| Edward Lemur | a44d67c | 2019-08-20 00:52:42 +0000 | [diff] [blame] | 1 | @echo off |
| 2 | :: Copyright 2017 The Chromium Authors. All rights reserved. |
| 3 | :: Use of this source code is governed by a BSD-style license that can be |
| 4 | :: found in the LICENSE file. |
| 5 | |
| 6 | setlocal |
| 7 | set PYTHON_BAT_RUNNER=1 |
| 8 | |
| 9 | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
| 10 | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
| 11 | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
| 12 | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
| 13 | :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: |
| 14 | |
| 15 | :: This file is automatically generated by "bootstrap\win\win_tools.py", and |
| 16 | :: should not be modified. |
| 17 | :: |
| 18 | :: The previous "::" block acts as a nop-sled. Each time a batch file executes |
| 19 | :: a command, it reloads itself and seeks to its previous execution offset to |
| 20 | :: begin execution. Updating this batch file is, therefore, risky, since any |
| 21 | :: running Python instance that is using the old batch file will reload the new |
| 22 | :: batch file once the Python command terminates and resume at some unknown |
| 23 | :: offset. |
| 24 | :: |
| 25 | :: With the sled in place, a previous instance will resume mid-label. We are |
| 26 | :: assuming that the offset of the Python invocation is greater than the |
| 27 | :: PYTHON_BAT_RUNNER set command, which is the case since the old instance has |
| 28 | :: a large PATH set block before the Python execution. Old instances will hit |
| 29 | :: the next block of code without PYTHON_BAT_RUNNER set. New instances will have |
| 30 | :: it set. |
| 31 | :: |
| 32 | :: We remedy this in the future by having the batch file load its core paths |
| 33 | :: from an external file with for/set, removing the need to modify "python.bat" |
| 34 | :: during upgrade. |
| 35 | :: |
| 36 | :: After all of the old batch files are believed to be replaced, we can remove |
| 37 | :: the PYTHON_BAT_RUNNER block and the sled. For this update, old instances |
| 38 | :: will resume past the end of the file and terminate. |
| 39 | |
| 40 | if not "%PYTHON_BAT_RUNNER%" == "1" goto :END |
| 41 | |
| 42 | for /f %%i in (%~dp0python3_bin_reldir.txt) do set PYTHON3_BIN_RELDIR=%%i |
| 43 | set PATH=%~dp0%PYTHON3_BIN_RELDIR%;%~dp0%PYTHON3_BIN_RELDIR%\Scripts;%PATH% |
| 44 | "%~dp0%PYTHON3_BIN_RELDIR%\python3.exe" %* |
| 45 | |
| 46 | :END |