scripts/gen-posix-conf-vars.awk

   1 # Generate posix-conf-vars-def.h with definitions for CONF_DEF{CONF} for each
   2 # configuration variable that getconf or sysconf may use.  Currently it is
   3 # equipped only to generate such macros for specification macros and for
   4 # SYSCONF macros in the _POSIX namespace.
   5
   6 BEGIN {
   7   prefix = ""
   8 }
   9
  10 $1 ~ /^#/ || $0 ~ /^\s*$/ {
  11   next
  12 }
  13
  14 # Begin a new prefix.
  15 $NF == "{" {
  16   type = $1
  17   prefix = $2
  18
  19   if (NF == 4)
  20     sc_prefix = $3
  21   else
  22     sc_prefix = "_SC"
  23
  24   next
  25 }
  26
  27 $1 == "}" {
  28   prefix = ""
  29   type = ""
  30   sc_prefix = ""
  31   next
  32 }
  33
  34 {
  35   if (prefix == "" && type == "" && sc_prefix == "") {
  36     printf ("Syntax error at %s:%d\n", FILENAME, FNR) > "/dev/stderr"
  37     exit 1
  38   }
  39
  40   # The prefix and variable names are indices and the value indicates what type
  41   # of variable it is.  The possible options are:
  42   # CONFSTR: A configuration string
  43   # SYSCONF: A numeric value
  44   # SPEC: A specification
  45   c = prefix "_" $1
  46   sc_prefixes[c] = sc_prefix
  47   prefix_conf[c] = type
  48   conf[c] = $1
  49 }
  50
  51 END {
  52   print "/* AUTOGENERATED by gen-posix-conf-vars.awk.  DO NOT EDIT.  */\n"
  53
  54   # Generate macros that specify if a sysconf macro is defined and/or set.
  55   for (c in prefix_conf) {
  56     printf "#ifndef _%s\n", c
  57     printf "# define CONF_DEF_%s CONF_DEF_UNDEFINED\n", c
  58     # CONFSTR have string values and they are not set or unset.
  59     if (prefix_conf[c] != "CONFSTR") {
  60       printf "#else\n"
  61       printf "# if _%s > 0\n", c
  62       printf "#  define CONF_DEF_%s CONF_DEF_DEFINED_SET\n", c
  63       printf "# else\n"
  64       printf "#  define CONF_DEF_%s CONF_DEF_DEFINED_UNSET\n", c
  65       printf "# endif\n"
  66     }
  67     printf "#endif\n\n"
  68
  69     # Build a name -> sysconf number associative array to print a C array at
  70     # the end.
  71     if (prefix_conf[c] == "SPEC")
  72       spec[c] = sc_prefixes[c] "_" conf[c]
  73   }
  74
  75   # Print the specification array.  Define the macro NEED_SPEC_ARRAY before
  76   # including posix-conf-vars.h to make it available in the compilation unit.
  77   print "#if NEED_SPEC_ARRAY"
  78   print "static const struct { const char *name; int num; } specs[] ="
  79   print "  {"
  80   for (s in spec) {
  81     printf "    { \"%s\", %s },\n", s, spec[s]
  82   }
  83   print "  };"
  84   print "static const size_t nspecs = sizeof (specs) / sizeof (specs[0]);"
  85   print "#endif"
  86 }