freebsd-skq/usr.bin/rpcgen/rpcgen.1
Dimitry Andric 0dac0ed841 Let rpcgen(1) support an environment variable RPCGEN_CPP to find the C
preprocessor to run.  Previously, it always ran /usr/bin/cpp, unless you
used the -Y option, and even then you could not set the basename.  It
also attempted to run /usr/ccs/lib/cpp for SVR4 compatibility, but this
is obsolete, and has been removed.

Note that setting RPCGEN_CPP to a command with arguments is supported,
though the command line parsing is simplistic.  However, setting it to
e.g. "gcc46 -E" or "clang -E" will lead to problems, because both gcc
and clang in -E mode will consider files with unknown extensions (such
as .x) as object files, and attempt to link them.

This could be worked around by also adding "-x c", but it is much safer
to set RPCGEN_CPP to e.g. "cpp46" or "clang-cpp" instead.

MFC after:	1 week
2012-02-06 12:03:21 +00:00

538 lines
11 KiB
Groff

.\" @(#)rpcgen.1 1.35 93/06/02 SMI
.\" $FreeBSD$
.\" Copyright 1985-1993 Sun Microsystems, Inc.
.\"
.Dd September 2, 2005
.Dt RPCGEN 1
.Os
.Sh NAME
.Nm rpcgen
.Nd an RPC protocol compiler
.Sh SYNOPSIS
.Nm
.Ar infile
.Nm
.Op Fl a
.Op Fl b
.Op Fl C
.Oo
.Fl D Ns Ar name Ns Op Ar =value
.Oc
.Op Fl i Ar size
.Op Fl I Fl P Op Fl K Ar seconds
.Op Fl L
.Op Fl M
.Op Fl N
.Op Fl T
.Op Fl Y Ar pathname
.Ar infile
.Nm
.Oo
.Fl c |
.Fl h |
.Fl l |
.Fl m |
.Fl t |
.Fl \&Sc |
.Fl \&Ss |
.Fl \&Sm
.Oc
.Op Fl o Ar outfile
.Op Ar infile
.Nm
.Op Fl s Ar nettype
.Op Fl o Ar outfile
.Op Ar infile
.Nm
.Op Fl n Ar netid
.Op Fl o Ar outfile
.Op Ar infile
.\" .SH AVAILABILITY
.\" .LP
.\" SUNWcsu
.Sh DESCRIPTION
The
.Nm
utility is a tool that generates C code to implement an
.Tn RPC
protocol.
The input to
.Nm
is a language similar to C known as
.Tn RPC
Language (Remote Procedure Call Language).
.Pp
The
.Nm
utility is normally used as in the first synopsis where
it takes an input file and generates three output files.
If the
.Ar infile
is named
.Pa proto.x ,
then
.Nm
generates a header in
.Pa proto.h ,
XDR routines in
.Pa proto_xdr.c ,
server-side stubs in
.Pa proto_svc.c ,
and client-side stubs in
.Pa proto_clnt.c .
With the
.Fl T
option,
it also generates the
.Tn RPC
dispatch table in
.Pa proto_tbl.i .
.Pp
The
.Nm
utility can also generate sample client and server files
that can be customized to suit a particular application.
The
.Fl \&Sc ,
.Fl \&Ss
and
.Fl \&Sm
options generate sample client, server and makefile, respectively.
The
.Fl a
option generates all files, including sample files.
If the
.Ar infile
is
.Pa proto.x ,
then the client side sample file is written to
.Pa proto_client.c ,
the server side sample file to
.Pa proto_server.c
and the sample makefile to
.Pa makefile.proto .
.Pp
If option
.Fl I
is set,
the server created can be started both by the port monitors
(for example,
.Xr inetd 8 )
or by itself.
When it is started by a port monitor,
it creates servers only for the transport for which
the file descriptor
.Em 0
was passed.
The name of the transport may be specified
by setting up the environment variable
.Ev NLSPROVIDER .
When the server generated by
.Nm
is executed,
it creates server handles for all the transports
specified in
.Ev NETPATH
environment variable,
or if it is unset,
it creates server handles for all the visible transports from
.Pa /etc/netconfig
file.
Note:
the transports are chosen at run time and not at compile time.
When the server is self-started,
it backgrounds itself by default.
A special define symbol
.Em RPC_SVC_FG
can be used to run the server process in foreground.
.Pp
The second synopsis provides special features which allow
for the creation of more sophisticated
.Tn RPC
servers.
These features include support for user provided
.Em #defines
and
.Tn RPC
dispatch tables.
The entries in the
.Tn RPC
dispatch table contain:
.Bl -bullet -offset indent -compact
.It
pointers to the service routine corresponding to that procedure,
.It
a pointer to the input and output arguments,
.It
the size of these routines.
.El
A server can use the dispatch table to check authorization
