Staging
v0.8.1
v0.8.1
main.c
/* Python interpreter main program */
#include "Python.h"
#include "pycore_coreconfig.h"
#include "pycore_pylifecycle.h"
#include "pycore_pymem.h"
#include "pycore_pystate.h"
#ifdef __FreeBSD__
# include <fenv.h> /* fedisableexcept() */
#endif
/* Includes for exit_sigint() */
#include <stdio.h> /* perror() */
#ifdef HAVE_SIGNAL_H
# include <signal.h> /* SIGINT */
#endif
#if defined(HAVE_GETPID) && defined(HAVE_UNISTD_H)
# include <unistd.h> /* getpid() */
#endif
#ifdef _MSC_VER
# include <crtdbg.h> /* STATUS_CONTROL_C_EXIT */
#endif
/* End of includes for exit_sigint() */
#define COPYRIGHT \
"Type \"help\", \"copyright\", \"credits\" or \"license\" " \
"for more information."
#ifdef __cplusplus
extern "C" {
#endif
/* --- PyMainInterpreter ------------------------------------------ */
void
_PyMainInterpreterConfig_Clear(_PyMainInterpreterConfig *config)
{
Py_CLEAR(config->argv);
Py_CLEAR(config->executable);
Py_CLEAR(config->prefix);
Py_CLEAR(config->base_prefix);
Py_CLEAR(config->exec_prefix);
Py_CLEAR(config->base_exec_prefix);
Py_CLEAR(config->warnoptions);
Py_CLEAR(config->xoptions);
Py_CLEAR(config->module_search_path);
Py_CLEAR(config->pycache_prefix);
}
static int
mainconfig_add_xoption(PyObject *opts, const wchar_t *s)
{
PyObject *name, *value;
const wchar_t *name_end = wcschr(s, L'=');
if (!name_end) {
name = PyUnicode_FromWideChar(s, -1);
value = Py_True;
Py_INCREF(value);
}
else {
name = PyUnicode_FromWideChar(s, name_end - s);
value = PyUnicode_FromWideChar(name_end + 1, -1);
}
if (name == NULL || value == NULL) {
goto error;
}
if (PyDict_SetItem(opts, name, value) < 0) {
goto error;
}
Py_DECREF(name);
Py_DECREF(value);
return 0;
error:
Py_XDECREF(name);
Py_XDECREF(value);
return -1;
}
static PyObject*
mainconfig_create_xoptions_dict(const _PyCoreConfig *config)
{
Py_ssize_t nxoption = config->xoptions.length;
wchar_t * const * xoptions = config->xoptions.items;
PyObject *dict = PyDict_New();
if (dict == NULL) {
return NULL;
}
for (Py_ssize_t i=0; i < nxoption; i++) {
const wchar_t *option = xoptions[i];
if (mainconfig_add_xoption(dict, option) < 0) {
Py_DECREF(dict);
return NULL;
}
}
return dict;
}
static PyObject*
mainconfig_copy_attr(PyObject *obj)
{
if (PyUnicode_Check(obj)) {
Py_INCREF(obj);
return obj;
}
else if (PyList_Check(obj)) {
return PyList_GetSlice(obj, 0, Py_SIZE(obj));
}
else if (PyDict_Check(obj)) {
/* The dict type is used for xoptions. Make the assumption that keys
and values are immutables */
return PyDict_Copy(obj);
}
else {
PyErr_Format(PyExc_TypeError,
"cannot copy config attribute of type %.200s",
Py_TYPE(obj)->tp_name);
return NULL;
}
}
int
_PyMainInterpreterConfig_Copy(_PyMainInterpreterConfig *config,
const _PyMainInterpreterConfig *config2)
{
_PyMainInterpreterConfig_Clear(config);
#define COPY_ATTR(ATTR) config->ATTR = config2->ATTR
#define COPY_OBJ_ATTR(ATTR) \
do { \
if (config2->ATTR != NULL) { \
config->ATTR = mainconfig_copy_attr(config2->ATTR); \
if (config->ATTR == NULL) { \
return -1; \
} \
} \
} while (0)
