sysdeps/unix/make-syscalls.sh

   1 #! /bin/sh
   2
   3 # Usage: make-syscalls.sh ../sysdeps/unix/common
   4 # Expects $sysdirs in environment.
   5
   6 ##############################################################################
   7
   8 # Syscall Signature Key Letters for BP Thunks:
   9 #
  10 # a: unchecked address (e.g., 1st arg to mmap)
  11 # b: non-NULL buffer (e.g., 2nd arg to read; return value from mmap)
  12 # B: optionally-NULL buffer (e.g., 4th arg to getsockopt)
  13 # f: buffer of 2 ints (e.g., 4th arg to socketpair)
  14 # F: 3rd arg to fcntl
  15 # i: scalar (any signedness & size: int, long, long long, enum, whatever)
  16 # I: 3rd arg to ioctl
  17 # n: scalar buffer length (e.g., 3rd arg to read)
  18 # N: pointer to value/return scalar buffer length (e.g., 6th arg to recvfrom)
  19 # p: non-NULL pointer to typed object (e.g., any non-void* arg)
  20 # P: optionally-NULL pointer to typed object (e.g., 2nd argument to gettimeofday)
  21 # s: non-NULL string (e.g., 1st arg to open)
  22 # S: optionally-NULL string (e.g., 1st arg to acct)
  23 # v: vararg scalar (e.g., optional 3rd arg to open)
  24 # V: byte-per-page vector (3rd arg to mincore)
  25 # W: wait status, optionally-NULL pointer to int (e.g., 2nd arg of wait4)
  26
  27 ptr='[abBfFINpPsSWV]'   # all pointer keyletters
  28 int='[inv]'             # all scalar keyletters
  29 typ='[ifnNpP]'          # typed-arg keyletters: we capture type for use in thunk
  30
  31 ##############################################################################
  32
  33 thisdir=$1; shift
  34
  35 echo ''
  36 echo \#### DIRECTORY = $thisdir
  37 # Check each sysdep dir with higher priority than this one,
  38 # and remove from $calls all the functions found in other dirs.
  39 # Punt when we reach the directory defining these syscalls.
  40 sysdirs=`for dir in $sysdirs; do
  41          test $dir = $thisdir && break; echo $dir; done`
  42 echo \#### SYSDIRS = $sysdirs
  43
  44 # Get the list of system calls for this directory.
  45 calls=`sed 's/#.*$//
  46 /^[     ]*$/d' $thisdir/syscalls.list`
  47
  48 calls=`echo "$calls" |
  49 while read file caller rest; do
  50   # Remove each syscall that is implemented by a file in $dir.
  51   # If a syscall specified a "caller", then only compile that syscall
  52   # if the caller function is also implemented in this directory.
  53   srcfile=-;
  54   for dir in $sysdirs; do
  55      { test -f $dir/$file.c && srcfile=$dir/$file.c; } ||
  56      { test -f $dir/$file.S && srcfile=$dir/$file.S; } ||
  57      { test -f $dir/$file.s && srcfile=$dir/$file.s; } ||
  58      { test x$caller != x- &&
  59         { { test -f $dir/$caller.c && srcfile=$dir/$caller.c; } ||
  60           { test -f $dir/$caller.S && srcfile=$dir/$caller.S; } ||
  61           { test -f $dir/$caller.s && srcfile=$dir/$caller.s; }; }; } && break;
  62   done;
  63   echo $file $srcfile $caller $rest;
  64 done`
  65
  66 # Any calls left?
  67 test -n "$calls" || exit 0
  68
  69 # Emit rules to compile the syscalls remaining in $calls.
  70 echo "$calls" |
  71 while read file srcfile caller syscall args strong weak; do
  72
  73   case x"$syscall" in
  74   x-) callnum=_ ;;
  75   *)
  76   # Figure out if $syscall is defined with a number in syscall.h.
