bpo-28441: Ensure `.exe` suffix in `sys.executable` on MinGW and Cygwin (GH-4348)
This is needed to even the run the test suite on buildbots for affected platforms; e.g.:
```
./python.exe ./Tools/scripts/run_tests.py -j 1 -u all -W --slowest --fail-env-changed --timeout=11700 -j2
/home/embray/src/python/test-worker/3.x.test-worker/build/python -u -W default -bb -E -W error::BytesWarning -m test -r -w -j 1 -u all -W --slowest --fail-env-changed --timeout=11700 -j2
Traceback (most recent call last):
File "./Tools/scripts/run_tests.py", line 56, in <module>
main(sys.argv[1:])
File "./Tools/scripts/run_tests.py", line 52, in main
os.execv(sys.executable, args)
PermissionError: [Errno 13] Permission denied
make: *** [Makefile:1073: buildbottest] Error 1
```
(cherry picked from commit 7a7693e9cb12e5571c76331db56a28eef9acb6e0)
Co-authored-by: E. M. Bray <erik.m.bray@gmail.com>diff --git a/Modules/getpath.c b/Modules/getpath.c
index e6a3e8e..bfb3331 100644
--- a/Modules/getpath.c
+++ b/Modules/getpath.c
@@ -296,6 +296,41 @@
}
+#if defined(__CYGWIN__) || defined(__MINGW32__)
+/* add_exe_suffix requires that progpath be allocated at least
+ MAXPATHLEN + 1 bytes.
+*/
+
+#ifndef EXE_SUFFIX
+#define EXE_SUFFIX L".exe"
+#endif
+
+static void
+add_exe_suffix(wchar_t *progpath)
+{
+ /* Check for already have an executable suffix */
+ size_t n = wcslen(progpath);
+ size_t s = wcslen(EXE_SUFFIX);
+ if (wcsncasecmp(EXE_SUFFIX, progpath+n-s, s) != 0) {
+ if (n + s > MAXPATHLEN) {
+ Py_FatalError("progpath overflow in getpath.c's add_exe_suffix()");
+ }
+ /* Save original path for revert */
+ wchar_t orig[MAXPATHLEN+1];
+ wcsncpy(orig, progpath, MAXPATHLEN);
+
+ wcsncpy(progpath+n, EXE_SUFFIX, s);
+ progpath[n+s] = '\0';
+
+ if (!isxfile(progpath)) {
+ /* Path that added suffix is invalid */
+ wcsncpy(progpath, orig, MAXPATHLEN);
+ }
+ }
+}
+#endif
+
+
/* search_for_prefix requires that argv0_path be no more than MAXPATHLEN
bytes long.
*/
@@ -605,6 +640,16 @@
if (program_full_path[0] != SEP && program_full_path[0] != '\0') {
absolutize(program_full_path);
}
+#if defined(__CYGWIN__) || defined(__MINGW32__)
+ /* For these platforms it is necessary to ensure that the .exe suffix
+ * is appended to the filename, otherwise there is potential for
+ * sys.executable to return the name of a directory under the same
+ * path (bpo-28441).
+ */
+ if (program_full_path[0] != '\0') {
+ add_exe_suffix(program_full_path);
+ }
+#endif
config->program_full_path = _PyMem_RawWcsdup(program_full_path);
if (config->program_full_path == NULL) {