git_version.sh

   1 #!/bin/sh
   2 #
   3 # Generate some basic versioning information which can be piped to a header.
   4 #
   5 # Copyright (c) 2006-2007 Luc Verhaegen <libv@skynet.be>
   6 # Copyright (C) 2007 Hans Ulrich Niedermann <hun@n-dimensional.de>
   7 #
   8 # Permission is hereby granted, free of charge, to any person obtaining a
   9 # copy of this software and associated documentation files (the "Software"),
  10 # to deal in the Software without restriction, including without limitation
  11 # the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12 # and/or sell copies of the Software, and to permit persons to whom the
  13 # Software is furnished to do so, subject to the following conditions:
  14 #
  15 # The above copyright notice and this permission notice shall be included in
  16 # all copies or substantial portions of the Software.
  17 #
  18 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21 # THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  22 # OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  23 # ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24 # OTHER DEALINGS IN THE SOFTWARE.
  25 #
  26 # This script is based on the one written for xf86-video-unichrome by
  27 # Luc Verhaegen, but was rewritten almost completely by Hans Ulrich
  28 # Niedermann. The script contains a few bug fixes from Egbert Eich,
  29 # Matthias Hopf, Joerg Sonnenberger, and possibly others.
  30 #
  31 # The author thanks the nice people on #git for the assistance.
  32 #
  33 # Simple testing of this script:
  34 #   /sbin/busybox sh git_version.sh --example > moo.c \
  35 #     && gcc -Wall -Wextra -Wno-unused -o moo moo.c \
  36 #     && ./moo
  37 #   (bash should also do)
  38 #
  39 # For how to hook this up to your automake- and/or imake-based build
  40 # system, best take a look at how the RadeonHD.am and/or RadeonHD.tmpl
  41 # work in the xf86-video-radeonhd build system. For non-recursive make,
  42 # you can probably make things a little bit simpler.
  43 #
  44 # KNOWN BUGS:
  45 #  * Uses hyphenated ("git-foo-bar") program names, which git upstream
  46 #    have declared deprecated.
  47 #
  48
  49 # Help messages
  50 USAGE="[<option>...]"
  51 LONG_USAGE="\
  52 Options:
  53   -h, --help             Print this help message.
  54
  55   -k, --keep-if-no-repo  Keep old output file if no git repo found.
  56   -o, --output FILENAME  Set output file name.
  57   -q, --quiet            Quiet output.
  58   -s, --srcdir DIRNAME   Set source tree dir name.
  59   -x, --example          Print complete example program."
  60
  61 # The caller may have set these for us
  62 SED="${SED-sed}"
  63
  64 # Initialize
  65 working_dir="$(pwd)"
  66
  67 # Who am I?
  68 self="$(basename "$0")"
  69
  70 # Defaults
  71 ifndef_symbol="GIT_VERSION_H"
  72 outfile="-"
  73 print_example=false
  74 keep_if_no_repo=no
  75 quiet=false
  76 srcdir="$(pwd)"
  77
  78 # Parse command line parameter, affecting defaults
  79 while [ "x$1" != "x" ]
  80 do
  81     case "$1" in
  82         -x|--example)
  83             print_example=:
  84             ;;
  85         -o|--output)
  86             if shift; then
  87                 outfile="$1"
  88                 if [ "x$outfile" = "x-" ]; then
  89                     : # keep default ifndef_symbol
  90                 else
  91                     newdir=$(mktemp -t -d git_version_XXXXXX)
  92                     outfilenew="$newdir/$1.new"
  93                     ifndef_symbol=`basename "$outfile" | $SED 's|\.|_|g; s|[^A-Za-z0-9_]||g' | tr a-z A-Z`
  94                 fi
  95             else
  96                 echo "$self: Fatal: \"$1\" option requires parameter." >&2
  97                 exit 1
  98             fi
  99             ;;
 100         -q|--quiet)
 101             quiet=:
 102             ;;
 103         -h|--help)
 104             echo "Usage: ${self} $USAGE"
 105             [ -n "$LONG_USAGE" ] && echo "$LONG_USAGE"
 106             exit
 107             ;;
 108         -k|--keep-if-no-repo)
 109             keep_if_no_repo=yes
 110             ;;
 111         -s|--srcdir)
 112             if shift; then
 113                 if test -d "$1"; then
 114                     srcdir="$1"
 115                 else
 116                     echo "$self: Fatal: \"$1\" not a directory." >&2
 117                     exit 1
 118                 fi
 119             else
 120                 echo "$self: Fatal: \"$1\" option requires directory parameter." >&2
 121                 exit 1
 122             fi
 123             ;;
 124         *)
 125             echo "$self: Fatal: Invalid command line paramenter: \"$1\"" >&2
 126             exit 1
 127             ;;
 128     esac
 129     shift
 130 done
 131
 132 # If not printing to stdout, redirect stdout to output file
 133 rename_new_output=false
 134 if [ "x$outfile" = "x-" ]
 135 then
 136     : # keep using stdout
 137 else
 138     exec 1> "${outfilenew}"
 139 fi
 140
 141 # Done with creating output files, so we can change to source dir
 142 abs_srcdir="$(cd "$srcdir" && pwd)"
 143 cd "$srcdir"
 144
 145 # Write program header
 146 cat<<EOF
 147 /*
 148  * Basic versioning gathered from the git repository.
