[PATCH v2] libtracefs: Update libtracefs.pc when version changes

[PATCH v2] libtracefs: Update libtracefs.pc when version changes

[Steven Rostedt]

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

When the libtracefs version changes, the libtracefs.pc needs to be updated,
otherwise it may install the wrong version number.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
Changes since v1:
  - Fixed version define calculation
  - Fixed alignment of updating tfs_version.h
  - Remove tfs_version.h in make clean

 .gitignore |  1 +
 Makefile   | 31 ++++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index d2d39fb..ff3e014 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,3 +8,4 @@ lib/
 patches/
 build_prefix
 build_uninstall
+tfs_version.h
diff --git a/Makefile b/Makefile
index 9de3217..a3ae0b8 100644
--- a/Makefile
+++ b/Makefile
@@ -203,10 +203,12 @@ endef
 
 BUILD_PREFIX := $(BUILD_OUTPUT)/build_prefix
 
+VERSION_FILE = tfs_version.h
+
 $(BUILD_PREFIX): force
 	$(Q)$(call build_prefix,$(prefix))
 
-$(PKG_CONFIG_FILE) : ${PKG_CONFIG_SOURCE_FILE}.template $(BUILD_PREFIX)
+$(PKG_CONFIG_FILE) : ${PKG_CONFIG_SOURCE_FILE}.template $(BUILD_PREFIX) $(VERSION_FILE)
 	$(Q) $(call do_make_pkgconfig_file,$(prefix))
 
 tags:	force
@@ -310,6 +312,32 @@ all: $(DEFAULT_TARGET)
 $(bdir):
 	@mkdir -p $(bdir)
 
+VERSION = $(TFS_VERSION)
+PATCHLEVEL = $(TFS_PATCHLEVEL)
+EXTRAVERSION = $(TFS_EXTRAVERSION)
+
+define make_version.h
+  (echo '/* This file is automatically generated. Do not modify. */';		\
+   echo \#define VERSION_CODE $(shell						\
+   expr $(VERSION) \* 256 + $(PATCHLEVEL));					\
+   echo '#define EXTRAVERSION ' $(EXTRAVERSION);				\
+   echo '#define VERSION_STRING "'$(VERSION).$(PATCHLEVEL).$(EXTRAVERSION)'"';	\
+  ) > $1
+endef
+
+define update_version.h
+  ($(call make_version.h, $@.tmp);		\
+    if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
+      rm -f $@.tmp;				\
+    else					\
+      echo '  UPDATE             $@';		\
+      mv -f $@.tmp $@;				\
+    fi);
+endef
+
+$(VERSION_FILE): force
+	$(Q)$(call update_version.h)
+
 $(LIBTRACEFS_STATIC): force
 	$(Q)mkdir -p $(bdir)
 	$(Q)$(MAKE) -C $(src)/src $@
@@ -323,5 +351,6 @@ clean:
 	$(MAKE) -C $(src)/src clean
 	$(RM) $(TARGETS) $(bdir)/*.a $(bdir)/*.so $(bdir)/*.so.* $(bdir)/*.o $(bdir)/.*.d
 	$(RM) $(PKG_CONFIG_FILE)
+	$(RM) $(VERSION_FILE)
 
 .PHONY: clean
-- 
2.29.2