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

#include "Python.h"

#include "osdefs.h" // DELIM

#include "pycore_initconfig.h"

#include "pycore_fileutils.h"

#include "pycore_pathconfig.h"

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

#include <wchar.h>

#ifdef MS_WINDOWS

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

#endif

#ifdef __cplusplus

extern "C" {

#endif

_PyPathConfig _Py_path_config = _PyPathConfig_INIT;

static int

copy_wstr(wchar_t **dst, const wchar_t *src)

{

assert(*dst == NULL);

if (src != NULL) {

*dst = _PyMem_RawWcsdup(src);

if (*dst == NULL) {

return -1;

}

}

else {

*dst = NULL;

}

return 0;

}

static void

pathconfig_clear(_PyPathConfig *config)

{

/* _PyMem_SetDefaultAllocator() is needed to get a known memory allocator,

since Py_SetPath(), Py_SetPythonHome() and Py_SetProgramName() can be

called before Py_Initialize() which can changes the memory allocator. */

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

#define CLEAR(ATTR) \

do { \

PyMem_RawFree(ATTR); \

ATTR = NULL; \

} while (0)

CLEAR(config->program_full_path);

CLEAR(config->prefix);

CLEAR(config->exec_prefix);

CLEAR(config->module_search_path);

CLEAR(config->program_name);

CLEAR(config->home);

#ifdef MS_WINDOWS

CLEAR(config->base_executable);

#endif

#undef CLEAR

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

}

static PyStatus

pathconfig_copy(_PyPathConfig *config, const _PyPathConfig *config2)

{

pathconfig_clear(config);

#define COPY_ATTR(ATTR) \

do { \

if (copy_wstr(&config->ATTR, config2->ATTR) < 0) { \

return _PyStatus_NO_MEMORY(); \

} \

} while (0)

COPY_ATTR(program_full_path);

COPY_ATTR(prefix);

COPY_ATTR(exec_prefix);

COPY_ATTR(module_search_path);

COPY_ATTR(program_name);

COPY_ATTR(home);

#ifdef MS_WINDOWS

config->isolated = config2->isolated;

config->site_import = config2->site_import;

COPY_ATTR(base_executable);

#endif

#undef COPY_ATTR

return _PyStatus_OK();

}

void

_PyPathConfig_ClearGlobal(void)

{

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

pathconfig_clear(&_Py_path_config);

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

}

static wchar_t*

_PyWideStringList_Join(const PyWideStringList *list, wchar_t sep)

{

size_t len = 1; /* NUL terminator */

for (Py_ssize_t i=0; i < list->length; i++) {

if (i != 0) {

len++;

}

len += wcslen(list->items[i]);

}

wchar_t *text = PyMem_RawMalloc(len * sizeof(wchar_t));

if (text == NULL) {

return NULL;

}

wchar_t *str = text;

for (Py_ssize_t i=0; i < list->length; i++) {

wchar_t *path = list->items[i];

if (i != 0) {

*str++ = sep;

}

len = wcslen(path);

memcpy(str, path, len * sizeof(wchar_t));

str += len;

}

*str = L'\0';

return text;

}

static PyStatus

pathconfig_set_from_config(_PyPathConfig *pathconfig, const PyConfig *config)

{

PyStatus status;

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

if (config->module_search_paths_set) {

PyMem_RawFree(pathconfig->module_search_path);

pathconfig->module_search_path = _PyWideStringList_Join(&config->module_search_paths, DELIM);

if (pathconfig->module_search_path == NULL) {

goto no_memory;

}

}

#define COPY_CONFIG(PATH_ATTR, CONFIG_ATTR) \

if (config->CONFIG_ATTR) { \

PyMem_RawFree(pathconfig->PATH_ATTR); \

pathconfig->PATH_ATTR = NULL; \

if (copy_wstr(&pathconfig->PATH_ATTR, config->CONFIG_ATTR) < 0) { \

goto no_memory; \

} \

}

COPY_CONFIG(program_full_path, executable);

