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1086 lines (952 loc) · 32.8 KB
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/* Return the initial module search path. */
#include "Python.h"
#include "osdefs.h"
#include <sys/types.h>
#include <string.h>
#ifdef __APPLE__
# include <mach-o/dyld.h>
#endif
/* Search in some common locations for the associated Python libraries.
*
* Two directories must be found, the platform independent directory
* (prefix), containing the common .py and .pyc files, and the platform
* dependent directory (exec_prefix), containing the shared library
* modules. Note that prefix and exec_prefix can be the same directory,
* but for some installations, they are different.
*
* Py_GetPath() carries out separate searches for prefix and exec_prefix.
* Each search tries a number of different locations until a ``landmark''
* file or directory is found. If no prefix or exec_prefix is found, a
* warning message is issued and the preprocessor defined PREFIX and
* EXEC_PREFIX are used (even though they will not work); python carries on
* as best as is possible, but most imports will fail.
*
* Before any searches are done, the location of the executable is
* determined. If argv[0] has one or more slashes in it, it is used
* unchanged. Otherwise, it must have been invoked from the shell's path,
* so we search $PATH for the named executable and use that. If the
* executable was not found on $PATH (or there was no $PATH environment
* variable), the original argv[0] string is used.
*
* Next, the executable location is examined to see if it is a symbolic
* link. If so, the link is chased (correctly interpreting a relative
* pathname if one is found) and the directory of the link target is used.
*
* Finally, argv0_path is set to the directory containing the executable
* (i.e. the last component is stripped).
*
* With argv0_path in hand, we perform a number of steps. The same steps
* are performed for prefix and for exec_prefix, but with a different
* landmark.
*
* Step 1. Are we running python out of the build directory? This is
* checked by looking for a different kind of landmark relative to
* argv0_path. For prefix, the landmark's path is derived from the VPATH
* preprocessor variable (taking into account that its value is almost, but
* not quite, what we need). For exec_prefix, the landmark is
* pybuilddir.txt. If the landmark is found, we're done.
*
* For the remaining steps, the prefix landmark will always be
* lib/python$VERSION/os.py and the exec_prefix will always be
* lib/python$VERSION/lib-dynload, where $VERSION is Python's version
* number as supplied by the Makefile. Note that this means that no more
* build directory checking is performed; if the first step did not find
* the landmarks, the assumption is that python is running from an
* installed setup.
*
* Step 2. See if the $PYTHONHOME environment variable points to the
* installed location of the Python libraries. If $PYTHONHOME is set, then
* it points to prefix and exec_prefix. $PYTHONHOME can be a single
* directory, which is used for both, or the prefix and exec_prefix
* directories separated by a colon.
*
* Step 3. Try to find prefix and exec_prefix relative to argv0_path,
* backtracking up the path until it is exhausted. This is the most common
* step to succeed. Note that if prefix and exec_prefix are different,
* exec_prefix is more likely to be found; however if exec_prefix is a
* subdirectory of prefix, both will be found.
*
* Step 4. Search the directories pointed to by the preprocessor variables
* PREFIX and EXEC_PREFIX. These are supplied by the Makefile but can be
* passed in as options to the configure script.
*
* That's it!
*
* Well, almost. Once we have determined prefix and exec_prefix, the
* preprocessor variable PYTHONPATH is used to construct a path. Each
* relative path on PYTHONPATH is prefixed with prefix. Then the directory
* containing the shared library modules is appended. The environment
* variable $PYTHONPATH is inserted in front of it all. Finally, the
* prefix and exec_prefix globals are tweaked so they reflect the values
* expected by other code, by stripping the "lib/python$VERSION/..." stuff
* off. If either points to the build directory, the globals are reset to
* the corresponding preprocessor variables (so sys.prefix will reflect the
* installation location, even though sys.path points into the build
* directory). This seems to make more sense given that currently the only
* known use of sys.prefix and sys.exec_prefix is for the ILU installation
* process to find the installed Python tree.