and then to execute the service routine;
a client library may use it to deal with the details of storage
management and XDR data conversion.
.Pp
The other three synopses shown above are used when
one does not want to generate all the output files,
but only a particular one.
See the
.Sx EXAMPLES
section below for examples of
.Nm
usage.
When
.Nm
is executed with the
.Fl s
option,
it creates servers for that particular class of transports.
When
executed with the
.Fl n
option,
it creates a server for the transport specified by
.Ar netid .
If
.Ar infile
is not specified,
.Nm
accepts the standard input.
.Pp
The C preprocessor,
.Em cc -E
is run on the input file before it is actually interpreted by
.Nm .
For each type of output file,
.Nm
defines a special preprocessor symbol for use by the
.Nm
programmer:
.Bl -tag -width indent
.It RPC_HDR
defined when compiling into headers
.It RPC_XDR
defined when compiling into XDR routines
.It RPC_SVC
defined when compiling into server-side stubs
.It RPC_CLNT
defined when compiling into client-side stubs
.It RPC_TBL
defined when compiling into RPC dispatch tables
.El
.Pp
Any line beginning with
.Dq %
is passed directly into the output file,
uninterpreted by
.Nm .
To specify the path name of the C preprocessor use
.Fl Y
flag.
.Pp
For every data type referred to in
.Ar infile ,
.Nm
assumes that there exists a
routine with the string
.Em xdr_
prepended to the name of the data type.
If this routine does not exist in the
.Tn RPC/XDR
library, it must be provided.
Providing an undefined data type
allows customization of
.Xr xdr 3
routines.
.Sh OPTIONS
The following options are available:
.Bl -tag -width indent
.It Fl a
Generate all files, including sample files.
.It Fl b
Backward compatibility mode.
Generate transport specific
.Tn RPC
code for older versions
of the operating system.
.It Fl c
Compile into
.Tn XDR
routines.
.It Fl C
Generate ANSI C code.
This is always done, the flag is only provided for backwards compatibility.
.It Fl D Ns Ar name
.It Fl D Ns Ar name=value
.\".It Fl D Ns Ar name Ns Op Ar =value
Define a symbol
.Ar name .
Equivalent to the
.Em #define
directive in the source.
If no
.Ar value
is given,
.Ar value
is defined as
.Em 1 .
This option may be specified more than once.
.It Fl h
Compile into C data-definitions (a header).
.Fl T
option can be used in conjunction to produce a
header which supports
.Tn RPC
dispatch tables.
.It Fl i Ar size
Size at which to start generating inline code.
This option is useful for optimization.
The default size is 5.
.Pp
Note: in order to provide backwards compatibility with the older
.Nm
on the
.Fx
platform, the default is actually 0 (which means
that inline code generation is disabled by default).
You must specify
a non-zero value explicitly to override this default.
.It Fl I
Compile support for
.Xr inetd 8
in the server side stubs.
Such servers can be self-started or can be started by
.Xr inetd 8 .
When the server is self-started, it backgrounds itself by default.
A special define symbol
.Em RPC_SVC_FG
can be used to run the
server process in foreground, or the user may simply compile without
the
.Fl I
option.
.Pp
If there are no pending client requests, the
.Xr inetd 8
servers exit after 120 seconds (default).
The default can be changed with the
.Fl K
option.
All the error messages for
.Xr inetd 8
servers
are always logged with
.Xr syslog 3 .
.Pp
Note:
Contrary to some systems, in
.Fx
this option is needed to generate
servers that can be invoked through portmonitors and
.Xr inetd 8 .
.Pp
.It Fl K Ar seconds
By default, services created using
.Nm
and invoked through
port monitors wait 120 seconds
after servicing a request before exiting.
That interval can be changed using the
.Fl K
flag.
To create a server that exits immediately upon servicing a request,
use
.Fl K Ar 0 .
To create a server that never exits, the appropriate argument is
.Fl K Ar -1 .
.Pp
When monitoring for a server,
some portmonitors
.Em always
spawn a new process in response to a service request.
If it is known that a server will be used with such a monitor, the
