1 files changed, 86 insertions, 0 deletions
diff --git a/third_party/python/taskcluster_taskgraph/taskgraph/util/archive.py b/third_party/python/taskcluster_taskgraph/taskgraph/util/archive.py
new file mode 100644
index 0000000000..ee59ba4548
--- /dev/null
+++ b/third_party/python/taskcluster_taskgraph/taskgraph/util/archive.py
@@ -0,0 +1,86 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+
+import gzip
+import os
+import stat
+import tarfile
+
+# 2016-01-01T00:00:00+0000
+DEFAULT_MTIME = 1451606400
+
+
+def create_tar_from_files(fp, files):
+    """Create a tar file deterministically.
+
+    Receives a dict mapping names of files in the archive to local filesystem
+    paths or ``mozpack.files.BaseFile`` instances.
+
+    The files will be archived and written to the passed file handle opened
+    for writing.
+
+    Only regular files can be written.
+
+    FUTURE accept a filename argument (or create APIs to write files)
+    """
+    with tarfile.open(name="", mode="w", fileobj=fp, dereference=True) as tf:
+        for archive_path, f in sorted(files.items()):
+            if isinstance(f, str):
+                mode = os.stat(f).st_mode
+                f = open(f, "rb")
+            else:
+                mode = 0o0644
+
+            ti = tarfile.TarInfo(archive_path)
+            ti.mode = mode
+            ti.type = tarfile.REGTYPE
+
+            if not ti.isreg():
+                raise ValueError("not a regular file: %s" % f)
+
+            # Disallow setuid and setgid bits. This is an arbitrary restriction.
+            # However, since we set uid/gid to root:root, setuid and setgid
+            # would be a glaring security hole if the archive were
+            # uncompressed as root.
+            if ti.mode & (stat.S_ISUID | stat.S_ISGID):
+                raise ValueError("cannot add file with setuid or setgid set: " "%s" % f)
+
+            # Set uid, gid, username, and group as deterministic values.
+            ti.uid = 0
+            ti.gid = 0
+            ti.uname = ""
+            ti.gname = ""
+
+            # Set mtime to a constant value.
+            ti.mtime = DEFAULT_MTIME
+
+            f.seek(0, 2)
+            ti.size = f.tell()
+            f.seek(0, 0)
+            # tarfile wants to pass a size argument to read(). So just
+            # wrap/buffer in a proper file object interface.
+            tf.addfile(ti, f)
+
+
+def create_tar_gz_from_files(fp, files, filename=None, compresslevel=9):
+    """Create a tar.gz file deterministically from files.
+
+    This is a glorified wrapper around ``create_tar_from_files`` that
+    adds gzip compression.
+
+    The passed file handle should be opened for writing in binary mode.
+    When the function returns, all data has been written to the handle.
+    """
+    # Offset 3-7 in the gzip header contains an mtime. Pin it to a known
+    # value so output is deterministic.
+    gf = gzip.GzipFile(
+        filename=filename or "",
+        mode="wb",
+        fileobj=fp,
+        compresslevel=compresslevel,
+        mtime=DEFAULT_MTIME,
+    )
+    with gf:
+        create_tar_from_files(gf, files)