classes/gitpkgv.bbclass: add GITPKGVTAG that uses 'git describe'

Using ${GITPKGVTAG} allows for automatic versioning based on the
repository tags. For those that doesn't want to use it, ${GITPKGV} is
still available.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Acked-by: Martin Jansa <Martin.Jansa@gmail.com>

1 files changed, 53 insertions, 13 deletions

diff --git a/classes/gitpkgv.bbclass b/classes/gitpkgv.bbclass
index bc1dc32561..64adcae9ad 100644
--- a/classes/gitpkgv.bbclass
+++ b/classes/gitpkgv.bbclass
@@ -1,23 +1,53 @@
-# gitpkgv.bbclass provides a GITPKGV variable which is a sortable version
-# with the format NN+GITHASH, to be used in PKGV, where
+# gitpkgv.bbclass provides a GITPKGV and GITPKGVTAG variables to be
+# used in PKGV, as described bellow:
 #
-# NN equals the total number of revs up to SRCREV
-# GITHASH is SRCREV's (full) hash
+# - GITPKGV which is a sortable version with the format NN+GITHASH, to
+#   be used in PKGV, where
 #
-# gitpkgv.bbclass assumes the git repository has been cloned, and contains
-# SRCREV. So ${GITPKGV} should never be used in PV, only in PKGV.
-# It can handle SRCREV = ${AUTOREV}, as well as SRCREV = "<some fixed git hash>"
+#   NN equals the total number of revs up to SRCREV
+#   GITHASH is SRCREV's (full) hash
+#
+# - GITPKGVTAG which is the output of 'git describe' allowing for
+#   automatic versioning
+#
+# gitpkgv.bbclass assumes the git repository has been cloned, and
+# contains SRCREV. So ${GITPKGV} and ${GITPKGVTAG} should never be
+# used in PV, only in PKGV.  It can handle SRCREV = ${AUTOREV}, as
+# well as SRCREV = "<some fixed git hash>".
+#
+# WARNING: if upstream repository is always using consistent and
+# sortable tag name scheme you can get sortable version including tag
+# name with ${GITPKGVTAG}, but be aware that ie tag sequence "v1.0,
+# v1.2, xtest, v2.0" will force you to increment PE to get upgradeable
+# path to v2.0 revisions
 #
 # use example:
 #
 # inherit gitpkgv
 #
-# PV = "1.0+git${SRCPV}"
-# PKGV = "1.0+git${GITPKGV}"
+# PV = "1.0+gitr${SRCPV}"      # expands to something like 1.0+gitr3+4c1c21d7dbbf93b0df336994524313dfe0d4963b
+# PKGV = "1.0+gitr${GITPKGV}"  # expands also to something like 1.0+gitr31337+4c1c21d7d
+#
+# or
+#
+# inherit gitpkgv
+#
+# PV = "1.0+gitr${SRCPV}" # expands to something like 1.0+gitr3+4c1c21d7dbbf93b0df336994524313dfe0d4963b
+# PKGV = "${GITPKGVTAG}"  # expands to something like 1.0-31337+g4c1c21d
+#                           if there is tag v1.0 before this revision or
+#                           ver1.0-31337+g4c1c21d if there is tag ver1.0
+
+GITPKGV = "${@get_git_pkgv(d, False)}"
+GITPKGVTAG = "${@get_git_pkgv(d, True)}"
 
-GITPKGV = "${@get_git_pkgv(d)}"
+def git_drop_tag_prefix(version):
+    import re
+    if re.match("v\d", version):
+        return version[1:]
+    else:
+        return version
 
-def get_git_pkgv(d):
+def get_git_pkgv(d, use_tags):
 	import os
 	import bb
 
@@ -33,9 +63,19 @@ def get_git_pkgv(d):
 
 			cwd = os.getcwd()
 			os.chdir(repodir)
-			output = bb.fetch.runfetchcmd("git rev-list %s -- 2> /dev/null | wc -l" % rev, d, quiet=True)
+
+			commits = bb.fetch.runfetchcmd("git rev-list %s -- 2> /dev/null | wc -l" % rev, d, quiet=True).strip()
+
+			if use_tags:
+				try:
+					ver = git_drop_tag_prefix(bb.fetch.runfetchcmd("git describe %s 2>/dev/null" % rev, d, quiet=True).strip())
+				except Exception:
+					ver = "0.0-%s-g%s" % (commits, rev[:7])
+			else:
+				ver = "%s+%s" % (commits, rev[:7])
+
 			os.chdir(cwd)
 
-			return "%s+%s" % (output.split()[0], rev)
+			return ver
 
 	return "0+0"