*
* An embedding application can use Py_SetPath() to override all of
* these authomatic path computations.
*
* NOTE: Windows MSVC builds use PC/getpathp.c instead!
*/
#ifdef __cplusplus
extern "C" {
#endif
#if !defined(PREFIX) || !defined(EXEC_PREFIX) || !defined(VERSION) || !defined(VPATH)
#error "PREFIX, EXEC_PREFIX, VERSION, and VPATH must be constant defined"
#endif
#ifndef LANDMARK
#define LANDMARK L"os.py"
#endif
typedef struct {
wchar_t prefix[MAXPATHLEN+1];
wchar_t exec_prefix[MAXPATHLEN+1];
wchar_t program_name[MAXPATHLEN+1];
wchar_t *module_search_path;
} PyPathConfig;
typedef struct {
wchar_t *path_env; /* PATH environment variable */
wchar_t *home; /* PYTHONHOME environment variable */
wchar_t *module_search_path_env; /* PYTHONPATH environment variable */
wchar_t *program_name; /* Program name */
wchar_t *pythonpath; /* PYTHONPATH define */
wchar_t *prefix; /* PREFIX define */
wchar_t *exec_prefix; /* EXEC_PREFIX define */
wchar_t *lib_python; /* "lib/pythonX.Y" */
wchar_t argv0_path[MAXPATHLEN+1];
wchar_t zip_path[MAXPATHLEN+1]; /* ".../lib/pythonXY.zip" */
int prefix_found; /* found platform independent libraries? */
int exec_prefix_found; /* found the platform dependent libraries? */
} PyCalculatePath;
static const wchar_t delimiter[2] = {DELIM, '\0'};
static const wchar_t separator[2] = {SEP, '\0'};
static PyPathConfig path_config = {.module_search_path = NULL};
/* Get file status. Encode the path to the locale encoding. */
static int
_Py_wstat(const wchar_t* path, struct stat *buf)
{
int err;
char *fname;
fname = Py_EncodeLocale(path, NULL);
if (fname == NULL) {
errno = EINVAL;
return -1;
}
err = stat(fname, buf);
PyMem_Free(fname);
return err;
}
static void
reduce(wchar_t *dir)
{
size_t i = wcslen(dir);
while (i > 0 && dir[i] != SEP)
--i;
dir[i] = '\0';
}
static int
isfile(wchar_t *filename) /* Is file, not directory */
{
struct stat buf;
if (_Py_wstat(filename, &buf) != 0) {
return 0;
}
if (!S_ISREG(buf.st_mode)) {
return 0;
}
return 1;
}
static int
ismodule(wchar_t *filename) /* Is module -- check for .pyc too */
{
if (isfile(filename)) {
return 1;
}
/* Check for the compiled version of prefix. */
if (wcslen(filename) < MAXPATHLEN) {
wcscat(filename, L"c");
if (isfile(filename)) {
return 1;
}
}
return 0;
}
/* Is executable file */
static int
isxfile(wchar_t *filename)
{
struct stat buf;
if (_Py_wstat(filename, &buf) != 0) {
return 0;
}
if (!S_ISREG(buf.st_mode)) {
return 0;
}
if ((buf.st_mode & 0111) == 0) {
return 0;
}
return 1;
}
/* Is directory */
static int
isdir(wchar_t *filename)
{
struct stat buf;
if (_Py_wstat(filename, &buf) != 0) {
return 0;
}
if (!S_ISDIR(buf.st_mode)) {
return 0;
}
return 1;
}
/* Add a path component, by appending stuff to buffer.
buffer must have at least MAXPATHLEN + 1 bytes allocated, and contain a
NUL-terminated string with no more than MAXPATHLEN characters (not counting
the trailing NUL). It's a fatal error if it contains a string longer than
that (callers must be careful!). If these requirements are met, it's
guaranteed that buffer will still be a NUL-terminated string with no more
than MAXPATHLEN characters at exit. If stuff is too long, only as much of
stuff as fits will be appended.
