bitbake: Add a --revisions-changed commandline option to indicate when floating srcrevs have changed

Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

bitbake/bin/bitbake

@@ -108,6 +108,9 @@ Default BBFILES are the .bb files in the current directory.""" )
     parser.add_option( "-P", "--profile", help = "profile the command and print a report",
                action = "store_true", dest = "profile", default = False )
 
+    parser.add_option( "", "--revisions-changed", help = "Set the exit code depending on whether upstream floating revisions have changed or not",
+               action = "store_true", dest = "revisions_changed", default = False )
+
     options, args = parser.parse_args(sys.argv)
 
     configuration = BBConfiguration(options)

bitbake/lib/bb/cooker.py

@@ -612,6 +612,9 @@ class BBCooker:
         # initialise the parsing status now we know we will need deps
         self.updateCache()
 
+        if self.configuration.revisions_changed:
+            sys.exit(bb.fetch.fetcher_compare_revisons(self.configuration.data))
+
         if self.configuration.parse_only:
             bb.msg.note(1, bb.msg.domain.Collection, "Requested parsing .bb files only.  Exiting.")
             return 0

bitbake/lib/bb/fetch/__init__.py

@@ -97,13 +97,34 @@ def fetcher_init(d):
         bb.msg.debug(1, bb.msg.domain.Fetcher, "Keeping SRCREV cache due to cache policy of: %s" % srcrev_policy)
     elif srcrev_policy == "clear":
         bb.msg.debug(1, bb.msg.domain.Fetcher, "Clearing SRCREV cache due to cache policy of: %s" % srcrev_policy)
-        pd.delDomain("BB_URI_HEADREVS")
+        pd.renameDomain("BB_URI_HEADREVS", "BB_URI_HEADREVS_PREVIOUS")
     else:
         bb.msg.fatal(bb.msg.domain.Fetcher, "Invalid SRCREV cache policy of: %s" % srcrev_policy)
     # Make sure our domains exist
     pd.addDomain("BB_URI_HEADREVS")
+    pd.addDomain("BB_URI_HEADREVS_PREVIOUS")
     pd.addDomain("BB_URI_LOCALCOUNT")
 
+def fetcher_compare_revisons(d):
+    """
+    Compare the revisions in the persistant cache with current values and
+    return true/false on whether they've changed.
+    """
+
+    pd = persist_data.PersistData(d)
+    data = pd.getKeyValues("BB_URI_HEADREVS")
+    data2 = pd.getKeyValues("BB_URI_HEADREVS_PREVIOUS")
+
+    changed = False
+    for key in data:
+        if key not in data2 or data2[key] != data[key]:
+            bb.msg.debug(1, bb.msg.domain.Fetcher, "%s changed" % key)
+            changed = True
+            return True
+        else:
+            bb.msg.debug(2, bb.msg.domain.Fetcher, "%s did not change" % key)
+    return False
+
 # Function call order is usually:
 #   1. init
 #   2. go