Add a script to draw a dependency graph from a set of hpkg files

Useful for understanding dependency chains.

Change-Id: I64113ff87fe3cef2f45796b064749e0c6a5bf880

3rdparty/pulkomandy/pkggraph.py

@@ -0,0 +1,82 @@
+#!python3
+#
+# Copyright 2019-2023 Adrien Destugues <pulkomandy@pulkomandy.tk>
+#
+# Distributed under terms of the MIT license.
+
+from os import listdir
+from os.path import isfile, join
+import subprocess
+import re
+import sys
+
+"""
+Generate a graph of dependencies for a set of packages packages in an Haiku system.
+
+Usage:
+- Without arguments: generate a graph of all packages in /system/packages. This can be quite busy
+  and hard to understand. It will also take a while to generate the graph, as dot tries to route
+  thousands of edges.
+- With arguments: the arguments are a list of packages to analyze. This allows to print a subset
+  of the packages for a better view.
+
+Dependencies are resolved: if a package has a specific string in its REQUIRES and another has the
+same string in its PROVIDES, a BLUE edge is drawn between the two package.
+If a package has a REQUIRES that is not matched by any other package in the set, this REQUIRE entry
+is drawn as a node, and the edge pointing to it is RED (so you can easily see missing dependencies
+in a package subset). If you use the complete /system/packages hierarchy, there should be no red
+edges, all dependencies are satisfied.
+
+The output of the script can be saved to a file for manual analysis (for example, you can search
+packages that nothing points to, and see if you want to uninstall them), or piped into dot for
+rendering as a PNG, for example:
+
+    cd /system/packages
+    pkggraph.py qt* gst_plugins_ba* | dot -Tpng -o /tmp/packages.png
+    ShowImage /tmp/packages.png
+"""
+
+path = "/system/packages"
+if len(sys.argv) > 1:
+    packages = sys.argv[1:]
+else:
+    packages = [join(path, f) for f in listdir(path) if(isfile(join(path, f)))]
+
+print('strict digraph {\nrankdir="LR"\nsplines=ortho\nnode [ fontname="Noto", fontsize=10];')
+
+pmap = {}
+rmap = {}
+
+for p in packages:
+    pkgtool = subprocess.Popen(['package', 'list', '-i', p], stdout = subprocess.PIPE)
+    infos, stderr = pkgtool.communicate()
+
+    provides = []
+    requires = []
+
+    for line in infos.split(b'\n'):
+        if line.startswith(b"\tprovides:"):
+            provides.append(line.split(b' ')[1])
+        if line.startswith(b"\trequires:"):
+            line = line.split(b' ')[1]
+            if b'>' in line:
+                line = line.split(b'>')[0]
+            if b'=' in line:
+                line = line.split(b'=')[0]
+            if line != b'haiku' and line != b'haiku_x86':
+                requires.append(line)
+
+    for pro in provides:
+        pmap[pro] = provides[0]
+    if len(requires) > 0:
+        rmap[provides[0]] = requires
+
+for k,v in rmap.items():
+    for dep in v:
+        color = "red"
+        if dep in pmap:
+            dep = pmap[dep]
+            color = "blue"
+        print('"%s" -> "%s" [color=%s]' % (k.decode('utf-8'), dep.decode('utf-8'), color))
+
+print("}")