*/
static void
joinpath(wchar_t *buffer, wchar_t *stuff)
{
size_t n, k;
if (stuff[0] == SEP) {
n = 0;
}
else {
n = wcslen(buffer);
if (n > 0 && buffer[n-1] != SEP && n < MAXPATHLEN) {
buffer[n++] = SEP;
}
}
if (n > MAXPATHLEN) {
Py_FatalError("buffer overflow in getpath.c's joinpath()");
}
k = wcslen(stuff);
if (n + k > MAXPATHLEN) {
k = MAXPATHLEN - n;
}
wcsncpy(buffer+n, stuff, k);
buffer[n+k] = '\0';
}
/* copy_absolute requires that path be allocated at least
MAXPATHLEN + 1 bytes and that p be no more than MAXPATHLEN bytes. */
static void
copy_absolute(wchar_t *path, wchar_t *p, size_t pathlen)
{
if (p[0] == SEP) {
wcscpy(path, p);
}
else {
if (!_Py_wgetcwd(path, pathlen)) {
/* unable to get the current directory */
wcscpy(path, p);
return;
}
if (p[0] == '.' && p[1] == SEP) {
p += 2;
}
joinpath(path, p);
}
}
/* absolutize() requires that path be allocated at least MAXPATHLEN+1 bytes. */
static void
absolutize(wchar_t *path)
{
wchar_t buffer[MAXPATHLEN+1];
if (path[0] == SEP) {
return;
}
copy_absolute(buffer, path, MAXPATHLEN+1);
wcscpy(path, buffer);
}
/* search for a prefix value in an environment file. If found, copy it
to the provided buffer, which is expected to be no more than MAXPATHLEN
bytes long.
*/
static int
find_env_config_value(FILE * env_file, const wchar_t * key, wchar_t * value)
{
int result = 0; /* meaning not found */
char buffer[MAXPATHLEN*2+1]; /* allow extra for key, '=', etc. */
fseek(env_file, 0, SEEK_SET);
while (!feof(env_file)) {
char * p = fgets(buffer, MAXPATHLEN*2, env_file);
wchar_t tmpbuffer[MAXPATHLEN*2+1];
PyObject * decoded;
int n;
if (p == NULL) {
break;
}
n = strlen(p);
if (p[n - 1] != '\n') {
/* line has overflowed - bail */
break;
}
if (p[0] == '#') {
/* Comment - skip */
continue;
}
decoded = PyUnicode_DecodeUTF8(buffer, n, "surrogateescape");
if (decoded != NULL) {
Py_ssize_t k;
wchar_t * state;
k = PyUnicode_AsWideChar(decoded,
tmpbuffer, MAXPATHLEN * 2);
Py_DECREF(decoded);
if (k >= 0) {
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, MAXPATHLEN);
result = 1;
break;
}
}
}
}
}
}
return result;
}
/* search_for_prefix requires that argv0_path be no more than MAXPATHLEN
bytes long.
