usr/src/sys/kern/vnode_if.sh

#!/bin/sh -
#
# Copyright (c) 1992, 1993
#       The Regents of the University of California.  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.
# 3. All advertising materials mentioning features or use of this software
#    must display the following acknowledgement:
#       This product includes software developed by the University of
#       California, Berkeley and its contributors.
# 4. Neither the name of the University nor the names of its contributors
#    may be used to endorse or promote products derived from this software
#    without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
#
#       @(#)vnode_if.sh 8.1 (Berkeley) 6/10/93
#

# Script to produce VFS front-end sugar.
#
# usage: vnode_if.sh srcfile
#       (where srcfile is currently /sys/kern/vnode_if.src)
#
# These awk scripts are not particularly well written, specifically they
# don't use arrays well and figure out the same information repeatedly.
# Please rewrite them if you actually understand how to use awk.  Note,
# they use nawk extensions and gawk's toupper.

if [ $# -ne 1 ] ; then
        echo 'usage: vnode_if.sh srcfile'
        exit 1
fi

# Name of the source file.
SRC=$1

# Names of the created files.
CFILE=vnode_if.c
HEADER=vnode_if.h

# Awk program (must support nawk extensions and gawk's "toupper")
# Use "awk" at Berkeley, "gawk" elsewhere.
AWK=awk

# Print out header information for vnode_if.h.
cat << END_OF_LEADING_COMMENT > $HEADER
/*
 * This file is produced automatically.
 * Do not modify anything in here by hand.
 *
 * Created from @(#)vnode_if.sh 8.1 (Berkeley) 6/10/93
 */

extern struct vnodeop_desc vop_default_desc;
END_OF_LEADING_COMMENT

# Awk script to take vnode_if.src and turn it into vnode_if.h.
$AWK '
        NF == 0 || $0 ~ "^#" {
                next;
        }
        {
                # Get the function name.
                name = $1;
                uname = toupper(name);

                # Get the function arguments.
                for (c1 = 0;; ++c1) {
                        if (getline <= 0)
                                exit
                        if ($0 ~ "^};")
                                break;
                        a[c1] = $0;
                }

                # Print out the vop_F_args structure.
                printf("struct %s_args {\n\tstruct vnodeop_desc *a_desc;\n",
                    name);
                for (c2 = 0; c2 < c1; ++c2) {
                        c3 = split(a[c2], t);
                        printf("\t");
                        if (t[2] ~ "WILLRELE")
                                c4 = 3;
                        else
                                c4 = 2;
                        for (; c4 < c3; ++c4)
                                printf("%s ", t[c4]);
                        beg = match(t[c3], "[^*]");
                        printf("%sa_%s\n",
                            substr(t[c4], 0, beg - 1), substr(t[c4], beg));
                }
                printf("};\n");

                # Print out extern declaration.
                printf("extern struct vnodeop_desc %s_desc;\n", name);

                # Print out inline struct.
                printf("static inline int %s(", uname);
                sep = ", ";
                for (c2 = 0; c2 < c1; ++c2) {
                        if (c2 == c1 - 1)
                                sep = ")\n";
                        c3 = split(a[c2], t);
                        beg = match(t[c3], "[^*]");
                        end = match(t[c3], ";");
                        printf("%s%s", substr(t[c3], beg, end - beg), sep);
                }
                for (c2 = 0; c2 < c1; ++c2) {
                        c3 = split(a[c2], t);
                        printf("\t");
                        if (t[2] ~ "WILLRELE")
                                c4 = 3;
                        else
                                c4 = 2;
                        for (; c4 < c3; ++c4)
                                printf("%s ", t[c4]);
                        beg = match(t[c3], "[^*]");
                        printf("%s%s\n",
                            substr(t[c4], 0, beg - 1), substr(t[c4], beg));
                }
                printf("{\n\tstruct %s_args a;\n\n", name);
                printf("\ta.a_desc = VDESC(%s);\n", name);
                for (c2 = 0; c2 < c1; ++c2) {
                        c3 = split(a[c2], t);
                        printf("\t");
                        beg = match(t[c3], "[^*]");
                        end = match(t[c3], ";");
                        printf("a.a_%s = %s\n",
                            substr(t[c3], beg, end - beg), substr(t[c3], beg));
                }
                c1 = split(a[0], t);
                beg = match(t[c1], "[^*]");
                end = match(t[c1], ";");
                printf("\treturn (VCALL(%s, VOFFSET(%s), &a));\n}\n",
                    substr(t[c1], beg, end - beg), name);
        }' < $SRC >> $HEADER

