mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-09 20:35:26 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 11
cpython/Python/pathconfig.c
Victor Stinner bdace21b76 bpo-38304: Remove PyConfig.struct_size (GH-16500) 
For now, we'll rely on the fact that the config structures aren't covered by the stable ABI.

We may revisit this in the future if we further explore the idea of offering a stable embedding API.
2019-10-01 08:46:42 +10:00

837 lines
20 KiB
C
Raw Blame History

/* Path configuration like module_search_path (sys.path) */
#include "Python.h"
#include "osdefs.h"
#include "pycore_initconfig.h"
#include "pycore_fileutils.h"
#include "pycore_pathconfig.h"
#include "pycore_pymem.h"
#include "pycore_pystate.h"
#include <wchar.h>
#ifdef __cplusplus
extern "C" {
#endif
_PyPathConfig _Py_path_config = _PyPathConfig_INIT;
#ifdef MS_WINDOWS
wchar_t *_Py_dll_path = NULL;
#endif
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);
#ifdef MS_WINDOWS
PyMem_RawFree(_Py_dll_path);
_Py_dll_path = NULL;
#endif
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;
}
#ifdef MS_WINDOWS
/* Initialize _Py_dll_path on Windows. Do nothing on other platforms. */
static PyStatus
_PyPathConfig_InitDLLPath(void)
{
if (_Py_dll_path == NULL) {
/* Already set: nothing to do */
return _PyStatus_OK();
}
PyMemAllocatorEx old_alloc;
_PyMem_SetDefaultAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
_Py_dll_path = _Py_GetDLLPath();
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
if (_Py_dll_path == NULL) {
return _PyStatus_NO_MEMORY();
}
return _PyStatus_OK();
}
#endif
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;
}
PyStatus
_PyConfig_WritePathConfig(const PyConfig *config)
{
#ifdef MS_WINDOWS
PyStatus status = _PyPathConfig_InitDLLPath();
if (_PyStatus_EXCEPTION(status)) {
return status;
}
#endif
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;
const wchar_t *p = sys_path;
while (1) {
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_calculate(_PyPathConfig *pathconfig, const PyConfig *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 (_Py_path_config.module_search_path == NULL) {
status = _PyPathConfig_Calculate(pathconfig, config);
}
else {
/* Py_SetPath() has been called: avoid _PyPathConfig_Calculate() */
}
done:
PyMem_SetAllocator(PYMEM_DOMAIN_RAW, &old_alloc);
return status;
}
static PyStatus
config_calculate_pathconfig(PyConfig *config)
{
_PyPathConfig pathconfig = _PyPathConfig_INIT;
PyStatus status;
status = pathconfig_calculate(&pathconfig, config);
if (_PyStatus_EXCEPTION(status)) {
goto done;
}
if (!config->module_search_paths_set) {
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) { \
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)
{
/* 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_calculate_pathconfig(config);
if (_PyStatus_EXCEPTION(status)) {
return status;
}
}
if (config->base_prefix == NULL) {
if (copy_wstr(&config->base_prefix, config->prefix) < 0) {
return _PyStatus_NO_MEMORY();
}
}
if (config->base_exec_prefix == NULL) {
if (copy_wstr(&config->base_exec_prefix,
config->exec_prefix) < 0) {
return _PyStatus_NO_MEMORY();
}
}
if (config->base_executable == NULL) {
if (copy_wstr(&config->base_executable,
config->executable) < 0) {
return _PyStatus_NO_MEMORY();
}
}
return _PyStatus_OK();
}
static PyStatus
pathconfig_global_read(_PyPathConfig *pathconfig)
{
PyStatus status;
PyConfig config;
status = _PyConfig_InitCompatConfig(&config);
if (_PyStatus_EXCEPTION(status)) {
goto done;
}
/* Call _PyConfig_InitPathConfig() */
status = PyConfig_Read(&config);
if (_PyStatus_EXCEPTION(status)) {
goto done;
}
status = pathconfig_set_from_config(pathconfig, &config);
done:
PyConfig_Clear(&config);
return status;
}
static void
pathconfig_global_init(void)
{
PyStatus status;
#ifdef MS_WINDOWS
status = _PyPathConfig_InitDLLPath();
if (_PyStatus_EXCEPTION(status)) {
Py_ExitStatusException(status);
}
#endif
if (_Py_path_config.module_search_path == NULL) {
status = pathconfig_global_read(&_Py_path_config);
if (_PyStatus_EXCEPTION(status)) {
Py_ExitStatusException(status);
}
}
else {
/* Global configuration already initialized */
}
assert(_Py_path_config.program_full_path != NULL);
assert(_Py_path_config.prefix != NULL);
assert(_Py_path_config.exec_prefix != NULL);
assert(_Py_path_config.module_search_path != NULL);
assert(_Py_path_config.program_name != NULL);
/* home can be NULL */
#ifdef MS_WINDOWS
assert(_Py_path_config.base_executable != NULL);
#endif
}
/* External interface */
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);
/* Getting the program full path calls pathconfig_global_init() */
wchar_t *program_full_path = _PyMem_RawWcsdup(Py_GetProgramFullPath());
PyMem_RawFree(_Py_path_config.program_full_path);
PyMem_RawFree(_Py_path_config.prefix);
PyMem_RawFree(_Py_path_config.exec_prefix);
PyMem_RawFree(_Py_path_config.module_search_path);
_Py_path_config.program_full_path = program_full_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.program_full_path == NULL
|| _Py_path_config.prefix == NULL
|| _Py_path_config.exec_prefix == NULL
|| _Py_path_config.module_search_path == NULL)
{
Py_FatalError("Py_SetPath() failed: out of memory");
}
}
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) {
Py_FatalError("Py_SetPythonHome() failed: out of memory");
}
}
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) {
Py_FatalError("Py_SetProgramName() failed: out of memory");
}
}
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) {
Py_FatalError("_Py_SetProgramFullPath() failed: out of memory");
}
}
wchar_t *
Py_GetPath(void)
{
pathconfig_global_init();
return _Py_path_config.module_search_path;
}
wchar_t *
Py_GetPrefix(void)
{
pathconfig_global_init();
return _Py_path_config.prefix;
}
wchar_t *
Py_GetExecPrefix(void)
{
pathconfig_global_init();
return _Py_path_config.exec_prefix;
}
wchar_t *
Py_GetProgramFullPath(void)
{
pathconfig_global_init();
return _Py_path_config.program_full_path;
}
wchar_t*
Py_GetPythonHome(void)
{
pathconfig_global_init();
return _Py_path_config.home;
}
wchar_t *
Py_GetProgramName(void)
{
pathconfig_global_init();
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;
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 */
wchar_t path0copy[2 * MAXPATHLEN + 1];
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 the provided buffer. */
int
_Py_FindEnvConfigValue(FILE *env_file, const wchar_t *key,
wchar_t *value, size_t value_size)
{
int result = 0; /* meaning not found */
char buffer[MAXPATHLEN * 2 + 1]; /* allow extra for key, '=', etc. */
buffer[Py_ARRAY_LENGTH(buffer)-1] = '\0';
fseek(env_file, 0, SEEK_SET);
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) {
wcsncpy(value, tok, value_size - 1);
value[value_size - 1] = L'\0';
result = 1;
PyMem_RawFree(tmpbuffer);
break;
}
}
}
PyMem_RawFree(tmpbuffer);
}
}
return result;
}
#ifdef __cplusplus
}
#endif
Reference in a new issue View git blame Copy permalink