[lttng-dev] [PATCH babeltrace] Add git version string

[Michael Jeanson]

Signed-off-by: Michael Jeanson <mjeanson at efficios.com>
---
 .gitignore                    |  2 +
 cli/babeltrace-cfg-cli-args.c |  7 +++-
 include/Makefile.am           | 74 ++++++++++++++++++++++++++++++++++-
 include/version.h             | 28 +++++++++++++
 4 files changed, 109 insertions(+), 2 deletions(-)
 create mode 100644 include/version.h

diff --git a/.gitignore b/.gitignore
index a1740cb1..edcf8edc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -64,6 +64,8 @@ plugins/ctf/common/metadata/parser.output
 /cli/babeltrace-log.bin
 /include/config.h
 /include/config.h.in
+/include/version.i
+/include/version.i.tmp
 /config.status
 *.log
 aclocal.m4
diff --git a/cli/babeltrace-cfg-cli-args.c b/cli/babeltrace-cfg-cli-args.c
index 8f01e64b..7783f25a 100644
--- a/cli/babeltrace-cfg-cli-args.c
+++ b/cli/babeltrace-cfg-cli-args.c
@@ -41,6 +41,7 @@
 #include "babeltrace-cfg.h"
 #include "babeltrace-cfg-cli-args.h"
 #include "babeltrace-cfg-cli-args-connect.h"
+#include "version.h"
 
 /*
  * Error printf() macro which prepends "Error: " the first time it's
@@ -729,7 +730,11 @@ end:
 static
 void print_version(void)
 {
-	puts("Babeltrace " VERSION);
+	if (GIT_VERSION[0] == '\0') {
+		puts("Babeltrace " VERSION);
+	} else {
+		puts("Babeltrace " VERSION  " - " GIT_VERSION);
+	}
 }
 
 /*
diff --git a/include/Makefile.am b/include/Makefile.am
index c026e74c..669e003b 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -1,3 +1,73 @@
+##
+## This target generates an include file that contains the git version
+## string of the current branch, it must be continuously updated when
+## we build in the git repo and shipped in dist tarballs to reflect the
+## status of the tree when it was generated. If the tree is clean and
+## the current commit is tag a starting with "v", consider this a
+## release version and set an empty git version.
+##
+## Here is what the inline script does:
+##
+## First, delete any stale "version.i.tmp" file.
+##
+## If "bootstrap" and ".git" exists in the top source directory and the git
+## executable is available, get the current git version string in the form:
+##
+##  "latest_tag"(-"number_of_commits_on_top")(-g"latest_commit_hash")(-dirty)
+##
+## And store it in "version.i.tmp", if the current commit is tagged, the tag
+## starts with "v" and the tree is clean, consider this a release version and
+## overwrite the git version with an empty string in "version.i.tmp".
+##
+## If we don't have a "version.i.tmp" nor a "version.i", generate an empty
+## string as a failover.
+##
+## If we don't have a "version.i" or we have both files and they are different,
+## copy "version.i.tmp" over "version.i". This way the dependent targets are
+## only rebuilt when the version string changes.
+##
+
+version_verbose = $(version_verbose_ at AM_V@)
+version_verbose_ = $(version_verbose_ at AM_DEFAULT_V@)
+version_verbose_0 = @echo "  GEN       " $@;
+
+version.i:
+	$(version_verbose)rm -f version.i.tmp; \
+	if (test -r "$(top_srcdir)/bootstrap" && test -r "$(top_srcdir)/.git") && \
+			test -x "`which git 2>&1;true`"; then \
+		GIT_VERSION_STR="`cd "$(top_srcdir)" && git describe --tags --dirty`"; \
+		GIT_CURRENT_TAG="`cd "$(top_srcdir)" && git describe --tags --exact-match --match="v[0-9]*" HEAD 2> /dev/null`"; \
+		echo "#define GIT_VERSION \"$$GIT_VERSION_STR\"" > version.i.tmp; \
+		if ! $(GREP) -- "-dirty" version.i.tmp > /dev/null && \
+				test "x$$GIT_CURRENT_TAG" != "x"; then \
+			echo "#define GIT_VERSION \"\"" > version.i.tmp; \
+		fi; \
+	fi; \
+	if test ! -f version.i.tmp; then \
+		if test ! -f version.i; then \
+			echo '#define GIT_VERSION ""' > version.i; \
+		fi; \
+	elif test ! -f version.i || \
+			test x"`cat version.i.tmp`" != x"`cat version.i`"; then \
+		mv version.i.tmp version.i; \
+	fi; \
+	rm -f version.i.tmp; \
+	true
+
+##
+## version.i is defined as a .PHONY target even if it's a real file,
+## we want the target to be re-run on every make.
+##
+.PHONY: version.i
+
+CLEANFILES = version.i.tmp
+
+##
+## Only clean "version.i" on dist-clean, we need to keep it on regular
+## clean when it's part of a dist tarball.
+##
+DISTCLEANFILES = version.i
+
 # Core API
 babeltraceincludedir = "$(includedir)/babeltrace"
 babeltraceinclude_HEADERS = \
@@ -151,4 +221,6 @@ noinst_HEADERS = \
 	babeltrace/plugin/plugin-so-internal.h \
 	babeltrace/prio-heap-internal.h \
 	babeltrace/ref-internal.h \
-	babeltrace/values-internal.h
+	babeltrace/values-internal.h \
+	version.h \
+	version.i
diff --git a/include/version.h b/include/version.h
new file mode 100644
index 00000000..4f802517
--- /dev/null
+++ b/include/version.h
@@ -0,0 +1,28 @@
+#ifndef VERSION_H
+#define VERSION_H
+
+/*
+ * Copyright (C) 2018 Michael Jeanson <mjeanson at efficios.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "version.i"
+
+#endif /* VERSION_H */
-- 
2.17.0