1 files changed, 48 insertions, 0 deletions
diff --git a/find-deps.py b/find-deps.py
new file mode 100755
index 000000000000..92095f934cfd
--- /dev/null
+++ b/find-deps.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python3
+
+"""
+Usage: find-deps.py <binary> [<binary> ...]
+
+Finds (pacman/ALPM) dependencies for a binary or set of binaries based
+on dynamically linked libraries.
+
+"""
+
+import sys
+import os
+import subprocess
+import re
+
+def subprocess_get_lines(args, fail_okay=False):
+    try:
+        output = subprocess.check_output(args)
+    except subprocess.CalledProcessError as e:
+        if fail_okay:
+            output = e.output
+        else:
+            raise
+    return output.decode().splitlines()
+
+# Get the filenames of the libs we need
+#del os.environ['LD_PRELOAD'] # otherwise fakeroot will interfere
+ldd_output = subprocess_get_lines(['ldd'] + sys.argv[1:])
+regex = re.compile(r' => (.*) \(0x[0-9a-f]+\)$')
+libs = set(match.group(1) for match in map(regex.search, ldd_output) if match)
+
+# Figure out which packages own them
+deps = set(subprocess_get_lines(
+    ['pacman', '--query', '--owns', '--quiet'] + list(libs),
+    fail_okay=True
+))
+
+# Remove redundant dependencies
+needed = set(deps)
+for pkg in deps:
+    if pkg not in needed:
+        continue # this subtree has already been pruned
+    redundant = subprocess_get_lines(
+        ['pactree', '--unique', pkg]
+    )[1:] # first line is pkg itself
+    needed.difference_update(redundant)
+
+print(' '.join(sorted(needed)))