zsh/tools/require_tool.sh

   1 __require_tool_version_compare ()
   2 {
   3   (
   4     # Locally ignore failures, otherwise we'll exit whenever $1 and $2
   5     # are not equal!
   6     set +e
   7
   8 awk_strverscmp='
   9   # Use only awk features that work with 7th edition Unix awk (1978).
  10   # My, what an old awk you have, Mr. Solaris!
  11   END {
  12     while (length(v1) || length(v2)) {
  13       # Set d1 to be the next thing to compare from v1, and likewise for d2.
  14       # Normally this is a single character, but if v1 and v2 contain digits,
  15       # compare them as integers and fractions as strverscmp does.
  16       if (v1 ~ /^[0-9]/ && v2 ~ /^[0-9]/) {
  17         # Split v1 and v2 into their leading digit string components d1 and d2,
  18         # and advance v1 and v2 past the leading digit strings.
  19         for (len1 = 1; substr(v1, len1 + 1) ~ /^[0-9]/; len1++) continue
  20         for (len2 = 1; substr(v2, len2 + 1) ~ /^[0-9]/; len2++) continue
  21         d1 = substr(v1, 1, len1); v1 = substr(v1, len1 + 1)
  22         d2 = substr(v2, 1, len2); v2 = substr(v2, len2 + 1)
  23         if (d1 ~ /^0/) {
  24           if (d2 ~ /^0/) {
  25             # Compare two fractions.
  26             while (d1 ~ /^0/ && d2 ~ /^0/) {
  27               d1 = substr(d1, 2); len1--
  28               d2 = substr(d2, 2); len2--
  29             }
  30             if (len1 != len2 && ! (len1 && len2 && substr(d1, 1, 1) == substr(d2, 1, 1))) {
  31               # The two components differ in length, and the common prefix
  32               # contains only leading zeros.  Consider the longer to be less.
  33               d1 = -len1
  34               d2 = -len2
  35             } else {
  36               # Otherwise, compare as strings.
  37               d1 = "x" d1
  38               d2 = "x" d2
  39             }
  40           } else {
  41             # A fraction is less than an integer.
  42             exit 1
  43           }
  44         } else {
  45           if (d2 ~ /^0/) {
  46             # An integer is greater than a fraction.
  47             exit 2
  48           } else {
  49             # Compare two integers.
  50             d1 += 0
  51             d2 += 0
  52           }
  53         }
  54       } else {
  55         # The normal case, without worrying about digits.
  56         if (v1 == "") d1 = v1; else { d1 = substr(v1, 1, 1); v1 = substr(v1,2) }
  57         if (v2 == "") d2 = v2; else { d2 = substr(v2, 1, 1); v2 = substr(v2,2) }
  58       }
  59       if (d1 < d2) exit 1
  60       if (d1 > d2) exit 2
  61     }
  62   }
  63 '
  64     awk "$awk_strverscmp" v1="$1" v2="$2" /dev/null
  65     case $? in
  66       1)  echo '<';;
  67       0)  echo '=';;
  68       2)  echo '>';;
  69     esac
  70   )
  71 }
  72
  73
  74 __require_tool_fatal ()
  75 {
  76     echo $@ >/dev/stderr
  77     return 1
  78 }
  79
  80 # Usage: require_tool program version
  81 # Returns: 0 if $1 version if greater equals than $2, 1 otherwise.
  82 # In case of error, message is written on error output.
  83 #
  84 # Example: require_tool gcc 4.6
  85 # Use GCC environment variable if defined instead of lookup for the tool
  86 # in the environment.
  87 require_tool ()
  88 {
  89   envvar_name=$(echo $1 | tr '[:lower:]' '[:upper:]')
  90   tool=$(printenv $envvar_name || echo $1)
  91   local version=$($tool --version 2>/dev/null| \
  92     sed -n 's/.*[^0-9.]\([0-9]*\.[0-9.]*\).*/\1/p;q')
  93   if test x"$version" = x ; then
  94       echo "$tool is required" >/dev/stderr
  95       return 1
  96   fi
  97   case $(__require_tool_version_compare "$2" "$version") in
  98     '>')
  99           echo "$1 $2 or better is required: this is $tool $version" >/dev/stderr
 100           return 1
 101           ;;
 102   esac
 103 }
 104
 105 usage() {
 106     cat <<EOF
 107 NAME
 108     require_tool.sh - Ensure version of a tool is greater than the one expected
 109
 110 SYNOPSYS
 111     require_tool.sh [ -h ]
 112                     [ --help ]
 113                     [ TOOL MIN_VERSION ]
 114
 115 DESCRIPTION
 116     TOOL is the name or path of the program to check. If the name is specified, its
 117     path is deduced from PATH environment variable. If environment variable TOOL
 118     (in upper-case characters) is defined, considers its value as path to the tool.
 119
 120     MIN_VERSION is a string representing the minimum required version.
 121
 122 BEHAVIOR
 123     * locate path to the program.
 124     * execute $ TOOL_PATH --version
 125     * extract version from standard output.
 126     * compare this version to the expected one.
 127
 128 OPTIONS
 129     -h --help
 130         Display this message and exit 0
 131
 132 ERRORS
 133     if program is not found or its version is prior to expected version,
 134     a message is written to error output.
 135
 136 EXIT VALUE
 137     returns 0 if program version if greater equals than expected version,
 138     returns 1 otherwise.
 139
 140 EXAMPLE
 141     $ require_tool.sh emacs 23
 142     $ CC=g++ require_tool.sh cc 4.6
 143     $ require_tool.sh zsh 4.5
 144
 145 EOF
 146 }
 147
 148 for arg in $@; do
 149     case $arg in
 150         -h|--help)
 151             usage
 152             exit 0
 153             ;;
 154     esac
 155 done
 156 if [ $# -gt 2 ] ; then
 157     echo "ERROR: expecting 2 parameters. Please see option --help"
 158     exit 1
 159 fi
 160
 161 require_tool $@