.\" Man page written by Jozsef Kadlecsik <kadlec@netfilter.org>
.\" 
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.TH libipset 3 "Oct 16, 2018" "Jozsef Kadlecsik" ""
.SH NAME
libipset \- A library for using ipset
.SH SYNOPSIS
.nf
#include <libipset/ipset.h>
.sp
void ipset_load_types(void)
.sp
struct ipset * ipset_init(void)
int ipset_parse_argv(struct ipset *ipset, int argc, char *argv[])
.sp
int ipset_parse_line(struct ipset *ipset, char *line)
.sp
int ipset_parse_stream(struct ipset *ipset, FILE *f)
.sp
int ipset_fini(struct ipset *ipset)
.sp
int ipset_custom_printf(struct ipset *ipset,
			ipset_custom_errorfn custom_error,
			ipset_standard_errorfn standard_error,
			ipset_print_outfn outfn,
			void *p)
.sp
struct ipset_session * ipset_session(struct ipset *ipset)
.sp
int ipset_session_full_io(struct ipset_session *session,
			  const char *filename,
			  enum ipset_io_type what)
.sp
int ipset_session_normal_io(struct ipset_session *session,
			    const char *filename,
			    enum ipset_io_type what)
.sp
FILE * ipset_session_io_stream(struct ipset_session *session,
			       enum ipset_io_type what)
.sp
int ipset_session_io_close(struct ipset_session *session,
			   enum ipset_io_type what)
.SH DESCRIPTION
libipset provides a library interface to 
.BR ipset(8). 
The integer return valued functions return 0 on success and a negative
value on failure.
.TP 
ipset_load_types
Loads in the supported ipset types in the library and make them
available for the ipset interface.

.TP
ipset_init
Initializes the ipset interface: allocates and initializes the required
internal structures, opens up the netlink channel. The function returns
the library interface structure of type
.B
struct ipset *
or
.B NULL
on failure.

.TP
ipset_parse_argv
Parses the
.B argc
length of array of strings
.B argv 
with the already initialized
.B
ipset
library structure.
If the command is successfully parsed, it is then submitted to the kernel
to execute. In the case of error, the textual error message is printed
and a negative number is returned.

.TP
ipset_parse_line
Parses the string
.B line
with the already initialized
.B
ipset
library structure. The line is supposed to contain
a single ipset command in restore format. If the command is successfully
parsed, it is then submitted to the kernel to execute. In the case of
error, the textual error message is printed and a negative number is
returned. 

.TP
ipset_parse_stream
Parses the stream
.B f
with the already initialized
.B
ipset
library structure. The stream may contain multiple newline
separated ipset commands in restore format. The commands are parsed
and then submitted to the kernel in batches for efficiecy. In the case of
error, the textual error message is printed and a negative number is
returned. 

.TP
ipset_fini
Closes the netlink channel, closes opened streams and releases allocated
structures holding by the
.B ipset
library structure. 

.PP
The following functions makes possible to customize the interface.
.TP
ipset_custom_printf
Sets or resets the print functions for the
.B
ipset
library structure, where
.B
custom_error
is the custom error print function for the internal library errors,
.B
standard_error
is the print function for the netlink/kernel related errors and
.B
outfn
is the output function to print the result of list/save commands.
The
.B
p
pointer makes possible to pass arbitrary structure to the custom
print functions. If
.B
NULL
is passed instead of a function pointer, the default print function
is set for the given task. If any of the print functions is non-default,
then the
.I
version,
.I
help,
.I
interactive
ipset commands are ignored.

.TP
ipset_session
The function returns the session structure
of the
.B
ipset
library structure, in order to manipulate the IO parameters.

.TP
ipset_session_full_io
You can control the full IO, i.e. input (restore) and output (save)
separatedly by the function. The
.B
session
parameter is the session structure of the library interface,
.B
filename
is the filename you want to use for input or output
and
.B
what
tells the function you want to set input or output file.
If there's an already opened file for the given IO mode, it is closed.
The function returns an error if normal mode is in use. If
.B
NULL
is passed instead of a filename, already opened file is closed
and the normal stream is set for the given IO mode (stdin for input,
stdout for output). Input/output files can be set separatedly.

.TP
ipset_session_normal_io
You can control the normal IO, which corresponds to the interface
provided by
.B
ipset(8)
itself.
.B
session
parameter is the session structure of the library interface,
.B
filename
is the filename you want to use for input or output
and
.B
what
tells the function you want to set input or output file.
If there's an already opened file for input/output, it is closed.
The function returns an error if full mode is in use. If
.B
NULL
is passed instead of a filename, already opened file is closed
and the normal stream is set for the given IO mode (stdin for input,
stdout for output). Input/output files cannot be set separatedly.

.TP
ipset_session_io_stream
The function returns the stream set for the
.B
session
where
.B
what
tells the function you want to get the input or the output stream.

.TP
ipset_session_io_close
The function closes the stream for the
.B
session
where
.B
what
tells the function you want to close the input or the output
stream. After closing, the standard streams are set: stdin for input,
stdout for output.

.SH AUTHORS
ipset/libipset was designed and written by Jozsef Kadlecsik.

.SH SEE ALSO
.BR ipset(8),
.br
/usr/include/libipset/ipset.h
/usr/include/libipset/session.h