#! /bin/sh # # runlex.sh # Script to run Lex/Flex. # First argument is the (quoted) name of the command; if it's null, that # means that neither Flex nor Lex was found, so we report an error and # quit. # # @(#) $Header: /tcpdump/master/libpcap/runlex.sh,v 1.1.2.4 2007/12/31 03:39:06 guy Exp $ # # # Get the name of the command to run, and then shift to get the arguments. # if [ $# -eq 0 ] then echo "Usage: runlex [ arguments ]" 1>&2 exit 1 fi LEX="$1" shift # # Check whether we have Lex or Flex. # if [ -z "${LEX}" ] then echo "Neither lex nor flex was found" 1>&2 exit 1 fi # # Process the flags. We don't use getopt because we don't want to # embed complete knowledge of what options are supported by Lex/Flex. # flags="" outfile=lex.yy.c while [ $# -ne 0 ] do case "$1" in -o*) # # Set the output file name. # outfile=`echo "$1" | sed 's/-o\(.*\)/\1/'` ;; -*) # # Add this to the list of flags. # flags="$flags $1" ;; --|*) # # End of flags. # break ;; esac shift done # # Is it Lex, or is it Flex? # if [ "${LEX}" = flex ] then # # It's Flex. # have_flex=yes # # Does it support the --noFUNCTION options? If so, we pass # --nounput, as at least some versions that support those # options don't support disabling yyunput by defining # YY_NO_UNPUT. # if flex --help | egrep noFUNCTION >/dev/null then flags="$flags --nounput" # # Does it support -R, for generating reentrant scanners? # If so, we're not currently using that feature, but # it'll generate some unused functions anyway - and there # won't be any header file declaring them, so there'll be # defined-but-not-declared warnings. Therefore, we use # --noFUNCTION options to suppress generating those # functions. # if flex --help | egrep reentrant >/dev/null then flags="$flags --noyyget_lineno --noyyget_in --noyyget_out --noyyget_leng --noyyget_text --noyyset_lineno --noyyset_in --noyyset_out" fi fi else # # It's Lex. # have_flex=no fi # # OK, run it. # If it's lex, it doesn't support -o, so we just write to # lex.yy.c and, if it succeeds, rename it to the right name, # otherwise we remove lex.yy.c. # If it's flex, it supports -o, so we use that - flex with -P doesn't # write to lex.yy.c, it writes to a lex.{prefix from -P}.c. # if [ $have_flex = yes ] then ${LEX} $flags -o"$outfile" "$@" # # Did it succeed? # status=$? if [ $status -ne 0 ] then # # No. Exit with the failing exit status. # exit $status fi # # Flex has the annoying habit of stripping all but the last # component of the "-o" flag argument and using that as the # place to put the output. This gets in the way of building # in a directory different from the source directory. Try # to work around this. # # Is the outfile where we think it is? # outfile_base=`basename "$outfile"` if [ "$outfile_base" != "$outfile" -a \( ! -r "$outfile" \) -a -r "$outfile_base" ] then # # No, it's not, but it is in the current directory. Put it # where it's supposed to be. # mv "$outfile_base" "$outfile" # # Did that succeed? # status=$? if [ $status -ne 0 ] then # # No. Exit with the failing exit status. # exit $status fi fi else ${LEX} $flags "$@" # # Did it succeed? # status=$? if [ $status -ne 0 ] then # # No. Get rid of any lex.yy.c file we generated, and # exit with the failing exit status. # rm -f lex.yy.c exit $status fi # # OK, rename lex.yy.c to the right output file. # mv lex.yy.c "$outfile" # # Did that succeed? # status=$? if [ $status -ne 0 ] then # # No. Get rid of any lex.yy.c file we generated, and # exit with the failing exit status. # rm -f lex.yy.c exit $status fi fi # # OK, now let's generate a header file declaring the relevant functions # defined by the .c file; if the .c file is .../foo.c, the header file # will be .../foo.h. # # This works around some other Flex suckage, wherein it doesn't declare # the lex routine before defining it, causing compiler warnings. # XXX - newer versions of Flex support --header-file=, to generate the # appropriate header file. With those versions, we should use that option. # # # Get the name of the prefix; scan the source files for a %option prefix # line. We use the last one. # prefix=`sed -n 's/%option[ ][ ]*prefix="\(.*\)".*/\1/p' "$@" | tail -1` if [ ! -z "$prefix" ] then prefixline="#define yylex ${prefix}lex" fi # # Construct the name of the header file. # header_file=`dirname "$outfile"`/`basename "$outfile" .c`.h # # Spew out the declaration. # cat <$header_file /* This is generated by runlex.sh. Do not edit it. */ $prefixline #ifndef YY_DECL #define YY_DECL int yylex(void) #endif YY_DECL; EOF