bpo-34783: Fix Py_Main() (GH-9526)
Fix a crash with musl libc (on Alpine Linux) when the script filename
specified on the command line doesn't exist. pymain_open_filename()
now gets the current core configuration from the interpreter state.
Modify the code to make it closer to the master branch:
* Rename _Py_CommandLineDetails to _PyCmdline
* Remove _PyMain.config: replaced with a local variable
'local_config' in pymain_init()
* Reorganize pymain_main(): move code using the "local config"
into pymain_init()
* As soon as possible, switch from the local config to the core
configuration attached to the interpreter.
diff --git a/Modules/main.c b/Modules/main.c
index 0f7498d..7771d27 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -459,7 +459,7 @@
int legacy_windows_stdio; /* Py_LegacyWindowsStdioFlag,
PYTHONLEGACYWINDOWSSTDIO */
#endif
-} _Py_CommandLineDetails;
+} _PyCmdline;
/* Structure used by Py_Main() to pass data to subfunctions */
typedef struct {
@@ -481,14 +481,10 @@
wchar_t *command; /* -c argument */
wchar_t *module; /* -m argument */
- _PyCoreConfig config;
-
PyObject *main_importer_path;
} _PyMain;
-#define _PyMain_INIT \
- {.config = _PyCoreConfig_INIT, \
- .err = _Py_INIT_OK()}
+#define _PyMain_INIT {.err = _Py_INIT_OK()}
/* Note: _PyMain_INIT sets other fields to 0/NULL */
@@ -522,7 +518,8 @@
static int
-pymain_init_cmdline_argv(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_init_cmdline_argv(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
assert(cmdline->argv == NULL);
@@ -561,8 +558,8 @@
else {
program = L"";
}
- pymain->config.program = pymain_wstrdup(pymain, program);
- if (pymain->config.program == NULL) {
+ config->program = pymain_wstrdup(pymain, program);
+ if (config->program == NULL) {
return -1;
}
@@ -571,7 +568,7 @@
static void
-pymain_clear_cmdline(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_clear_cmdline(_PyMain *pymain, _PyCmdline *cmdline)
{
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
@@ -609,14 +606,14 @@
}
static void
-pymain_clear_config(_PyMain *pymain)
+pymain_clear_config(_PyCoreConfig *config)
{
/* Clear core config with the memory allocator
used by pymain_read_conf() */
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
- _PyCoreConfig_Clear(&pymain->config);
+ _PyCoreConfig_Clear(config);
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
}
@@ -653,8 +650,6 @@
Py_Initialize()-Py_Finalize() can be called multiple times. */
_PyPathConfig_Clear(&_Py_path_config);
- pymain_clear_config(pymain);
-
/* Force the allocator used by pymain_read_conf() */
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
@@ -740,10 +735,9 @@
Return 1 if parsing failed.
Set pymain->err and return -1 on other errors. */
static int
-pymain_parse_cmdline_impl(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_parse_cmdline_impl(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
- _PyCoreConfig *config = &pymain->config;
-
_PyOS_ResetGetOpt();
do {
int longindex = -1;
@@ -985,7 +979,7 @@
static _PyInitError
-config_init_warnoptions(_PyCoreConfig *config, _Py_CommandLineDetails *cmdline)
+config_init_warnoptions(_PyCoreConfig *config, _PyCmdline *cmdline)
{
_PyInitError err;
@@ -1056,7 +1050,7 @@
Return 0 on success.