COPY_CONFIG(prefix, prefix);

COPY_CONFIG(exec_prefix, exec_prefix);

COPY_CONFIG(program_name, program_name);

COPY_CONFIG(home, home);

#ifdef MS_WINDOWS

COPY_CONFIG(base_executable, base_executable);

#endif

#undef COPY_CONFIG

status = _PyStatus_OK();

goto done;

no_memory:

status = _PyStatus_NO_MEMORY();

done:

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

return status;

}

PyObject *

_PyPathConfig_AsDict(void)

{

PyObject *dict = PyDict_New();

if (dict == NULL) {

return NULL;

}

#define SET_ITEM(KEY, EXPR) \

do { \

PyObject *obj = (EXPR); \

if (obj == NULL) { \

goto fail; \

} \

int res = PyDict_SetItemString(dict, KEY, obj); \

Py_DECREF(obj); \

if (res < 0) { \

goto fail; \

} \

} while (0)

#define SET_ITEM_STR(KEY) \

SET_ITEM(#KEY, \

(_Py_path_config.KEY \

? PyUnicode_FromWideChar(_Py_path_config.KEY, -1) \

: (Py_INCREF(Py_None), Py_None)))

#define SET_ITEM_INT(KEY) \

SET_ITEM(#KEY, PyLong_FromLong(_Py_path_config.KEY))

SET_ITEM_STR(program_full_path);

SET_ITEM_STR(prefix);

SET_ITEM_STR(exec_prefix);

SET_ITEM_STR(module_search_path);

SET_ITEM_STR(program_name);

SET_ITEM_STR(home);

#ifdef MS_WINDOWS

SET_ITEM_INT(isolated);

SET_ITEM_INT(site_import);

SET_ITEM_STR(base_executable);

{

wchar_t py3path[MAX_PATH];

HMODULE hPython3 = GetModuleHandleW(PY3_DLLNAME);

PyObject *obj;

if (hPython3

&& GetModuleFileNameW(hPython3, py3path, Py_ARRAY_LENGTH(py3path)))

{

obj = PyUnicode_FromWideChar(py3path, -1);

if (obj == NULL) {

goto fail;

}

}

else {

obj = Py_None;

Py_INCREF(obj);

}

if (PyDict_SetItemString(dict, "python3_dll", obj) < 0) {

Py_DECREF(obj);

goto fail;

}

Py_DECREF(obj);

}

#endif

#undef SET_ITEM

#undef SET_ITEM_STR

#undef SET_ITEM_INT

return dict;

fail:

Py_DECREF(dict);

return NULL;

}

PyStatus

_PyConfig_WritePathConfig(const PyConfig *config)

{

return pathconfig_set_from_config(&_Py_path_config, config);

}

static PyStatus

config_init_module_search_paths(PyConfig *config, _PyPathConfig *pathconfig)

{

assert(!config->module_search_paths_set);

_PyWideStringList_Clear(&config->module_search_paths);

const wchar_t *sys_path = pathconfig->module_search_path;

const wchar_t delim = DELIM;

while (1) {

const wchar_t *p = wcschr(sys_path, delim);

if (p == NULL) {

p = sys_path + wcslen(sys_path); /* End of string */

}

size_t path_len = (p - sys_path);

wchar_t *path = PyMem_RawMalloc((path_len + 1) * sizeof(wchar_t));

if (path == NULL) {

return _PyStatus_NO_MEMORY();

}

memcpy(path, sys_path, path_len * sizeof(wchar_t));

path[path_len] = L'\0';

PyStatus status = PyWideStringList_Append(&config->module_search_paths, path);

PyMem_RawFree(path);

if (_PyStatus_EXCEPTION(status)) {

return status;

}

if (*p == '\0') {

break;

}

sys_path = p + 1;

}

config->module_search_paths_set = 1;

return _PyStatus_OK();

}

/* Calculate the path configuration:

- exec_prefix

- module_search_path

- prefix

- program_full_path

On Windows, more fields are calculated:

- base_executable

- isolated

- site_import

On other platforms, isolated and site_import are left unchanged, and

_PyConfig_InitPathConfig() copies executable to base_executable (if it's not

set).