COPY_ATTR(install_signal_handlers);
COPY_OBJ_ATTR(argv);
COPY_OBJ_ATTR(executable);
COPY_OBJ_ATTR(prefix);
COPY_OBJ_ATTR(base_prefix);
COPY_OBJ_ATTR(exec_prefix);
COPY_OBJ_ATTR(base_exec_prefix);
COPY_OBJ_ATTR(warnoptions);
COPY_OBJ_ATTR(xoptions);
COPY_OBJ_ATTR(module_search_path);
COPY_OBJ_ATTR(pycache_prefix);
#undef COPY_ATTR
#undef COPY_OBJ_ATTR
return 0;
}
PyObject*
_PyMainInterpreterConfig_AsDict(const _PyMainInterpreterConfig *config)
{
PyObject *dict, *obj;
int res;
dict = PyDict_New();
if (dict == NULL) {
return NULL;
}
#define SET_ITEM_INT(ATTR) \
do { \
obj = PyLong_FromLong(config->ATTR); \
if (obj == NULL) { \
goto fail; \
} \
res = PyDict_SetItemString(dict, #ATTR, obj); \
Py_DECREF(obj); \
if (res < 0) { \
goto fail; \
} \
} while (0)
#define SET_ITEM_OBJ(ATTR) \
do { \
obj = config->ATTR; \
if (obj == NULL) { \
obj = Py_None; \
} \
res = PyDict_SetItemString(dict, #ATTR, obj); \
if (res < 0) { \
goto fail; \
} \
} while (0)
SET_ITEM_INT(install_signal_handlers);
SET_ITEM_OBJ(argv);
SET_ITEM_OBJ(executable);
SET_ITEM_OBJ(prefix);
SET_ITEM_OBJ(base_prefix);
SET_ITEM_OBJ(exec_prefix);
SET_ITEM_OBJ(base_exec_prefix);
SET_ITEM_OBJ(warnoptions);
SET_ITEM_OBJ(xoptions);
SET_ITEM_OBJ(module_search_path);
SET_ITEM_OBJ(pycache_prefix);
return dict;
fail:
Py_DECREF(dict);
return NULL;
#undef SET_ITEM_OBJ
}
_PyInitError
_PyMainInterpreterConfig_Read(_PyMainInterpreterConfig *main_config,
const _PyCoreConfig *config)
{
if (main_config->install_signal_handlers < 0) {
main_config->install_signal_handlers = config->install_signal_handlers;
}
if (main_config->xoptions == NULL) {
main_config->xoptions = mainconfig_create_xoptions_dict(config);
if (main_config->xoptions == NULL) {
return _Py_INIT_NO_MEMORY();
}
}
#define COPY_WSTR(ATTR) \
do { \
if (main_config->ATTR == NULL && config->ATTR != NULL) { \
main_config->ATTR = PyUnicode_FromWideChar(config->ATTR, -1); \
if (main_config->ATTR == NULL) { \
return _Py_INIT_NO_MEMORY(); \
} \
} \
} while (0)
#define COPY_WSTRLIST(ATTR, LIST) \
do { \
if (ATTR == NULL) { \
ATTR = _PyWstrList_AsList(LIST); \
if (ATTR == NULL) { \
return _Py_INIT_NO_MEMORY(); \
} \
} \
} while (0)
COPY_WSTRLIST(main_config->warnoptions, &config->warnoptions);
COPY_WSTRLIST(main_config->argv, &config->argv);
if (config->_install_importlib) {
COPY_WSTR(executable);
COPY_WSTR(prefix);
COPY_WSTR(base_prefix);
COPY_WSTR(exec_prefix);
COPY_WSTR(base_exec_prefix);
COPY_WSTRLIST(main_config->module_search_path,
&config->module_search_paths);
if (config->pycache_prefix != NULL) {
COPY_WSTR(pycache_prefix);
} else {
main_config->pycache_prefix = NULL;
}
}
return _Py_INIT_OK();
#undef COPY_WSTR
#undef COPY_WSTRLIST
}
/* --- pymain_init() ---------------------------------------------- */
static _PyInitError
pymain_init_preconfig(const _PyArgv *args)
{
_PyInitError err;
_PyPreConfig config = _PyPreConfig_INIT;
err = _PyPreConfig_ReadFromArgv(&config, args);
if (_Py_INIT_FAILED(err)) {
goto done;
}
err = _Py_PreInitializeFromPreConfig(&config);
done:
_PyPreConfig_Clear(&config);
return err;
}
