libsyscall/xcodescripts/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 ##########################################################################
  44
  45 use strict;
  46 use File::Basename ();
  47 use File::Copy ();
  48 use File::Spec;
  49 use IO::File;
  50
  51 my $MyName = File::Basename::basename($0);
  52
  53 my @CustomSrc = qw(custom.s);
  54
  55 my @Architectures = split /\s/, $ENV{"ARCHS"};
  56 my @Copy = (qw(SYS.h), @CustomSrc);
  57 my $CustomDir;
  58 my $PlatformsDir;
  59 my $PlatformName;
  60 my $OutDir;
  61 # size in bytes of known types (only used for i386)
  62 my %TypeBytes = (
  63     'au_asid_t'         => 4,
  64     'caddr_t'           => 4,
  65     'gid_t'             => 4,
  66     'id_t'              => 4,
  67     'idtype_t'          => 4,
  68     'int'               => 4,
  69     'int32_t'           => 4,
  70     'int64_t'           => 8,
  71     'key_t'             => 4,
  72     'long'              => 4,
  73     'mach_port_name_t'  => 4,
  74     'mode_t'            => 4,
  75     'off_t'             => 8,
  76     'pid_t'             => 4,
  77     'semun_t'           => 4,
  78     'sigset_t'          => 4,
  79     'size_t'            => 4,
  80     'socklen_t'         => 4,
  81     'ssize_t'           => 4,
  82     'u_int'             => 4,
  83     'u_long'            => 4,
  84     'uid_t'             => 4,
  85     'uint32_t'          => 4,
  86     'uint64_t'          => 8,
  87     'user_addr_t'       => 4,
  88     'user_long_t'       => 4,
  89     'user_size_t'       => 4,
  90     'user_ssize_t'      => 4,
  91     'user_ulong_t'      => 4,
  92 );
  93
  94 # Moving towards storing all data in this hash, then we always know
  95 # if data is aliased or not, or promoted or not.
  96 my %Symbols = (
  97     "quota" => {
  98         c_sym => "quota",
  99         syscall => "quota",
 100         asm_sym => "_quota",
 101         is_private => undef,
 102         is_custom => undef,
 103         nargs => 4,
 104         bytes => 0,
 105         aliases => {},
 106     },
 107     "setquota" => {
 108         c_sym => "setquota",
 109         syscall => "setquota",
 110         asm_sym => "_setquota",
 111         is_private => undef,
 112         is_custom => undef,
 113         nargs => 2,
 114         bytes => 0,
 115         aliases => {},
 116     },
 117     "syscall" => {
 118         c_sym => "syscall",
 119         syscall => "syscall",
 120         asm_sym => "_syscall",
 121         is_private => undef,
 122         is_custom => undef,
 123         nargs => 0,
 124         bytes => 0,
 125         aliases => {},
 126     },
 127 );
 128
 129 sub usage {
 130     die "Usage: $MyName syscalls.master custom-directory platforms-directory out-directory\n";
 131 }
 132
 133 ##########################################################################
 134 # Read the syscall.master file and collect the system call names and number
 135 # of arguments.  It looks for the NO_SYSCALL_STUB quailifier following the
 136 # prototype to determine if no automatic stub should be created by Libsystem.
 137 # System call name that are already prefixed with double-underbar are set as
 138 # if the NO_SYSCALL_STUB qualifier were specified (whether it is or not).
 139 #
 140 # For the #if lines in syscall.master, all macros are assumed to be defined,
 141 # except COMPAT_GETFSSTAT (assumed undefined).