*/
static int
search_for_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
size_t n;
wchar_t *vpath;
/* If PYTHONHOME is set, we believe it unconditionally */
if (calculate->home) {
wcsncpy(config->prefix, calculate->home, MAXPATHLEN);
config->prefix[MAXPATHLEN] = L'\0';
wchar_t *delim = wcschr(config->prefix, DELIM);
if (delim) {
*delim = L'\0';
}
joinpath(config->prefix, calculate->lib_python);
joinpath(config->prefix, LANDMARK);
return 1;
}
/* Check to see if argv[0] is in the build directory */
wcsncpy(config->prefix, calculate->argv0_path, MAXPATHLEN);
config->prefix[MAXPATHLEN] = L'\0';
joinpath(config->prefix, L"Modules/Setup");
if (isfile(config->prefix)) {
/* Check VPATH to see if argv0_path is in the build directory. */
vpath = Py_DecodeLocale(VPATH, NULL);
if (vpath != NULL) {
wcsncpy(config->prefix, calculate->argv0_path, MAXPATHLEN);
config->prefix[MAXPATHLEN] = L'\0';
joinpath(config->prefix, vpath);
PyMem_RawFree(vpath);
joinpath(config->prefix, L"Lib");
joinpath(config->prefix, LANDMARK);
if (ismodule(config->prefix)) {
return -1;
}
}
}
/* Search from argv0_path, until root is found */
copy_absolute(config->prefix, calculate->argv0_path, MAXPATHLEN+1);
do {
n = wcslen(config->prefix);
joinpath(config->prefix, calculate->lib_python);
joinpath(config->prefix, LANDMARK);
if (ismodule(config->prefix)) {
return 1;
}
config->prefix[n] = L'\0';
reduce(config->prefix);
} while (config->prefix[0]);
/* Look at configure's PREFIX */
wcsncpy(config->prefix, calculate->prefix, MAXPATHLEN);
config->prefix[MAXPATHLEN] = L'\0';
joinpath(config->prefix, calculate->lib_python);
joinpath(config->prefix, LANDMARK);
if (ismodule(config->prefix)) {
return 1;
}
/* Fail */
return 0;
}
static void
calculate_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
calculate->prefix_found = search_for_prefix(calculate, config);
if (!calculate->prefix_found) {
if (!Py_FrozenFlag) {
fprintf(stderr,
"Could not find platform independent libraries <prefix>\n");
}
wcsncpy(config->prefix, calculate->prefix, MAXPATHLEN);
joinpath(config->prefix, calculate->lib_python);
}
else {
reduce(config->prefix);
}
}
static void
calculate_reduce_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
/* Reduce prefix and exec_prefix to their essence,
* e.g. /usr/local/lib/python1.5 is reduced to /usr/local.
* If we're loading relative to the build directory,
* return the compiled-in defaults instead.
*/
if (calculate->prefix_found > 0) {
reduce(config->prefix);
reduce(config->prefix);
/* The prefix is the root directory, but reduce() chopped
* off the "/". */
if (!config->prefix[0]) {
wcscpy(config->prefix, separator);
}
}
else {
wcsncpy(config->prefix, calculate->prefix, MAXPATHLEN);
}
}
/* search_for_exec_prefix requires that argv0_path be no more than
MAXPATHLEN bytes long.
*/
static int
search_for_exec_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
size_t n;
/* If PYTHONHOME is set, we believe it unconditionally */
if (calculate->home) {
wchar_t *delim = wcschr(calculate->home, DELIM);
if (delim) {
wcsncpy(config->exec_prefix, delim+1, MAXPATHLEN);
}
else {
wcsncpy(config->exec_prefix, calculate->home, MAXPATHLEN);
}
config->exec_prefix[MAXPATHLEN] = L'\0';
joinpath(config->exec_prefix, calculate->lib_python);
joinpath(config->exec_prefix, L"lib-dynload");
return 1;
}
