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/* Python interpreter main program */
#include "Python.h"
#include "pycore_initconfig.h" // _PyArgv
#include "pycore_interp.h" // _PyInterpreterState.sysdict
#include "pycore_pathconfig.h" // _PyPathConfig_ComputeSysPath0()
#include "pycore_pylifecycle.h" // _Py_PreInitializeFromPyArgv()
#include "pycore_pystate.h" // _PyInterpreterState_GET()
/* 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 MS_WINDOWS
# include <windows.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
/* --- pymain_init() ---------------------------------------------- */
static PyStatus
pymain_init(const _PyArgv *args)
{
PyStatus status;
status = _PyRuntime_Initialize();
if (_PyStatus_EXCEPTION(status)) {
return status;
}
PyPreConfig preconfig;
PyPreConfig_InitPythonConfig(&preconfig);
status = _Py_PreInitializeFromPyArgv(&preconfig, args);
if (_PyStatus_EXCEPTION(status)) {
return status;
}
PyConfig config;
PyConfig_InitPythonConfig(&config);
/* pass NULL as the config: config is read from command line arguments,
environment variables, configuration files */
if (args->use_bytes_argv) {
status = PyConfig_SetBytesArgv(&config, args->argc, args->bytes_argv);
}
else {
status = PyConfig_SetArgv(&config, args->argc, args->wchar_argv);
}
if (_PyStatus_EXCEPTION(status)) {
goto done;
}
status = Py_InitializeFromConfig(&config);
if (_PyStatus_EXCEPTION(status)) {
goto done;
}
status = _PyStatus_OK();
done:
PyConfig_Clear(&config);
return status;
}
/* --- pymain_run_python() ---------------------------------------- */
/* Non-zero if filename, command (-c) or module (-m) is set
on the command line */
static inline int config_run_code(const PyConfig *config)
{
return (config->run_command != NULL
|| config->run_filename != NULL
|| config->run_module != NULL);
}
/* Return non-zero if stdin is a TTY or if -i command line option is used */
static int
stdin_is_interactive(const PyConfig *config)
{
return (isatty(fileno(stdin)) || config->interactive);
}
/* Display the current Python exception and return an exitcode */
static int
pymain_err_print(int *exitcode_p)
{
int exitcode;
if (_Py_HandleSystemExit(&exitcode)) {
*exitcode_p = exitcode;
return 1;
}
PyErr_Print();
return 0;
}
static int
pymain_exit_err_print(void)
{
int exitcode = 1;
pymain_err_print(&exitcode);
return exitcode;
}
/* Write an exitcode into *exitcode and return 1 if we have to exit Python.
Return 0 otherwise. */
static int
pymain_get_importer(const wchar_t *filename, PyObject **importer_p, int *exitcode)
{
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 0;
}
Py_DECREF(importer);
*importer_p = sys_path0;
return 0;
error:
Py_XDECREF(sys_path0);
PySys_WriteStderr("Failed checking if argv[0] is an import path entry\n");
return pymain_err_print(exitcode);
}
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()) {
return -1;
}
}
else {
sys_path = NULL;
}
if (sys_path == NULL) {
PyErr_SetString(PyExc_RuntimeError, "unable to get sys.path");
return -1;
}
if (PyList_Insert(sys_path, 0, path0)) {
return -1;
}
return 0;
}
static void
pymain_header(const PyConfig *config)
{
if (config->quiet) {
return;
}
if (!config->verbose && (config_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 PyConfig *config)
{
if (config->isolated) {
return;
}
if (!config->inspect && config_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)
{
PyObject *unicode, *bytes;
int ret;
unicode = PyUnicode_FromWideChar(command, -1);
if (unicode == NULL) {
goto error;
}
if (PySys_Audit("cpython.run_command", "O", unicode) < 0) {
return pymain_exit_err_print();
}
bytes = PyUnicode_AsUTF8String(unicode);
Py_DECREF(unicode);
if (bytes == NULL) {
goto error;
}
PyCompilerFlags cf = _PyCompilerFlags_INIT;
cf.cf_flags |= PyCF_IGNORE_COOKIE;
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");
return pymain_exit_err_print();
}
static int
pymain_run_module(const wchar_t *modname, int set_argv0)