static _PyInitError
pymain_init_coreconfig(_PyCoreConfig *config, const _PyArgv *args,
PyInterpreterState **interp_p)
{
_PyInitError err = _PyCoreConfig_ReadFromArgv(config, args);
if (_Py_INIT_FAILED(err)) {
return err;
}
err = _PyCoreConfig_Write(config);
if (_Py_INIT_FAILED(err)) {
return err;
}
return _Py_InitializeCore(interp_p, config);
}
static _PyInitError
pymain_init_python_main(PyInterpreterState *interp)
{
_PyInitError err;
_PyMainInterpreterConfig main_config = _PyMainInterpreterConfig_INIT;
err = _PyMainInterpreterConfig_Read(&main_config, &interp->core_config);
if (!_Py_INIT_FAILED(err)) {
err = _Py_InitializeMainInterpreter(interp, &main_config);
}
_PyMainInterpreterConfig_Clear(&main_config);
if (_Py_INIT_FAILED(err)) {
return err;
}
return _Py_INIT_OK();
}
static _PyInitError
pymain_init(const _PyArgv *args, PyInterpreterState **interp_p)
{
_PyInitError err;
err = _PyRuntime_Initialize();
if (_Py_INIT_FAILED(err)) {
return err;
}
/* 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
err = pymain_init_preconfig(args);
if (_Py_INIT_FAILED(err)) {
return err;
}
_PyCoreConfig config = _PyCoreConfig_INIT;
err = pymain_init_coreconfig(&config, args, interp_p);
if (_Py_INIT_FAILED(err)) {
goto done;
}
err = pymain_init_python_main(*interp_p);
if (_Py_INIT_FAILED(err)) {
goto done;
}
err = _Py_INIT_OK();
done:
_PyCoreConfig_Clear(&config);
return err;
}
/* --- pymain_run_python() ---------------------------------------- */
/* Non-zero if filename, command (-c) or module (-m) is set
on the command line */
#define RUN_CODE(config) \
(config->run_command != NULL || config->run_filename != NULL \
|| config->run_module != NULL)
/* Return non-zero is stdin is a TTY or if -i command line option is used */
static int
stdin_is_interactive(const _PyCoreConfig *config)
{
return (isatty(fileno(stdin)) || config->interactive);
}
static PyObject *
pymain_get_importer(const wchar_t *filename)
{
PyObject *sys_path0 = NULL, *importer;
sys_path0 = PyUnicode_FromWideChar(filename, wcslen(filename));
if (sys_path0 == NULL) {
goto error;
}
importer = PyImport_GetImporter(sys_path0);
if (importer == NULL) {
goto error;
}
if (importer == Py_None) {
Py_DECREF(sys_path0);
Py_DECREF(importer);
return NULL;
}
Py_DECREF(importer);
return sys_path0;
error:
Py_XDECREF(sys_path0);
PySys_WriteStderr("Failed checking if argv[0] is an import path entry\n");
PyErr_Print();
return NULL;
}
static int
pymain_sys_path_add_path0(PyInterpreterState *interp, PyObject *path0)
{
_Py_IDENTIFIER(path);
PyObject *sys_path;
PyObject *sysdict = interp->sysdict;
if (sysdict != NULL) {
sys_path = _PyDict_GetItemIdWithError(sysdict, &PyId_path);
if (sys_path == NULL && PyErr_Occurred()) {
goto error;
}
}
else {
sys_path = NULL;
}
if (sys_path == NULL) {
PyErr_SetString(PyExc_RuntimeError, "unable to get sys.path");
goto error;
}
if (PyList_Insert(sys_path, 0, path0)) {
goto error;
}
return 0;
error:
PyErr_Print();
return -1;
}
static void
pymain_header(const _PyCoreConfig *config)
{
if (config->quiet) {
return;
}