/* Check to see if argv[0] is in the build directory. "pybuilddir.txt"
is written by setup.py and contains the relative path to the location
of shared library modules. */
wcsncpy(config->exec_prefix, calculate->argv0_path, MAXPATHLEN);
config->exec_prefix[MAXPATHLEN] = L'\0';
joinpath(config->exec_prefix, L"pybuilddir.txt");
if (isfile(config->exec_prefix)) {
FILE *f = _Py_wfopen(config->exec_prefix, L"rb");
if (f == NULL) {
errno = 0;
}
else {
char buf[MAXPATHLEN+1];
PyObject *decoded;
wchar_t rel_builddir_path[MAXPATHLEN+1];
n = fread(buf, 1, MAXPATHLEN, f);
buf[n] = '\0';
fclose(f);
decoded = PyUnicode_DecodeUTF8(buf, n, "surrogateescape");
if (decoded != NULL) {
Py_ssize_t k;
k = PyUnicode_AsWideChar(decoded,
rel_builddir_path, MAXPATHLEN);
Py_DECREF(decoded);
if (k >= 0) {
rel_builddir_path[k] = L'\0';
wcsncpy(config->exec_prefix, calculate->argv0_path, MAXPATHLEN);
config->exec_prefix[MAXPATHLEN] = L'\0';
joinpath(config->exec_prefix, rel_builddir_path);
return -1;
}
}
}
}
/* Search from argv0_path, until root is found */
copy_absolute(config->exec_prefix, calculate->argv0_path, MAXPATHLEN+1);
do {
n = wcslen(config->exec_prefix);
joinpath(config->exec_prefix, calculate->lib_python);
joinpath(config->exec_prefix, L"lib-dynload");
if (isdir(config->exec_prefix)) {
return 1;
}
config->exec_prefix[n] = L'\0';
reduce(config->exec_prefix);
} while (config->exec_prefix[0]);
/* Look at configure's EXEC_PREFIX */
wcsncpy(config->exec_prefix, calculate->exec_prefix, MAXPATHLEN);
config->exec_prefix[MAXPATHLEN] = L'\0';
joinpath(config->exec_prefix, calculate->lib_python);
joinpath(config->exec_prefix, L"lib-dynload");
if (isdir(config->exec_prefix)) {
return 1;
}
/* Fail */
return 0;
}
static void
calculate_exec_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
calculate->exec_prefix_found = search_for_exec_prefix(calculate, config);
if (!calculate->exec_prefix_found) {
if (!Py_FrozenFlag) {
fprintf(stderr,
"Could not find platform dependent libraries <exec_prefix>\n");
}
wcsncpy(config->exec_prefix, calculate->exec_prefix, MAXPATHLEN);
joinpath(config->exec_prefix, L"lib/lib-dynload");
}
/* If we found EXEC_PREFIX do *not* reduce it! (Yet.) */
}
static void
calculate_reduce_exec_prefix(PyCalculatePath *calculate, PyPathConfig *config)
{
if (calculate->exec_prefix_found > 0) {
reduce(config->exec_prefix);
reduce(config->exec_prefix);
reduce(config->exec_prefix);
if (!config->exec_prefix[0]) {
wcscpy(config->exec_prefix, separator);
}
}
else {
wcsncpy(config->exec_prefix, calculate->exec_prefix, MAXPATHLEN);
}
}
static void
calculate_progpath(PyCalculatePath *calculate, PyPathConfig *config)
{
#ifdef __APPLE__
#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_4
uint32_t nsexeclength = MAXPATHLEN;
#else
unsigned long nsexeclength = MAXPATHLEN;
#endif
char execpath[MAXPATHLEN+1];
#endif
/* If there is no slash in the argv0 path, then we have to
* assume python is on the user's $PATH, since there's no
* other way to find a directory to start the search from. If
* $PATH isn't exported, you lose.
*/
if (wcschr(calculate->program_name, SEP)) {
wcsncpy(config->program_name, calculate->program_name, MAXPATHLEN);
}
#ifdef __APPLE__
/* On Mac OS X, if a script uses an interpreter of the form
* "#!/opt/python2.3/bin/python", the kernel only passes "python"
* as argv[0], which falls through to the $PATH search below.
