package: Switch debug source handling to use prefix map

Reproducible builds are no longer a configuration option but are required.
We also rely on the prefix mapping capability of the compilers now.

As such, rewrite the source locating code to use the prefix maps instead
of taking a guess about WORKDIR which isn't correct for kernels, gcc,
externalsrc and probably more.

Instead, iterate the maps to locate any matching source code, keeping
in mind that multiple maps may map to one target location.

(From OE-Core rev: 80289f49d0c5ca98da1d1558728b8a468aab4326)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit cbd6144a9769d21371ae0fe04db2adc05f6eed02)
Signed-off-by: Steve Sakoman <steve@sakoman.com>

meta/classes/package.bbclass

@@ -574,26 +574,16 @@ def copydebugsources(debugsrcdir, sources, d):
         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)
+        cflags = d.expand("${CFLAGS}")
 
-        # 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 or 'work-shared' 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 = parentdir + "/"
-        else:
-            localsrc_prefix = "/usr/src/debug/"
+        prefixmap = {}
+        for flag in cflags.split():
+            if not flag.startswith("-fdebug-prefix-map"):
+                continue
+            if "recipe-sysroot" in flag:
+                continue
+            flag = flag.split("=")
+            prefixmap[flag[1]] = flag[2]
 
         nosuchdir = []
         basepath = dvar
@@ -604,28 +594,26 @@ def copydebugsources(debugsrcdir, sources, d):
         bb.utils.mkdirhier(basepath)
         cpath.updatecache(basepath)
 
-        # Ignore files from the recipe sysroots (target and native)
-        processdebugsrc =  "LC_ALL=C ; sort -z -u '%s' | egrep -v -z '((<internal>|<built-in>)$|/.*recipe-sysroot.*/)' | "
-        # We need to ignore files that are not actually ours
-        # we do this by only paying attention to items from this package
-        processdebugsrc += "fgrep -zw '%s' | "
-        # Remove prefix in the source paths
-        processdebugsrc += "sed 's#%s##g' | "
-        processdebugsrc += "(cd '%s' ; cpio -pd0mlL --no-preserve-owner '%s%s' 2>/dev/null)"
+        for pmap in prefixmap:
+            # Ignore files from the recipe sysroots (target and native)
+            cmd =  "LC_ALL=C ; sort -z -u '%s' | egrep -v -z '((<internal>|<built-in>)$|/.*recipe-sysroot.*/)' | " % sourcefile
+            # We need to ignore files that are not actually ours
+            # we do this by only paying attention to items from this package
+            cmd += "fgrep -zw '%s' | " % prefixmap[pmap]
+            # Remove prefix in the source paths
+            cmd += "sed 's#%s/##g' | " % (prefixmap[pmap])
+            cmd += "(cd '%s' ; cpio -pd0mlL --no-preserve-owner '%s%s' 2>/dev/null)" % (pmap, dvar, prefixmap[pmap])
 
-        cmd = processdebugsrc % (sourcefile, basedir, localsrc_prefix, parentdir, dvar, debugsrcdir)
-        try:
+            try:
+                subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
+            except subprocess.CalledProcessError:
+                # Can "fail" if internal headers/transient sources are attempted
+                pass
+            # 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, prefixmap[pmap], dvar, prefixmap[pmap], pmap, dvar, prefixmap[pmap])
             subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT)
-        except subprocess.CalledProcessError:
-            # Can "fail" if internal headers/transient sources are attempted
-            pass
-
-        # 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, 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