/* Path configuration like module_search_path (sys.path) */

#include "Python.h"

#include "pycore_initconfig.h" // _PyStatus_OK()

#include "pycore_fileutils.h" // _Py_wgetcwd()

#include "pycore_pathconfig.h"

#include "pycore_pymem.h" // _PyMem_DefaultRawFree()

#include <wchar.h>

#include "marshal.h" // PyMarshal_ReadObjectFromString

#include "osdefs.h" // DELIM

#ifdef MS_WINDOWS

# include <windows.h> // GetFullPathNameW(), MAX_PATH

# include <pathcch.h>

# include <shlwapi.h>

#endif

/* External interface */

/* Stored values set by C API functions */

typedef struct _PyPathConfig {

/* Full path to the Python program */

wchar_t *program_full_path;

wchar_t *prefix;

wchar_t *exec_prefix;

wchar_t *stdlib_dir;

/* Set by Py_SetPath */

wchar_t *module_search_path;

/* Set by _PyPathConfig_UpdateGlobal */

wchar_t *calculated_module_search_path;

/* Python program name */

wchar_t *program_name;

/* Set by Py_SetPythonHome() or PYTHONHOME environment variable */

wchar_t *home;

int _is_python_build;

} _PyPathConfig;

# define _PyPathConfig_INIT \

{.module_search_path = NULL, ._is_python_build = 0}

_PyPathConfig _Py_path_config = _PyPathConfig_INIT;

const wchar_t *

_PyPathConfig_GetGlobalModuleSearchPath(void)

{

return _Py_path_config.module_search_path;

}

void

_PyPathConfig_ClearGlobal(void)

{

#define CLEAR(ATTR) \

do { \

_PyMem_DefaultRawFree(_Py_path_config.ATTR); \

_Py_path_config.ATTR = NULL; \

} while (0)

CLEAR(program_full_path);

CLEAR(prefix);

CLEAR(exec_prefix);

CLEAR(stdlib_dir);

CLEAR(module_search_path);

CLEAR(calculated_module_search_path);

CLEAR(program_name);

CLEAR(home);

_Py_path_config._is_python_build = 0;

#undef CLEAR

}

PyStatus

_PyPathConfig_ReadGlobal(PyConfig *config)

{

PyStatus status = _PyStatus_OK();

#define COPY(ATTR) \

do { \

if (_Py_path_config.ATTR && !config->ATTR) { \

status = PyConfig_SetString(config, &config->ATTR, _Py_path_config.ATTR); \

if (_PyStatus_EXCEPTION(status)) goto done; \

} \

} while (0)

#define COPY2(ATTR, SRCATTR) \

do { \

if (_Py_path_config.SRCATTR && !config->ATTR) { \

status = PyConfig_SetString(config, &config->ATTR, _Py_path_config.SRCATTR); \

if (_PyStatus_EXCEPTION(status)) goto done; \

} \

} while (0)

#define COPY_INT(ATTR) \

do { \

assert(_Py_path_config.ATTR >= 0); \

if ((_Py_path_config.ATTR >= 0) && (config->ATTR <= 0)) { \

config->ATTR = _Py_path_config.ATTR; \

} \

} while (0)

COPY(prefix);

COPY(exec_prefix);

COPY(stdlib_dir);

COPY(program_name);

COPY(home);

COPY2(executable, program_full_path);

COPY_INT(_is_python_build);

// module_search_path must be initialised - not read

#undef COPY

#undef COPY2

#undef COPY_INT

done:

return status;

}

PyStatus

_PyPathConfig_UpdateGlobal(const PyConfig *config)

{

#define COPY(ATTR) \

do { \

if (config->ATTR) { \

_PyMem_DefaultRawFree(_Py_path_config.ATTR); \

_Py_path_config.ATTR = _PyMem_DefaultRawWcsdup(config->ATTR); \

if (!_Py_path_config.ATTR) goto error; \

} \

} while (0)

#define COPY2(ATTR, SRCATTR) \

do { \

if (config->SRCATTR) { \

_PyMem_DefaultRawFree(_Py_path_config.ATTR); \

_Py_path_config.ATTR = _PyMem_DefaultRawWcsdup(config->SRCATTR); \

if (!_Py_path_config.ATTR) goto error; \

} \

} while (0)

#define COPY_INT(ATTR) \

do { \

if (config->ATTR > 0) { \

_Py_path_config.ATTR = config->ATTR; \

} \

} while (0)

COPY(prefix);

