# Generate posix-conf-vars-def.h with definitions for CONF_DEF{CONF} for each

# configuration variable that getconf or sysconf may use.  Currently it is

# equipped only to generate such macros for specification macros and for

# SYSCONF macros in the _POSIX namespace.

BEGIN {

  prefix = ""

}

$1 ~ /^#/ || $0 ~ /^\s*$/ {

  next

}

# Begin a new prefix.

$NF == "{" {

  type = $1

  prefix = $2

  if (NF == 4)

    sc_prefix = $3

  else

    sc_prefix = "_SC"

  next

}

$1 == "}" {

  prefix = ""

  type = ""

  sc_prefix = ""

  next

}

{

  if (prefix == "" && type == "" && sc_prefix == "") {

    printf ("Syntax error at %s:%d\n", FILENAME, FNR) > "/dev/stderr"

    exit 1

  }

  # The prefix and variable names are indices and the value indicates what type

  # of variable it is.  The possible options are:

  # CONFSTR: A configuration string

  # SYSCONF: A numeric value

  # SPEC: A specification

  c = prefix "_" $1

  sc_prefixes[c] = sc_prefix

  prefix_conf[c] = type

  conf[c] = $1

}

END {

  print "/* AUTOGENERATED by gen-posix-conf-vars.awk.  DO NOT EDIT.  */\n"

  # Generate macros that specify if a sysconf macro is defined and/or set.

  for (c in prefix_conf) {

    printf "#ifndef _%s\n", c

    printf "# define CONF_DEF_%s CONF_DEF_UNDEFINED\n", c

    # CONFSTR have string values and they are not set or unset.

    if (prefix_conf[c] != "CONFSTR") {

      printf "#else\n"

      printf "# if _%s > 0\n", c

      printf "#  define CONF_DEF_%s CONF_DEF_DEFINED_SET\n", c

      printf "# else\n"

      printf "#  define CONF_DEF_%s CONF_DEF_DEFINED_UNSET\n", c

      printf "# endif\n"

    }

    printf "#endif\n\n"

    # Build a name -> sysconf number associative array to print a C array at

    # the end.

    if (prefix_conf[c] == "SPEC")

      spec[c] = sc_prefixes[c] "_" conf[c]

  }

  # Print the specification array.  Define the macro NEED_SPEC_ARRAY before

  # including posix-conf-vars.h to make it available in the compilation unit.

  print "#if NEED_SPEC_ARRAY"

  print "static const struct { const char *name; int num; } specs[] ="

  print "  {"

  for (s in spec) {

    printf "    { \"%s\", %s },\n", s, spec[s]

  }

  print "  };"

  print "static const size_t nspecs = sizeof (specs) / sizeof (specs[0]);"

  print "#endif"

}