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-rw-r--r--game/python-extra/urllib3/util/wait.py153
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diff --git a/game/python-extra/urllib3/util/wait.py b/game/python-extra/urllib3/util/wait.py
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+import errno
+from functools import partial
+import select
+import sys
+
+try:
+ from time import monotonic
+except ImportError:
+ from time import time as monotonic
+
+__all__ = ["NoWayToWaitForSocketError", "wait_for_read", "wait_for_write"]
+
+
+class NoWayToWaitForSocketError(Exception):
+ pass
+
+
+# How should we wait on sockets?
+#
+# There are two types of APIs you can use for waiting on sockets: the fancy
+# modern stateful APIs like epoll/kqueue, and the older stateless APIs like
+# select/poll. The stateful APIs are more efficient when you have a lots of
+# sockets to keep track of, because you can set them up once and then use them
+# lots of times. But we only ever want to wait on a single socket at a time
+# and don't want to keep track of state, so the stateless APIs are actually
+# more efficient. So we want to use select() or poll().
+#
+# Now, how do we choose between select() and poll()? On traditional Unixes,
+# select() has a strange calling convention that makes it slow, or fail
+# altogether, for high-numbered file descriptors. The point of poll() is to fix
+# that, so on Unixes, we prefer poll().
+#
+# On Windows, there is no poll() (or at least Python doesn't provide a wrapper
+# for it), but that's OK, because on Windows, select() doesn't have this
+# strange calling convention; plain select() works fine.
+#
+# So: on Windows we use select(), and everywhere else we use poll(). We also
+# fall back to select() in case poll() is somehow broken or missing.
+
+if sys.version_info >= (3, 5):
+ # Modern Python, that retries syscalls by default
+ def _retry_on_intr(fn, timeout):
+ return fn(timeout)
+
+
+else:
+ # Old and broken Pythons.
+ def _retry_on_intr(fn, timeout):
+ if timeout is None:
+ deadline = float("inf")
+ else:
+ deadline = monotonic() + timeout
+
+ while True:
+ try:
+ return fn(timeout)
+ # OSError for 3 <= pyver < 3.5, select.error for pyver <= 2.7
+ except (OSError, select.error) as e:
+ # 'e.args[0]' incantation works for both OSError and select.error
+ if e.args[0] != errno.EINTR:
+ raise
+ else:
+ timeout = deadline - monotonic()
+ if timeout < 0:
+ timeout = 0
+ if timeout == float("inf"):
+ timeout = None
+ continue
+
+
+def select_wait_for_socket(sock, read=False, write=False, timeout=None):
+ if not read and not write:
+ raise RuntimeError("must specify at least one of read=True, write=True")
+ rcheck = []
+ wcheck = []
+ if read:
+ rcheck.append(sock)
+ if write:
+ wcheck.append(sock)
+ # When doing a non-blocking connect, most systems signal success by
+ # marking the socket writable. Windows, though, signals success by marked
+ # it as "exceptional". We paper over the difference by checking the write
+ # sockets for both conditions. (The stdlib selectors module does the same
+ # thing.)
+ fn = partial(select.select, rcheck, wcheck, wcheck)
+ rready, wready, xready = _retry_on_intr(fn, timeout)
+ return bool(rready or wready or xready)
+
+
+def poll_wait_for_socket(sock, read=False, write=False, timeout=None):
+ if not read and not write:
+ raise RuntimeError("must specify at least one of read=True, write=True")
+ mask = 0
+ if read:
+ mask |= select.POLLIN
+ if write:
+ mask |= select.POLLOUT
+ poll_obj = select.poll()
+ poll_obj.register(sock, mask)
+
+ # For some reason, poll() takes timeout in milliseconds
+ def do_poll(t):
+ if t is not None:
+ t *= 1000
+ return poll_obj.poll(t)
+
+ return bool(_retry_on_intr(do_poll, timeout))
+
+
+def null_wait_for_socket(*args, **kwargs):
+ raise NoWayToWaitForSocketError("no select-equivalent available")
+
+
+def _have_working_poll():
+ # Apparently some systems have a select.poll that fails as soon as you try
+ # to use it, either due to strange configuration or broken monkeypatching
+ # from libraries like eventlet/greenlet.
+ try:
+ poll_obj = select.poll()
+ _retry_on_intr(poll_obj.poll, 0)
+ except (AttributeError, OSError):
+ return False
+ else:
+ return True
+
+
+def wait_for_socket(*args, **kwargs):
+ # We delay choosing which implementation to use until the first time we're
+ # called. We could do it at import time, but then we might make the wrong
+ # decision if someone goes wild with monkeypatching select.poll after
+ # we're imported.
+ global wait_for_socket
+ if _have_working_poll():
+ wait_for_socket = poll_wait_for_socket
+ elif hasattr(select, "select"):
+ wait_for_socket = select_wait_for_socket
+ else: # Platform-specific: Appengine.
+ wait_for_socket = null_wait_for_socket
+ return wait_for_socket(*args, **kwargs)
+
+
+def wait_for_read(sock, timeout=None):
+ """ Waits for reading to be available on a given socket.
+ Returns True if the socket is readable, or False if the timeout expired.
+ """
+ return wait_for_socket(sock, read=True, timeout=timeout)
+
+
+def wait_for_write(sock, timeout=None):
+ """ Waits for writing to be available on a given socket.
+ Returns True if the socket is readable, or False if the timeout expired.
+ """
+ return wait_for_socket(sock, write=True, timeout=timeout)