Bug 97954: Compare SpiderMonkey's copies of build files with originals at check time. r=luser

SpiderMonkey now has its own copy of some of the files from ./config
and ./build.  Since there is a decent amount of churn in that area, I
don't want it to become a burden to make merges back and forth.  This
patch adds a comment explaining the 'identical if present' policy, and
runs a script to verify that it's actually being observed.

configure.in

@@ -8289,6 +8289,7 @@ ac_configure_args="$ac_configure_args --with-nspr-libs='$NSPR_LIBS'"
 ac_configure_args="$ac_configure_args --includedir=$dist/include"
 ac_configure_args="$ac_configure_args --bindir=$dist/bin"
 ac_configure_args="$ac_configure_args --libdir=$dist/lib"
+ac_configure_args="$ac_configure_args --with-sync-build-files=$srcdir"
 if test "$MOZ_MEMORY"; then
    ac_configure_args="$ac_configure_args --enable-jemalloc"  
 fi

js/src/Makefile.in

@@ -333,6 +333,27 @@ endif
 
 include $(topsrcdir)/config/rules.mk
 
+ifdef MOZ_SYNC_BUILD_FILES
+# Because the SpiderMonkey can be distributed and built independently
+# of the Mozilla source tree, it contains its own copies of many of
+# the files used by the top-level Mozilla build process, from the
+# 'config' and 'build' subtrees.
+#
+# To make it simpler to keep the copies in sync, we follow the policy
+# that the SpiderMonkey copies must always be exact copies of those in
+# the containing Mozilla tree.  If you've made a change in one, it
+# belongs in the other as well.  If the change isn't right for both
+# places, then that's something to bring up with the other developers.
+#
+# Some files are reasonable to diverge; for example,
+# js/config/autoconf.mk.in doesn't need most of the stuff in
+# config/autoconf.mk.in.
+check-sync-dirs = $(PYTHON) $(srcdir)/config/check-sync-dirs.py
+check::
+	$(check-sync-dirs) $(srcdir)/config $(MOZ_SYNC_BUILD_FILES)/config
+	$(check-sync-dirs) $(srcdir)/build $(MOZ_SYNC_BUILD_FILES)/build
+endif
+
 # our build system doesn't handle subdir srcs very gracefully today
 export::
 	mkdir -p nanojit

js/src/config/autoconf.mk.in

@@ -68,6 +68,8 @@ DIST		= $(DEPTH)/dist
 
 MOZ_JS_LIBS		   = @MOZ_JS_LIBS@
 
+MOZ_SYNC_BUILD_FILES = @MOZ_SYNC_BUILD_FILES@
+
 MOZ_DEBUG	= @MOZ_DEBUG@
 MOZ_DEBUG_MODULES = @MOZ_DEBUG_MODULES@
 MOZ_PROFILE_MODULES = @MOZ_PROFILE_MODULES@

