build-aux/declared.sh

   1 #! /bin/sh
   2 #
   3 # Copyright (C) 2006-2020 Free Software Foundation, Inc.
   4 #
   5 # This program is free software: you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 3 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  17 #
  18
  19 # This script determines the declared global symbols in a C header file.
  20 # Assumptions:
  21 # - The header files are in C, with only C89 comments.
  22 # - No use of macros with parameters.
  23 # - All global declarations are marked with 'extern'.
  24 # - All declarations end in ';' on the same line.
  25 # - Not more than one symbol is declared in a declaration.
  26
  27 # This script requires GNU sed.
  28
  29 # func_usage
  30 # outputs to stdout the --help usage message.
  31 func_usage ()
  32 {
  33   echo "\
  34 Usage: declared.sh [OPTION]... < SOURCE.h
  35
  36 Extracts the declared global symbols of a C header file.
  37
  38 Options:
  39       --help           print this help and exit
  40       --version        print version information and exit
  41
  42 Report bugs to <bruno@clisp.org>."
  43 }
  44
  45 # func_version
  46 # outputs to stdout the --version message.
  47 func_version ()
  48 {
  49   echo "declared.sh (GNU gnulib)"
  50   echo "Copyright (C) 2020 Free Software Foundation, Inc.
  51 License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
  52 This is free software: you are free to change and redistribute it.
  53 There is NO WARRANTY, to the extent permitted by law."
  54   echo "Written by" "Bruno Haible"
  55 }
  56
  57 # func_fatal_error message
  58 # outputs to stderr a fatal error message, and terminates the program.
  59 func_fatal_error ()
  60 {
  61   echo "declared.sh: *** $1" 1>&2
  62   echo "declared.sh: *** Stop." 1>&2
  63   exit 1
  64 }
  65
  66 # Command-line option processing.
  67 while test $# -gt 0; do
  68   case "$1" in
  69     --help | --hel | --he | --h )
  70       func_usage
  71       exit 0 ;;
  72    --version | --versio | --versi | --vers | --ver | --ve | --v )
  73       func_version
  74       exit 0 ;;
  75     -- )      # Stop option processing
  76       shift; break ;;
  77     -* )
  78       func_fatal_error "unrecognized option: $option"
  79       ;;
  80     * )
  81       break ;;
  82   esac
  83 done
  84
  85 if test $# -gt 0; then
  86   func_fatal_error "too many arguments"
  87 fi
  88
  89 # A sed expression that removes ANSI C and ISO C99 comments.
  90 sed_remove_comments="
  91 /[/][/*]/{
  92   ta
  93   :a
  94   s,^\\(\\([^\"'/]\\|\"\\([^\\\"]\\|[\\].\\)*\"\\|'\\([^\\']\\|[\\].\\)*'\\|[/][^\"'/*]\\|[/]\"\\([^\\\"]\\|[\\].\\)*\"\\|[/]'\\([^\\']\\|[\\].\\)*'\\)*\\)//.*,\\1,
  95   te
  96   s,^\\(\\([^\"'/]\\|\"\\([^\\\"]\\|[\\].\\)*\"\\|'\\([^\\']\\|[\\].\\)*'\\|[/][^\"'/*]\\|[/]\"\\([^\\\"]\\|[\\].\\)*\"\\|[/]'\\([^\\']\\|[\\].\\)*'\\)*\\)/[*]\\([^*]\\|[*][^/*]\\)*[*][*]*/,\\1 ,
  97   ta
  98   /^\\([^\"'/]\\|\"\\([^\\\"]\\|[\\].\\)*\"\\|'\\([^\\']\\|[\\].\\)*'\\|[/][^\"'/*]\\|[/]\"\\([^\\\"]\\|[\\].\\)*\"\\|[/]'\\([^\\']\\|[\\].\\)*'\\)*[/][*]/{
  99     s,^\\(\\([^\"'/]\\|\"\\([^\\\"]\\|[\\].\\)*\"\\|'\\([^\\']\\|[\\].\\)*'\\|[/][^\"'/*]\\|[/]\"\\([^\\\"]\\|[\\].\\)*\"\\|[/]'\\([^\\']\\|[\\].\\)*'\\)*\\)/[*].*,\\1 ,
 100     tu
 101     :u
 102     n
 103     s,^\\([^*]\\|[*][^/*]\\)*[*][*]*/,,
 104     tv
 105     s,^.*\$,,
 106     bu
 107     :v
 108   }
 109   :e
 110 }"
 111
 112 # Check that 'sed' supports the kind of regular expressions used in
 113 # sed_remove_comments. The use of \| meaning alternation of basic regular
 114 # expressions is a GNU extension.
 115 sed_test='s,^\(\(a\|X\)*\)//.*,\1,'
 116 sed_result=`echo 'aaa//bcd' | sed -e "$sed_test"`
 117 test "$sed_result" = 'aaa' \
 118   || func_fatal_error "The 'sed' program is not GNU sed. Try installing GNU sed."
 119
 120 # A sed expression that joins 'extern' declarations that are broken over
 121 # several lines.
 122 sed_join_multiline_externs='
 123 /^extern [^;]*$/{
 124   :a
 125   N
 126   s/\n/ /g
 127   /^extern [^;]*$/{
 128     ba
 129   }
 130 }'
 131
 132 # A sed expression that extracts the identifier of each 'extern' declaration.
 133 sed_extract_extern_declared='s/^extern [^()]*[ *]\([A-Za-z_][A-Za-z0-9_]*\) *[;(].*$/\1/p'
 134
 135 sed -e "$sed_remove_comments" \
 136   | sed -e "$sed_join_multiline_externs" \
 137   | sed -n -e "$sed_extract_extern_declared"