COPY(exec_prefix);

COPY(stdlib_dir);

COPY(program_name);

COPY(home);

COPY2(program_full_path, executable);

COPY_INT(_is_python_build);

#undef COPY

#undef COPY2

#undef COPY_INT

_PyMem_DefaultRawFree(_Py_path_config.module_search_path);

_Py_path_config.module_search_path = NULL;

_PyMem_DefaultRawFree(_Py_path_config.calculated_module_search_path);

_Py_path_config.calculated_module_search_path = NULL;

do {

size_t cch = 1;

for (Py_ssize_t i = 0; i < config->module_search_paths.length; ++i) {

cch += 1 + wcslen(config->module_search_paths.items[i]);

}

wchar_t *path = (wchar_t*)_PyMem_DefaultRawMalloc(sizeof(wchar_t) * cch);

if (!path) {

goto error;

}

wchar_t *p = path;

for (Py_ssize_t i = 0; i < config->module_search_paths.length; ++i) {

wcscpy(p, config->module_search_paths.items[i]);

p = wcschr(p, L'\0');

*p++ = DELIM;

*p = L'\0';

}

do {

*p = L'\0';

} while (p != path && *--p == DELIM);

_Py_path_config.calculated_module_search_path = path;

} while (0);

return _PyStatus_OK();

error:

return _PyStatus_NO_MEMORY();

}

static void _Py_NO_RETURN

path_out_of_memory(const char *func)

{

_Py_FatalErrorFunc(func, "out of memory");

}

// Removed in Python 3.13 API, but kept for the stable ABI

PyAPI_FUNC(void)

Py_SetPath(const wchar_t *path)

{

if (path == NULL) {

_PyPathConfig_ClearGlobal();

return;

}

_PyMem_DefaultRawFree(_Py_path_config.prefix);

_PyMem_DefaultRawFree(_Py_path_config.exec_prefix);

_PyMem_DefaultRawFree(_Py_path_config.stdlib_dir);

_PyMem_DefaultRawFree(_Py_path_config.module_search_path);

_PyMem_DefaultRawFree(_Py_path_config.calculated_module_search_path);

_Py_path_config.prefix = _PyMem_DefaultRawWcsdup(L"");

_Py_path_config.exec_prefix = _PyMem_DefaultRawWcsdup(L"");

// XXX Copy this from the new module_search_path?

if (_Py_path_config.home != NULL) {

_Py_path_config.stdlib_dir = _PyMem_DefaultRawWcsdup(_Py_path_config.home);

}

else {

_Py_path_config.stdlib_dir = _PyMem_DefaultRawWcsdup(L"");

}

_Py_path_config.module_search_path = _PyMem_DefaultRawWcsdup(path);

_Py_path_config.calculated_module_search_path = NULL;

if (_Py_path_config.prefix == NULL

|| _Py_path_config.exec_prefix == NULL

|| _Py_path_config.stdlib_dir == NULL

|| _Py_path_config.module_search_path == NULL)

{

path_out_of_memory(__func__);

}

}

void

Py_SetPythonHome(const wchar_t *home)

{

int has_value = home && home[0];

_PyMem_DefaultRawFree(_Py_path_config.home);

_Py_path_config.home = NULL;

if (has_value) {

_Py_path_config.home = _PyMem_DefaultRawWcsdup(home);

}

if (has_value && _Py_path_config.home == NULL) {

path_out_of_memory(__func__);

}

}

void

Py_SetProgramName(const wchar_t *program_name)

{

int has_value = program_name && program_name[0];

_PyMem_DefaultRawFree(_Py_path_config.program_name);

_Py_path_config.program_name = NULL;

if (has_value) {

_Py_path_config.program_name = _PyMem_DefaultRawWcsdup(program_name);

}

if (has_value && _Py_path_config.program_name == NULL) {

path_out_of_memory(__func__);

}

}

wchar_t *

Py_GetPath(void)

{

/* If the user has provided a path, return that */

if (_Py_path_config.module_search_path) {

return _Py_path_config.module_search_path;

}

/* If we have already done calculations, return the calculated path */

return _Py_path_config.calculated_module_search_path;

}

wchar_t *

_Py_GetStdlibDir(void)

{

wchar_t *stdlib_dir = _Py_path_config.stdlib_dir;

if (stdlib_dir != NULL && stdlib_dir[0] != L'\0') {

return stdlib_dir;

}

return NULL;

}

wchar_t *

Py_GetPrefix(void)

{

return _Py_path_config.prefix;

}

wchar_t *

Py_GetExecPrefix(void)

{

return _Py_path_config.exec_prefix;

}

wchar_t *

Py_GetProgramFullPath(void)

{

return _Py_path_config.program_full_path;

}

wchar_t*

Py_GetPythonHome(void)

{

return _Py_path_config.home;

}

wchar_t *

Py_GetProgramName(void)

{

return _Py_path_config.program_name;

}

/* Compute module search path from argv[0] or the current working

directory ("-m module" case) which will be prepended to sys.argv:

sys.path[0].

