libsyscall/create-syscalls.pl

   1 #!/usr/bin/perl
   2 #
   3 # Copyright (c) 2006 Apple Computer, Inc. All rights reserved.
   4 #
   5 # @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   6 #
   7 # This file contains Original Code and/or Modifications of Original Code
   8 # as defined in and that are subject to the Apple Public Source License
   9 # Version 2.0 (the 'License'). You may not use this file except in
  10 # compliance with the License. Please obtain a copy of the License at
  11 # http://www.opensource.apple.com/apsl/ and read it before using this
  12 # file.
  13 #
  14 # The Original Code and all software distributed under the License are
  15 # distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16 # EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17 # INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18 # FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  19 # Please see the License for the specific language governing rights and
  20 # limitations under the License.
  21 #
  22 # @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  23 #
  24 ##########################################################################
  25 #
  26 # % create-syscalls.pl syscalls.master custom-directory out-directory
  27 #
  28 # This script fills the the out-directory with a Makefile.inc and *.s
  29 # files to create the double-underbar syscall stubs.  It reads the
  30 # syscall.master file to get the symbol names and number of arguments,
  31 # and whether Libsystem should automatically create the (non-double-underbar)
  32 # stubs if Libc doesn't provide a wrapper.  Which system calls will get
  33 # the automatic treatment is writen to the libsyscall.list file, also
  34 # written to the out-directory.
  35 #
  36 # The custom-directory contains:
  37 # 1. SYS.h - used by the automatically created *.s and custom files
  38 # 2. custom.s - contains architecture specific additional system calls and
  39 #    auxilliary routines (like cerror)
  40 # 3. special case double-underbar stub files - which are copied into
  41 #    the out-directory
  42 #
  43 # The BSDmakefile copies /usr/include/architecture/ppc/emode_independent_asm.h
  44 # and /usr/include/architecture/i386/asm_help.h to $(OBJDIR)/include,
  45 # replacing .globl with .private_extern.  These headers, along with SYS.h
  46 # make the double-underbar syscall stub private_extern, so that then become
  47 # static in the resulting libSystem.dylib.
  48 #
  49 ##########################################################################
  50
  51 use strict;
  52 use File::Basename ();
  53 use File::Copy ();
  54 use File::Spec;
  55 use IO::File;
  56
  57 my $MyName = File::Basename::basename($0);
  58
  59 my @CustomSrc = qw(custom.s);
  60
  61 my @Copy = (qw(SYS.h), @CustomSrc);
  62 my $CustomDir;
  63 my %NoStub;
  64 my $OutDir;
  65 my %Stub = (
  66     quota => [4, 0],    # unimplemented
  67     setquota => [2, 0], # unimplemented
  68     syscall => [0, 0],  # custom/__syscall.s will be used
  69 );
  70 my $StubFile = 'libsyscall.list';
  71 # size in bytes of known types (only used for i386)
  72 my %TypeBytes = (
  73     'au_asid_t'         => 4,
  74     'caddr_t'           => 4,
  75     'gid_t'             => 4,
  76     'id_t'              => 4,
  77     'idtype_t'          => 4,
  78     'int'               => 4,
  79     'int32_t'           => 4,
  80     'int64_t'           => 8,
  81     'key_t'             => 4,
  82     'long'              => 4,
  83     'mach_port_name_t'  => 4,
  84     'mode_t'            => 4,
  85     'off_t'             => 8,
  86     'pid_t'             => 4,
  87     'semun_t'           => 4,
  88     'sigset_t'          => 4,
  89     'size_t'            => 4,
  90     'socklen_t'         => 4,
  91     'ssize_t'           => 4,
  92     'u_int'             => 4,
  93     'u_long'            => 4,
  94     'uid_t'             => 4,
  95     'uint32_t'          => 4,
  96     'uint64_t'          => 8,
  97     'user_addr_t'       => 4,
  98     'user_long_t'       => 4,
  99     'user_size_t'       => 4,
 100     'user_ssize_t'      => 4,
 101     'user_ulong_t'      => 4,
 102 );
 103
 104 ##########################################################################
 105 # Make a __xxx.s file: if it exists in the $CustomDir, just copy it, otherwise
 106 # create one.  We define the macro __SYSCALL_32BIT_ARG_BYTES so that SYS.h could
 107 # use that to define __SYSCALL dependent on the arguments' total size.
 108 ##########################################################################
 109 sub make_s {
 110     my($name, $args, $bytes) = @_;
 111     local $_;
 112     my $pseudo = $name;
 113     $pseudo = '__' . $pseudo unless $pseudo =~ /^__/;
 114     my $file = $pseudo . '.s';
 115     my $custom = File::Spec->join($CustomDir, $file);
 116     my $path = File::Spec->join($OutDir, $file);
 117     if(-f $custom) {
 118         File::Copy::copy($custom, $path) || die "$MyName: copy($custom, $path): $!\n";
 119         print "Copying $path\n";
 120     } else {
 121         my $f = IO::File->new($path, 'w');
 122         die "$MyName: $path: $!\n" unless defined($f);
 123         print $f "#define __SYSCALL_32BIT_ARG_BYTES $bytes\n\n";
 124         print $f "#include \"SYS.h\"\n\n";
 125         print $f "__SYSCALL($pseudo, $name, $args)\n";
 126         print "Creating $path\n";
 127     }
 128     return $file;
 129 }
 130
 131 sub usage {
 132     die "Usage: $MyName syscalls.master custom-directory out-directory\n";
 133 }
 134
 135 ##########################################################################
 136 # Read the syscall.master file and collect the system call names and number
 137 # of arguments.  It looks for the NO_SYSCALL_STUB quailifier following the
 138 # prototype to determine if no automatic stub should be created by Libsystem.