if (!config->verbose && (RUN_CODE(config) || !stdin_is_interactive(config))) {
return;
}
fprintf(stderr, "Python %s on %s\n", Py_GetVersion(), Py_GetPlatform());
if (config->site_import) {
fprintf(stderr, "%s\n", COPYRIGHT);
}
}
static void
pymain_import_readline(const _PyCoreConfig *config)
{
if (config->preconfig.isolated) {
return;
}
if (!config->inspect && RUN_CODE(config)) {
return;
}
if (!isatty(fileno(stdin))) {
return;
}
PyObject *mod = PyImport_ImportModule("readline");
if (mod == NULL) {
PyErr_Clear();
}
else {
Py_DECREF(mod);
}
}
static int
pymain_run_command(wchar_t *command, PyCompilerFlags *cf)
{
PyObject *unicode, *bytes;
int ret;
unicode = PyUnicode_FromWideChar(command, -1);
if (unicode == NULL) {
goto error;
}
bytes = PyUnicode_AsUTF8String(unicode);
Py_DECREF(unicode);
if (bytes == NULL) {
goto error;
}
ret = PyRun_SimpleStringFlags(PyBytes_AsString(bytes), cf);
Py_DECREF(bytes);
return (ret != 0);
error:
PySys_WriteStderr("Unable to decode the command from the command line:\n");
PyErr_Print();
return 1;
}
static int
pymain_run_module(const wchar_t *modname, int set_argv0)
{
PyObject *module, *runpy, *runmodule, *runargs, *result;
runpy = PyImport_ImportModule("runpy");
if (runpy == NULL) {
fprintf(stderr, "Could not import runpy module\n");
PyErr_Print();
return -1;
}
runmodule = PyObject_GetAttrString(runpy, "_run_module_as_main");
if (runmodule == NULL) {
fprintf(stderr, "Could not access runpy._run_module_as_main\n");
PyErr_Print();
Py_DECREF(runpy);
return -1;
}
module = PyUnicode_FromWideChar(modname, wcslen(modname));
if (module == NULL) {
fprintf(stderr, "Could not convert module name to unicode\n");
PyErr_Print();
Py_DECREF(runpy);
Py_DECREF(runmodule);
return -1;
}
runargs = Py_BuildValue("(Oi)", module, set_argv0);
if (runargs == NULL) {
fprintf(stderr,
"Could not create arguments for runpy._run_module_as_main\n");
PyErr_Print();
Py_DECREF(runpy);
Py_DECREF(runmodule);
Py_DECREF(module);
return -1;
}
result = PyObject_Call(runmodule, runargs, NULL);
if (result == NULL) {
PyErr_Print();
}
Py_DECREF(runpy);
Py_DECREF(runmodule);
Py_DECREF(module);
Py_DECREF(runargs);
if (result == NULL) {
return -1;
}
Py_DECREF(result);
return 0;
}
static int
pymain_run_file(_PyCoreConfig *config, PyCompilerFlags *cf)
{
const wchar_t *filename = config->run_filename;
FILE *fp = _Py_wfopen(filename, L"r");
if (fp == NULL) {
char *cfilename_buffer;
const char *cfilename;
int err = errno;
cfilename_buffer = _Py_EncodeLocaleRaw(filename, NULL);
if (cfilename_buffer != NULL)
cfilename = cfilename_buffer;
else
cfilename = "<unprintable file name>";
fprintf(stderr, "%ls: can't open file '%s': [Errno %d] %s\n",
config->program, cfilename, err, strerror(err));
PyMem_RawFree(cfilename_buffer);
return 2;
}
if (config->skip_source_first_line) {
int ch;
/* Push back first newline so line numbers remain the same */
while ((ch = getc(fp)) != EOF) {
if (ch == '\n') {
(void)ungetc(ch, fp);
break;
}
}
}
struct _Py_stat_struct sb;
if (_Py_fstat_noraise(fileno(fp), &sb) == 0 && S_ISDIR(sb.st_mode)) {
fprintf(stderr,
