glibc/scripts/gen-posix-conf-vars.awk

# 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
  next
}

$1 == "}" {
  prefix = ""
  type = ""
  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
  conf[prefix][$1] = type
}

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 (p in conf) {
    for (c in conf[p]) {
      printf "#ifndef _%s_%s\n", p, c
      printf "# define CONF_DEF_%s_%s CONF_DEF_UNDEFINED\n", p, c
      # CONFSTR have string values and they are not set or unset.
      if (conf[p][c] != "CONFSTR") {
	printf "#else\n"
	printf "# if _%s_%s > 0\n", p, c
	printf "#  define CONF_DEF_%s_%s CONF_DEF_DEFINED_SET\n", p, c
	printf "# else\n"
	printf "#  define CONF_DEF_%s_%s CONF_DEF_DEFINED_UNSET\n", p, c
	printf "# endif\n"
      }
      printf "#endif\n\n"
    }
  }
}