New submission from Serhiy Storchaka <storchaka+cpyt...@gmail.com>:
Function getenvironment() in Modules/_winapi.c is used for converting the environment mapping to the wchar_t string for passing to CreateProcessW(). It performs the following steps: * Allocate a Py_UCS4 buffer and copy all keys and values, converting them to Py_UCS4. * Create a PyUnicode object from the Py_UCS4 buffer. * Create a wchar_t buffer from the PyUnicode object (unless it has the UCS2 kind). The proposed PR makes it performing a single steps: * Allocate a wchar_t buffer and copy all keys and values, converting them to wchar_t. This needs less memory allocations and smaller memory consumption. In most cases this needs also less and faster memory scans and copies. In addition, the PR replaces PySequence_Fast C API with faster PyList C API. In the past PyMapping_Keys() and PyMapping_Values() could return a tuple in unlikely case, but now they always return a list (see issue 28280). The current code uses the legacy Unicode C API, while the new code uses the newer (added in 3.3) wchar_t based Unicode C API, so something similar to this change should be made sooner or later. ---------- components: Extension Modules messages: 338527 nosy: lemburg, serhiy.storchaka priority: normal severity: normal status: open title: Refactor getenvironment() in _winapi.c versions: Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue36387> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
