq Er ELF_E_ARGUMENT
The argument
.Ar sz
was zero, or the argument
.Ar image
was NULL.
.It Bq Er ELF_E_IO
The file descriptor in argument
.Ar fd
was invalid.
.It Bq Er ELF_E_IO
The file descriptor in argument
.Ar fd
could not be read.
.It Bq Er ELF_E_RESOURCE
An out of memory condition was encountered.
.It Bq Er ELF_E_SEQUENCE
Functions
.Fn elf_open
or
.Fn elf_openmemory
was called before a working version was established with
.Xr elf_version 3 .
.El
.Sh SEE ALSO
.Xr elf 3 ,
.Xr elf_begin 3 ,
.Xr elf_errno 3 ,
.Xr elf_memory 3 ,
.Xr gelf 3