1 files changed, 29 insertions, 5 deletions

diff --git a/scripts/oe-depends-dot b/scripts/oe-depends-dot
index 5eb3e12769..d02ee455f6 100755
--- a/scripts/oe-depends-dot
+++ b/scripts/oe-depends-dot
@@ -14,8 +14,8 @@ import re
 class Dot(object):
     def __init__(self):
         parser = argparse.ArgumentParser(
-            description="Analyse recipe-depends.dot generated by bitbake -g",
-            epilog="Use %(prog)s --help to get help")
+            description="Analyse task-depends.dot generated by bitbake -g",
+            formatter_class=argparse.RawDescriptionHelpFormatter)
         parser.add_argument("dotfile",
             help = "Specify the dotfile", nargs = 1, action='store', default='')
         parser.add_argument("-k", "--key",
@@ -32,6 +32,21 @@ class Dot(object):
                     " For example, A->B, B->C, A->C, then A->C can be removed.",
             action="store_true", default=False)
 
+        parser.epilog = """
+Examples:
+First generate the .dot file:
+    bitbake -g core-image-minimal
+
+To find out why a package is being built:
+    %(prog)s -k <package> -w ./task-depends.dot
+
+To find out what a package depends on:
+    %(prog)s -k <package> -d ./task-depends.dot
+
+Reduce the .dot file packages only, no tasks:
+    %(prog)s -r ./task-depends.dot
+"""
+
         self.args = parser.parse_args()
 
         if len(sys.argv) != 3 and len(sys.argv) < 5:
@@ -99,6 +114,10 @@ class Dot(object):
                 if key == "meta-world-pkgdata":
                     continue
                 dep = m.group(2)
+                key = key.split('.')[0]
+                dep = dep.split('.')[0]
+                if key == dep:
+                    continue
                 if key in depends:
                     if not key in depends[key]:
                         depends[key].add(dep)
@@ -140,9 +159,14 @@ class Dot(object):
 
         reverse_deps = []
         if self.args.why:
-            for k, v in depends.items():
-                if self.args.key in v and not k in reverse_deps:
-                    reverse_deps.append(k)
+            key_list = [self.args.key]
+            current_key = self.args.key
+            while (len(key_list) != 0):
+                current_key = key_list.pop()
+                for k, v in depends.items():
+                    if current_key in v and not k in reverse_deps:
+                        reverse_deps.append(k)
+                        key_list.append(k)
             print('Because: %s' % ' '.join(reverse_deps))
             Dot.print_dep_chains(self.args.key, reverse_deps, depends)