base/bitbake.conf: Introduce UNPACKDIR

Having the unpack directory hardcoded to WORKDIR makes it really hard to
make any changes to the unpack process to try and allow for cleanup for example.

As a first step toward unraveling the intertwined location usages, add a
variable, UNPACKDIR which is where the fetcher is asked to unpack fetched
sources. It defaults to the existing value of WORKDIR at this point.

(From OE-Core rev: e022d62ba917790af2121da57646271ef17c03fa)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes-global/base.bbclass

@@ -153,7 +153,7 @@ python base_do_fetch() {
 }
 
 addtask unpack after do_fetch
-do_unpack[dirs] = "${WORKDIR}"
+do_unpack[dirs] = "${UNPACKDIR}"
 
 do_unpack[cleandirs] = "${@d.getVar('S') if os.path.normpath(d.getVar('S')) != os.path.normpath(d.getVar('WORKDIR')) else os.path.join('${S}', 'patches')}"
 
@@ -164,7 +164,7 @@ python base_do_unpack() {
 
     try:
         fetcher = bb.fetch2.Fetch(src_uri, d)
-        fetcher.unpack(d.getVar('WORKDIR'))
+        fetcher.unpack(d.getVar('UNPACKDIR'))
     except bb.fetch2.BBFetchException as e:
         bb.fatal("Bitbake Fetcher Error: " + repr(e))
 }

meta/conf/bitbake.conf

@@ -405,6 +405,7 @@ STAMP = "${STAMPS_DIR}/${MULTIMACH_TARGET_SYS}/${PN}/${PV}"
 STAMPCLEAN = "${STAMPS_DIR}/${MULTIMACH_TARGET_SYS}/${PN}/*-*"
 BASE_WORKDIR ?= "${TMPDIR}/work"
 WORKDIR = "${BASE_WORKDIR}/${MULTIMACH_TARGET_SYS}/${PN}/${PV}"
+UNPACKDIR ??= "${WORKDIR}"
 T = "${WORKDIR}/temp"
 D = "${WORKDIR}/image"
 S = "${WORKDIR}/${BP}"

meta/lib/oe/reproducible.py

@@ -120,7 +120,7 @@ def get_source_date_epoch_from_git(d, sourcedir):
     return int(p.stdout.decode('utf-8'))
 
 def get_source_date_epoch_from_youngest_file(d, sourcedir):
-    if sourcedir == d.getVar('WORKDIR'):
+    if sourcedir == d.getVar('UNPACKDIR'):
        # These sources are almost certainly not from a tarball
        return None