diff --git a/Doc/using/windows.rst b/Doc/using/windows.rst index 2db73c8c5b9c2c..a289435a2f51db 100644 --- a/Doc/using/windows.rst +++ b/Doc/using/windows.rst @@ -868,6 +868,11 @@ The ``/usr/bin/env`` form of shebang line has one further special property. Before looking for installed Python interpreters, this form will search the executable :envvar:`PATH` for a Python executable. This corresponds to the behaviour of the Unix ``env`` program, which performs a :envvar:`PATH` search. +If an executable matching the first argument after the ``env`` command cannot +be found, it will be handled as described below. Additionally, the environment +variable :envvar:`PYLAUNCHER_NO_SEARCH_PATH` may be set (to any value) to skip +this additional search. + Arguments in shebang lines -------------------------- diff --git a/Lib/test/test_launcher.py b/Lib/test/test_launcher.py index c8ea4f62170eac..b523b7cb48db33 100644 --- a/Lib/test/test_launcher.py +++ b/Lib/test/test_launcher.py @@ -194,9 +194,10 @@ def run_py(self, args, env=None, allow_fail=False, expect_returncode=0, argv=Non ignore = {"VIRTUAL_ENV", "PY_PYTHON", "PY_PYTHON2", "PY_PYTHON3"} env = { **{k.upper(): v for k, v in os.environ.items() if k.upper() not in ignore}, - **{k.upper(): v for k, v in (env or {}).items()}, + "PYLAUNCHER_NO_SEARCH_PATH": "1", "PYLAUNCHER_DEBUG": "1", "PYLAUNCHER_DRYRUN": "1", + **{k.upper(): v for k, v in (env or {}).items()}, } if not argv: argv = [self.py_exe, *args] @@ -551,6 +552,20 @@ def test_py_shebang_short_argv0(self): self.assertEqual("3.100", data["SearchInfo.tag"]) self.assertEqual(f'X.Y.exe -prearg "{script}" -postarg', data["stdout"].strip()) + def test_search_path(self): + stem = Path(sys.executable).stem + with self.py_ini(TEST_PY_COMMANDS): + with self.script(f"#! /usr/bin/env {stem} -prearg") as script: + data = self.run_py([script, "-postarg"], env={"PYLAUNCHER_NO_SEARCH_PATH": ""}) + self.assertEqual(f"{sys.executable} -prearg {script} -postarg", data["stdout"].strip()) + + def test_recursive_search_path(self): + with self.py_ini(TEST_PY_COMMANDS): + with self.script("#! /usr/bin/env py") as script: + data = self.run_py([script], env={"PYLAUNCHER_NO_SEARCH_PATH": ""}) + # The recursive search is ignored and we get normal "py" behavior + self.assertEqual(f"X.Y.exe {script}", data["stdout"].strip()) + def test_install(self): data = self.run_py(["-V:3.10"], env={"PYLAUNCHER_ALWAYS_INSTALL": "1"}, expect_returncode=111) cmd = data["stdout"].strip() diff --git a/Misc/NEWS.d/next/Windows/2022-08-03-00-49-46.gh-issue-94399.KvxHc0.rst b/Misc/NEWS.d/next/Windows/2022-08-03-00-49-46.gh-issue-94399.KvxHc0.rst new file mode 100644 index 00000000000000..a49e99ca266526 --- /dev/null +++ b/Misc/NEWS.d/next/Windows/2022-08-03-00-49-46.gh-issue-94399.KvxHc0.rst @@ -0,0 +1,3 @@ +Restores the behaviour of :ref:`launcher` for ``/usr/bin/env`` shebang +lines, which will now search :envvar:`PATH` for an executable matching the +given command. If none is found, the usual search process is used. diff --git a/PC/launcher2.c b/PC/launcher2.c index 033218ee2f408e..6006fb332cd617 100644 --- a/PC/launcher2.c +++ b/PC/launcher2.c @@ -36,6 +36,7 @@ #define RC_DUPLICATE_ITEM 110 #define RC_INSTALLING 111 #define RC_NO_PYTHON_AT_ALL 112 +#define RC_NO_SHEBANG 113 static FILE * log_fp = NULL; @@ -750,6 +751,78 @@ _shebangStartsWith(const wchar_t *buffer, int bufferLength, const wchar_t *prefi } +int +searchPath(SearchInfo *search, const wchar_t *shebang, int shebangLength) +{ + if (isEnvVarSet(L"PYLAUNCHER_NO_SEARCH_PATH")) { + return RC_NO_SHEBANG; + } + + wchar_t *command; + if (!_shebangStartsWith(shebang, shebangLength, L"/usr/bin/env ", &command)) { + return RC_NO_SHEBANG; + } + + wchar_t filename[MAXLEN]; + int lastDot = 0; + int commandLength = 0; + while (commandLength < MAXLEN && command[commandLength] && !isspace(command[commandLength])) { + if (command[commandLength] == L'.') { + lastDot = commandLength; + } + filename[commandLength] = command[commandLength]; + commandLength += 1; + } + + if (!commandLength || commandLength == MAXLEN) { + return RC_BAD_VIRTUAL_PATH; + } + + filename[commandLength] = L'\0'; + + const wchar_t *ext = L".exe"; + // If the command already has an extension, we do not want to add it again + if (!lastDot || _comparePath(&filename[lastDot], -1, ext, -1)) { + if (wcscat_s(filename, MAXLEN, L".exe")) { + return RC_BAD_VIRTUAL_PATH; + } + } + + wchar_t buffer[MAXLEN]; + SetSearchPathMode(BASE_SEARCH_PATH_ENABLE_SAFE_SEARCHMODE); + int n = SearchPathW(NULL, filename, NULL, MAXLEN, buffer, NULL); + if (!n) { + if (GetLastError() == ERROR_FILE_NOT_FOUND) { + // If we didn't find it on PATH, let normal handling take over + return RC_NO_SHEBANG; + } + // Other errors should cause us to break + winerror(0, L"Failed to find %s on PATH\n", filename); + return RC_BAD_VIRTUAL_PATH; + } + + // Check that we aren't going to call ourselves again + // If we are, pretend there was no shebang and let normal handling take over + if (GetModuleFileNameW(NULL, filename, MAXLEN) && + 0 == _comparePath(filename, -1, buffer, -1)) { + debug(L"# ignoring recursive shebang command\n"); + return RC_NO_SHEBANG; + } + + wchar_t *buf = allocSearchInfoBuffer(search, n + 1); + if (!buf || wcscpy_s(buf, n + 1, buffer)) { + return RC_NO_MEMORY; + } + + search->executablePath = buf; + search->executableArgs = &command[commandLength]; + search->executableArgsLength = shebangLength - commandLength; + debug(L"# Found %s on PATH\n", buf); + + return 0; +} + + int _readIni(const wchar_t *section, const wchar_t *settingName, wchar_t *buffer, int bufferLength) { @@ -885,6 +958,12 @@ checkShebang(SearchInfo *search) } debug(L"Shebang: %s\n", shebang); + // Handle shebangs that we should search PATH for + exitCode = searchPath(search, shebang, shebangLength); + if (exitCode != RC_NO_SHEBANG) { + return exitCode; + } + // Handle some known, case-sensitive shebang templates const wchar_t *command; int commandLength; @@ -895,6 +974,7 @@ checkShebang(SearchInfo *search) L"", NULL }; + for (const wchar_t **tmpl = shebangTemplates; *tmpl; ++tmpl) { if (_shebangStartsWith(shebang, shebangLength, *tmpl, &command)) { commandLength = 0;