tools/runlex.sh

   1 #! /bin/sh
   2
   3 #
   4 # runlex.sh
   5 # Script to run Lex/Flex.
   6 # First argument is the (quoted) name of the command; if it's null, that
   7 # means that neither Flex nor Lex was found, so we report an error and
   8 # quit.
   9 #
  10 # $Id$
  11 #
  12 # Wireshark - Network traffic analyzer
  13 # By Gerald Combs <gerald@wireshark.org>
  14 # Copyright 2007 Gerald Combs
  15 #
  16 # This program is free software; you can redistribute it and/or
  17 # modify it under the terms of the GNU General Public License
  18 # as published by the Free Software Foundation; either version 2
  19 # of the License, or (at your option) any later version.
  20 #
  21 # This program is distributed in the hope that it will be useful,
  22 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24 # GNU General Public License for more details.
  25 #
  26 # You should have received a copy of the GNU General Public License
  27 # along with this program; if not, write to the Free Software
  28 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  29 #
  30
  31 #
  32 # Get the name of the command to run, and then shift to get the arguments.
  33 #
  34 if [ $# -eq 0 ]
  35 then
  36         echo "Usage: runlex <lex/flex command to run> [ arguments ]" 1>&2
  37         exit 1
  38 fi
  39 LEX="$1"
  40 shift
  41 #
  42 # Check whether we have it.
  43 #
  44 if [ -z "${LEX}" ]
  45 then
  46         echo "Neither lex nor flex was found" 1>&2
  47         exit 1
  48 fi
  49
  50 SED="$1"
  51 shift
  52 #
  53 # Check whether we have it.
  54 #
  55 if [ -z "${SED}" ]
  56 then
  57         echo "Sed was not found" 1>&2
  58         exit 1
  59 fi
  60
  61 #
  62 # Process the flags.  We don't use getopt because we don't want to
  63 # embed complete knowledge of what options are supported by Lex/Flex.
  64 #
  65 flags=""
  66 outfile=lex.yy.c
  67 while [ $# -ne 0 ]
  68 do
  69         case "$1" in
  70
  71         -o*)
  72                 #
  73                 # Set the output file name.
  74                 #
  75                 outfile=`echo "$1" | ${SED} 's/-o\(.*\)/\1/'`
  76                 ;;
  77
  78         -*)
  79                 #
  80                 # Add this to the list of flags.
  81                 #
  82                 flags="$flags $1"
  83                 ;;
  84
  85         --|*)
  86                 #
  87                 # End of flags.
  88                 #
  89                 break
  90                 ;;
  91         esac
  92         shift
  93 done
  94
  95 #
  96 # OK, run it.
  97 #
  98 echo "Running ${LEX}"
  99 ${LEX} -o"$outfile" $flags "$@"
 100
 101 #
 102 # Did it succeed?
 103 #
 104 if [ $? -ne 0 ]
 105 then
 106         #
 107         # No.  Exit with the failing exit status.
 108         #
 109         exitstatus=$?
 110         echo "${LEX} failed: exit status $exitstatus"
 111         exit $exitstatus
 112 fi
 113
 114 #
 115 # Flex has the annoying habit of stripping all but the last component of
 116 # the "-o" flag argument and using that as the place to put the output.
 117 # This gets in the way of building in a directory different from the
 118 # source directory.  Try to work around this.
 119 #
 120 # Is the outfile where we think it is?
 121 #
 122 outfile_base=`basename "$outfile"`
 123 if [ "$outfile_base" != "$outfile" -a \( ! -r "$outfile" \) -a -r "$outfile_base" ]
 124 then
 125         #
 126         # No, it's not, but it is in the current directory.  Put it
 127         # where it's supposed to be.
 128         #
 129         mv "$outfile_base" "$outfile"
 130         if [ $? -ne 0 ]
 131         then
 132                 echo $?
 133         fi
 134 fi
 135
 136 echo "Wrote $outfile"
 137
 138 #
 139 # OK, now let's generate a header file declaring the relevant functions
 140 # defined by the .c file; if the .c file is .../foo.c, the header file
 141 # will be .../foo_lex.h.
 142 #
 143 # This works around some other Flex suckage, wherein it doesn't declare
 144 # the lex routine before defining it, causing compiler warnings.
 145 # XXX - newer versions of Flex support --header-file=, to generate the
 146 # appropriate header file.  With those versions, we should use that option.
 147 #
 148
 149 #
 150 # Get the name of the prefix; scan the source files for a %option prefix
 151 # line.  We use the last one.
 152 #
 153 echo "Getting prefix"
 154 prefix=`${SED} -n 's/%option[   ][      ]*prefix="\(.*\)".*/\1/p' "$@" | tail -1`
 155 if [ ! -z "$prefix" ]
 156 then
 157         prefixline="#define yylex ${prefix}lex"
 158 fi
 159
 160 #
 161 # Construct the name of the header file.
 162 #
 163 echo "Getting header file name"
 164 header_file=`dirname "$outfile"`/`basename "$outfile" .c`_lex.h
 165
 166 #
 167 # Spew out the declaration.
 168 #
 169 echo "Writing $header_file"
 170 cat <<EOF >$header_file
 171 /* This is generated by runlex.sh.  Do not edit it. */
 172 $prefixline
 173 #ifndef YY_DECL
 174 #define YY_DECL int yylex(void)
 175 #endif
 176 YY_DECL;
 177 EOF
 178
 179 echo "Wrote $header_file"