From 18f3327d9a99163a658697465eb00c31f86535eb Mon Sep 17 00:00:00 2001 From: "Miss Islington (bot)" <31488909+miss-islington@users.noreply.github.com> Date: Thu, 22 Nov 2018 06:17:34 -0800 Subject: [PATCH] bpo-24658: os.read() reuses _PY_READ_MAX (GH-10657) os_read_impl() now also truncates the size to _PY_READ_MAX on macOS, to avoid to allocate a larger buffer even if _Py_read() is limited to _PY_READ_MAX bytes (ex: INT_MAX on macOS). (cherry picked from commit 9a0d7a7648547ffb77144bf2480155f6d7940dea) Co-authored-by: Victor Stinner --- Modules/posixmodule.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c index 8ff487d8cc1f..dbd534cab06a 100644 --- a/Modules/posixmodule.c +++ b/Modules/posixmodule.c @@ -8021,11 +8021,7 @@ os_read_impl(PyObject *module, int fd, Py_ssize_t length) return posix_error(); } -#ifdef MS_WINDOWS - /* On Windows, the count parameter of read() is an int */ - if (length > INT_MAX) - length = INT_MAX; -#endif + length = Py_MIN(length, _PY_READ_MAX); buffer = PyBytes_FromStringAndSize((char *)NULL, length); if (buffer == NULL) -- 2.47.3