 149  * Automatically generated by $0.
 150  */
 151
 152 #ifndef ${ifndef_symbol}
 153 #define ${ifndef_symbol} 1
 154
 155 /* whether this is a dist tarball or not */
 156 #undef GIT_IS_DIST
 157
 158 EOF
 159
 160 # Backwards compatibility hack for git 1.6.0 (and people running the
 161 # latest pre-release version of git.)
 162 #
 163 # For now, we'll do this to support git 1.6, with minimal changes to
 164 # the rest of this script, but no guarantees how long this will work.
 165 # The hyphenated git-foo-bar names really are deprecated, and may
 166 # disappear in the future as more of git gets rewritten as built-in C
 167 # programs.  Google summer of code students and other git developers
 168 # are hard at work doing this, in order to make git more
 169 # portable/usable for Windows users.  As a result, some of the
 170 # git-foo-bar programs, which will be moved to the exec-dir directory
 171 # in git 1.6, may disappear altogether in the future.  Hence the only
 172 # truly safe and future-compatible way of running commands such as
 173 # git-diff-files, git-rev-parse, etc., are "git diff-files" and
 174 # "git rev-parse".  Here endeth the git portability sermon, which
 175 # I suspect will have as much effect as abstinence-only sex ed
 176 # classes.  :-)   TYT, 2008-07-08
 177
 178 execdir=$(git --exec-path 2> /dev/null)
 179 if test -n "$execdir"; then
 180     PATH=$PATH:$execdir
 181 fi
 182
 183 # Detect git tools (should work with old and new git versions)
 184 git_found=yes
 185 for git_tool in git-symbolic-ref git-rev-parse git-diff-files git-diff-index git git-describe
 186 do
 187     if [ x`which $git_tool 2>/dev/null` = "x" ]; then
 188         git_found="'$git_tool' not found"
 189         break
 190     fi
 191 done
 192
 193 # Determine git specific defines
 194 unset git_errors ||:
 195 if [ "x$git_found" = "xyes" ]; then
 196     git_version=`git --version`
 197     if [ "x$git_version" = "x" ]; then
 198         git_errors="${git_errors+${git_errors}; }error running 'git --version'"
 199     fi
 200 fi
 201
 202 git_repo=no
 203 # "git-rev-parse --git-dir" since git-0.99.7
 204 git_repo_dir="$(git-rev-parse --git-dir 2> /dev/null || true)"
 205 abs_repo_dir="$(cd "$git_repo_dir" && pwd)"
 206 # Only accept the found git repo iff it is in our top srcdir, as determined
 207 # by comparing absolute pathnames creaged by running pwd in the respective dir.
 208 if [ "x$git_repo_dir" != "x" ] && [ "x${abs_repo_dir}" = "x${abs_srcdir}/.git" ]; then
 209     git_repo=yes
 210     if [ "x$git_found" = "xyes" ]; then
 211         # git-1.4 and probably earlier understand "git-rev-parse HEAD"
 212         git_shaid=`git-describe --abbrev=12 --long 2>/dev/null ||
 213                    git-describe --abbrev=12 2>/dev/null ||
 214                    git-rev-parse HEAD`
 215         if [ "x$git_shaid" = "x" ]; then
 216             git_errors="${git_errors+${git_errors}; }error running 'git-rev-parse HEAD'"
 217         fi
 218         # git-1.4 and probably earlier understand "git-symbolic-ref HEAD"
 219         git_branch=`git-symbolic-ref HEAD | $SED -n 's|^refs/heads/||p'`
 220         if [ "x$git_branch" = "x" ]; then
 221             # This happens, is OK, and "(no branch)" is what "git branch" prints.
 222             git_branch="(no branch)"
 223         fi
 224         git_dirty=yes
 225         # git-1.4 does not understand "git-diff-files --quiet"
 226         # git-1.4 does not understand "git-diff-index --cached --quiet HEAD"
 227         if [ "x$(git-diff-files)" = "x" ] && [ "x$(git-diff-index --cached HEAD)" = "x" ]; then
 228             git_dirty=no
 229         fi
 230     fi
 231 fi
 232
 233 # Write git specific defines
 234 if [ "x$git_errors" = "x" ]; then
 235     echo "/* No errors occured while running git */"
 236     echo "#undef GIT_ERRORS"
 237 else
 238     echo "/* Some errors occured while running git */"
 239     echo "#define GIT_ERRORS \"${git_errors}\""
 240 fi
 241 echo ""
 242
 243 if [ "x$git_found" = "xyes" ]; then
 244     echo "/* git utilities found */"
 245     echo "#undef GIT_NOT_FOUND"
 246     echo "#define GIT_VERSION \"${git_version}\""
 247 else
 248     echo "/* git utilities not found */"
 249     echo "#define GIT_NOT_FOUND \"${git_found}\""
 250     echo "#undef GIT_VERSION"
 251 fi
 252 echo ""
 253
 254 if [ "x$git_repo" = "xno" ]; then
 255     echo "/* No git repo found, probably building from dist tarball */"
 256     echo "#undef GIT_REPO"
 257 else
 258     echo "/* git repo found */"
 259     echo "#define GIT_REPO 1"
 260     echo ""
 261     if [ "x$git_found" = "xyes" ]; then
 262         echo "/* Git SHA ID of last commit */"
 263         echo "#define GIT_SHAID \"${git_shaid}\""
 264         echo ""
 265
 266         echo "/* Branch this tree is on */"
 267         echo "#define GIT_BRANCH \"$git_branch\""
 268         echo ""
 269
 270         # Any uncommitted changes we should know about?