* If /opt/python2.3/bin isn't in your path, or is near the end,
* this algorithm may incorrectly find /usr/bin/python. To work
* around this, we can use _NSGetExecutablePath to get a better
* hint of what the intended interpreter was, although this
* will fail if a relative path was used. but in that case,
* absolutize() should help us out below
*/
else if(0 == _NSGetExecutablePath(execpath, &nsexeclength) &&
execpath[0] == SEP)
{
size_t r = mbstowcs(config->program_name, execpath, MAXPATHLEN+1);
if (r == (size_t)-1 || r > MAXPATHLEN) {
/* Could not convert execpath, or it's too long. */
config->program_name[0] = '\0';
}
}
#endif /* __APPLE__ */
else if (calculate->path_env) {
wchar_t *path = calculate->path_env;
while (1) {
wchar_t *delim = wcschr(path, DELIM);
if (delim) {
size_t len = delim - path;
if (len > MAXPATHLEN) {
len = MAXPATHLEN;
}
wcsncpy(config->program_name, path, len);
*(config->program_name + len) = '\0';
}
else {
wcsncpy(config->program_name, path, MAXPATHLEN);
}
joinpath(config->program_name, calculate->program_name);
if (isxfile(config->program_name)) {
break;
}
if (!delim) {
config->program_name[0] = L'\0';
break;
}
path = delim + 1;
}
}
else {
config->program_name[0] = '\0';
}
if (config->program_name[0] != SEP && config->program_name[0] != '\0') {
absolutize(config->program_name);
}
}
static void
calculate_argv0_path(PyCalculatePath *calculate, PyPathConfig *config)
{
wcsncpy(calculate->argv0_path, config->program_name, MAXPATHLEN);
calculate->argv0_path[MAXPATHLEN] = '\0';
#ifdef WITH_NEXT_FRAMEWORK
NSModule pythonModule;
/* On Mac OS X we have a special case if we're running from a framework.
** This is because the python home should be set relative to the library,
** which is in the framework, not relative to the executable, which may
** be outside of the framework. Except when we're in the build directory...
*/
pythonModule = NSModuleForSymbol(NSLookupAndBindSymbol("_Py_Initialize"));
/* Use dylib functions to find out where the framework was loaded from */
const char* modPath = NSLibraryNameForModule(pythonModule);
if (modPath != NULL) {
/* We're in a framework. */
/* See if we might be in the build directory. The framework in the
** build directory is incomplete, it only has the .dylib and a few
** needed symlinks, it doesn't have the Lib directories and such.
** If we're running with the framework from the build directory we must
** be running the interpreter in the build directory, so we use the
** build-directory-specific logic to find Lib and such.
*/
wchar_t* wbuf = Py_DecodeLocale(modPath, NULL);
if (wbuf == NULL) {
Py_FatalError("Cannot decode framework location");
}
wcsncpy(calculate->argv0_path, wbuf, MAXPATHLEN);
reduce(calculate->argv0_path);
joinpath(calculate->argv0_path, calculate->lib_python);
joinpath(calculate->argv0_path, LANDMARK);
if (!ismodule(calculate->argv0_path)) {
/* We are in the build directory so use the name of the
executable - we know that the absolute path is passed */
wcsncpy(calculate->argv0_path, config->program_name, MAXPATHLEN);
}
else {
/* Use the location of the library as the program_name */
wcsncpy(calculate->argv0_path, wbuf, MAXPATHLEN);
}
PyMem_RawFree(wbuf);
}
#endif
#if HAVE_READLINK
wchar_t tmpbuffer[MAXPATHLEN+1];
int linklen = _Py_wreadlink(config->program_name, tmpbuffer, MAXPATHLEN);
while (linklen != -1) {
if (tmpbuffer[0] == SEP) {
/* tmpbuffer should never be longer than MAXPATHLEN,
but extra check does not hurt */
wcsncpy(calculate->argv0_path, tmpbuffer, MAXPATHLEN);
}
else {
/* Interpret relative to program_name */
reduce(calculate->argv0_path);
joinpath(calculate->argv0_path, tmpbuffer);
}
linklen = _Py_wreadlink(calculate->argv0_path, tmpbuffer, MAXPATHLEN);
}
#endif /* HAVE_READLINK */
reduce(calculate->argv0_path);
/* At this point, argv0_path is guaranteed to be less than
MAXPATHLEN bytes long. */
}
/* Search for an "pyvenv.cfg" environment configuration file, first in the
executable's directory and then in the parent directory.