Return 1 if the path is correctly resolved and written into *path0_p.

Return 0 if it fails to resolve the full path. For example, return 0 if the

current working directory has been removed (bpo-36236) or if argv is empty.

Raise an exception and return -1 on error.

*/

int

_PyPathConfig_ComputeSysPath0(const PyWideStringList *argv, PyObject **path0_p)

{

assert(_PyWideStringList_CheckConsistency(argv));

if (argv->length == 0) {

/* Leave sys.path unchanged if sys.argv is empty */

return 0;

}

wchar_t *argv0 = argv->items[0];

int have_module_arg = (wcscmp(argv0, L"-m") == 0);

int have_script_arg = (!have_module_arg && (wcscmp(argv0, L"-c") != 0));

wchar_t *path0 = argv0;

Py_ssize_t n = 0;

#ifdef HAVE_REALPATH

wchar_t fullpath[MAXPATHLEN];

#elif defined(MS_WINDOWS)

wchar_t fullpath[MAX_PATH];

#endif

if (have_module_arg) {

#if defined(HAVE_REALPATH) || defined(MS_WINDOWS)

if (!_Py_wgetcwd(fullpath, Py_ARRAY_LENGTH(fullpath))) {

return 0;

}

path0 = fullpath;

#else

path0 = L".";

#endif

n = wcslen(path0);

}

#ifdef HAVE_READLINK

wchar_t link[MAXPATHLEN + 1];

int nr = 0;

wchar_t path0copy[2 * MAXPATHLEN + 1];

if (have_script_arg) {

nr = _Py_wreadlink(path0, link, Py_ARRAY_LENGTH(link));

}

if (nr > 0) {

/* It's a symlink */

link[nr] = '\0';

if (link[0] == SEP) {

path0 = link; /* Link to absolute path */

}

else if (wcschr(link, SEP) == NULL) {

/* Link without path */

}

else {

/* Must join(dirname(path0), link) */

wchar_t *q = wcsrchr(path0, SEP);

if (q == NULL) {

/* path0 without path */

path0 = link;

}

else {

/* Must make a copy, path0copy has room for 2 * MAXPATHLEN */

wcsncpy(path0copy, path0, MAXPATHLEN);

q = wcsrchr(path0copy, SEP);

wcsncpy(q+1, link, MAXPATHLEN);

q[MAXPATHLEN + 1] = L'\0';

path0 = path0copy;

}

}

}

#endif /* HAVE_READLINK */

wchar_t *p = NULL;

#if SEP == '\\'

/* Special case for Microsoft filename syntax */

if (have_script_arg) {

wchar_t *q;

#if defined(MS_WINDOWS)

/* Replace the first element in argv with the full path. */

wchar_t *ptemp;

if (GetFullPathNameW(path0,

Py_ARRAY_LENGTH(fullpath),

fullpath,

&ptemp)) {

path0 = fullpath;

}

#endif

p = wcsrchr(path0, SEP);

/* Test for alternate separator */

q = wcsrchr(p ? p : path0, '/');

if (q != NULL)

p = q;

if (p != NULL) {

n = p + 1 - path0;

if (n > 1 && p[-1] != ':')

n--; /* Drop trailing separator */

}

}

#else

/* All other filename syntaxes */

if (have_script_arg) {

#if defined(HAVE_REALPATH)

if (_Py_wrealpath(path0, fullpath, Py_ARRAY_LENGTH(fullpath))) {

path0 = fullpath;

}

#endif

p = wcsrchr(path0, SEP);

}

if (p != NULL) {

n = p + 1 - path0;

#if SEP == '/' /* Special case for Unix filename syntax */

if (n > 1) {

/* Drop trailing separator */

n--;

}

#endif /* Unix */

}

#endif /* All others */

PyObject *path0_obj = PyUnicode_FromWideChar(path0, n);

if (path0_obj == NULL) {

return -1;

}

*path0_p = path0_obj;

return 1;

}