js/src/config/check-sync-dirs.py

@@ -0,0 +1,108 @@
+# check-sync-dirs.py --- check that one directory is an exact subset of another
+#
+# Usage: python check-sync-dirs.py COPY ORIGINAL
+#
+# Check that the files present in the directory tree COPY are exact
+# copies of their counterparts in the directory tree ORIGINAL.  COPY
+# need not have all the files in ORIGINAL, but COPY may not have files
+# absent from ORIGINAL.
+# 
+# Each directory in COPY may have a file named
+# 'check-sync-exceptions', which lists files in COPY that need not be
+# the same as the corresponding file in ORIGINAL, or exist at all in
+# ORIGINAL.  (The 'check-sync-exceptions' file itself is always
+# treated as exceptional.)  Blank lines and '#' comments in the file
+# are ignored.
+
+import sys
+import os
+from os.path import join
+import filecmp
+import textwrap
+import fnmatch
+
+if len(sys.argv) != 3:
+    print >> sys.stderr, "Usage: %s COPY ORIGINAL" % sys.argv[0]
+    sys.exit(1)
+
+copy = sys.argv[1]
+original = sys.argv[2]
+
+# Ignore detritus left lying around by editing tools.
+ignored_patterns = ['*~', '.#*', '#*#', '*.orig', '*.rej']
+
+# Return the contents of FILENAME, a 'check-sync-exceptions' file, as
+# a dictionary whose keys are exactly the list of filenames, along
+# with the basename of FILENAME itself.  If FILENAME does not exist,
+# return the empty dictionary.
+def read_exceptions(filename):
+    if (os.path.exists(filename)):
+        f = file(filename)
+        exceptions={}
+        for line in f:
+            line = line.strip()
+            if line != '' and line[0] != '#':
+                exceptions[line] = None
+        exceptions[os.path.basename (filename)] = None
+        f.close()
+        return exceptions
+    else:
+        return {}
+
+# Return true if FILENAME matches any pattern in the list of filename
+# patterns PATTERNS.
+def fnmatch_any(filename, patterns):
+    for pattern in patterns:
+        if fnmatch.fnmatch(filename, pattern):
+            return True
+    return False
+
+# Check the contents of COPY/SUBDIR against ORIGINAL/SUBDIR.  For each
+# file that differs, apply REPORT to COPY, ORIGINAL, and the file's
+# relative path.  COPY and ORIGINAL should be absolute.  Ignore files 
+# that match patterns given in the list IGNORE.
+def check(copy, original, ignore, report):
+    os.chdir(copy)
+    for (dirpath, dirnames, filenames) in os.walk('.'):
+        exceptions = read_exceptions(join(dirpath, 'check-sync-exceptions'))
+        for filename in filenames:
+            if filename in exceptions:
+                continue
+            if fnmatch_any(filename, ignore):
+                continue
+            relative_name = join(dirpath, filename)
+            original_name = join(original, relative_name)
+            if (os.path.exists(original_name)
+                and filecmp.cmp(relative_name, original_name)):
+                continue
+            report(copy, original, relative_name)
+
+
+differences_found = False
+
+# Print an error message for DIFFERING, which was found to differ
+# between COPY and ORIGINAL.  Set the global variable differences_found.
+def report(copy, original, differing):
+    global differences_found
+    if not differences_found:
+        print >> sys.stderr, "TEST-FAIL | build file copies are not in sync"
+        print >> sys.stderr, "file(s) found in:               %s" % (copy)
+        print >> sys.stderr, ("differ from their originals in: %s"
+                              % (original))
+    print >> sys.stderr, "file differs: %s" % (differing)
+    differences_found = True
+
+check(os.path.abspath(copy),
+      os.path.abspath(original),
+      ignored_patterns,
+      report)
+
+if differences_found:
+    msg=('''In general, the files in '%s' should always be exact copies of
+originals in '%s'.  A change made to one should also be made to the
+other.  See 'check-sync-dirs.py' for more details.'''
+         % (copy, original))
+    print >> sys.stderr, textwrap.fill(msg, 75)
+    sys.exit(1)
+
+sys.exit(0)

js/src/config/check-sync-exceptions

@@ -0,0 +1,6 @@
+Makefile.in
+autoconf.mk.in
+check-sync-dirs.py
+
+# This is a copy of nspr's config/make-system-wrappers.pl.
+make-system-wrappers.pl

js/src/configure.in

@@ -103,11 +103,7 @@ _SUBDIR_CONFIG_ARGS="$ac_configure_args"
 
 dnl Set the version number of the libs included with mozilla
 dnl ========================================================
-MOZJPEG=62
-MOZPNG=10217
-MOZZLIB=0x1230
 NSPR_VERSION=4
-NSS_VERSION=3
 
 dnl Set the minimum version of toolkit libs used by mozilla
 dnl ========================================================
@@ -1977,8 +1973,6 @@ case "$target" in
             fi
         fi
     fi
-    MOZ_JPEG_LIBS='$(call EXPAND_LIBNAME_PATH,jpeg$(MOZ_BITS)$(VERSION_NUMBER),$(DEPTH)/jpeg)'
-    MOZ_PNG_LIBS='$(call EXPAND_LIBNAME_PATH,png,$(DEPTH)/modules/libimg/png)'
     AC_DEFINE(HAVE_SNPRINTF)
     AC_DEFINE(_WINDOWS)
     AC_DEFINE(_WIN32)
@@ -4831,6 +4825,15 @@ if test "$MOZ_DEBUG" || test "$NS_TRACE_MALLOC"; then
     MOZ_COMPONENTS_VERSION_SCRIPT_LDFLAGS=
 fi
 
+MOZ_ARG_WITH_STRING(sync-build-files,
+[  --with-sync-build-files=DIR
+                          Check that files in 'config' and 'build' match
+                          their originals in 'DIR/config' and 'DIR/build'.
+                          This helps keep the SpiderMonkey build machinery
+                          in sync with Mozilla's, on which it is based.],
+[MOZ_SYNC_BUILD_FILES=$withval ] )
+AC_SUBST(MOZ_SYNC_BUILD_FILES)
+
 dnl ========================================================
 dnl =
 dnl = Maintainer debug option (no --enable equivalent)

nsprpub/configure

@@ -6016,7 +6016,7 @@ s%\[%\\&%g
 s%\]%\\&%g
 s%\$%$$%g
 EOF
-DEFS=`sed -f conftest.defs confdefs.h | tr '\012' ' ' | tr '\015' ' '`
+DEFS=`sed -f conftest.defs confdefs.h | tr '\012' ' '`
 rm -f conftest.defs