[RFC 5/5] scripts/carray: change to using single awk invocation to generate .c

[Anup Patel]

On Mon, Dec 2, 2024 at 4:39 PM Ben Dooks <ben.dooks at codethink.co.uk> wrote:
>
> The shell script makes multiple call-outs to awk to get information
> from the configuration file. It would be easier to just write the
> whole thing in one .awk script and have the makefile altered to call
> that instead.
>
> There should be no functional difference other than the script type
> and has been tested with PLATFORM=generic build. This should be both
> quicker and easier to understand.
>
> Signed-off-by: Ben Dooks <ben.dooks at codethink.co.uk>
> ---
> v2:
>   - updated with the new bits from Samuel Holland's changes
>   - minor tweaks to the awk script to fix the output spacings
> v3:
>   - fixups for not being rather reliant on gawk (not on all distros)
>   - send error messages to stderr, otherwise they end up in .c output
>   - add no-var list a warning
>   - add debug output on env variable
>   - make awk script part of .sh script (easier to deal with change)
>   - fix rebase issues
> ---
>  scripts/carray.sh | 132 ++++++++++++++++++++++++++++++++++------------
>  1 file changed, 99 insertions(+), 33 deletions(-)
>
> diff --git a/scripts/carray.sh b/scripts/carray.sh
> index a2b05d3..475dfec 100755
> --- a/scripts/carray.sh
> +++ b/scripts/carray.sh
> @@ -45,42 +45,108 @@ if [ ! -f "${CONFIG_FILE}" ]; then
>         usage
>  fi
>
> -TYPE_HEADER=$(awk '{ if ($1 == "HEADER:") { printf $2; exit 0; } }' "${CONFIG_FILE}")
> -if [ -z "${TYPE_HEADER}" ]; then
> -       echo "Must specify HEADER: in input config file"
> -       usage
> -fi
> +# use single awk script to run conversion, but leave in .sh file as awk is
> +# bad for getopt, and leaves the original script name alone.
>
> -TYPE_NAME=$(awk '{ if ($1 == "TYPE:") { printf $2; for (i=3; i<=NF; i++) printf " %s", $i; exit 0; } }' "${CONFIG_FILE}")
> -if [ -z "${TYPE_NAME}" ]; then
> -       echo "Must specify TYPE: in input config file"
> -       usage
> -fi
> +awk -v"SCRIPT_NAME=${CONFIG_FILE}" -v "SCRIPT_NAME=`basename $0`" -v"VARLIST=${VAR_LIST}" '

The first "SCRIPT_NAME=" should be "CONFIG_FILE=".