{
PyObject *module, *runpy, *runmodule, *runargs, *result;
if (PySys_Audit("cpython.run_module", "u", modname) < 0) {
return pymain_exit_err_print();
}
runpy = PyImport_ImportModule("runpy");
if (runpy == NULL) {
fprintf(stderr, "Could not import runpy module\n");
return pymain_exit_err_print();
}
runmodule = PyObject_GetAttrString(runpy, "_run_module_as_main");
if (runmodule == NULL) {
fprintf(stderr, "Could not access runpy._run_module_as_main\n");
Py_DECREF(runpy);
return pymain_exit_err_print();
}
module = PyUnicode_FromWideChar(modname, wcslen(modname));
if (module == NULL) {
fprintf(stderr, "Could not convert module name to unicode\n");
Py_DECREF(runpy);
Py_DECREF(runmodule);
return pymain_exit_err_print();
}
runargs = PyTuple_Pack(2, module, set_argv0 ? Py_True : Py_False);
if (runargs == NULL) {
fprintf(stderr,
"Could not create arguments for runpy._run_module_as_main\n");
Py_DECREF(runpy);
Py_DECREF(runmodule);
Py_DECREF(module);
return pymain_exit_err_print();
}
_Py_UnhandledKeyboardInterrupt = 0;
result = PyObject_Call(runmodule, runargs, NULL);
if (!result && PyErr_Occurred() == PyExc_KeyboardInterrupt) {
_Py_UnhandledKeyboardInterrupt = 1;
}
Py_DECREF(runpy);
Py_DECREF(runmodule);
Py_DECREF(module);
Py_DECREF(runargs);
if (result == NULL) {
return pymain_exit_err_print();
}
Py_DECREF(result);
return 0;
}
static int
pymain_run_file_obj(PyObject *program_name, PyObject *filename,
int skip_source_first_line)
{
if (PySys_Audit("cpython.run_file", "O", filename) < 0) {
return pymain_exit_err_print();
}
FILE *fp = _Py_fopen_obj(filename, "rb");
if (fp == NULL) {
// Ignore the OSError
PyErr_Clear();
PySys_FormatStderr("%S: can't open file %R: [Errno %d] %s\n",
program_name, filename, errno, strerror(errno));
return 2;
}
if (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)) {
PySys_FormatStderr("%S: %R is a directory, cannot continue\n",
program_name, filename);
fclose(fp);
return 1;
}
// Call pending calls like signal handlers (SIGINT)
if (Py_MakePendingCalls() == -1) {
fclose(fp);
return pymain_exit_err_print();
}
/* PyRun_AnyFileExFlags(closeit=1) calls fclose(fp) before running code */
PyCompilerFlags cf = _PyCompilerFlags_INIT;
int run = _PyRun_AnyFileObject(fp, filename, 1, &cf);
return (run != 0);
}
static int
pymain_run_file(const PyConfig *config)
{
PyObject *filename = PyUnicode_FromWideChar(config->run_filename, -1);
if (filename == NULL) {
PyErr_Print();
return -1;
}
PyObject *program_name = PyUnicode_FromWideChar(config->program_name, -1);
if (program_name == NULL) {
Py_DECREF(filename);
PyErr_Print();
return -1;
}
int res = pymain_run_file_obj(program_name, filename,
config->skip_source_first_line);
Py_DECREF(filename);
Py_DECREF(program_name);
return res;
}
static int
pymain_run_startup(PyConfig *config, int *exitcode)
{
int ret;
if (!config->use_environment) {
return 0;
}
PyObject *startup = NULL;
#ifdef MS_WINDOWS
const wchar_t *env = _wgetenv(L"PYTHONSTARTUP");
if (env == NULL || env[0] == L'\0') {
return 0;
}
startup = PyUnicode_FromWideChar(env, wcslen(env));
if (startup == NULL) {
goto error;
}
#else
const char *env = _Py_GetEnv(config->use_environment, "PYTHONSTARTUP");
if (env == NULL) {
return 0;
}
startup = PyUnicode_DecodeFSDefault(env);
if (startup == NULL) {
goto error;
}
#endif
if (PySys_Audit("cpython.run_startup", "O", startup) < 0) {
goto error;
}
FILE *fp = _Py_fopen_obj(startup, "r");
if (fp == NULL) {
int save_errno = errno;
PyErr_Clear();
PySys_WriteStderr("Could not open PYTHONSTARTUP\n");
errno = save_errno;
PyErr_SetFromErrnoWithFilenameObjects(PyExc_OSError, startup, NULL);
goto error;
}
PyCompilerFlags cf = _PyCompilerFlags_INIT;
(void) _PyRun_SimpleFileObject(fp, startup, 0, &cf);
PyErr_Clear();
fclose(fp);
ret = 0;
done:
Py_XDECREF(startup);
return ret;
error:
ret = pymain_err_print(exitcode);
goto done;
}
/* Write an exitcode into *exitcode and return 1 if we have to exit Python.
