package.bbclass: Fix base directory for debugsource files when using externalsrc

While executing do_package, bitbake checks for a list of
debug source files and uses a pattern to match the ones
to be included in copydebugsources.

Previously when externalsrc was in use either directly or by
using devtool, the source location changed and this pattern
no longer matched, hence debug source files failed to be
included in the corresponding package.

Check when the source directory isnt the default (based on
WORKDIR), and change the pattern used to match debug source
files if that is the case, allowing us to perform do_package
properly.

Workaround debugsource.list containing paths from the host by
moving debug source files away from the host directory
structure  to avoid host contamination (this seems to happen
when packages use $TMPDIR/work-shared and externalsrc is
in use).

Test matrix included using:
- devtool to use externalsrc automatically
- externalsrc with a non-devtool based source directory
- No externalsrc at all
Tested the following packages to be working:
- glibc ($TMPDIR/work-shared based)
- libxcrypt ($TMPDIR/work based)

[YOCTO 8015]

(From OE-Core rev: a887bd96fd0a15398e8077ea79df5070971866e4)

Signed-off-by: Alejandro Enedino Hernandez Samaniego <alhe@linux.microsoft.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/package.bbclass

@@ -553,13 +553,25 @@ def copydebugsources(debugsrcdir, sources, d):
         strip = d.getVar("STRIP")
         objcopy = d.getVar("OBJCOPY")
         workdir = d.getVar("WORKDIR")
+        sdir = d.getVar("S")
+        sparentdir = os.path.dirname(os.path.dirname(sdir))
+        sbasedir = os.path.basename(os.path.dirname(sdir)) + "/" + os.path.basename(sdir)
         workparentdir = os.path.dirname(os.path.dirname(workdir))
         workbasedir = os.path.basename(os.path.dirname(workdir)) + "/" + os.path.basename(workdir)
 
+        # If S isnt based on WORKDIR we can infer our sources are located elsewhere,
+        # e.g. using externalsrc; use S as base for our dirs
+        if workdir in sdir:
+            basedir = workbasedir
+            parentdir = workparentdir
+        else:
+            basedir = sbasedir
+            parentdir = sparentdir
+
         # If build path exists in sourcefile, it means toolchain did not use
         # -fdebug-prefix-map to compile
         if checkbuildpath(sourcefile, d):
-            localsrc_prefix = workparentdir + "/"
+            localsrc_prefix = parentdir + "/"
         else:
             localsrc_prefix = "/usr/src/debug/"
 
@@ -581,7 +593,7 @@ def copydebugsources(debugsrcdir, sources, d):
         processdebugsrc += "sed 's#%s##g' | "
         processdebugsrc += "(cd '%s' ; cpio -pd0mlL --no-preserve-owner '%s%s' 2>/dev/null)"
 
-        cmd = processdebugsrc % (sourcefile, workbasedir, localsrc_prefix, workparentdir, dvar, debugsrcdir)
+        cmd = processdebugsrc % (sourcefile, basedir, localsrc_prefix, parentdir, dvar, debugsrcdir)
         try:
             subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
         except subprocess.CalledProcessError:
@@ -591,9 +603,22 @@ def copydebugsources(debugsrcdir, sources, d):
         # cpio seems to have a bug with -lL together and symbolic links are just copied, not dereferenced.
         # Work around this by manually finding and copying any symbolic links that made it through.
         cmd = "find %s%s -type l -print0 -delete | sed s#%s%s/##g | (cd '%s' ; cpio -pd0mL --no-preserve-owner '%s%s')" % \
-                (dvar, debugsrcdir, dvar, debugsrcdir, workparentdir, dvar, debugsrcdir)
+                (dvar, debugsrcdir, dvar, debugsrcdir, parentdir, dvar, debugsrcdir)
         subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
 
+
+        # debugsources.list may be polluted from the host if we used externalsrc,
+        # cpio uses copy-pass and may have just created a directory structure
+        # matching the one from the host, if thats the case move those files to
+        # debugsrcdir to avoid host contamination.
+        # Empty dir structure will be deleted in the next step.
+
+        # Same check as above for externalsrc
+        if workdir not in sdir:
+            if os.path.exists(dvar + debugsrcdir + sdir):
+                cmd = "mv %s%s%s/* %s%s" % (dvar, debugsrcdir, sdir, dvar,debugsrcdir)
+                subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+
         # The copy by cpio may have resulted in some empty directories!  Remove these
         cmd = "find %s%s -empty -type d -delete" % (dvar, debugsrcdir)
         subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)