 139 # System call name that are already prefixed with double-underbar are set as
 140 # if the NO_SYSCALL_STUB qualifier were specified (whether it is or not).
 141 #
 142 # For the #if lines in syscall.master, all macros are assumed to be defined,
 143 # except COMPAT_GETFSSTAT (assumed undefined).
 144 ##########################################################################
 145 sub readmaster {
 146     my $file = shift;
 147     local $_;
 148     my $f = IO::File->new($file, 'r');
 149     die "$MyName: $file: $!\n" unless defined($f);
 150     my $line = 0;
 151     my $skip = 0;
 152     while(<$f>) {
 153         $line++;
 154         if(/^#\s*endif/) {
 155             $skip = 0;
 156             next;
 157         }
 158         if(/^#\s*else/) {
 159             $skip = -$skip;
 160             next;
 161         }
 162         chomp;
 163         if(/^#\s*if\s+(\S+)$/) {
 164             $skip = ($1 eq 'COMPAT_GETFSSTAT') ? -1 : 1;
 165             next;
 166         }
 167         next if $skip < 0;
 168         next unless /^\d/;
 169         s/^[^{]*{\s*//;
 170         s/\s*}.*$//; # }
 171         die "$MyName: no function prototype on line $line\n" unless length($_) > 0 && /;$/;
 172         my $no_syscall_stub = /\)\s*NO_SYSCALL_STUB\s*;/;
 173         my($name, $args) = /\s(\S+)\s*\(([^)]*)\)/;
 174         next if $name =~ /e?nosys/;
 175         $args =~ s/^\s+//;
 176         $args =~ s/\s+$//;
 177         my $argbytes = 0;
 178         my $nargs = 0;
 179         if($args ne '' && $args ne 'void') {
 180             my @a = split(',', $args);
 181             $nargs = scalar(@a);
 182             # Calculate the size of all the arguments (only used for i386)
 183             for my $type (@a) {
 184                 $type =~ s/\s*\w+$//; # remove the argument name
 185                 if($type =~ /\*$/) {
 186                     $argbytes += 4; # a pointer type
 187                 } else {
 188                     $type =~ s/^.*\s//; # remove any type qualifier, like unsigned
 189                     my $b = $TypeBytes{$type};
 190                     die "$MyName: $name: unknown type '$type'\n" unless defined($b);
 191                     $argbytes += $b;
 192                 }
 193             }
 194         }
 195         if($no_syscall_stub || $name =~ /^__/) {
 196             $NoStub{$name} = [$nargs, $argbytes];
 197         } else {
 198             $Stub{$name} = [$nargs, $argbytes];
 199         }
 200     }
 201 }
 202
 203 usage() unless scalar(@ARGV) == 3;
 204 $CustomDir = $ARGV[1];
 205 die "$MyName: $CustomDir: No such directory\n" unless -d $CustomDir;
 206 $OutDir = $ARGV[2];
 207 die "$MyName: $OutDir: No such directory\n" unless -d $OutDir;
 208
 209 readmaster($ARGV[0]);
 210
 211 ##########################################################################
 212 # copy the files specified in @Copy from the $CustomDir to $OutDir
 213 ##########################################################################
 214 for(@Copy) {
 215     my $custom = File::Spec->join($CustomDir, $_);
 216     my $path = File::Spec->join($OutDir, $_);
 217     File::Copy::copy($custom, $path) || die "$MyName: copy($custom, $path): $!\n";
 218 }
 219
 220 ##########################################################################
 221 # make all the *.s files
 222 ##########################################################################
 223 my @src;
 224 my($k, $v);
 225 while(($k, $v) = each(%Stub)) {
 226     push(@src, make_s($k, @$v));
 227 }
 228 while(($k, $v) = each(%NoStub)) {
 229     push(@src, make_s($k, @$v));
 230 }
 231
 232 ##########################################################################
 233 # create the Makefile.inc file from the list for files in @src and @CustomSrc
 234 ##########################################################################
 235 my $path = File::Spec->join($OutDir, 'Makefile.inc');
 236 my $f = IO::File->new($path, 'w');
 237 die "$MyName: $path: $!\n" unless defined($f);
 238 print $f ".PATH: $OutDir\n\n";
 239 print $f "SYSCALLSRCS= " . join(" \\\n\t", sort(@src, @CustomSrc)) . "\n\n";
 240 print $f "MDSRCS+= \$(SYSCALLSRCS)\n\n";
 241 print $f ".for S in \$(SYSCALLSRCS)\n";
 242 print $f "PRECFLAGS-\$(S)+= -I\$(OBJROOT)/include\n";
 243 print $f ".endfor\n";
 244 undef $f;
 245
 246 ##########################################################################
 247 # create the libsyscall.list file for Libsystem to use.  For the one that
 248 # should not have auto-generated stubs, the line begins with #.
 249 ##########################################################################
 250 $path = File::Spec->join($OutDir, $StubFile);
 251 $f = IO::File->new($path, 'w');
 252 die "$MyName: $path: $!\n" unless defined($f);
 253 # Add the %NoStub entries to %Stub, appending '#' to the name, so we can sort
 254 while(($k, $v) = each(%NoStub)) {
 255     $k =~ s/^__//;
 256     $Stub{"$k#"} = $v;
 257 }
 258 for(sort(keys(%Stub))) {
 259     $k = $_;
 260     if($k =~ s/#$//) {
 261         printf $f "#___%s\t%s\n", $k, $Stub{$_}->[0];
 262     } else {
 263         printf $f "___%s\t%s\n", $_, $Stub{$_}->[0];
 264     }
 265 }
 266 undef $f;