Set pymain->err and return -1 on error. */
static _PyInitError
-cmdline_init_env_warnoptions(_Py_CommandLineDetails *cmdline)
+cmdline_init_env_warnoptions(_PyCmdline *cmdline)
{
if (Py_IgnoreEnvironmentFlag) {
return _Py_INIT_OK();
@@ -1252,7 +1246,8 @@
static int
-pymain_init_core_argv(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_init_core_argv(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
/* Copy argv to be able to modify it (to force -c/-m) */
int argc = pymain->argc - _PyOS_optind;
@@ -1295,8 +1290,8 @@
argv[0] = arg0;
}
- pymain->config.argc = argc;
- pymain->config.argv = argv;
+ config->argc = argc;
+ config->argv = argv;
return 0;
}
@@ -1324,7 +1319,7 @@
static int
-pymain_compute_path0(_PyMain *pymain, PyObject **path0)
+pymain_compute_path0(_PyMain *pymain, _PyCoreConfig *config, PyObject **path0)
{
if (pymain->main_importer_path != NULL) {
/* Let pymain_run_main_from_importer() adjust sys.path[0] later */
@@ -1337,8 +1332,7 @@
return 0;
}
- *path0 = _PyPathConfig_ComputeArgv0(pymain->config.argc,
- pymain->config.argv);
+ *path0 = _PyPathConfig_ComputeArgv0(config->argc, config->argv);
if (*path0 == NULL) {
pymain->err = _Py_INIT_NO_MEMORY();
return -1;
@@ -1384,7 +1378,7 @@
/* Get Py_xxx global configuration variables */
static void
-cmdline_get_global_config(_Py_CommandLineDetails *cmdline)
+cmdline_get_global_config(_PyCmdline *cmdline)
{
cmdline->bytes_warning = Py_BytesWarningFlag;
cmdline->debug = Py_DebugFlag;
@@ -1420,7 +1414,7 @@
/* Set Py_xxx global configuration variables */
static void
-cmdline_set_global_config(_Py_CommandLineDetails *cmdline)
+cmdline_set_global_config(_PyCmdline *cmdline)
{
Py_BytesWarningFlag = cmdline->bytes_warning;
Py_DebugFlag = cmdline->debug;
@@ -1468,6 +1462,7 @@
static FILE*
pymain_open_filename(_PyMain *pymain)
{
+ const _PyCoreConfig *config = &_PyGILState_GetInterpreterStateUnsafe()->core_config;
FILE* fp;
fp = _Py_wfopen(pymain->filename, L"r");
@@ -1481,7 +1476,7 @@
else
cfilename = "<unprintable file name>";
fprintf(stderr, "%ls: can't open file '%s': [Errno %d] %s\n",
- pymain->config.program, cfilename, err, strerror(err));
+ config->program, cfilename, err, strerror(err));
PyMem_RawFree(cfilename_buffer);
pymain->status = 2;
return NULL;
@@ -1504,7 +1499,7 @@
S_ISDIR(sb.st_mode)) {
fprintf(stderr,
"%ls: '%ls' is a directory, cannot continue\n",
- pymain->config.program, pymain->filename);
+ config->program, pymain->filename);
fclose(fp);
pymain->status = 1;
return NULL;
@@ -1571,14 +1566,15 @@
Return 0 on success.
Set pymain->err and return -1 on failure. */
static int
-pymain_parse_cmdline(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_parse_cmdline(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
- int res = pymain_parse_cmdline_impl(pymain, cmdline);
+ int res = pymain_parse_cmdline_impl(pymain, config, cmdline);
if (res < 0) {
return -1;
}
if (res) {
- pymain_usage(1, pymain->config.program);
+ pymain_usage(1, config->program);
pymain->status = 2;
return 1;
}
@@ -1716,7 +1712,7 @@
static void
-cmdline_get_env_flags(_Py_CommandLineDetails *cmdline)
+cmdline_get_env_flags(_PyCmdline *cmdline)
{
get_env_flag(&cmdline->debug, "PYTHONDEBUG");
get_env_flag(&cmdline->verbosity, "PYTHONVERBOSE");
@@ -1738,7 +1734,7 @@
void
_Py_Initialize_ReadEnvVarsNoAlloc(void)
{
- _Py_CommandLineDetails cmdline;
+ _PyCmdline cmdline;
memset(&cmdline, 0, sizeof(cmdline));
cmdline_get_global_config(&cmdline);
@@ -1926,17 +1922,17 @@
Return 1 if Python is done and must exit.
