bitbake: fetch2: unify the way fetchers determine DL_DIR and FETCHCMD

Currently there is quite some variation between the fetchers in terms
of how they determine the subdirectory within DL_DIR and the base
fetch command to run. Some rely on variables being set externally
(e.g. from bitbake.conf in oe-core), some respect these external
variables but provide fallback defaults and some use only hardcoded
internal values. Try to unify the approach used across the various
fetchers.

(Bitbake rev: efd5e35af4b08501c67e8b30f30d9457f6fdf610)

Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/cvs.py

@@ -110,7 +110,7 @@ class Cvs(FetchMethod):
         if ud.tag:
             options.append("-r %s" % ud.tag)
 
-        cvsbasecmd = d.getVar("FETCHCMD_cvs")
+        cvsbasecmd = d.getVar("FETCHCMD_cvs") or "/usr/bin/env cvs"
         cvscmd = cvsbasecmd + " '-d" + cvsroot + "' co " + " ".join(options) + " " + ud.module
         cvsupdatecmd = cvsbasecmd + " '-d" + cvsroot + "' update -d -P " + " ".join(options)
 
@@ -121,7 +121,8 @@ class Cvs(FetchMethod):
         # create module directory
         logger.debug(2, "Fetch: checking for module directory")
         pkg = d.getVar('PN')
-        pkgdir = os.path.join(d.getVar('CVSDIR'), pkg)
+        cvsdir = d.getVar("CVSDIR") or (d.getVar("DL_DIR") + "/cvs")
+        pkgdir = os.path.join(cvsdir, pkg)
         moddir = os.path.join(pkgdir, localdir)
         workdir = None
         if os.access(os.path.join(moddir, 'CVS'), os.R_OK):