server should exit immediately on completion.
For such servers,
.Nm
should be used with
.Fl K Ar 0 .
.It Fl l
Compile into client-side stubs.
.It Fl L
When the servers are started in foreground, use
.Xr syslog 3
to log the server errors instead of printing them on the standard
error.
.It Fl m
Compile into server-side stubs,
but do not generate a
.Qq main
routine.
This option is useful for doing callback-routines
and for users who need to write their own
.Qq main
routine to do initialization.
.It Fl M
Generate multithread-safe stubs for passing arguments and results between
rpcgen generated code and user written code.
This option is useful
for users who want to use threads in their code.
However, the
.Xr rpc_svc_calls 3
functions are not yet MT-safe, which means that rpcgen generated server-side
code will not be MT-safe.
.It Fl N
Allow procedures to have multiple arguments.
It also uses the style of parameter passing that closely resembles C.
So, when passing an argument to a remote procedure, you do not have to
pass a pointer to the argument, but can pass the argument itself.
This behavior is different from the old style of
.Nm
generated code.
To maintain backward compatibility,
this option is not the default.
.It Fl n Ar netid
Compile into server-side stubs for the transport
specified by
.Ar netid .
There should be an entry for
.Ar netid
in the
netconfig database.
This option may be specified more than once,
so as to compile a server that serves multiple transports.
.It Fl o Ar outfile
Specify the name of the output file.
If none is specified,
standard output is used
.Fl ( c ,
.Fl h ,
.Fl l ,
.Fl m ,
.Fl n ,
.Fl s ,
.Fl \&Sc ,
.Fl \&Sm ,
.Fl \&Ss ,
and
.Fl t
modes only).
.It Fl P
Compile support for
port monitors
in the server side stubs.
.Pp
Note:
Contrary to some systems, in
.Fx
this option is needed to generate
servers that can be monitored.
.Pp
If the
.Fl I
option has been specified,
.Fl P
is turned off automatically.
.It Fl s Ar nettype
Compile into server-side stubs for all the
transports belonging to the class
.Ar nettype .
The supported classes are
.Em netpath ,
.Em visible ,
.Em circuit_n ,
.Em circuit_v ,
.Em datagram_n ,
.Em datagram_v ,
.Em tcp ,
and
.Em udp
(see
.Xr rpc 3
for the meanings associated with these classes).
This option may be specified more than once.
Note:
the transports are chosen at run time and not at compile time.
.It Fl \&Sc
Generate sample client code that uses remote procedure calls.
.It Fl \&Sm
Generate a sample
.Pa Makefile
which can be used for compiling the application.
.It Fl \&Ss
Generate sample server code that uses remote procedure calls.
.It Fl t
Compile into
.Tn RPC
dispatch table.
.It Fl T
Generate the code to support
.Tn RPC
dispatch tables.
.Pp
The options
.Fl c ,
.Fl h ,
.Fl l ,
.Fl m ,
.Fl s ,
.Fl \&Sc ,
.Fl \&Sm ,
.Fl \&Ss ,
and
.Fl t
are used exclusively to generate a particular type of file,
while the options
.Fl D
and
.Fl T
are global and can be used with the other options.
.It Fl Y Ar pathname
Give the name of the directory where
.Nm
will start looking for the C-preprocessor.
.El
.Sh ENVIRONMENT
If the
.Ev RPCGEN_CPP
environment variable is set, its value is used as the command line of the
C preprocessor to be run on the input file.
.Sh EXAMPLES
The following example:
.Dl example% rpcgen -T prot.x
.Pp
generates all the five files:
.Pa prot.h ,
.Pa prot_clnt.c ,
.Pa prot_svc.c ,
.Pa prot_xdr.c
and
.Pa prot_tbl.i .
.Pp
The following example sends the C data-definitions (header)
to the standard output.
.Dl example% rpcgen -h prot.x
.Pp
To send the test version of the
.Fl D Ns Ar TEST ,
server side stubs for
all the transport belonging to the class
.Ar datagram_n
to standard output, use:
.Dl example% rpcgen -s datagram_n -DTEST prot.x
.Pp
To create the server side stubs for the transport indicated
by
.Ar netid
tcp,
use:
.Dl example% rpcgen -n tcp -o prot_svc.c prot.x
.Sh SEE ALSO
.Xr cc 1 ,
.Xr rpc 3 ,
.Xr rpc_svc_calls 3 ,
.Xr syslog 3 ,
.Xr xdr 3 ,
.Xr inetd 8
.Rs
.%T The rpcgen chapter in the NETP manual
.Re