Set pymain->err and return -1 on error. */
static int
-pymain_read_conf_impl(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_read_conf_impl(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
_PyInitError err;
- int res = pymain_parse_cmdline(pymain, cmdline);
+ int res = pymain_parse_cmdline(pymain, config, cmdline);
if (res != 0) {
return res;
}
/* Set Py_IgnoreEnvironmentFlag for Py_GETENV() */
- _PyCoreConfig *config = &pymain->config;
Py_IgnoreEnvironmentFlag = config->ignore_environment || cmdline->isolated;
/* Get environment variables */
@@ -1956,7 +1952,7 @@
}
#endif
- if (pymain_init_core_argv(pymain, cmdline) < 0) {
+ if (pymain_init_core_argv(pymain, config, cmdline) < 0) {
return -1;
}
@@ -1985,10 +1981,9 @@
/* Read the configuration, but initialize also the LC_CTYPE locale:
enable UTF-8 mode (PEP 540) and/or coerce the C locale (PEP 538) */
static int
-pymain_read_conf(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_read_conf(_PyMain *pymain, _PyCoreConfig *config, _PyCmdline *cmdline)
{
int init_utf8_mode = Py_UTF8Mode;
- _PyCoreConfig *config = &pymain->config;
_PyCoreConfig save_config = _PyCoreConfig_INIT;
int res = -1;
@@ -2026,11 +2021,11 @@
functions depend on Py_UTF8Mode. */
Py_UTF8Mode = config->utf8_mode;
- if (pymain_init_cmdline_argv(pymain, cmdline) < 0) {
+ if (pymain_init_cmdline_argv(pymain, config, cmdline) < 0) {
goto done;
}
- int conf_res = pymain_read_conf_impl(pymain, cmdline);
+ int conf_res = pymain_read_conf_impl(pymain, config, cmdline);
if (conf_res != 0) {
res = conf_res;
goto done;
@@ -2587,7 +2582,7 @@
static int
-pymain_init_sys_path(_PyMain *pymain)
+pymain_init_sys_path(_PyMain *pymain, _PyCoreConfig *config)
{
if (pymain->filename != NULL) {
/* If filename is a package (ex: directory or ZIP file) which contains
@@ -2598,12 +2593,10 @@
}
PyObject *path0;
- if (pymain_compute_path0(pymain, &path0) < 0) {
+ if (pymain_compute_path0(pymain, config, &path0) < 0) {
return -1;
}
- pymain_clear_config(pymain);
-
if (path0 != NULL) {
if (pymain_update_sys_path(pymain, path0) < 0) {
Py_DECREF(path0);
@@ -2637,32 +2630,16 @@
}
-static void
-pymain_init(_PyMain *pymain)
-{
- /* 754 requires that FP exceptions run in "no stop" mode by default,
- * and until C vendors implement C99's ways to control FP exceptions,
- * Python requires non-stop mode. Alas, some platforms enable FP
- * exceptions by default. Here we disable them.