"%ls: '%ls' is a directory, cannot continue\n",
config->program, filename);
fclose(fp);
return 1;
}
/* call pending calls like signal handlers (SIGINT) */
if (Py_MakePendingCalls() == -1) {
PyErr_Print();
fclose(fp);
return 1;
}
PyObject *unicode, *bytes = NULL;
const char *filename_str;
unicode = PyUnicode_FromWideChar(filename, wcslen(filename));
if (unicode != NULL) {
bytes = PyUnicode_EncodeFSDefault(unicode);
Py_DECREF(unicode);
}
if (bytes != NULL) {
filename_str = PyBytes_AsString(bytes);
}
else {
PyErr_Clear();
filename_str = "<filename encoding error>";
}
/* PyRun_AnyFileExFlags(closeit=1) calls fclose(fp) before running code */
int run = PyRun_AnyFileExFlags(fp, filename_str, 1, cf);
Py_XDECREF(bytes);
return (run != 0);
}
static void
pymain_run_startup(_PyCoreConfig *config, PyCompilerFlags *cf)
{
const char *startup = _PyCoreConfig_GetEnv(config, "PYTHONSTARTUP");
if (startup == NULL) {
return;
}
FILE *fp = _Py_fopen(startup, "r");
if (fp == NULL) {
int save_errno = errno;
PySys_WriteStderr("Could not open PYTHONSTARTUP\n");
errno = save_errno;
PyErr_SetFromErrnoWithFilename(PyExc_OSError,
startup);
PyErr_Print();
return;
}
(void) PyRun_SimpleFileExFlags(fp, startup, 0, cf);
PyErr_Clear();
fclose(fp);
}
static void
pymain_run_interactive_hook(void)
{
PyObject *sys, *hook, *result;
sys = PyImport_ImportModule("sys");
if (sys == NULL) {
goto error;
}
hook = PyObject_GetAttrString(sys, "__interactivehook__");
Py_DECREF(sys);
if (hook == NULL) {
PyErr_Clear();
return;
}
result = _PyObject_CallNoArg(hook);
Py_DECREF(hook);
if (result == NULL) {
goto error;
}
Py_DECREF(result);
return;
error:
PySys_WriteStderr("Failed calling sys.__interactivehook__\n");
PyErr_Print();
}
static int
pymain_run_stdin(_PyCoreConfig *config, PyCompilerFlags *cf)
{
if (stdin_is_interactive(config)) {
Py_InspectFlag = 0; /* do exit on SystemExit */
config->inspect = 0;
pymain_run_startup(config, cf);
pymain_run_interactive_hook();
}
/* call pending calls like signal handlers (SIGINT) */
if (Py_MakePendingCalls() == -1) {
PyErr_Print();
return 1;
}
int run = PyRun_AnyFileExFlags(stdin, "<stdin>", 0, cf);
return (run != 0);
}
static void
pymain_repl(_PyCoreConfig *config, PyCompilerFlags *cf, int *exitcode)
{
/* Check this environment variable at the end, to give programs the
opportunity to set it from Python. */
if (!Py_InspectFlag && _PyCoreConfig_GetEnv(config, "PYTHONINSPECT")) {
Py_InspectFlag = 1;
config->inspect = 1;
}
if (!(Py_InspectFlag && stdin_is_interactive(config) && RUN_CODE(config))) {
return;
}
Py_InspectFlag = 0;
config->inspect = 0;
pymain_run_interactive_hook();
int res = PyRun_AnyFileFlags(stdin, "<stdin>", cf);
*exitcode = (res != 0);
}
static _PyInitError
pymain_run_python(PyInterpreterState *interp, int *exitcode)
{
_PyInitError err;
_PyCoreConfig *config = &interp->core_config;
PyObject *main_importer_path = NULL;
if (config->run_filename != NULL) {
/* If filename is a package (ex: directory or ZIP file) which contains
__main__.py, main_importer_path is set to filename and will be
prepended to sys.path.
