remote_generator.pl

#!/usr/bin/perl -w
#
# This script parses remote_protocol.x or qemu_protocol.x and produces lots of
# boilerplate code for both ends of the remote connection.
#
# The first non-option argument specifies the prefix to be searched for, and
# output to, the boilerplate code.  The second non-option argument is the
# file you want to operate on.  For instance, to generate the dispatch table
# for both remote_protocol.x and qemu_protocol.x, you would run the
# following:
#
# remote_generator.pl -c -t remote ../src/remote/remote_protocol.x
# remote_generator.pl -t qemu ../src/remote/qemu_protocol.x
#
# By Richard Jones <rjones@redhat.com>

use strict;

use Getopt::Std;

# Command line options.
our ($opt_p, $opt_t, $opt_a, $opt_r, $opt_d, $opt_c);
getopts ('ptardc');

my $structprefix = $ARGV[0];
my $procprefix = uc $structprefix;
shift;

# Convert name_of_call to NameOfCall.
sub name_to_ProcName {
    my $name = shift;
    my @elems = split /_/, $name;
    @elems = map ucfirst, @elems;
    join "", @elems
}

# Read the input file (usually remote_protocol.x) and form an
# opinion about the name, args and return type of each RPC.
my ($name, $ProcName, $id, %calls, @calls);

# only generate a close method if -c was passed
if ($opt_c) {
    # REMOTE_PROC_CLOSE has no args or ret.
    $calls{close} = {
        name => "close",
        ProcName => "Close",
        UC_NAME => "CLOSE",
        args => "void",
        ret => "void",
    };
}

while (<>) {
    if (/^struct ${structprefix}_(.*)_args/) {
        $name = $1;
        $ProcName = name_to_ProcName ($name);

        die "duplicate definition of ${structprefix}_${name}_args"
            if exists $calls{$name};

        $calls{$name} = {
            name => $name,
            ProcName => $ProcName,
            UC_NAME => uc $name,
            args => "${structprefix}_${name}_args",
            ret => "void",
        };

    } elsif (/^struct ${structprefix}_(.*)_ret/) {
        $name = $1;
        $ProcName = name_to_ProcName ($name);

        if (exists $calls{$name}) {
            $calls{$name}->{ret} = "${structprefix}_${name}_ret";
        } else {
            $calls{$name} = {
                name => $name,
                ProcName => $ProcName,
                UC_NAME => uc $name,
                args => "void",
                ret => "${structprefix}_${name}_ret"
            }
        }
    } elsif (/^struct ${structprefix}_(.*)_msg/) {
        $name = $1;
        $ProcName = name_to_ProcName ($name);

        $calls{$name} = {
            name => $name,
            ProcName => $ProcName,
            UC_NAME => uc $name,
            msg => "${structprefix}_${name}_msg"
        }
    } elsif (/^\s*${procprefix}_PROC_(.*?)\s+=\s+(\d+),?$/) {
        $name = lc $1;
        $id = $2;
        $ProcName = name_to_ProcName ($name);

        $calls[$id] = $calls{$name};
    }
}

#----------------------------------------------------------------------
# Output

print <<__EOF__;
/* Automatically generated by remote_generator.pl.
 * Do not edit this file.  Any changes you make will be lost.
 */

__EOF__

# Debugging.
if ($opt_d) {
    my @keys = sort (keys %calls);
    foreach (@keys) {
        print "$_:\n";
        print "        name $calls{$_}->{name} ($calls{$_}->{ProcName})\n";
        print "        $calls{$_}->{args} -> $calls{$_}->{ret}\n";
    }
}

# Prototypes for dispatch functions ("remote_dispatch_prototypes.h").
elsif ($opt_p) {
    my @keys = sort (keys %calls);
    foreach (@keys) {
        # Skip things which are REMOTE_MESSAGE
        next if $calls{$_}->{msg};

        print "static int ${structprefix}Dispatch$calls{$_}->{ProcName}(\n";
        print "    struct qemud_server *server,\n";
        print "    struct qemud_client *client,\n";
        print "    virConnectPtr conn,\n";
        print "    remote_message_header *hdr,\n";
        print "    remote_error *rerr,\n";
        print "    $calls{$_}->{args} *args,\n";
        print "    $calls{$_}->{ret} *ret);\n";
    }
}

# Union of all arg types
# ("remote_dispatch_args.h").
elsif ($opt_a) {
    for ($id = 0 ; $id <= $#calls ; $id++) {
        if (defined $calls[$id] &&
            !$calls[$id]->{msg} &&
            $calls[$id]->{args} ne "void") {
            print "    $calls[$id]->{args} val_$calls[$id]->{args};\n";
        }
    }
}

# Union of all arg types
# ("remote_dispatch_ret.h").
elsif ($opt_r) {
    for ($id = 0 ; $id <= $#calls ; $id++) {
        if (defined $calls[$id] &&
            !$calls[$id]->{msg} &&
            $calls[$id]->{ret} ne "void") {
            print "    $calls[$id]->{ret} val_$calls[$id]->{ret};\n";
        }
    }
}

# Inside the switch statement, prepare the 'fn', 'args_filter', etc
# ("remote_dispatch_table.h").
elsif ($opt_t) {
    for ($id = 0 ; $id <= $#calls ; $id++) {
        if (defined $calls[$id] && !$calls[$id]->{msg}) {
            print "{   /* $calls[$id]->{ProcName} => $id */\n";
            print "    .fn = (dispatch_fn) ${structprefix}Dispatch$calls[$id]->{ProcName},\n";
            if ($calls[$id]->{args} ne "void") {
                print "    .args_filter = (xdrproc_t) xdr_$calls[$id]->{args},\n";
            } else {
                print "    .args_filter = (xdrproc_t) xdr_void,\n";
            }
            if ($calls[$id]->{ret} ne "void") {
                print "    .ret_filter = (xdrproc_t) xdr_$calls[$id]->{ret},\n";
            } else {
                print "    .ret_filter = (xdrproc_t) xdr_void,\n";
            }
            print "},\n";
        } else {
            if ($calls[$id]->{msg}) {
                print "{   /* Async event $calls[$id]->{ProcName} => $id */\n";
            } else {
                print "{   /* (unused) => $id */\n";
            }
            print "    .fn = NULL,\n";
            print "    .args_filter = (xdrproc_t) xdr_void,\n";
            print "    .ret_filter = (xdrproc_t) xdr_void,\n";
            print "},\n";
        }
    }
}