archiver.bbclass: ignore unpack sub-directories in do_ar_original

Support for absolute paths in the "subdir" parameter was recently
added (bitbake rev: c3873346c6fa). The git fetcher has supported
absolute paths in "destsuffix" already before.

When the path is absolute as in destsuffix=${S}/foobar, the tmpdir
used by do_ar_original gets ignored, which breaks:
- source code archiving (tmpdir is empty)
- compilation due to race conditions (for example, ${S} getting
  modified by do_ar_original while do_compile runs)

To solve this, these parameters get removed from URLs before
instantiating the fetcher for them.

This is done unconditionally also for relative paths, because these
paths are not useful when archiving the original source (upstream
source does not have them, they only get used by the recipe during
compilation).

(From OE-Core rev: c27c464e267db3f4b08cbd966412d19b0e756d28)

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/archiver.bbclass

@@ -132,7 +132,25 @@ python do_ar_original() {
 
     ar_outdir = d.getVar('ARCHIVER_OUTDIR', True)
     bb.note('Archiving the original source...')
-    fetch = bb.fetch2.Fetch([], d)
+    urls = d.getVar("SRC_URI", True).split()
+    # destsuffix (git fetcher) and subdir (everything else) are allowed to be
+    # absolute paths (for example, destsuffix=${S}/foobar).
+    # That messes with unpacking inside our tmpdir below, because the fetchers
+    # will then unpack in that directory and completely ignore the tmpdir.
+    # That breaks parallel tasks relying on ${S}, like do_compile.
+    #
+    # To solve this, we remove these parameters from all URLs.
+    # We do this even for relative paths because it makes the content of the
+    # archives more useful (no extra paths that are only used during
+    # compilation).
+    for i, url in enumerate(urls):
+        decoded = bb.fetch2.decodeurl(url)
+        for param in ('destsuffix', 'subdir'):
+            if param in decoded[5]:
+                del decoded[5][param]
+        encoded = bb.fetch2.encodeurl(decoded)
+        urls[i] = encoded
+    fetch = bb.fetch2.Fetch(urls, d)
     for url in fetch.urls:
         local = fetch.localpath(url).rstrip("/");
         if os.path.isfile(local):