 142 ##########################################################################
 143 sub readMaster {
 144     my $file = shift;
 145     local $_;
 146     my $f = IO::File->new($file, 'r');
 147     die "$MyName: $file: $!\n" unless defined($f);
 148     my $line = 0;
 149     my $skip = 0;
 150     while(<$f>) {
 151         $line++;
 152         if(/^#\s*endif/) {
 153             $skip = 0;
 154             next;
 155         }
 156         if(/^#\s*else/) {
 157             $skip = -$skip;
 158             next;
 159         }
 160         chomp;
 161         if(/^#\s*if\s+(\S+)$/) {
 162             $skip = ($1 eq 'COMPAT_GETFSSTAT') ? -1 : 1;
 163             next;
 164         }
 165         next if $skip < 0;
 166         next unless /^\d/;
 167         s/^[^{]*{\s*//;
 168         s/\s*}.*$//; # }
 169         die "$MyName: no function prototype on line $line\n" unless length($_) > 0 && /;$/;
 170         my $no_syscall_stub = /\)\s*NO_SYSCALL_STUB\s*;/;
 171         my($name, $args) = /\s(\S+)\s*\(([^)]*)\)/;
 172         next if $name =~ /e?nosys/;
 173         $args =~ s/^\s+//;
 174         $args =~ s/\s+$//;
 175         my $argbytes = 0;
 176         my $nargs = 0;
 177         if($args ne '' && $args ne 'void') {
 178             my @a = split(',', $args);
 179             $nargs = scalar(@a);
 180             # Calculate the size of all the arguments (only used for i386)
 181             for my $type (@a) {
 182                 $type =~ s/\s*\w+$//; # remove the argument name
 183                 if($type =~ /\*$/) {
 184                     $argbytes += 4; # a pointer type
 185                 } else {
 186                     $type =~ s/^.*\s//; # remove any type qualifier, like unsigned
 187                     my $b = $TypeBytes{$type};
 188                     die "$MyName: $name: unknown type '$type'\n" unless defined($b);
 189                     $argbytes += $b;
 190                 }
 191             }
 192         }
 193         $Symbols{$name} = {
 194             c_sym => $name,
 195             syscall => $name,
 196             asm_sym => $no_syscall_stub ? "___$name" : "_$name",
 197             is_private => $no_syscall_stub,
 198             is_custom => undef,
 199             nargs => $nargs,
 200             bytes => $argbytes,
 201             aliases => {},
 202             except => [],
 203         };
 204     }
 205 }
 206
 207 sub checkForCustomStubs {
 208     my ($dir) = @_;
 209
 210     my ($c_sym_name, $sym);
 211     while (($c_sym_name, $sym) = each %Symbols) {
 212         my $source = "__".$$sym{c_sym}.".s";
 213         my $custom = File::Spec->join($dir, $source);
 214         next unless -f $custom;
 215
 216         $$sym{is_custom} = $source;
 217         if (!$$sym{is_private}) {
 218             foreach my $subarch (@Architectures) {
 219                 (my $arch = $subarch) =~ s/arm(.*)/arm/;
 220                 $$sym{aliases}{$arch} = [] unless $$sym{aliases}{$arch};
 221                 push(@{$$sym{aliases}{$arch}}, $$sym{asm_sym});
 222             }
 223             $$sym{asm_sym} = "__".$$sym{asm_sym};
 224             $$sym{is_private} = 1;
 225         }
 226     }
 227 }
 228
 229 sub readAliases {
 230     my ($platformDir, $platformName) = @_;
 231     my $genericMap = File::Spec->join($platformDir, "syscall.map");
 232
 233     my %sym_to_c;
 234     foreach my $k (keys %Symbols) {
 235         $sym_to_c{$Symbols{$k}{asm_sym}} = $k;
 236     }
 237
 238     my @a = ();
 239     for my $arch (@Architectures) {
 240         (my $new_arch = $arch) =~ s/arm(.*)/arm/g;
 241         push(@a, $new_arch) unless grep { $_ eq $new_arch } @a;
 242     }
 243
 244     foreach my $arch (@a) {
 245         my $syscallFile = File::Spec->join($platformDir, $platformName, $arch, "syscall.map");
 246
 247         my @files = ();
 248         push(@files, IO::File->new($syscallFile, 'r'));
 249         die "$MyName: $syscallFile: $!\n" unless defined($files[$#files]);
 250         push(@files, IO::File->new($genericMap, 'r'));
 251         die "$MyName: $genericMap: $!\n" unless defined($files[$#files]);
 252
 253         foreach my $f (@files) {
 254             while (<$f>) {
 255                 next if /^#/;
 256                 chomp;
 257
 258                 my ($alias, $target_symbol) = split;
 259                 if (defined($target_symbol)) {
 260                     foreach my $sym (values %Symbols) {
 261                         # I've eliminated most of the ugly from this script except
 262                         # the need to try stripping underbars here.
 263                         if ($$sym{is_private}) {
 264                             next unless $$sym{asm_sym} eq $target_symbol;
 265                         } else {
 266                             (my $target = $target_symbol) =~ s/^__//;
 267                             next unless ($$sym{asm_sym} eq $target || $$sym{asm_sym} eq $target_symbol);
 268                         }
 269                         $$sym{aliases}{$arch} = [] unless $$sym{aliases}{$arch};
 270
 271                         die "$MyName: $arch $$sym{asm_sym} -> $alias: Duplicate alias.\n" if grep { $_ eq $alias } @{$$sym{aliases}{$arch}};
 272                         push(@{$$sym{aliases}{$arch}}, $alias);
 273
 274                         # last thing to do, if we aliased over a first class symbol, we need
 275                         # to mark it
 276                         my $c = $sym_to_c{$alias};
 277                         if ($Symbols{$c}) {
 278                             push(@{$Symbols{$c}{except}}, $arch);
 279                         }
 280                     }
 281                 }
 282             }
 283         }
 284     }
 285 }
 286
 287 ##########################################################################
 288 # Make a __xxx.s file: if it exists in the $CustomDir, just copy it, otherwise
 289 # create one.  We define the macro __SYSCALL_32BIT_ARG_BYTES so that SYS.h could
 290 # use that to define __SYSCALL dependent on the arguments' total size.