If found, open it for use when searching for prefixes.
*/
static void
calculate_read_pyenv(PyCalculatePath *calculate)
{
wchar_t tmpbuffer[MAXPATHLEN+1];
wchar_t *env_cfg = L"pyvenv.cfg";
FILE *env_file;
wcscpy(tmpbuffer, calculate->argv0_path);
joinpath(tmpbuffer, env_cfg);
env_file = _Py_wfopen(tmpbuffer, L"r");
if (env_file == NULL) {
errno = 0;
reduce(tmpbuffer);
reduce(tmpbuffer);
joinpath(tmpbuffer, env_cfg);
env_file = _Py_wfopen(tmpbuffer, L"r");
if (env_file == NULL) {
errno = 0;
}
}
if (env_file == NULL) {
return;
}
/* Look for a 'home' variable and set argv0_path to it, if found */
if (find_env_config_value(env_file, L"home", tmpbuffer)) {
wcscpy(calculate->argv0_path, tmpbuffer);
}
fclose(env_file);
}
static void
calculate_zip_path(PyCalculatePath *calculate, PyPathConfig *config)
{
wcsncpy(calculate->zip_path, config->prefix, MAXPATHLEN);
calculate->zip_path[MAXPATHLEN] = L'\0';
if (calculate->prefix_found > 0) {
/* Use the reduced prefix returned by Py_GetPrefix() */
reduce(calculate->zip_path);
reduce(calculate->zip_path);
}
else {
wcsncpy(calculate->zip_path, calculate->prefix, MAXPATHLEN);
}
joinpath(calculate->zip_path, L"lib/python00.zip");
/* Replace "00" with version */
size_t bufsz = wcslen(calculate->zip_path);
calculate->zip_path[bufsz - 6] = VERSION[0];
calculate->zip_path[bufsz - 5] = VERSION[2];
}
static wchar_t *
calculate_module_search_path(PyCalculatePath *calculate, PyPathConfig *config)
{
/* Calculate size of return buffer */
size_t bufsz = 0;
if (calculate->module_search_path_env != NULL) {
bufsz += wcslen(calculate->module_search_path_env) + 1;
}
wchar_t *defpath = calculate->pythonpath;
size_t prefixsz = wcslen(config->prefix) + 1;
while (1) {
wchar_t *delim = wcschr(defpath, DELIM);
if (defpath[0] != SEP) {
/* Paths are relative to prefix */
bufsz += prefixsz;
}
if (delim) {
bufsz += delim - defpath + 1;
}
else {
bufsz += wcslen(defpath) + 1;
break;
}
defpath = delim + 1;
}
bufsz += wcslen(calculate->zip_path) + 1;
bufsz += wcslen(config->exec_prefix) + 1;
/* Allocate the buffer */
wchar_t *buf = PyMem_RawMalloc(bufsz * sizeof(wchar_t));
if (buf == NULL) {
Py_FatalError(
"Not enough memory for dynamic PYTHONPATH");
}
buf[0] = '\0';
/* Run-time value of $PYTHONPATH goes first */
if (calculate->module_search_path_env) {
wcscpy(buf, calculate->module_search_path_env);
wcscat(buf, delimiter);
}
/* Next is the default zip path */
wcscat(buf, calculate->zip_path);
wcscat(buf, delimiter);
/* Next goes merge of compile-time $PYTHONPATH with
* dynamically located prefix.
