From 117fafdd16cf070cda130d6d8ac321947692055a Mon Sep 17 00:00:00 2001
From: Michael Vrable <mvrable@cs.ucsd.edu>
Date: Wed, 18 Jul 2007 12:03:46 -0700
Subject: [PATCH] Auto-generate a version number for the program with
 git-describe.

If compiled from a git repository, embed the version number (output from
git-describe) into the resulting binary.  If this does not work for
whatever reason, the version string embedded is "Unknown".
---
 .gitignore |  1 +
 Makefile   |  6 +++++-
 scandir.cc | 11 +++++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index 43a5c84..79734ec 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 lbs
 Makefile.dep
+version
diff --git a/Makefile b/Makefile
index 392c3da..e947b47 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 PACKAGES=sqlite3 uuid
 DEBUG=-g #-pg
 CXXFLAGS=-O -Wall -D_FILE_OFFSET_BITS=64 $(DEBUG) \
-	 `pkg-config --cflags $(PACKAGES)`
+	 `pkg-config --cflags $(PACKAGES)` -DLBS_VERSION=`cat version`
 LDFLAGS=$(DEBUG) -ltar `pkg-config --libs $(PACKAGES)`
 
 SRCS=format.cc localdb.cc ref.cc scandir.cc sha1.cc statcache.cc store.cc
@@ -10,6 +10,10 @@ OBJS=$(SRCS:.cc=.o)
 lbs : $(OBJS)
 	$(CXX) $(LDFLAGS) -o $@ $^
 
+version :
+	(git-describe || echo "Unknown") >version
+$(OBJS) : version
+
 dep:
 	touch Makefile.dep
 	makedepend -fMakefile.dep $(SRCS)
diff --git a/scandir.cc b/scandir.cc
index 980d843..5d7c9c5 100644
--- a/scandir.cc
+++ b/scandir.cc
@@ -33,6 +33,14 @@ using std::string;
 using std::vector;
 using std::ostream;
 
+/* Version information.  This will be filled in by the Makefile. */
+#ifndef LBS_VERSION
+#define LBS_VERSION Unknown
+#endif
+#define LBS_STRINGIFY(s) LBS_STRINGIFY2(s)
+#define LBS_STRINGIFY2(s) #s
+static const char lbs_version[] = LBS_STRINGIFY(LBS_VERSION);
+
 static TarSegmentStore *tss = NULL;
 
 /* Buffer for holding a single block of data read from a file. */
@@ -616,6 +624,8 @@ int main(int argc, char *argv[])
     {
         list<string>::const_iterator i;
 
+        printf("LBS Version: %s\n", lbs_version);
+
         printf("--dest=%s\n--localdb=%s\n\n",
                backup_dest.c_str(), localdb_dir.c_str());
 
@@ -686,6 +696,7 @@ int main(int argc, char *argv[])
     std::ofstream descriptor(desc_filename.c_str());
 
     descriptor << "Format: LBS Snapshot v0.1\n";
+    descriptor << "Producer: " << lbs_version << "\n";
     strftime(desc_buf, sizeof(desc_buf), "%Y-%m-%d %H:%M:%S %z", &time_buf);
     descriptor << "Date: " << desc_buf << "\n";
     descriptor << "Root: " << backup_root << "\n";
-- 
2.20.1