 271         # Or technically: Are the working tree or index dirty?
 272         if [ "x$git_dirty" = "xno" ]; then
 273             echo "/* SHA-ID uniquely defines the state of this code */"
 274             echo "#undef GIT_DIRTY"
 275         else
 276             echo "/* Local changes might be breaking things */"
 277             echo "#define GIT_DIRTY 1"
 278         fi
 279     fi
 280 fi
 281
 282 # Define a few immediately useful message strings
 283 cat<<EOF
 284
 285 /* Define GIT_MESSAGE such that
 286  *    printf("%s: built from %s", argv[0], GIT_MESSAGE);
 287  * forms a proper sentence.
 288  */
 289
 290 #ifdef GIT_DIRTY
 291 # define GIT_DIRTY_MSG " + changes"
 292 #else /* !GIT_DIRTY */
 293 # define GIT_DIRTY_MSG ""
 294 #endif /* GIT_DIRTY */
 295
 296 #ifdef GIT_ERRORS
 297 # define GIT_ERROR_MSG " with error: " GIT_ERRORS
 298 #else /* !GIT_ERRORS */
 299 # define GIT_ERROR_MSG ""
 300 #endif /* GIT_ERRORS */
 301
 302 #ifdef GIT_IS_DIST
 303 # define GIT_DIST_MSG "dist of "
 304 #else /* !GIT_IS_DIST */
 305 # define GIT_DIST_MSG ""
 306 #endif /* GIT_IS_DIST */
 307
 308 #ifdef GIT_REPO
 309 # ifdef GIT_NOT_FOUND
 310 #  define GIT_MESSAGE GIT_DIST_MSG "git sources without git: " GIT_NOT_FOUND
 311 # else /* !GIT_NOT_FOUND */
 312 #  define GIT_MESSAGE \\
 313        GIT_DIST_MSG \\
 314        "commit " GIT_SHAID GIT_DIRTY_MSG \\
 315        GIT_ERROR_MSG
 316 # endif /* GIT_NOT_FOUND */
 317 #else /* !GIT_REPO */
 318 # define GIT_MESSAGE GIT_DIST_MSG "non-git sources" GIT_ERROR_MSG
 319 #endif /* GIT_REPO */
 320
 321 #endif /* ${ifndef_symbol} */
 322 EOF
 323
 324 # Example program
 325 if "$print_example"
 326 then
 327     cat<<EOF
 328
 329 /* example program demonstrating the use of git_version.sh output */
 330 #include <stdio.h>
 331 #include <string.h>
 332
 333 #ifdef HAVE_CONFIG_H
 334 # include "config.h"
 335 #endif
 336
 337 int main(int argc, char *argv[])
 338 {
 339     const char *const idx = strrchr(argv[0], '/');
 340     const char *const prog = (idx)?(idx+1):(argv[0]);
 341 #ifdef PACKAGE_VERSION
 342     printf("%s: version %s, built from %s\n", prog, PACKAGE_VERSION, GIT_MESSAGE);
 343 #elif defined(GIT_MESSAGE)
 344     printf("%s: built from %s\n", prog, GIT_MESSAGE);
 345 #endif
 346     return 0;
 347 }
 348 EOF
 349 fi
 350
 351 # Change back to working dir for the remaining output file manipulations.
 352 cd "$working_dir"
 353
 354 # If necessary, overwrite outdated output file with new one
 355 if [ "x$outfile" != "x-" ]
 356 then
 357     if [ -f "$outfile" ]; then
 358         if [ "x$keep_if_no_repo" = "xyes" ] && [ "x$git_repo" = "xno" ]; then
 359             "$quiet" || echo "$self: Not a git repo, keeping existing $outfile" >&2
 360             rm -f "$outfilenew"
 361         elif cmp "$outfile" "$outfilenew" > /dev/null; then
 362             "$quiet" || echo "$self: Output is unchanged, keeping $outfile" >&2
 363             rm -f "$outfilenew"
 364         else
 365             echo "$self: Output has changed, updating $outfile" >&2
 366             mv -f "$outfilenew" "$outfile"
 367         fi
 368     else
 369         echo "$self: Output is new file, creating $outfile" >&2
 370         mv -f "$outfilenew" "$outfile"
 371     fi
 372     rmdir "$newdir"
 373 fi
 374
 375 # THE END.