> +function array_length(a)
> +{
> +    result = 0
>
> -ARRAY_NAME=$(awk '{ if ($1 == "NAME:") { printf $2; exit 0; } }' "${CONFIG_FILE}")
> -if [ -z "${ARRAY_NAME}" ]; then
> -       echo "Must specify NAME: in input config file"
> -       usage
> -fi
> +    for (i in a)
> +       result++
>
> -MEMBER_NAME=$(awk '{ if ($1 == "MEMBER-NAME:") { printf $2; exit 0; } }' "${CONFIG_FILE}")
> -MEMBER_TYPE=$(awk '{ if ($1 == "MEMBER-TYPE:") { printf $2; for (i=3; i<=NF; i++) printf " %s", $i; exit 0; } }' "${CONFIG_FILE}")
> -if [ -n "${MEMBER_NAME}" ] && [ -z "${MEMBER_TYPE}" ]; then
> -       echo "Must specify MEMBER-TYPE: when using MEMBER-NAME:"
> -       usage
> -fi
> +    return result
> +}
>
> -printf "// Generated with $(basename $0) from $(basename ${CONFIG_FILE})\n"
> -printf "#include <%s>\n\n" "${TYPE_HEADER}"
> +function get_fields(start, end)
> +{
> +    result = $start;
>
> -for VAR in ${VAR_LIST}; do
> -       printf "extern %s %s;\n" "${TYPE_NAME}" "${VAR}"
> -done
> -printf "\n"
> +    for (nr = start+1; nr <= end; nr++) {
> +       result = result " " $nr
> +    }
> +    return result;
> +}
> +
> +BEGIN {
> +      split(VARLIST,VAR_LIST," ")
> +}
> +
> +# process items from the config file
> +
> +/^HEADER:/     { TYPE_HEADER = $2 }
> +/^TYPE:/       { TYPE_NAME = get_fields(2, NF); }
> +/^NAME:/       { ARRAY_NAME = $2}
> +/^MEMBER-NAME:/        { MEMBER_NAME = $2 }
> +/^MEMBER-TYPE:/ { MEMBER_TYPE = get_fields(2, NF); }
> +
> +# code to dump the generated .c file once config file is processed
> +
> +END {
> +    # enable for debug
> +    if (length(ENVIRON["CARRAY_DEBUG"]) > 0) {
> +       print "ARRAY_NAME  " ARRAY_NAME > "/dev/stderr"
> +       print "TYPE_HEADER " TYPE_HEADER > "/dev/stderr"
> +       print "TYPE_NAME   " TYPE_NAME > "/dev/stderr"
> +
> +       print "VAR_LIST length is " array_length(VAR_LIST) > "/dev/stderr"
> +       for (v in VAR_LIST) {
> +           print "VAR_LIST " v  " = " VAR_LIST[v] > "/dev/stderr"
> +       }
> +    }
> +
> +    if (array_length(VAR_LIST) == 0) {
> +       print "Warning; no VAR list on command line"  > "/dev/stderr"
> +    }
> +
> +    if (length(ARRAY_NAME) == 0) {
> +       print "Must specify NAME: in input config file"  > "/dev/stderr"
> +       exit 1
> +    }
> +
> +    if (length(TYPE_NAME) == 0) {
> +       print "Must specify TYPE: in input config file"  > "/dev/stderr"
> +       exit 1
> +    }
> +
> +    if (length(TYPE_HEADER) == 0) {
> +       print "Must specify HEADER: in input config file"  > "/dev/stderr"
> +       exit 1
> +    }
> +
> +    if (length(MEMBER_NAME) > 0 && length(MEMBER_TYPE) == 0) {
> +       print "Must specify MEMBER-TYPE: when using MEMBER-NAME:" > "/dev/stderr"
> +       exit 1
> +    }
> +
> +    printf "// Generated with %s from %s\n", SCRIPT_NAME, CONFIG_FILE
> +    printf "// DO NOT EDIT THIS FILE DIRECTLY\n"
> +    printf "\n"
> +    printf("#include <%s>\n\n", TYPE_HEADER)
> +
> +    for (v in VAR_LIST) {
> +       printf("extern %s %s;\n", TYPE_NAME, VAR_LIST[v])
> +    }
> +    print ""
> +
> +    if (length(MEMBER_TYPE) > 0) {
> +       TYPE_NAME = MEMBER_TYPE;
> +    }
> +
> +    if (length(MEMBER_NAME) > 0) {
> +       VAR_SUFFIX = "." MEMBER_NAME;
> +    } else {
> +       VAR_SUFFIX = ""
> +    }
> +
> +    printf("%s *const %s[] = {\n", TYPE_NAME, ARRAY_NAME)
> +    for (v in VAR_LIST) {
> +       printf("\t&%s%s,\n", VAR_LIST[v], VAR_SUFFIX)
> +    }
> +    printf("\tNULL\n");
> +
> +    printf("};\n");
> +}
> +' < ${CONFIG_FILE} || usage
>
> -printf "%s *const %s[] = {\n" "${MEMBER_TYPE:-${TYPE_NAME}}" "${ARRAY_NAME}"
> -for VAR in ${VAR_LIST}; do
> -       printf "\t&%s,\n" "${VAR}${MEMBER_NAME:+.}${MEMBER_NAME}"
> -done
> -       printf "\tNULL\n"
> -printf "};\n"
> --
> 2.37.2.352.g3c44437643
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

Otherwise, it looks good to me.

Reviewed-by: Anup Patel <anup at brainfault.org>

Regards,
Anup