  77   callnum=-
  78   eval `{ echo "#include <sysdep.h>";
  79         echo "callnum=SYS_ify ($syscall)"; } |
  80           $asm_CPP -D__OPTIMIZE__ - |
  81           sed -n -e "/^callnum=.*$syscall/d" \
  82                  -e "/^\(callnum=\)[    ]*\(.*\)/s//\1'\2'/p"`
  83   ;;
  84   esac
  85
  86   cancellable=
  87   noerrno=
  88   case $args in
  89   C*) cancellable=-cancel; args=`echo $args | sed 's/C:\?//'`;;
  90   E*) noerrno=_NOERRNO; args=`echo $args | sed 's/E:\?//'`;;
  91   V*) noerrno=_ERRVAL; args=`echo $args | sed 's/V:\?//'`;;
  92   esac
  93
  94   # Derive the number of arguments from the argument signature
  95   case $args in
  96   [0-9]) nargs=$args;;
  97   ?:) nargs=0;;
  98   ?:?) nargs=1;;
  99   ?:??) nargs=2;;
 100   ?:???) nargs=3;;
 101   ?:????) nargs=4;;
 102   ?:?????) nargs=5;;
 103   ?:??????) nargs=6;;
 104   ?:???????) nargs=7;;
 105   ?:????????) nargs=8;;
 106   ?:?????????) nargs=9;;
 107   esac
 108
 109   # Make sure only the first syscall rule is used, if multiple dirs
 110   # define the same syscall.
 111   echo ''
 112   echo "#### CALL=$file NUMBER=$callnum ARGS=$args SOURCE=$srcfile"
 113
 114  case x$srcfile"$callnum" in
 115  x--)
 116   # Undefined callnum for an extra syscall.
 117   if [ x$caller != x- ]; then
 118     if [ x$noerrno != x ]; then
 119       echo >&2 "$0: no number for $fileno, no-error syscall ($strong $weak)"
 120       exit 2
 121     fi
 122     echo "unix-stub-syscalls += $strong $weak"
 123   fi
 124   ;;
 125  x*-) ;; ### Do nothing for undefined callnum
 126  x-*)
 127   echo "ifeq (,\$(filter $file,\$(unix-syscalls)))"
 128
 129   case $weak in
 130   *@*)
 131     # The versioned symbols are only in the shared library.
 132     echo "ifneq (,\$(filter .os,\$(object-suffixes)))"
 133     ;;
 134   esac
 135   # Accumulate the list of syscall files for this directory.
 136   echo "unix-syscalls += $file"
 137   test x$caller = x- || echo "unix-extra-syscalls += $file"
 138
 139   # Emit a compilation rule for this syscall.
 140   case $weak in
 141   *@*)
 142     # The versioned symbols are only in the shared library.
 143     echo "\
 144 shared-only-routines += $file
 145 \$(objpfx)${file}.os: \\"
 146     ;;
 147   *)
 148     echo "\
 149 \$(foreach p,\$(sysd-rules-targets),\
 150 \$(foreach o,\$(object-suffixes),\$(objpfx)\$(patsubst %,\$p,$file)\$o)): \\"
 151     ;;
 152   esac
 153
 154   echo "                \$(common-objpfx)s-proto$cancellable.d"
 155   case x"$callnum" in
 156   x_)
 157   echo "\
 158         \$(make-target-directory)
 159         (echo '/* Dummy module requested by syscalls.list */'; \\"
 160   ;;
 161   x*)
 162   echo "\
 163         \$(make-target-directory)
 164         (echo '#include <sysdep$cancellable.h>'; \\
 165          echo 'PSEUDO$noerrno ($strong, $syscall, $nargs)'; \\
 166          echo ' ret$noerrno'; \\
 167          echo 'PSEUDO_END$noerrno($strong)'; \\
 168          echo 'libc_hidden_def ($strong)'; \\"
 169   ;;
 170   esac
 171
 172   # Append any weak aliases or versions defined for this syscall function.
 173
 174   # A shortcoming in the current gas is that it will only allow one
 175   # version-alias per symbol.  So we create new strong aliases as needed.
 176   vcount=""
 177
 178   for name in $weak; do
 179     case $name in
 180       *@@*)
 181         base=`echo $name | sed 's/@@.*//'`
 182         ver=`echo $name | sed 's/.*@@//'`
 183         if test -z "$vcount" ; then
 184           source=$strong
 185           vcount=1
 186         else
 187           source="${strong}_${vcount}"
 188           vcount=`expr $vcount + 1`
 189           echo "         echo 'strong_alias ($strong, $source)'; \\"
 190         fi
 191         echo "   echo 'default_symbol_version($source, $base, $ver)'; \\"
 192         ;;
 193       *@*)
 194         base=`echo $name | sed 's/@.*//'`
 195         ver=`echo $name | sed 's/.*@//'`
 196         if test -z "$vcount" ; then
 197           source=$strong
 198           vcount=1
 199         else
 200           source="${strong}_${vcount}"
 201           vcount=`expr $vcount + 1`
 202           echo "         echo 'strong_alias ($strong, $source)'; \\"
 203         fi
 204         echo "   echo 'symbol_version($source, $base, $ver)'; \\"
 205         ;;
 206       !*)
 207         name=`echo $name | sed 's/.//'`
 208         echo "   echo 'strong_alias ($strong, $name)'; \\"
 209         echo "   echo 'libc_hidden_def ($name)'; \\"
 210         ;;
 211       *)
 212         echo "   echo 'weak_alias ($strong, $name)'; \\"
 213         echo "   echo 'libc_hidden_weak ($name)'; \\"
 214         ;;
 215     esac
 216   done
 217
 218   # And finally, pipe this all into the compiler.