Return 0 otherwise. */
static int
pymain_run_interactive_hook(int *exitcode)
{
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 0;
}
if (PySys_Audit("cpython.run_interactivehook", "O", hook) < 0) {
goto error;
}
result = _PyObject_CallNoArg(hook);
Py_DECREF(hook);
if (result == NULL) {
goto error;
}
Py_DECREF(result);
return 0;
error:
PySys_WriteStderr("Failed calling sys.__interactivehook__\n");
return pymain_err_print(exitcode);
}
static int
pymain_run_stdin(PyConfig *config)
{
if (stdin_is_interactive(config)) {
config->inspect = 0;
Py_InspectFlag = 0; /* do exit on SystemExit */
int exitcode;
if (pymain_run_startup(config, &exitcode)) {
return exitcode;
}
if (pymain_run_interactive_hook(&exitcode)) {
return exitcode;
}
}
/* call pending calls like signal handlers (SIGINT) */
if (Py_MakePendingCalls() == -1) {
return pymain_exit_err_print();
}
if (PySys_Audit("cpython.run_stdin", NULL) < 0) {
return pymain_exit_err_print();
}
PyCompilerFlags cf = _PyCompilerFlags_INIT;
int run = PyRun_AnyFileExFlags(stdin, "<stdin>", 0, &cf);
return (run != 0);
}
static void
pymain_repl(PyConfig *config, int *exitcode)
{
/* Check this environment variable at the end, to give programs the
opportunity to set it from Python. */
if (!config->inspect && _Py_GetEnv(config->use_environment, "PYTHONINSPECT")) {
config->inspect = 1;
Py_InspectFlag = 1;
}
if (!(config->inspect && stdin_is_interactive(config) && config_run_code(config))) {
return;
}
config->inspect = 0;
Py_InspectFlag = 0;
if (pymain_run_interactive_hook(exitcode)) {
return;
}
PyCompilerFlags cf = _PyCompilerFlags_INIT;
int res = PyRun_AnyFileFlags(stdin, "<stdin>", &cf);
*exitcode = (res != 0);
}
static void
pymain_run_python(int *exitcode)
{
PyInterpreterState *interp = _PyInterpreterState_GET();
/* pymain_run_stdin() modify the config */
PyConfig *config = (PyConfig*)_PyInterpreterState_GetConfig(interp);
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 left unchanged. */
if (pymain_get_importer(config->run_filename, &main_importer_path,
exitcode)) {
return;
}
}
if (main_importer_path != NULL) {
if (pymain_sys_path_add_path0(interp, main_importer_path) < 0) {
goto error;
}
}
else if (!config->isolated) {
PyObject *path0 = NULL;
int res = _PyPathConfig_ComputeSysPath0(&config->argv, &path0);
if (res < 0) {
goto error;
}
if (res > 0) {
if (pymain_sys_path_add_path0(interp, path0) < 0) {
Py_DECREF(path0);
goto error;
}
Py_DECREF(path0);
}
}
pymain_header(config);
pymain_import_readline(config);
if (config->run_command) {
*exitcode = pymain_run_command(config->run_command);
}
else if (config->run_module) {
*exitcode = pymain_run_module(config->run_module, 1);
}
else if (main_importer_path != NULL) {
*exitcode = pymain_run_module(L"__main__", 0);
}
else if (config->run_filename != NULL) {
*exitcode = pymain_run_file(config);
}
else {
*exitcode = pymain_run_stdin(config);
}
pymain_repl(config, exitcode);
goto done;
error:
*exitcode = pymain_exit_err_print();
done:
Py_XDECREF(main_importer_path);
}
/* --- 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 void _Py_NO_RETURN
pymain_exit_error(PyStatus status)
{
if (_PyStatus_IS_EXIT(status)) {
/* If it's an error rather than a regular exit, leave Python runtime
alive: Py_ExitStatusException() uses the current exception and use
sys.stdout in this case. */
pymain_free();
}
Py_ExitStatusException(status);
}
int
Py_RunMain(void)
{
int exitcode = 0;
pymain_run_python(&exitcode);
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;
}
static int
pymain_main(_PyArgv *args)
{
PyStatus status = pymain_init(args);
if (_PyStatus_IS_EXIT(status)) {
pymain_free();
return status.exitcode;
}
if (_PyStatus_EXCEPTION(status)) {
pymain_exit_error(status);
}
return Py_RunMain();
}
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_BytesMain(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
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