*/
defpath = calculate->pythonpath;
while (1) {
wchar_t *delim = wcschr(defpath, DELIM);
if (defpath[0] != SEP) {
wcscat(buf, config->prefix);
if (prefixsz >= 2 && config->prefix[prefixsz - 2] != SEP &&
defpath[0] != (delim ? DELIM : L'\0'))
{
/* not empty */
wcscat(buf, separator);
}
}
if (delim) {
size_t len = delim - defpath + 1;
size_t end = wcslen(buf) + len;
wcsncat(buf, defpath, len);
*(buf + end) = '\0';
}
else {
wcscat(buf, defpath);
break;
}
defpath = delim + 1;
}
wcscat(buf, delimiter);
/* Finally, on goes the directory for dynamic-load modules */
wcscat(buf, config->exec_prefix);
return buf;
}
#define DECODE_LOCALE_ERR(NAME, LEN) \
((LEN) == (size_t)-2) \
? _Py_INIT_USER_ERR("failed to decode " #NAME) \
: _Py_INIT_NO_MEMORY()
static _PyInitError
calculate_init(PyCalculatePath *calculate,
const _PyMainInterpreterConfig *main_config)
{
calculate->home = main_config->home;
calculate->module_search_path_env = main_config->module_search_path_env;
calculate->program_name = main_config->program_name;
size_t len;
char *path = getenv("PATH");
if (path) {
calculate->path_env = Py_DecodeLocale(path, &len);
if (!calculate->path_env) {
return DECODE_LOCALE_ERR("PATH environment variable", len);
}
}
calculate->pythonpath = Py_DecodeLocale(PYTHONPATH, &len);
if (!calculate->pythonpath) {
return DECODE_LOCALE_ERR("PYTHONPATH define", len);
}
calculate->prefix = Py_DecodeLocale(PREFIX, &len);
if (!calculate->prefix) {
return DECODE_LOCALE_ERR("PREFIX define", len);
}
calculate->exec_prefix = Py_DecodeLocale(EXEC_PREFIX, &len);
if (!calculate->prefix) {
return DECODE_LOCALE_ERR("EXEC_PREFIX define", len);
}
calculate->lib_python = Py_DecodeLocale("lib/python" VERSION, &len);
if (!calculate->lib_python) {
return DECODE_LOCALE_ERR("EXEC_PREFIX define", len);
}
return _Py_INIT_OK();
}
static void
calculate_free(PyCalculatePath *calculate)
{
PyMem_RawFree(calculate->pythonpath);
PyMem_RawFree(calculate->prefix);
PyMem_RawFree(calculate->exec_prefix);
PyMem_RawFree(calculate->lib_python);
PyMem_RawFree(calculate->path_env);
}
static void
calculate_path_impl(PyCalculatePath *calculate, PyPathConfig *config)
{
calculate_progpath(calculate, config);
calculate_argv0_path(calculate, config);
calculate_read_pyenv(calculate);
calculate_prefix(calculate, config);
calculate_zip_path(calculate, config);
calculate_exec_prefix(calculate, config);
if ((!calculate->prefix_found || !calculate->exec_prefix_found) &&
!Py_FrozenFlag)
{
fprintf(stderr,
"Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]\n");
}
config->module_search_path = calculate_module_search_path(calculate, config);
calculate_reduce_prefix(calculate, config);
calculate_reduce_exec_prefix(calculate, config);
}
static void
calculate_path(const _PyMainInterpreterConfig *main_config)
{
_PyInitError err;
PyCalculatePath calculate;
memset(&calculate, 0, sizeof(calculate));
_PyMainInterpreterConfig tmp_config;
int use_tmp = (main_config == NULL);
if (use_tmp) {
tmp_config = _PyMainInterpreterConfig_INIT;
err = _PyMainInterpreterConfig_ReadEnv(&tmp_config);
if (_Py_INIT_FAILED(err)) {
goto fatal_error;
}
main_config = &tmp_config;
}
err = calculate_init(&calculate, main_config);
if (_Py_INIT_FAILED(err)) {
goto fatal_error;
}
PyPathConfig new_path_config;
memset(&new_path_config, 0, sizeof(new_path_config));
calculate_path_impl(&calculate, &new_path_config);
path_config = new_path_config;
if (use_tmp) {
_PyMainInterpreterConfig_Clear(&tmp_config);
}
calculate_free(&calculate);
return;