 219   echo '        ) | $(compile-syscall) '"\
 220 \$(foreach p,\$(patsubst %$file,%,\$(basename \$(@F))),\$(\$(p)CPPFLAGS))"
 221
 222   case $weak in
 223   *@*)
 224     # The versioned symbols are only in the shared library.
 225     echo endif
 226     ;;
 227   esac
 228
 229   echo endif
 230  ;;
 231  esac
 232
 233   case x"$callnum",$srcfile,$args in
 234   x[_-],-,* | x*,*.[sS],*V*) ;;
 235   x*,-,*$ptr* | x*,*.[sS],*$ptr*)
 236
 237     nv_weak=`for name in $weak; do
 238                 case $name in
 239                 *@*) ;;
 240                 *) echo $name;;
 241                 esac; done`
 242
 243     # choose the name with the fewest leading underscores, preferably none
 244     set `echo $strong $nv_weak |tr '@ \t' ' \n\n' |sort -r`
 245     callname=$1
 246
 247     # convert signature string to individual numbered arg names
 248     # e.g., i:ipbN -> i0 i1 p2 b3 N4
 249     set `echo $args |
 250         sed -e 's/^\(.\):\(.*\)/\2 <\10>/' \
 251             -e 's/^\([^ ]\)\(.*\)/\2 <\11>/' \
 252             -e 's/^\([^ ]\)\(.*\)/\2 <\12>/' \
 253             -e 's/^\([^ ]\)\(.*\)/\2 <\13>/' \
 254             -e 's/^\([^ ]\)\(.*\)/\2 <\14>/' \
 255             -e 's/^\([^ ]\)\(.*\)/\2 <\15>/' \
 256             -e 's/^\([^ ]\)\(.*\)/\2 <\16>/' \
 257             -e 's/^\([^ ]\)\(.*\)/\2 <\17>/' \
 258             -e 's/^\([^ ]\)\(.*\)/\2 <\18>/' \
 259             -e 's/^\([^ ]\)\(.*\)/\2 <\19>/'`
 260     rtn=$1; shift
 261     args=$*
 262     arglist=`echo $* |sed 's/ /, /g'`
 263
 264     # The best way to understand what's going on here is to examine
 265     # the output in BUILDDIR/sysd-syscalls.
 266
 267     # generate makefile envelope & rule head
 268     echo "ifeq (,\$(filter $file,\$(bp-thunks)))"
 269     echo "bp-thunks += $file"
 270     echo "\$(objpfx)\$(bppfx)$file.ob: \$(common-objpfx)s-proto-bp.d"
 271
 272     # generate macro head
 273     echo "      (echo '#define $callname(`echo $arglist | \
 274             sed -e 's/[<>]//g'`) `echo $rtn | \
 275             sed -e 's/<\('$typ'0\)>/\1v;/g' \
 276                 -e 's/<\(b0\)>/x0; extern char \1v;/g'` \\'; \\"
 277
 278     # generate extern decls of dummy variables for each arg
 279     echo "       echo '`echo $args | \
 280             sed -e 's/<\('$typ'[1-9]\)>/extern \1, \1v;/g' \
 281                 -e 's/<\([abBFIsSV][1-9]\)>/extern char \1v;/g' \
 282                 -e 's/<\([Wv][1-9]\)>/extern int \1v;/g'` \\'; \\"
 283
 284     # generate bounded-pointer thunk declarator
 285     echo "       echo '`echo $rtn | \
 286             sed -e 's/<\('$ptr'0\)>/__typeof (\1v) *__bounded/g' \
 287                 -e 's/<\('$int'0\)>/__typeof (\1v)/g'` BP_SYM ($strong) (`echo $arglist | \
 288             sed -e 's/<\('$ptr'[1-9]\)>/__typeof (\1v) *__bounded \1a/g' \
 289                 -e 's/<\('$int'[1-9]\)>/__typeof (\1v) \1a/g'`) { \\'; \\"
 290
 291     # generate extern primitive syscall declaration
 292     echo "       echo '  extern `echo $rtn | \
 293             sed -e 's/<\('$ptr'0\)>/__typeof (\1v) *__unbounded/g' \
 294                 -e 's/<\('$int'0\)>/__typeof (\1v)/g'` ($callname) (`echo $arglist | \
 295             sed -e 's/<\('$ptr'[1-9]\)>/__typeof (\1v) *__unbounded/g' \
 296                 -e 's/<\('$int'[1-9]\)>/__typeof (\1v)/g'`); \\'; \\"
 297
 298     # generate call the primtive system call, optionally wrapping bounds
 299     # around the result if the signature's return keyletter is `b'.
