getcwd: Fix cross-compilation guess for musl libc.
[gnulib.git] / build-aux / git-version-gen
blob959f9889349a18ddf771bc57f9df9949297c6640
1 #!/bin/sh
2 # Print a version string.
3 scriptversion=2019-10-13.15; # UTC
5 # Copyright (C) 2007-2021 Free Software Foundation, Inc.
7 # This program is free software: you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; either version 3 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <https://www.gnu.org/licenses/>.
20 # This script is derived from GIT-VERSION-GEN from GIT: https://git-scm.com/.
21 # It may be run two ways:
22 # - from a git repository in which the "git describe" command below
23 # produces useful output (thus requiring at least one signed tag)
24 # - from a non-git-repo directory containing a .tarball-version file, which
25 # presumes this script is invoked like "./git-version-gen .tarball-version".
27 # In order to use intra-version strings in your project, you will need two
28 # separate generated version string files:
30 # .tarball-version - present only in a distribution tarball, and not in
31 # a checked-out repository. Created with contents that were learned at
32 # the last time autoconf was run, and used by git-version-gen. Must not
33 # be present in either $(srcdir) or $(builddir) for git-version-gen to
34 # give accurate answers during normal development with a checked out tree,
35 # but must be present in a tarball when there is no version control system.
36 # Therefore, it cannot be used in any dependencies. GNUmakefile has
37 # hooks to force a reconfigure at distribution time to get the value
38 # correct, without penalizing normal development with extra reconfigures.
40 # .version - present in a checked-out repository and in a distribution
41 # tarball. Usable in dependencies, particularly for files that don't
42 # want to depend on config.h but do want to track version changes.
43 # Delete this file prior to any autoconf run where you want to rebuild
44 # files to pick up a version string change; and leave it stale to
45 # minimize rebuild time after unrelated changes to configure sources.
47 # As with any generated file in a VC'd directory, you should add
48 # /.version to .gitignore, so that you don't accidentally commit it.
49 # .tarball-version is never generated in a VC'd directory, so needn't
50 # be listed there.
52 # Use the following line in your configure.ac, so that $(VERSION) will
53 # automatically be up-to-date each time configure is run (and note that
54 # since configure.ac no longer includes a version string, Makefile rules
55 # should not depend on configure.ac for version updates).
57 # AC_INIT([GNU project],
58 # m4_esyscmd([build-aux/git-version-gen .tarball-version]),
59 # [bug-project@example])
61 # Then use the following lines in your Makefile.am, so that .version
62 # will be present for dependencies, and so that .version and
63 # .tarball-version will exist in distribution tarballs.
65 # EXTRA_DIST = $(top_srcdir)/.version
66 # BUILT_SOURCES = $(top_srcdir)/.version
67 # $(top_srcdir)/.version:
68 # echo $(VERSION) > $@-t && mv $@-t $@
69 # dist-hook:
70 # echo $(VERSION) > $(distdir)/.tarball-version
73 me=$0
75 year=`expr "$scriptversion" : '\([^-]*\)'`
76 version="git-version-gen $scriptversion
78 Copyright $year Free Software Foundation, Inc.
79 There is NO warranty. You may redistribute this software
80 under the terms of the GNU General Public License.
81 For more information about these matters, see the files named COPYING."
83 usage="\
84 Usage: $me [OPTION]... \$srcdir/.tarball-version [TAG-NORMALIZATION-SED-SCRIPT]
85 Print a version string.
87 Options:
89 --prefix PREFIX prefix of git tags (default 'v')
90 --fallback VERSION
91 fallback version to use if \"git --version\" fails
93 --help display this help and exit
94 --version output version information and exit
96 Running without arguments will suffice in most cases."
98 prefix=v
99 fallback=
101 while test $# -gt 0; do
102 case $1 in
103 --help) echo "$usage"; exit 0;;
104 --version) echo "$version"; exit 0;;
105 --prefix) shift; prefix=${1?};;
106 --fallback) shift; fallback=${1?};;
108 echo "$0: Unknown option '$1'." >&2
109 echo "$0: Try '--help' for more information." >&2
110 exit 1;;
112 if test "x$tarball_version_file" = x; then
113 tarball_version_file="$1"
114 elif test "x$tag_sed_script" = x; then
115 tag_sed_script="$1"
116 else
117 echo "$0: extra non-option argument '$1'." >&2
118 exit 1
119 fi;;
120 esac
121 shift
122 done
124 if test "x$tarball_version_file" = x; then
125 echo "$usage"
126 exit 1
129 tag_sed_script="${tag_sed_script:-s/x/x/}"
131 nl='
134 # Avoid meddling by environment variable of the same name.
