package.bbclass: Preserve hard links!

Hard links were not being preserved in the move from the install image
-> package copy.  Again they were being discarded in the package ->
packages-split copy as well.

By preserving the hard links we have the potential to save a ton of rootfs
space.

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>

diff --git a/meta/classes/package.bbclass b/meta/classes/package.bbclass
index 8f58ad03f10bd90dd8f86d874db3fa9ec8b9797d..0698f6451550fce1c4c59f81b775b3c38b8197c4 100644 (file)
--- a/meta/classes/package.bbclass
+++ b/meta/classes/package.bbclass
@@ -323,7 +323,8 @@ python perform_packagecopy () {
        # Start by package population by taking a copy of the installed 
        # files to operate on
        os.system('rm -rf %s/*' % (dvar))
-       os.system('cp -pPR %s/* %s/' % (dest, dvar))
+       # Preserve sparse files and hard links
+       os.system('tar -cf - -C %s -ps . | tar -xf - -C %s' % (dest, dvar))
 }
 
 python populate_packages () {
@@ -383,6 +384,7 @@ python populate_packages () {
 
                filesvar = bb.data.getVar('FILES', localdata, True) or ""
                files = filesvar.split()
+               file_links = {}
                for file in files:
                        if os.path.isabs(file):
                                file = '.' + file
@@ -406,9 +408,23 @@ python populate_packages () {
                                bb.mkdirhier(os.path.join(root,file))
                                os.chmod(os.path.join(root,file), os.stat(file).st_mode)
                                continue
+
                        fpath = os.path.join(root,file)
                        dpath = os.path.dirname(fpath)
                        bb.mkdirhier(dpath)
+
+                       # Check if this is a hardlink to something... if it is
+                       # attempt to preserve the link information, instead of copy.
+                       if not os.path.islink(file):
+                               s = os.stat(file)
+                               if s.st_nlink > 1:
+                                       file_reference = "%d_%d" % (s.st_dev, s.st_ino)
+                                       if file_reference not in file_links:
+                                               # Save the reference for next time...
+                                               file_links[file_reference] = fpath
+                                       else:
+                                               os.link(file_links[file_reference], fpath)
+                                               continue
                        ret = bb.copyfile(file, fpath)
                        if ret is False or ret == 0:
                                raise bb.build.FuncFailed("File population failed")