# Print out header information for vnode_if.c.
cat << END_OF_LEADING_COMMENT > $CFILE
/*
 * This file is produced automatically.
 * Do not modify anything in here by hand.
 *
 * Created from @(#)vnode_if.sh 8.1 (Berkeley) 6/10/93
 */

#include <sys/param.h>
#include <sys/mount.h>
#include <sys/vnode.h>

struct vnodeop_desc vop_default_desc = {
        0,
        "default",
        0,
        NULL,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        NULL,
};

END_OF_LEADING_COMMENT

# Awk script to take vnode_if.src and turn it into vnode_if.c.
$AWK 'function kill_surrounding_ws (s) {
                sub (/^[ \t]*/, "", s);
                sub (/[ \t]*$/, "", s);
                return s;
        }

        function read_args() {
                numargs = 0;
                while (getline ln) {
                        if (ln ~ /}/) {
                                break;
                        };

                        # Delete comments, if any.
                        gsub (/\/\*.*\*\//, "", ln);

                        # Delete leading/trailing space.
                        ln = kill_surrounding_ws(ln);

                        # Pick off direction.
                        if (1 == sub(/^INOUT[ \t]+/, "", ln))
                                dir = "INOUT";
                        else if (1 == sub(/^IN[ \t]+/, "", ln))
                                dir = "IN";
                        else if (1 == sub(/^OUT[ \t]+/, "", ln))
                                dir = "OUT";
                        else
                                bail("No IN/OUT direction for \"" ln "\".");

                        # check for "WILLRELE"
                        if (1 == sub(/^WILLRELE[ \t]+/, "", ln)) {
                                rele = "WILLRELE";
                        } else {
                                rele = "WONTRELE";
                        };

                        # kill trailing ;
                        if (1 != sub (/;$/, "", ln)) {
                                bail("Missing end-of-line ; in \"" ln "\".");
                        };

                        # pick off variable name
                        if (!(i = match(ln, /[A-Za-z0-9_]+$/))) {
                                bail("Missing var name \"a_foo\" in \"" ln "\".");
                        };
                        arg = substr (ln, i);
                        # Want to <<substr(ln, i) = "";>>, but nawk cannot.
                        # Hack around this.
                        ln = substr(ln, 1, i-1);

                        # what is left must be type
                        # (put clean it up some)
                        type = ln;
                        gsub (/[ \t]+/, " ", type);   # condense whitespace
                        type = kill_surrounding_ws(type);

                        # (boy this was easier in Perl)

                        numargs++;
                        dirs[numargs] = dir;
                        reles[numargs] = rele;
                        types[numargs] = type;
                        args[numargs] = arg;
                };
        }

        function generate_operation_vp_offsets() {
                printf ("int %s_vp_offsets[] = {\n", name);
                # as a side effect, figure out the releflags
                releflags = "";
                vpnum = 0;
                for (i=1; i<=numargs; i++) {
                        if (types[i] == "struct vnode *") {
                                printf ("\tVOPARG_OFFSETOF(struct %s_args,a_%s),\n",
                                        name, args[i]);
                                if (reles[i] == "WILLRELE") {
                                        releflags = releflags "|VDESC_VP" vpnum "_WILLRELE";
                                };
                                vpnum++;
                        };
                };
                sub (/^\|/, "", releflags);
                print "\tVDESC_NO_OFFSET";
                print "};";
        }

        function find_arg_with_type (type) {
                for (i=1; i<=numargs; i++) {
                        if (types[i] == type) {
                                return "VOPARG_OFFSETOF(struct " name "_args,a_" args[i] ")";
                        };
                };
                return "VDESC_NO_OFFSET";
        }

