oe.external: move common functions here

Also provide external-common.bbclass to wrap its inclusion and setup
associated metadata. This will make easier to search sysroots for files
without pulling in the rest of the external toolchain class.

Signed-off-by: Christopher Larson <chris_larson@mentor.com>

conf/distro/include/external-run.inc

@@ -1,24 +0,0 @@
-def external_run(d, cmd, *args):
-    import subprocess
-
-    topdir = d.getVar('TMPDIR', True)
-    toolchain_path = d.getVar('EXTERNAL_TOOLCHAIN', True)
-    if toolchain_path:
-        target_prefix = d.getVar('EXTERNAL_TARGET_SYS', True) + '-'
-        path = os.path.join(toolchain_path, 'bin', target_prefix + cmd)
-        args = [path] + list(args)
-
-        try:
-            output = oe.path.check_output(args, cwd=topdir, stderr=subprocess.STDOUT)
-        except oe.path.CalledProcessError as exc:
-            import pipes
-            bb.debug(1, "{0} failed: {1}".format(' '.join(pipes.quote(a) for a in args), exc.output))
-        except OSError as exc:
-            import pipes
-            bb.debug(1, "{0} failed: {1}".format(' '.join(pipes.quote(a) for a in args), str(exc)))
-        else:
-            return output
-
-    return 'UNKNOWN'
-
-external_run[vardepsexclude] += "EXTERNAL_TOOLCHAIN TMPDIR"

conf/distro/include/tcmode-external-sourcery.inc

@@ -44,6 +44,9 @@ PREFERRED_PROVIDER_oprofile ??= "oprofile"
 PREFERRED_PROVIDER_libgcc = "libgcc-external"
 PREFERRED_PROVIDER_linux-libc-headers = "linux-libc-headers-external"
 
+# Pull in our utility functions for use elsewhere
+INHERIT += "external-common"
+
 # Ensure that we don't pull in any internal toolchain recipes
 INHERIT += "blacklist blacklist_dynamic"
 PNBLACKLIST[uclibc] = "not building with an external toolchain"
@@ -189,15 +192,13 @@ python toolchain_sanity_check () {
 toolchain_sanity_check[eventmask] = "bb.event.TreeDataPreparationStarted"
 addhandler toolchain_sanity_check
 
-require conf/distro/include/external-run.inc
-
 GCCVERSION ?= "${@'.'.join('${GCC_VERSION}'.split('.')[:2])}%"
 GCC_VERSION = "${@external_run(d, 'gcc', '-dumpversion').rstrip()}"
 GCC_VERSION_allarch = ""
 GCC_VERSION[vardepvalue] = "${GCC_VERSION}"
 
 def sourcery_version(d):
-    version = external_run(d, 'gcc', '-v').splitlines()[-1]
+    version = oe.external.run(d, 'gcc', '-v').splitlines()[-1]
     if version != 'UNKNOWN':
         main_version = version.split()[-1].rstrip(')')
         if main_version == 'Preview':