136 v_from_git=
138 # First see if there is a tarball-only version file.
139 # then try "git describe", then default.
140 if test -f $tarball_version_file
141 then
142 v=`cat $tarball_version_file` || v=
143 case $v in
144 *$nl*) v= ;; # reject multi-line output
145 esac
146 test "x$v" = x \
147 && echo "$0: WARNING: $tarball_version_file is damaged" 1>&2
150 if test "x$v" != x
151 then
152 : # use $v
153 # Otherwise, if there is at least one git commit involving the working
154 # directory, and "git describe" output looks sensible, use that to
155 # derive a version string.
156 elif test "`git log -1 --pretty=format:x . 2>&1`" = x \
157 && v=`git describe --abbrev=4 --match="$prefix*" HEAD 2>/dev/null \
158 || git describe --abbrev=4 HEAD 2>/dev/null` \
159 && v=`printf '%s\n' "$v" | sed "$tag_sed_script"` \
160 && case $v in
161 $prefix[0-9]*) ;;
162 *) (exit 1) ;;
163 esac
164 then
165 # Is this a new git that lists number of commits since the last
166 # tag or the previous older version that did not?
167 # Newer: v6.10-77-g0f8faeb
168 # Older: v6.10-g0f8faeb
169 vprefix=`expr "X$v" : 'X\(.*\)-g[^-]*$'` || vprefix=$v
170 case $vprefix in
171 *-*) : git describe is probably okay three part flavor ;;
173 : git describe is older two part flavor
174 # Recreate the number of commits and rewrite such that the
175 # result is the same as if we were using the newer version
176 # of git describe.
177 vtag=`echo "$v" | sed 's/-.*//'`
178 commit_list=`git rev-list "$vtag"..HEAD 2>/dev/null` \
179 || { commit_list=failed;
180 echo "$0: WARNING: git rev-list failed" 1>&2; }
181 numcommits=`echo "$commit_list" | wc -l`
182 v=`echo "$v" | sed "s/\(.*\)-\(.*\)/\1-$numcommits-\2/"`;
183 test "$commit_list" = failed && v=UNKNOWN
185 esac
187 # Change the penultimate "-" to ".", for version-comparing tools.
188 # Remove the "g" to save a byte.
189 v=`echo "$v" | sed 's/-\([^-]*\)-g\([^-]*\)$/.\1-\2/'`;
190 v_from_git=1
191 elif test "x$fallback" = x || git --version >/dev/null 2>&1; then
192 v=UNKNOWN
193 else
194 v=$fallback
197 v=`echo "$v" |sed "s/^$prefix//"`
199 # Test whether to append the "-dirty" suffix only if the version
200 # string we're using came from git. I.e., skip the test if it's "UNKNOWN"
201 # or if it came from .tarball-version.
202 if test "x$v_from_git" != x; then
203 # Don't declare a version "dirty" merely because a timestamp has changed.
204 git update-index --refresh > /dev/null 2>&1
206 dirty=`exec 2>/dev/null;git diff-index --name-only HEAD` || dirty=
207 case "$dirty" in
208 '') ;;
209 *) # Append the suffix only if there isn't one already.
210 case $v in
211 *-dirty) ;;
212 *) v="$v-dirty" ;;
213 esac ;;
214 esac
217 # Omit the trailing newline, so that m4_esyscmd can use the result directly.
218 printf %s "$v"
220 # Local variables:
221 # eval: (add-hook 'before-save-hook 'time-stamp)
222 # time-stamp-start: "scriptversion="
223 # time-stamp-format: "%:y-%02m-%02d.%02H"
224 # time-stamp-time-zone: "UTC0"
225 # time-stamp-end: "; # UTC"
226 # End: