bpo-32197: Try to fix a compiler error on OS X introduced in bpo-32030. (#4681)

* Revert "bpo-32030: _PyPathConfig_Init() sets home and program_name (#4673)"

This reverts commit af5a895073c24637c094772b27526b94a12ec897.

* Revert "bpo-32030: Fix config_get_program_name() on macOS (#4669)"

This reverts commit e23c06e2b03452c9aaf0dae52296c85e572f9bcd.

* Revert "bpo-32030: Add Python/pathconfig.c (#4668)"

This reverts commit 0ea395ae964c9cd0f499e2ef0d0030c971201220.

* Revert "bpo-32030: Don't call _PyPathConfig_Fini() in Py_FinalizeEx() (#4667)"

This reverts commit ebac19dad6263141d5db0a2c923efe049dba99d2.

* Revert "bpo-32030: Fix Py_GetPath(): init program_name (#4665)"

This reverts commit 9ac3d8882712c9675c3d2f9f84af6b5729575cde.

1 files changed, 151 insertions, 46 deletions

diff --git a/Modules/getpath.c b/Modules/getpath.c
index fc2b544..9f5e8b3 100644
--- a/Modules/getpath.c
+++ b/Modules/getpath.c
@@ -117,7 +117,10 @@ extern "C" {
 
 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 */
@@ -132,6 +135,7 @@ typedef struct {
 
 static const wchar_t delimiter[2] = {DELIM, '\0'};
 static const wchar_t separator[2] = {SEP, '\0'};
+static _PyPathConfig _Py_path_config = _PyPathConfig_INIT;
 
 
 /* Get file status. Encode the path to the locale encoding. */
@@ -356,15 +360,14 @@ find_env_config_value(FILE * env_file, const wchar_t * key, wchar_t * value)
    bytes long.
 */
 static int
-search_for_prefix(const _PyMainInterpreterConfig *main_config,
-                  PyCalculatePath *calculate, wchar_t *prefix)
+search_for_prefix(PyCalculatePath *calculate, wchar_t *prefix)
 {
     size_t n;
     wchar_t *vpath;
 
     /* If PYTHONHOME is set, we believe it unconditionally */
-    if (main_config->home) {
-        wcsncpy(prefix, main_config->home, MAXPATHLEN);
+    if (calculate->home) {
+        wcsncpy(prefix, calculate->home, MAXPATHLEN);
         prefix[MAXPATHLEN] = L'\0';
         wchar_t *delim = wcschr(prefix, DELIM);
         if (delim) {
@@ -423,10 +426,9 @@ search_for_prefix(const _PyMainInterpreterConfig *main_config,
 
 
 static void
-calculate_prefix(const _PyMainInterpreterConfig *main_config,
-                 PyCalculatePath *calculate, wchar_t *prefix)
+calculate_prefix(PyCalculatePath *calculate, wchar_t *prefix)
 {
-    calculate->prefix_found = search_for_prefix(main_config, calculate, prefix);
+    calculate->prefix_found = search_for_prefix(calculate, prefix);
     if (!calculate->prefix_found) {
         if (!Py_FrozenFlag) {
             fprintf(stderr,
@@ -468,19 +470,18 @@ calculate_reduce_prefix(PyCalculatePath *calculate, wchar_t *prefix)
    MAXPATHLEN bytes long.
 */
 static int
-search_for_exec_prefix(const _PyMainInterpreterConfig *main_config,
-                       PyCalculatePath *calculate, wchar_t *exec_prefix)
+search_for_exec_prefix(PyCalculatePath *calculate, wchar_t *exec_prefix)
 {
     size_t n;
 
     /* If PYTHONHOME is set, we believe it unconditionally */
-    if (main_config->home) {
-        wchar_t *delim = wcschr(main_config->home, DELIM);
+    if (calculate->home) {
+        wchar_t *delim = wcschr(calculate->home, DELIM);
         if (delim) {
             wcsncpy(exec_prefix, delim+1, MAXPATHLEN);
         }
         else {
-            wcsncpy(exec_prefix, main_config->home, MAXPATHLEN);
+            wcsncpy(exec_prefix, calculate->home, MAXPATHLEN);
         }
         exec_prefix[MAXPATHLEN] = L'\0';
         joinpath(exec_prefix, calculate->lib_python);
@@ -551,12 +552,9 @@ search_for_exec_prefix(const _PyMainInterpreterConfig *main_config,
 
