From 73641c4e73d8634eebe8fe00b96ba039da883b27 Mon Sep 17 00:00:00 2001
From: Dirk Hohndel <dirk@hohndel.org>
Date: Mon, 16 Jan 2017 15:56:56 -0800
Subject: [PATCH] build.sh: if new enough libgit2 is installed, use it

Right now this is only designed for Linux where current distros all should have
a new enough libgit2 (and our instructions tell people to install this with
system tools, so we should also use it).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
---
 CMakeLists.txt                  |  1 +
 cmake/Modules/FindLIBGIT2.cmake |  7 ++-
 scripts/build.sh                | 85 ++++++++++++++++++---------------
 3 files changed, 53 insertions(+), 40 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 09936c834..811480149 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,6 +22,7 @@ option(LIBMARBLE_FROM_PKGCONFIG "use pkg-config to retrieve marble" OFF)
 
 #Library Handling
 option(FORCE_LIBSSH "force linking with libssh to workaround libgit2 bug" ON)
+option(LIBGIT2_DYNAMIC "search for libgit2.so before libgit2.a" OFF)
 
 #Options regarding disabling parts of subsurface.
 option(NO_MARBLE "disable the marble widget" OFF)
diff --git a/cmake/Modules/FindLIBGIT2.cmake b/cmake/Modules/FindLIBGIT2.cmake
index cedb96d36..da51cc497 100644
--- a/cmake/Modules/FindLIBGIT2.cmake
+++ b/cmake/Modules/FindLIBGIT2.cmake
@@ -22,8 +22,13 @@ HINTS
     /usr/include
 )
 
+IF ( LIBGIT2_DYNAMIC )
+    SET( LIBGIT2_SO libgit2.so )
+ENDIF()
+
 FIND_LIBRARY( LIBGIT2_LIBRARIES
 NAMES
+    ${LIBGIT2_SO}
     libgit2.a
     git2
 HINTS
@@ -36,4 +41,4 @@ SET(LIBGIT2_LIBRARIES ${LIBGIT2_LIBRARIES} -lssl -lcrypto)
 
 INCLUDE( FindPackageHandleStandardArgs )
 FIND_PACKAGE_HANDLE_STANDARD_ARGS( git2 DEFAULT_MSG LIBGIT2_INCLUDE_DIR LIBGIT2_LIBRARIES )
-include_directories(${LIBGIT2_INCLUDE_DIR}})
\ No newline at end of file
+include_directories(${LIBGIT2_INCLUDE_DIR}})
diff --git a/scripts/build.sh b/scripts/build.sh
index e78b0e051..f60d7045b 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -3,7 +3,6 @@
 # this should be run from the src directory, the layout is supposed to
 # look like this:
 #.../src/subsurface
-#       /libgit2
 #       /marble-source
 #       /libdivecomputer
 #
@@ -73,37 +72,52 @@ export PKG_CONFIG_PATH=$INSTALL_ROOT/lib/pkgconfig:$PKG_CONFIG_PATH
 