Priority, highest to lowest:

- PyConfig

- _Py_path_config: set by Py_SetPath(), Py_SetPythonHome()

and Py_SetProgramName()

- _PyPathConfig_Calculate()

*/

static PyStatus

pathconfig_init(_PyPathConfig *pathconfig, const PyConfig *config,

int compute_path_config)

{

PyStatus status;

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

status = pathconfig_copy(pathconfig, &_Py_path_config);

if (_PyStatus_EXCEPTION(status)) {

goto done;

}

status = pathconfig_set_from_config(pathconfig, config);

if (_PyStatus_EXCEPTION(status)) {

goto done;

}

if (compute_path_config) {

status = _PyPathConfig_Calculate(pathconfig, config);

}

done:

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

return status;

}

static PyStatus

config_init_pathconfig(PyConfig *config, int compute_path_config)

{

_PyPathConfig pathconfig = _PyPathConfig_INIT;

PyStatus status;

status = pathconfig_init(&pathconfig, config, compute_path_config);

if (_PyStatus_EXCEPTION(status)) {

goto done;

}

if (!config->module_search_paths_set

&& pathconfig.module_search_path != NULL)

{

status = config_init_module_search_paths(config, &pathconfig);

if (_PyStatus_EXCEPTION(status)) {

goto done;

}

}

#define COPY_ATTR(PATH_ATTR, CONFIG_ATTR) \

if (config->CONFIG_ATTR == NULL && pathconfig.PATH_ATTR != NULL) { \

if (copy_wstr(&config->CONFIG_ATTR, pathconfig.PATH_ATTR) < 0) { \

goto no_memory; \

} \

}

#ifdef MS_WINDOWS

if (config->executable != NULL && config->base_executable == NULL) {

/* If executable is set explicitly in the configuration,

ignore calculated base_executable: _PyConfig_InitPathConfig()

will copy executable to base_executable */

}

else {

COPY_ATTR(base_executable, base_executable);

}

#endif

COPY_ATTR(program_full_path, executable);

COPY_ATTR(prefix, prefix);

COPY_ATTR(exec_prefix, exec_prefix);

#undef COPY_ATTR

#ifdef MS_WINDOWS

/* If a ._pth file is found: isolated and site_import are overriden */

if (pathconfig.isolated != -1) {

config->isolated = pathconfig.isolated;

}

if (pathconfig.site_import != -1) {

config->site_import = pathconfig.site_import;

}

#endif

status = _PyStatus_OK();

goto done;

no_memory:

status = _PyStatus_NO_MEMORY();

done:

pathconfig_clear(&pathconfig);

return status;

}

PyStatus

_PyConfig_InitPathConfig(PyConfig *config, int compute_path_config)

{

/* Do we need to calculate the path? */

if (!config->module_search_paths_set

|| config->executable == NULL

|| config->prefix == NULL

|| config->exec_prefix == NULL)

{

PyStatus status = config_init_pathconfig(config, compute_path_config);

if (_PyStatus_EXCEPTION(status)) {

return status;

}

}

if (config->base_prefix == NULL && config->prefix != NULL) {

if (copy_wstr(&config->base_prefix, config->prefix) < 0) {

return _PyStatus_NO_MEMORY();

}

}

if (config->base_exec_prefix == NULL && config->exec_prefix != NULL) {

if (copy_wstr(&config->base_exec_prefix,

config->exec_prefix) < 0) {

return _PyStatus_NO_MEMORY();

}

}

if (config->base_executable == NULL && config->executable != NULL) {

if (copy_wstr(&config->base_executable,

config->executable) < 0) {

return _PyStatus_NO_MEMORY();

}

}

return _PyStatus_OK();

}

/* External interface */

static void _Py_NO_RETURN

path_out_of_memory(const char *func)

{

_Py_FatalErrorFunc(func, "out of memory");

}

void

Py_SetPath(const wchar_t *path)