 
 static void
-calculate_exec_prefix(const _PyMainInterpreterConfig *main_config,
-                      PyCalculatePath *calculate, wchar_t *exec_prefix)
+calculate_exec_prefix(PyCalculatePath *calculate, wchar_t *exec_prefix)
 {
-    calculate->exec_prefix_found = search_for_exec_prefix(main_config,
-                                                          calculate,
-                                                          exec_prefix);
+    calculate->exec_prefix_found = search_for_exec_prefix(calculate, exec_prefix);
     if (!calculate->exec_prefix_found) {
         if (!Py_FrozenFlag) {
             fprintf(stderr,
@@ -587,8 +585,7 @@ calculate_reduce_exec_prefix(PyCalculatePath *calculate, wchar_t *exec_prefix)
 
 
 static _PyInitError
-calculate_program_full_path(const _PyMainInterpreterConfig *main_config,
-                            PyCalculatePath *calculate, _PyPathConfig *config)
+calculate_program_full_path(PyCalculatePath *calculate, _PyPathConfig *config)
 {
     wchar_t program_full_path[MAXPATHLEN+1];
     memset(program_full_path, 0, sizeof(program_full_path));
@@ -607,8 +604,8 @@ calculate_program_full_path(const _PyMainInterpreterConfig *main_config,
      * other way to find a directory to start the search from.  If
      * $PATH isn't exported, you lose.
      */
-    if (wcschr(main_config->program_name, SEP)) {
-        wcsncpy(program_full_path, main_config->program_name, MAXPATHLEN);
+    if (wcschr(calculate->program_name, SEP)) {
+        wcsncpy(program_full_path, calculate->program_name, MAXPATHLEN);
     }
 #ifdef __APPLE__
      /* On Mac OS X, if a script uses an interpreter of the form
@@ -624,13 +621,11 @@ calculate_program_full_path(const _PyMainInterpreterConfig *main_config,
     else if(0 == _NSGetExecutablePath(execpath, &nsexeclength) &&
             execpath[0] == SEP)
     {
-        size_t len;
-        wchar_t *path = Py_DecodeLocale(execpath, &len);
-        if (path == NULL) {
-            return DECODE_LOCALE_ERR("executable path", len);
+        size_t r = mbstowcs(program_full_path, execpath, MAXPATHLEN+1);
+        if (r == (size_t)-1 || r > MAXPATHLEN) {
+            /* Could not convert execpath, or it's too long. */
+            program_full_path[0] = '\0';
         }
-        wcsncpy(program_full_path, path, MAXPATHLEN);
-        PyMem_RawFree(path);
     }
 #endif /* __APPLE__ */
     else if (calculate->path_env) {
@@ -650,7 +645,7 @@ calculate_program_full_path(const _PyMainInterpreterConfig *main_config,
                 wcsncpy(program_full_path, path, MAXPATHLEN);
             }
 
-            joinpath(program_full_path, main_config->program_name);
+            joinpath(program_full_path, calculate->program_name);
             if (isxfile(program_full_path)) {
                 break;
             }
@@ -815,15 +810,14 @@ calculate_zip_path(PyCalculatePath *calculate, const wchar_t *prefix)
 
 
 static _PyInitError
-calculate_module_search_path(const _PyMainInterpreterConfig *main_config,
-                             PyCalculatePath *calculate,
+calculate_module_search_path(PyCalculatePath *calculate,
                              const wchar_t *prefix, const wchar_t *exec_prefix,
                              _PyPathConfig *config)
 {
     /* Calculate size of return buffer */
     size_t bufsz = 0;
-    if (main_config->module_search_path_env != NULL) {
-        bufsz += wcslen(main_config->module_search_path_env) + 1;
+    if (calculate->module_search_path_env != NULL) {
+        bufsz += wcslen(calculate->module_search_path_env) + 1;
     }
 
     wchar_t *defpath = calculate->pythonpath;
@@ -857,8 +851,8 @@ calculate_module_search_path(const _PyMainInterpreterConfig *main_config,
     buf[0] = '\0';
 
     /* Run-time value of $PYTHONPATH goes first */
-    if (main_config->module_search_path_env) {
-        wcscpy(buf, main_config->module_search_path_env);
+    if (calculate->module_search_path_env) {
+        wcscpy(buf, calculate->module_search_path_env);
         wcscat(buf, delimiter);
     }
 