 echo Building in $SRC, installing in $INSTALL_ROOT
 
-# build libgit2
-
-cd $SRC
-
-if [ ! -d libgit2 ] ; then
-	if [[ $1 = local ]] ; then
-		git clone $SRC/../libgit2 libgit2
-	else
-		git clone git://github.com/libgit2/libgit2
-	fi
-fi
-cd libgit2
-# let's build with a recent enough version of master for the latest features
-git fetch origin
-if ! git checkout v0.24.5 ; then
-	echo "Can't find the right tag in libgit2 - giving up"
-	exit 1
-fi
-mkdir -p build
-cd build
-cmake -DCMAKE_INSTALL_PREFIX=$INSTALL_ROOT -DCMAKE_BUILD_TYPE=Release -DBUILD_CLAR=OFF ..
-make -j4
-make install
-
+# set up the right file name extensions
 if [ $PLATFORM = Darwin ] ; then
-	# in order for macdeployqt to do its job correctly, we need the full path in the dylib ID
-	cd $INSTALL_ROOT/lib
-	NAME=$(otool -L libgit2.dylib | grep -v : | head -1 | cut -f1 -d\  | tr -d '\t')
-	echo $NAME | grep / > /dev/null 2>&1
-	if [ $? -eq 1 ] ; then
-		install_name_tool -id "$INSTALL_ROOT/lib/$NAME" "$INSTALL_ROOT/lib/$NAME"
+	SH_LIB_EXT=dylib
+else
+	SH_LIB_EXT=so
+
+	# check if we need to build libgit2 (and do so if necessary)
+
+	LIBGIT_ARGS=" -DLIBGIT2_DYNAMIC=ON "
+	LIBGIT=$(ldconfig -p | grep libgit2\\.so\\. | awk -F. '{ print $NF }')
+fi
+
+if [[ $PLATFORM = Darwin || "$LIBGIT" < "24" ]] ; then
+
+	LIBGIT_ARGS=" -DLIBGIT2_INCLUDE_DIR=$INSTALL_ROOT/include -DLIBGIT2_LIBRARIES=$INSTALL_ROOT/lib/libgit2.$SH_LIB_EXT "
+
+	cd $SRC
+
+	if [ ! -d libgit2 ] ; then
+		if [[ $1 = local ]] ; then
+			git clone $SRC/../libgit2 libgit2
+		else
+			git clone git://github.com/libgit2/libgit2
+		fi
+	fi
+	cd libgit2
+	# let's build with a recent enough version of master for the latest features
+	git fetch origin
+	if ! git checkout v0.24.5 ; then
+		echo "Can't find the right tag in libgit2 - giving up"
+		exit 1
+	fi
+	mkdir -p build
+	cd build
+	cmake -DCMAKE_INSTALL_PREFIX=$INSTALL_ROOT -DCMAKE_BUILD_TYPE=Release -DBUILD_CLAR=OFF ..
+	make -j4
+	make install
+
+	if [ $PLATFORM = Darwin ] ; then
+		# in order for macdeployqt to do its job correctly, we need the full path in the dylib ID
+		cd $INSTALL_ROOT/lib
+		NAME=$(otool -L libgit2.dylib | grep -v : | head -1 | cut -f1 -d\  | tr -d '\t')
+		echo $NAME | grep / > /dev/null 2>&1
+		if [ $? -eq 1 ] ; then
+			install_name_tool -id "$INSTALL_ROOT/lib/$NAME" "$INSTALL_ROOT/lib/$NAME"
+		fi
 	fi
 fi
 
@@ -227,12 +241,6 @@ fi
 
 # finally, build Subsurface
 
-if [ $PLATFORM = Darwin ] ; then
-	SH_LIB_EXT=dylib
-else
-	SH_LIB_EXT=so
-fi
-
 cd $SRC/subsurface
 for (( i=0 ; i < ${#BUILDS[@]} ; i++ )) ; do
 	SUBSURFACE_EXECUTABLE=${BUILDS[$i]}
@@ -250,8 +258,7 @@ for (( i=0 ; i < ${#BUILDS[@]} ; i++ )) ; do
 	export CMAKE_PREFIX_PATH="$INSTALL_ROOT/lib/cmake;${CMAKE_PREFIX_PATH}"
 	cmake -DCMAKE_BUILD_TYPE=Debug .. \
 		-DSUBSURFACE_TARGET_EXECUTABLE=$SUBSURFACE_EXECUTABLE \
-		-DLIBGIT2_INCLUDE_DIR=$INSTALL_ROOT/include \
-		-DLIBGIT2_LIBRARIES=$INSTALL_ROOT/lib/libgit2.$SH_LIB_EXT \
+		${LIBGIT_ARGS} \
 		-DLIBDIVECOMPUTER_INCLUDE_DIR=$INSTALL_ROOT/include \
 		-DLIBDIVECOMPUTER_LIBRARIES=$INSTALL_ROOT/lib/libdivecomputer.a \
 		-DMARBLE_INCLUDE_DIR=$INSTALL_ROOT/include \