 291 ##########################################################################
 292 sub writeStubForSymbol {
 293     my ($f, $symbol) = @_;
 294
 295     my @conditions;
 296     for my $subarch (@Architectures) {
 297         (my $arch = $subarch) =~ s/arm(.*)/arm/;
 298         push(@conditions, "defined(__${arch}__)") unless grep { $_ eq $arch } @{$$symbol{except}};
 299     }
 300
 301     print $f "#define __SYSCALL_32BIT_ARG_BYTES $$symbol{bytes}\n";
 302     print $f "#include \"SYS.h\"\n\n";
 303     if (scalar(@conditions)) {
 304         printf $f "#if " . join(" || ", @conditions) . "\n";
 305         printf $f "__SYSCALL(%s, %s, %d)\n", $$symbol{asm_sym}, $$symbol{syscall}, $$symbol{nargs};
 306         if (!$$symbol{is_private} && (scalar(@conditions) < scalar(@Architectures))) {
 307             printf $f "#else\n";
 308             printf $f "__SYSCALL(%s, %s, %d)\n", "__".$$symbol{asm_sym}, $$symbol{syscall}, $$symbol{nargs};
 309         }
 310         printf $f "#endif\n\n";
 311     } else {
 312         # actually this isnt an inconsistency. kernel can expose what it wants but if all our arches
 313         # override it we need to honour that.
 314     }
 315 }
 316
 317 sub writeAliasesForSymbol {
 318     my ($f, $symbol) = @_;
 319
 320     foreach my $subarch (@Architectures) {
 321         (my $arch = $subarch) =~ s/arm(.*)/arm/;
 322
 323         next unless scalar($$symbol{aliases}{$arch});
 324
 325                                 printf $f "#if defined(__${arch}__)\n";
 326         foreach my $alias_sym (@{$$symbol{aliases}{$arch}}) {
 327             my $sym = (grep { $_ eq $arch } @{$$symbol{except}}) ? "__".$$symbol{asm_sym} : $$symbol{asm_sym};
 328
 329                                                 printf $f "\t.globl\t$alias_sym\n";
 330                                                 printf $f "\t.set\t$alias_sym, $sym\n";
 331         }
 332                                 printf $f "#endif\n\n";
 333     }
 334 }
 335
 336 usage() unless scalar(@ARGV) == 5;
 337 $CustomDir = $ARGV[1];
 338 die "$MyName: $CustomDir: No such directory\n" unless -d $CustomDir;
 339 $PlatformsDir = $ARGV[2];
 340 die "$MyName: $PlatformsDir: No such directory\n" unless -d $PlatformsDir;
 341 $PlatformName = $ARGV[3];
 342 die "$MyName: $PlatformsDir/$PlatformName: No such directory\n" unless -d "$PlatformsDir/$PlatformName";
 343 $OutDir = $ARGV[4];
 344 die "$MyName: $OutDir: No such directory\n" unless -d $OutDir;
 345
 346 readMaster($ARGV[0]);
 347 checkForCustomStubs($CustomDir);
 348 readAliases($PlatformsDir, $PlatformName);
 349
 350 ##########################################################################
 351 # copy the files specified in @Copy from the $CustomDir to $OutDir
 352 ##########################################################################
 353 for(@Copy) {
 354     my $custom = File::Spec->join($CustomDir, $_);
 355     my $path = File::Spec->join($OutDir, $_);
 356     print "Copy $custom -> $path\n";
 357     File::Copy::copy($custom, $path) || die "$MyName: copy($custom, $path): $!\n";
 358 }
 359
 360 ##########################################################################
 361 # make all the *.s files
 362 ##########################################################################
 363 my @src;
 364 my($k, $sym);
 365 while (($k, $sym) = each %Symbols)
 366 {
 367         my $srcname = $$sym{asm_sym} . ".s";
 368         my $outpath = File::Spec->join($OutDir, $srcname);
 369
 370         if ($$sym{is_custom}) {
 371                 my $custom = File::Spec->join($CustomDir, $$sym{is_custom});
 372                 File::Copy::copy($custom, $outpath);
 373                 print "Copied $outpath\n";
 374
 375                 print "Writing aliases for $srcname\n";
 376                 my $f = IO::File->new($outpath, 'a');
 377                 die "$MyName: $outpath: $!\n" unless defined($f);
 378                 writeAliasesForSymbol($f, $sym);
 379                 undef $f;
 380         } else {
 381                 my $f = IO::File->new($outpath, 'w');
 382                 die "$MyName: $outpath: $!\n" unless defined($f);
 383
 384                 printf "Creating $outpath\n";
 385                 writeStubForSymbol($f, $sym);
 386                 writeAliasesForSymbol($f, $sym);
 387                 undef $f;
 388         }
 389         push(@src, $srcname);
 390 }
 391
 392 ##########################################################################
 393 # create the Makefile.inc file from the list for files in @src and @CustomSrc
 394 ##########################################################################
 395 my $path = File::Spec->join($OutDir, 'stubs.list');
 396 my $f = IO::File->new($path, 'w');
 397 my @sources = sort(@src, @CustomSrc);
 398 for my $s (@sources) {
 399         printf $f File::Spec->join($OutDir, $s) . "\n";
 400 }
 401 undef $f;
 402 undef $path;
 403