@@ -909,6 +903,10 @@ 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) {
@@ -950,12 +948,9 @@ calculate_free(PyCalculatePath *calculate)
 
 
 static _PyInitError
-calculate_path_impl(const _PyMainInterpreterConfig *main_config,
-                    PyCalculatePath *calculate, _PyPathConfig *config)
+calculate_path_impl(PyCalculatePath *calculate, _PyPathConfig *config)
 {
-    _PyInitError err;
-
-    err = calculate_program_full_path(main_config, calculate, config);
+    _PyInitError err = calculate_program_full_path(calculate, config);
     if (_Py_INIT_FAILED(err)) {
         return err;
     }
@@ -969,13 +964,13 @@ calculate_path_impl(const _PyMainInterpreterConfig *main_config,
 
     wchar_t prefix[MAXPATHLEN+1];
     memset(prefix, 0, sizeof(prefix));
-    calculate_prefix(main_config, calculate, prefix);
+    calculate_prefix(calculate, prefix);
 
     calculate_zip_path(calculate, prefix);
 
     wchar_t exec_prefix[MAXPATHLEN+1];
     memset(exec_prefix, 0, sizeof(exec_prefix));
-    calculate_exec_prefix(main_config, calculate, exec_prefix);
+    calculate_exec_prefix(calculate, exec_prefix);
 
     if ((!calculate->prefix_found || !calculate->exec_prefix_found) &&
         !Py_FrozenFlag)
@@ -984,8 +979,8 @@ calculate_path_impl(const _PyMainInterpreterConfig *main_config,
                 "Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]\n");
     }
 
-    err = calculate_module_search_path(main_config, calculate,
-                                       prefix, exec_prefix, config);
+    err = calculate_module_search_path(calculate, prefix, exec_prefix,
+                                       config);
     if (_Py_INIT_FAILED(err)) {
         return err;
     }
@@ -1008,10 +1003,33 @@ calculate_path_impl(const _PyMainInterpreterConfig *main_config,
 }
 
 
+static void
+pathconfig_clear(_PyPathConfig *config)
+{
+#define CLEAR(ATTR) \
+    do { \
+        PyMem_RawFree(ATTR); \
+        ATTR = NULL; \
+    } while (0)
+
+    CLEAR(config->prefix);
+    CLEAR(config->exec_prefix);
+    CLEAR(config->program_full_path);
+    CLEAR(config->module_search_path);
+#undef CLEAR
+}
+
+
+/* Initialize paths for Py_GetPath(), Py_GetPrefix(), Py_GetExecPrefix()
+   and Py_GetProgramFullPath() */
 _PyInitError
-_PyPathConfig_Calculate(_PyPathConfig *config,
-                        const _PyMainInterpreterConfig *main_config)
+_PyPathConfig_Init(const _PyMainInterpreterConfig *main_config)
 {
+    if (_Py_path_config.module_search_path) {
+        /* Already initialized */
+        return _Py_INIT_OK();
+    }
+
     PyCalculatePath calculate;
     memset(&calculate, 0, sizeof(calculate));
 
@@ -1020,11 +1038,16 @@ _PyPathConfig_Calculate(_PyPathConfig *config,
         goto done;
     }
 
-    err = calculate_path_impl(main_config, &calculate, config);
+    _PyPathConfig new_path_config;
+    memset(&new_path_config, 0, sizeof(new_path_config));
+
+    err = calculate_path_impl(&calculate, &new_path_config);
     if (_Py_INIT_FAILED(err)) {
+        pathconfig_clear(&new_path_config);
         goto done;
     }
 
+    _Py_path_config = new_path_config;
     err = _Py_INIT_OK();
 
 done:
@@ -1032,6 +1055,88 @@ done:
     return err;
 }
 
+
+static void
+pathconfig_global_init(void)
+{
+    if (_Py_path_config.module_search_path) {
+        /* Already initialized */
+        return;
+    }
+
+    _PyInitError err;
+    _PyMainInterpreterConfig config = _PyMainInterpreterConfig_INIT;
+
+    err = _PyMainInterpreterConfig_ReadEnv(&config);
+    if (!_Py_INIT_FAILED(err)) {
+        err = _PyPathConfig_Init(&config);
+    }
+    _PyMainInterpreterConfig_Clear(&config);
+
+    if (_Py_INIT_FAILED(err)) {
+        _Py_FatalInitError(err);
+    }
+}
+
+
+void
+_PyPathConfig_Fini(void)
+{
+    pathconfig_clear(&_Py_path_config);
+}
+
+
+/* External interface */
+void
+Py_SetPath(const wchar_t *path)
+{
+    if (path == NULL) {
+        pathconfig_clear(&_Py_path_config);
+        return;
+    }
+
+    _PyPathConfig new_config;
+    new_config.program_full_path = _PyMem_RawWcsdup(Py_GetProgramName());
+    new_config.exec_prefix = _PyMem_RawWcsdup(L"");
+    new_config.prefix = _PyMem_RawWcsdup(L"");
+    new_config.module_search_path = _PyMem_RawWcsdup(path);
+
+    pathconfig_clear(&_Py_path_config);
+    _Py_path_config = new_config;
+}
+
+
+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;
+}
+
 #ifdef __cplusplus
 }
 #endif