- */
-#ifdef __FreeBSD__
- fedisableexcept(FE_OVERFLOW);
-#endif
-
- pymain->config._disable_importlib = 0;
- pymain->config.install_signal_handlers = 1;
-}
-
-
static int
-pymain_cmdline_impl(_PyMain *pymain, _Py_CommandLineDetails *cmdline)
+pymain_cmdline_impl(_PyMain *pymain, _PyCoreConfig *config,
+ _PyCmdline *cmdline)
{
pymain->err = _PyRuntime_Initialize();
if (_Py_INIT_FAILED(pymain->err)) {
return -1;
}
- int res = pymain_read_conf(pymain, cmdline);
+ int res = pymain_read_conf(pymain, config, cmdline);
if (res < 0) {
return -1;
}
@@ -2672,7 +2649,7 @@
}
if (cmdline->print_help) {
- pymain_usage(0, pymain->config.program);
+ pymain_usage(0, config->program);
return 1;
}
@@ -2690,7 +2667,7 @@
}
orig_argc = pymain->argc;
- _PyInitError err = config_init_warnoptions(&pymain->config, cmdline);
+ _PyInitError err = config_init_warnoptions(config, cmdline);
if (_Py_INIT_FAILED(err)) {
pymain->err = err;
return -1;
@@ -2708,10 +2685,10 @@
* Environment variables
* Py_xxx global configuration variables
- _Py_CommandLineDetails is a temporary structure used to prioritize these
+ _PyCmdline is a temporary structure used to prioritize these
variables. */
static int
-pymain_cmdline(_PyMain *pymain)
+pymain_cmdline(_PyMain *pymain, _PyCoreConfig *config)
{
/* Force default allocator, since pymain_free() and pymain_clear_config()
must use the same allocator than this function. */
@@ -2722,16 +2699,15 @@
PyMem_GetAllocator(PYMEM_DOMAIN_RAW, &default_alloc);
#endif
- _Py_CommandLineDetails cmdline;
+ _PyCmdline cmdline;
memset(&cmdline, 0, sizeof(cmdline));
cmdline_get_global_config(&cmdline);
- _PyCoreConfig_GetGlobalConfig(&pymain->config);
- int res = pymain_cmdline_impl(pymain, &cmdline);
+ int res = pymain_cmdline_impl(pymain, config, &cmdline);
cmdline_set_global_config(&cmdline);
- _PyCoreConfig_SetGlobalConfig(&pymain->config);
+ _PyCoreConfig_SetGlobalConfig(config);
if (Py_IsolatedFlag) {
Py_IgnoreEnvironmentFlag = 1;
Py_NoUserSiteDirectory = 1;
@@ -2751,33 +2727,62 @@
static int
-pymain_main(_PyMain *pymain)
+pymain_init(_PyMain *pymain)
{
- pymain_init(pymain);
+ _PyCoreConfig local_config = _PyCoreConfig_INIT;
+ _PyCoreConfig *config = &local_config;
- int res = pymain_cmdline(pymain);
+ /* 754 requires that FP exceptions run in "no stop" mode by default,
+ * and until C vendors implement C99's ways to control FP exceptions,
+ * Python requires non-stop mode. Alas, some platforms enable FP
+ * exceptions by default. Here we disable them.
+ */
+#ifdef __FreeBSD__
+ fedisableexcept(FE_OVERFLOW);
+#endif
+
+ config->_disable_importlib = 0;
+ config->install_signal_handlers = 1;
+ _PyCoreConfig_GetGlobalConfig(config);
+
+ int res = pymain_cmdline(pymain, config);
if (res < 0) {
_Py_FatalInitError(pymain->err);
}
if (res == 1) {
- goto done;
+ pymain_clear_config(&local_config);
+ return res;
}
pymain_init_stdio(pymain);
PyInterpreterState *interp;
- pymain->err = _Py_InitializeCore(&interp, &pymain->config);
+ pymain->err = _Py_InitializeCore(&interp, config);
if (_Py_INIT_FAILED(pymain->err)) {
_Py_FatalInitError(pymain->err);
}
+ pymain_clear_config(&local_config);
+ config = &interp->core_config;
+
if (pymain_init_python_main(pymain, interp) < 0) {
_Py_FatalInitError(pymain->err);
}
- if (pymain_init_sys_path(pymain) < 0) {
+ if (pymain_init_sys_path(pymain, config) < 0) {
_Py_FatalInitError(pymain->err);
}
+ return 0;
+}
+
+
+static int
+pymain_main(_PyMain *pymain)
+{
+ int res = pymain_init(pymain);
+ if (res == 1) {
+ goto done;
+ }
pymain_run_python(pymain);