 300     echo "       echo '  return `echo $rtn |
 301             sed -e 's/<b0>/BOUNDED_N (/' \
 302                 -e 's/<.0>//'`($callname) (`echo $arglist | \
 303             sed -e 's/<\(a[1-9]\)>/__ptrvalue (\1a)/g' \
 304                 -e 's/<\(n[1-9]\)>, <\(V[1-9]\)>/\1a, CHECK_N_PAGES (\2a, \1a)/g' \
 305                 -e 's/<\(b[1-9]\)>, <\(n[1-9]\)>/CHECK_N (\1a, \2a), \2a/g' \
 306                 -e 's/<\(b[1-9]\)>, <\(N[1-9]\)>/CHECK_N (\1a, *CHECK_1 (\2a)), __ptrvalue (\2a)/g' \
 307                 -e 's/<\(B[1-9]\)>, <\(n[1-9]\)>/CHECK_N_NULL_OK (\1a, \2a), \2a/g' \
 308                 -e 's/<\(B[1-9]\)>, <\(N[1-9]\)>/CHECK_N_NULL_OK (\1a, *CHECK_1 (\2a)), __ptrvalue (\2a)/g' \
 309                 -e 's/<\(f[1-9]\)>/CHECK_N (\1a, 2)/g' \
 310                 -e 's/<\(i[1-9]\)>, <\(F[1-9]\)>/\1a, CHECK_FCNTL (\2a, \1a)/g' \
 311                 -e 's/<\(i[1-9]\)>, <\(I[1-9]\)>/\1a, CHECK_IOCTL (\2a, \1a)/g' \
 312                 -e 's/<\(p[1-9]\)>/CHECK_1 (\1a)/g' \
 313                 -e 's/<\([PW][1-9]\)>/CHECK_1_NULL_OK (\1a)/g' \
 314                 -e 's/<\(s[1-9]\)>/CHECK_STRING (\1a)/g' \
 315                 -e 's/<\(S[1-9]\)>/CHECK_STRING_NULL_OK (\1a)/g' \
 316                 -e 's/<\([ivn][1-9]\)>/\1a/g'`)`echo $rtn $args |
 317             sed -e 's/<b0>.*<\(n[1-9]\)>.*/, \1a)/' \
 318                 -e 's/<.0>.*//'`; \\'; \\"
 319
 320     echo "       echo '} \\'; \\"
 321
 322     echo "       echo 'libc_hidden_def (BP_SYM ($strong)) \\'; \\"
 323
 324     # generate thunk aliases
 325     for name in $nv_weak; do
 326       echo "     echo 'weak_alias (BP_SYM ($strong), BP_SYM ($name)) \\'; \\"
 327       echo "     echo 'libc_hidden_weak (BP_SYM ($name)) \\'; \\"
 328     done
 329
 330     # wrap up
 331     echo "\
 332          echo ''; \\
 333          echo '#include <bp-thunks.h>'; \\
 334         ) | \$(COMPILE.c) -x c -o \$@ -"
 335 ### Use this for debugging intermediate output:
 336 ###     ) >\$(@:.ob=.c)
 337 ###     \$(subst -c,-E,\$(COMPILE.c)) -o \$(@:.ob=.ib) \$(@:.ob=.c)
 338 ###     \$(COMPILE.c) -x cpp-output -o \$@ \$(@:.ob=.ib)"
 339     echo endif
 340     ;;
 341   esac
 342
 343 done