Otherwise, main_importer_path is set to NULL. */
main_importer_path = pymain_get_importer(config->run_filename);
}
if (main_importer_path != NULL) {
if (pymain_sys_path_add_path0(interp, main_importer_path) < 0) {
err = _Py_INIT_EXIT(1);
goto done;
}
}
else if (!config->preconfig.isolated) {
PyObject *path0 = NULL;
if (_PyPathConfig_ComputeSysPath0(&config->argv, &path0)) {
if (path0 == NULL) {
err = _Py_INIT_NO_MEMORY();
goto done;
}
if (pymain_sys_path_add_path0(interp, path0) < 0) {
Py_DECREF(path0);
err = _Py_INIT_EXIT(1);
goto done;
}
Py_DECREF(path0);
}
}
PyCompilerFlags cf = {.cf_flags = 0, .cf_feature_version = PY_MINOR_VERSION};
pymain_header(config);
pymain_import_readline(config);
if (config->run_command) {
*exitcode = pymain_run_command(config->run_command, &cf);
}
else if (config->run_module) {
*exitcode = (pymain_run_module(config->run_module, 1) != 0);
}
else if (main_importer_path != NULL) {
int sts = pymain_run_module(L"__main__", 0);
*exitcode = (sts != 0);
}
else if (config->run_filename != NULL) {
*exitcode = pymain_run_file(config, &cf);
}
else {
*exitcode = pymain_run_stdin(config, &cf);
}
pymain_repl(config, &cf, exitcode);
err = _Py_INIT_OK();
done:
Py_XDECREF(main_importer_path);
return err;
}
/* --- pymain_main() ---------------------------------------------- */
static void
pymain_free(void)
{
_PyImport_Fini2();
/* Free global variables which cannot be freed in Py_Finalize():
configuration options set before Py_Initialize() which should
remain valid after Py_Finalize(), since
Py_Initialize()-Py_Finalize() can be called multiple times. */
_PyPathConfig_ClearGlobal();
_Py_ClearStandardStreamEncoding();
_Py_ClearArgcArgv();
_PyRuntime_Finalize();
}
static int
exit_sigint(void)
{
/* bpo-1054041: We need to exit via the
* SIG_DFL handler for SIGINT if KeyboardInterrupt went unhandled.
* If we don't, a calling process such as a shell may not know
* about the user's ^C. https://www.cons.org/cracauer/sigint.html */
#if defined(HAVE_GETPID) && !defined(MS_WINDOWS)
if (PyOS_setsig(SIGINT, SIG_DFL) == SIG_ERR) {
perror("signal"); /* Impossible in normal environments. */
} else {
kill(getpid(), SIGINT);
}
/* If setting SIG_DFL failed, or kill failed to terminate us,
* there isn't much else we can do aside from an error code. */
#endif /* HAVE_GETPID && !MS_WINDOWS */
#ifdef MS_WINDOWS
/* cmd.exe detects this, prints ^C, and offers to terminate. */
/* https://msdn.microsoft.com/en-us/library/cc704588.aspx */
return STATUS_CONTROL_C_EXIT;
#else
return SIGINT + 128;
#endif /* !MS_WINDOWS */
}
static int
pymain_main(_PyArgv *args)
{
_PyInitError err;
PyInterpreterState *interp;
err = pymain_init(args, &interp);
if (_Py_INIT_FAILED(err)) {
goto exit_init_error;
}
int exitcode = 0;
err = pymain_run_python(interp, &exitcode);
if (_Py_INIT_FAILED(err)) {
goto exit_init_error;
}
if (Py_FinalizeEx() < 0) {
/* Value unlikely to be confused with a non-error exit status or
other special meaning */
exitcode = 120;
}
pymain_free();
if (_Py_UnhandledKeyboardInterrupt) {
exitcode = exit_sigint();
}
return exitcode;
exit_init_error:
pymain_free();
_Py_ExitInitError(err);
}
int
Py_Main(int argc, wchar_t **argv)
{
_PyArgv args = {
.argc = argc,
.use_bytes_argv = 0,
.bytes_argv = NULL,
.wchar_argv = argv};
return pymain_main(&args);
}
int
_Py_UnixMain(int argc, char **argv)
{
_PyArgv args = {
.argc = argc,
.use_bytes_argv = 1,
.bytes_argv = argv,
.wchar_argv = NULL};
return pymain_main(&args);
}
#ifdef __cplusplus
}
#endif