        function generate_operation_desc() {
                printf ("struct vnodeop_desc %s_desc = {\n", name);
                # offset
                printf ("\t0,\n");
                # printable name
                printf ("\t\"%s\",\n", name);
                # flags
                vppwillrele = "";
                for (i=1; i<=numargs; i++) {
                        if (types[i] == "struct vnode **" &&
                                (reles[i] == "WILLRELE")) {
                                vppwillrele = "|VDESC_VPP_WILLRELE";
                        };
                };
                if (releflags == "") {
                        printf ("\t0%s,\n", vppwillrele);
                } else {
                        printf ("\t%s%s,\n", releflags, vppwillrele);
                };
                # vp offsets
                printf ("\t%s_vp_offsets,\n", name);
                # vpp (if any)
                printf ("\t%s,\n", find_arg_with_type("struct vnode **"));
                # cred (if any)
                printf ("\t%s,\n", find_arg_with_type("struct ucred *"));
                # proc (if any)
                printf ("\t%s,\n", find_arg_with_type("struct proc *"));
                # componentname
                printf ("\t%s,\n", find_arg_with_type("struct componentname *"));
                # transport layer information
                printf ("\tNULL,\n};\n");
        }

        NF == 0 || $0 ~ "^#" {
                next;
        }
        {
                # get the function name
                name = $1;

                # get the function arguments
                read_args();

                # Print out the vop_F_vp_offsets structure.  This all depends
                # on naming conventions and nothing else.
                generate_operation_vp_offsets();

                # Print out the vnodeop_desc structure.
                generate_operation_desc();

                printf "\n";

        }' < $SRC >> $CFILE
# THINGS THAT DON'T WORK RIGHT YET.
#
# Two existing BSD vnodeops (bwrite and strategy) don't take any vnodes as
# arguments.  This means that these operations can't function successfully
# through a bypass routine.
#
# Bwrite and strategy will be replaced when the VM page/buffer cache
# integration happens.
#
# To get around this problem for now we handle these ops as special cases.

cat << END_OF_SPECIAL_CASES >> $HEADER
#include <sys/buf.h>
struct vop_strategy_args {
        struct vnodeop_desc *a_desc;
        struct buf *a_bp;
};
extern struct vnodeop_desc vop_strategy_desc;
static inline int VOP_STRATEGY(bp)
        struct buf *bp;
{
        struct vop_strategy_args a;

        a.a_desc = VDESC(vop_strategy);
        a.a_bp = bp;
        return (VCALL((bp)->b_vp, VOFFSET(vop_strategy), &a));
}

struct vop_bwrite_args {
        struct vnodeop_desc *a_desc;
        struct buf *a_bp;
};
extern struct vnodeop_desc vop_bwrite_desc;
static inline int VOP_BWRITE(bp)
        struct buf *bp;
{
        struct vop_bwrite_args a;

        a.a_desc = VDESC(vop_bwrite);
        a.a_bp = bp;
        return (VCALL((bp)->b_vp, VOFFSET(vop_bwrite), &a));
}
END_OF_SPECIAL_CASES

cat << END_OF_SPECIAL_CASES >> $CFILE
int vop_strategy_vp_offsets[] = {
        VDESC_NO_OFFSET
};
struct vnodeop_desc vop_strategy_desc = {
        0,
        "vop_strategy",
        0,
        vop_strategy_vp_offsets,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        NULL,
};
int vop_bwrite_vp_offsets[] = {
        VDESC_NO_OFFSET
};
struct vnodeop_desc vop_bwrite_desc = {
        0,
        "vop_bwrite",
        0,
        vop_bwrite_vp_offsets,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        VDESC_NO_OFFSET,
        NULL,
};
END_OF_SPECIAL_CASES

# Add the vfs_op_descs array to the C file.
$AWK '
        BEGIN {
                printf("\nstruct vnodeop_desc *vfs_op_descs[] = {\n");
                printf("\t&vop_default_desc,    /* MUST BE FIRST */\n");
                printf("\t&vop_strategy_desc,   /* XXX: SPECIAL CASE */\n");
                printf("\t&vop_bwrite_desc,     /* XXX: SPECIAL CASE */\n");
        }
        END {
                printf("\tNULL\n};\n");
        }
        NF == 0 || $0 ~ "^#" {
                next;
        }
        {
                # Get the function name.
                printf("\t&%s_desc,\n", $1);

                # Skip the function arguments.
                for (;;) {
                        if (getline <= 0)
                                exit
                        if ($0 ~ "^};")
                                break;
                }
        }' < $SRC >> $CFILE