From 3beabe653d377089a734c1097ba8d0fbc54c3a9a Mon Sep 17 00:00:00 2001
From: Suzanne Soy <git@suzanne.soy>
Date: Sun, 21 Feb 2021 15:50:17 +0000
Subject: [PATCH] WIP

---
 hash-files.py | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100755 hash-files.py

diff --git a/hash-files.py b/hash-files.py
new file mode 100755
index 0000000..8fc719f
--- /dev/null
+++ b/hash-files.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+
+import os
+import sys
+import subprocess
+
+def hashFile(filename):
+  #print("hashFile " + filename)
+  return subprocess.check_output(['sha256sum', '--binary', '--zero', filename])[0:64]
+
+def hash1(bytes):
+  #print("hash1 " + bytes)
+  return subprocess.check_output(['sha256sum', '--binary', '--zero'], input=bytes)[0:64]
+
+def hashN(bytesList):
+  #print("hashN ")
+  #print(b''.join(bytesList))
+  return subprocess.check_output(['sha256sum', '--binary', '--zero'], input = b''.join(bytesList))[0:64]
+
+#
+# TODO: use this to get the hashes and names for all roots of the DAG (commits that are reachable only through one (or several) direct branch names, but not transitively as ancestors of other commits)
+#
+git_command='''
+  (
+    (
+      git log --format=%P --all HEAD FETCH_HEAD | tr ' ' \\n | grep -v '^$' | sort -u | sed -e 'p;p';
+      git rev-parse HEAD FETCH_HEAD --all | sort -u
+    ) | sort | uniq -u;
+    for ref in HEAD FETCH_HEAD; do echo "$(git rev-parse $ref) $ref"; done; git for-each-ref --format='%(objectname) %(refname)'
+  ) | sort | awk 'BEGIN { h="" } { if (length($0) == 40) { h=$0 } else { if (substr($0,1,40) == h) print $0 } }' | sort -k 2
+'''
+
+def hashGit(path):
+  return subprocess.check_output(['sh', '-c', git_command])
+
+sqlite3_command='''
+  (
+    sqlite3 file.db .dump | sort | sha256sum --binary --zero
+  )
+'''
+
+def hashSqlite3(path):
+  pass # TODO…
+
+def recur(x):
+  #print(x)
+  # initial list of paths
+  if isinstance(x, list):
+    return hashN([b'root\0'] + [recur(os.path.abspath(path)) + b'  ' + path.encode('utf-8') + b'\0' for path in sorted(x)])
+  # GIT repo
+  elif os.path.isdir(x) and os.path.exists(os.path.join(x, '.git')):
+    print("GIT DIR")
+    return hashN([b'git-versioned folder\0', hashGit(x)])
+  # directory
+  elif os.path.isdir(x):
+   return hashN([b'directory\0'] + [recur(entry) + b'  ' + entry.encode('utf-8') + b'\0' for entry in os.listdir(x)])
+  # Just a file
+  elif os.path.isfile(x):
+    return hashFile(x)
+  else:
+    sys.exit("unknown file type for %s" % f)
+
+print(recur(sys.argv[1:]).decode('utf-8'))