Add zstd.

3rdparty/zstd-1.5.0/tests/rateLimiter.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+
+# ################################################################
+# Copyright (c) Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under both the BSD-style license (found in the
+# LICENSE file in the root directory of this source tree) and the GPLv2 (found
+# in the COPYING file in the root directory of this source tree).
+# You may select, at your option, one of the above-listed licenses.
+# ##########################################################################
+
+# Rate limiter, replacement for pv
+# this rate limiter does not "catch up" after a blocking period
+# Limitations:
+# - only accepts limit speed in MB/s
+
+import sys
+import time
+
+MB = 1024 * 1024
+rate = float(sys.argv[1]) * MB
+start = time.time()
+total_read = 0
+
+# sys.stderr.close()  # remove error message, for Ctrl+C
+
+try:
+  buf = " "
+  while len(buf):
+    now = time.time()
+    to_read = max(int(rate * (now - start)), 1)
+    max_buf_size = 1 * MB
+    to_read = min(to_read, max_buf_size)
+    start = now
+
+    buf = sys.stdin.buffer.read(to_read)
+    sys.stdout.buffer.write(buf)
+
+except (KeyboardInterrupt, BrokenPipeError) as e:
+    pass