{

if (path == NULL) {

pathconfig_clear(&_Py_path_config);

return;

}

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

PyMem_RawFree(_Py_path_config.prefix);

PyMem_RawFree(_Py_path_config.exec_prefix);

PyMem_RawFree(_Py_path_config.module_search_path);

_Py_path_config.prefix = _PyMem_RawWcsdup(L"");

_Py_path_config.exec_prefix = _PyMem_RawWcsdup(L"");

_Py_path_config.module_search_path = _PyMem_RawWcsdup(path);

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

if (_Py_path_config.prefix == NULL

|| _Py_path_config.exec_prefix == NULL

|| _Py_path_config.module_search_path == NULL)

{

path_out_of_memory(__func__);

}

}

void

Py_SetPythonHome(const wchar_t *home)

{

if (home == NULL) {

return;

}

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

PyMem_RawFree(_Py_path_config.home);

_Py_path_config.home = _PyMem_RawWcsdup(home);

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

if (_Py_path_config.home == NULL) {

path_out_of_memory(__func__);

}

}

void

Py_SetProgramName(const wchar_t *program_name)

{

if (program_name == NULL || program_name[0] == L'\0') {

return;

}

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

PyMem_RawFree(_Py_path_config.program_name);

_Py_path_config.program_name = _PyMem_RawWcsdup(program_name);

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

if (_Py_path_config.program_name == NULL) {

path_out_of_memory(__func__);

}

}

void

_Py_SetProgramFullPath(const wchar_t *program_full_path)

{

if (program_full_path == NULL || program_full_path[0] == L'\0') {

return;

}

PyMemAllocatorEx old_alloc;

_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

PyMem_RawFree(_Py_path_config.program_full_path);

_Py_path_config.program_full_path = _PyMem_RawWcsdup(program_full_path);

PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);

if (_Py_path_config.program_full_path == NULL) {

path_out_of_memory(__func__);

}

}

wchar_t *

Py_GetPath(void)

{

return _Py_path_config.module_search_path;

}

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;

}

#ifdef MS_WINDOWS

#define WCSTOK wcstok_s

#else

#define WCSTOK wcstok

#endif

/* Search for a prefix value in an environment file (pyvenv.cfg).

- If found, copy it into *value_p: string which must be freed by

PyMem_RawFree().

- If not found, *value_p is set to NULL.

*/

PyStatus

_Py_FindEnvConfigValue(FILE *env_file, const wchar_t *key,

wchar_t **value_p)

{

*value_p = NULL;

char buffer[MAXPATHLEN * 2 + 1]; /* allow extra for key, '=', etc. */

buffer[Py_ARRAY_LENGTH(buffer)-1] = '\0';

while (!feof(env_file)) {

char * p = fgets(buffer, Py_ARRAY_LENGTH(buffer) - 1, env_file);

if (p == NULL) {

break;

}

size_t n = strlen(p);

if (p[n - 1] != '\n') {

/* line has overflowed - bail */

break;

}

if (p[0] == '#') {

/* Comment - skip */

continue;

}

wchar_t *tmpbuffer = _Py_DecodeUTF8_surrogateescape(buffer, n, NULL);

if (tmpbuffer) {

wchar_t * state;

wchar_t * tok = WCSTOK(tmpbuffer, L" \t\r\n", &state);

if ((tok != NULL) && !wcscmp(tok, key)) {

tok = WCSTOK(NULL, L" \t", &state);

if ((tok != NULL) && !wcscmp(tok, L"=")) {

tok = WCSTOK(NULL, L"\r\n", &state);

if (tok != NULL) {

*value_p = _PyMem_RawWcsdup(tok);

PyMem_RawFree(tmpbuffer);

if (*value_p == NULL) {

return _PyStatus_NO_MEMORY();

}

/* found */

return _PyStatus_OK();

}

}

}

PyMem_RawFree(tmpbuffer);

}

}

/* not found */

return _PyStatus_OK();

}

#ifdef __cplusplus

}

#endif