diff options
Diffstat (limited to 'Python/crossinterp.c')
| -rw-r--r-- | Python/crossinterp.c | 1938 |
1 files changed, 1284 insertions, 654 deletions
diff --git a/Python/crossinterp.c b/Python/crossinterp.c index 7d7e6551c3f..16a23f0351c 100644 --- a/Python/crossinterp.c +++ b/Python/crossinterp.c @@ -7,9 +7,13 @@ #include "pycore_ceval.h" // _Py_simple_func #include "pycore_crossinterp.h" // _PyXIData_t #include "pycore_function.h" // _PyFunction_VerifyStateless() +#include "pycore_global_strings.h" // _Py_ID() +#include "pycore_import.h" // _PyImport_SetModule() #include "pycore_initconfig.h" // _PyStatus_OK() #include "pycore_namespace.h" // _PyNamespace_New() #include "pycore_pythonrun.h" // _Py_SourceAsString() +#include "pycore_runtime.h" // _PyRuntime +#include "pycore_setobject.h" // _PySet_NextEntry() #include "pycore_typeobject.h" // _PyStaticType_InitBuiltin() @@ -21,6 +25,7 @@ _Py_GetMainfile(char *buffer, size_t maxlen) PyThreadState *tstate = _PyThreadState_GET(); PyObject *module = _Py_GetMainModule(tstate); if (_Py_CheckMainModule(module) < 0) { + Py_XDECREF(module); return -1; } Py_ssize_t size = _PyModule_GetFilenameUTF8(module, buffer, maxlen); @@ -30,27 +35,6 @@ _Py_GetMainfile(char *buffer, size_t maxlen) static PyObject * -import_get_module(PyThreadState *tstate, const char *modname) -{ - PyObject *module = NULL; - if (strcmp(modname, "__main__") == 0) { - module = _Py_GetMainModule(tstate); - if (_Py_CheckMainModule(module) < 0) { - assert(_PyErr_Occurred(tstate)); - return NULL; - } - } - else { - module = PyImport_ImportModule(modname); - if (module == NULL) { - return NULL; - } - } - return module; -} - - -static PyObject * runpy_run_path(const char *filename, const char *modname) { PyObject *run_path = PyImport_ImportModuleAttrString("runpy", "run_path"); @@ -69,97 +53,192 @@ runpy_run_path(const char *filename, const char *modname) } -static PyObject * -pyerr_get_message(PyObject *exc) +static void +set_exc_with_cause(PyObject *exctype, const char *msg) { - assert(!PyErr_Occurred()); - PyObject *args = PyException_GetArgs(exc); - if (args == NULL || args == Py_None || PyObject_Size(args) < 1) { - return NULL; - } - if (PyUnicode_Check(args)) { - return args; - } - PyObject *msg = PySequence_GetItem(args, 0); - Py_DECREF(args); - if (msg == NULL) { - PyErr_Clear(); - return NULL; - } - if (!PyUnicode_Check(msg)) { - Py_DECREF(msg); - return NULL; - } - return msg; + PyObject *cause = PyErr_GetRaisedException(); + PyErr_SetString(exctype, msg); + PyObject *exc = PyErr_GetRaisedException(); + PyException_SetCause(exc, cause); + PyErr_SetRaisedException(exc); } -#define MAX_MODNAME (255) -#define MAX_ATTRNAME (255) -struct attributeerror_info { - char modname[MAX_MODNAME+1]; - char attrname[MAX_ATTRNAME+1]; +/****************************/ +/* module duplication utils */ +/****************************/ + +struct sync_module_result { + PyObject *module; + PyObject *loaded; + PyObject *failed; +}; + +struct sync_module { + const char *filename; + char _filename[MAXPATHLEN+1]; + struct sync_module_result cached; }; +static void +sync_module_clear(struct sync_module *data) +{ + data->filename = NULL; + Py_CLEAR(data->cached.module); + Py_CLEAR(data->cached.loaded); + Py_CLEAR(data->cached.failed); +} + +static void +sync_module_capture_exc(PyThreadState *tstate, struct sync_module *data) +{ + assert(_PyErr_Occurred(tstate)); + PyObject *context = data->cached.failed; + PyObject *exc = _PyErr_GetRaisedException(tstate); + _PyErr_SetRaisedException(tstate, Py_NewRef(exc)); + if (context != NULL) { + PyException_SetContext(exc, context); + } + data->cached.failed = exc; +} + + static int -_parse_attributeerror(PyObject *exc, struct attributeerror_info *info) +ensure_isolated_main(PyThreadState *tstate, struct sync_module *main) { - assert(exc != NULL); - assert(PyErr_GivenExceptionMatches(exc, PyExc_AttributeError)); - int res = -1; + // Load the module from the original file (or from a cache). - PyObject *msgobj = pyerr_get_message(exc); - if (msgobj == NULL) { + // First try the local cache. + if (main->cached.failed != NULL) { + // We'll deal with this in apply_isolated_main(). + assert(main->cached.module == NULL); + assert(main->cached.loaded == NULL); + return 0; + } + else if (main->cached.loaded != NULL) { + assert(main->cached.module != NULL); + return 0; + } + assert(main->cached.module == NULL); + + if (main->filename == NULL) { + _PyErr_SetString(tstate, PyExc_NotImplementedError, ""); return -1; } - const char *err = PyUnicode_AsUTF8(msgobj); - if (strncmp(err, "module '", 8) != 0) { - goto finally; + // It wasn't in the local cache so we'll need to populate it. + PyObject *mod = _Py_GetMainModule(tstate); + if (_Py_CheckMainModule(mod) < 0) { + // This is probably unrecoverable, so don't bother caching the error. + assert(_PyErr_Occurred(tstate)); + Py_XDECREF(mod); + return -1; } - err += 8; + PyObject *loaded = NULL; - const char *matched = strchr(err, '\''); - if (matched == NULL) { - goto finally; + // Try the per-interpreter cache for the loaded module. + // XXX Store it in sys.modules? + PyObject *interpns = PyInterpreterState_GetDict(tstate->interp); + assert(interpns != NULL); + PyObject *key = PyUnicode_FromString("CACHED_MODULE_NS___main__"); + if (key == NULL) { + // It's probably unrecoverable, so don't bother caching the error. + Py_DECREF(mod); + return -1; } - Py_ssize_t len = matched - err; - if (len > MAX_MODNAME) { - goto finally; + else if (PyDict_GetItemRef(interpns, key, &loaded) < 0) { + // It's probably unrecoverable, so don't bother caching the error. + Py_DECREF(mod); + Py_DECREF(key); + return -1; } - (void)strncpy(info->modname, err, len); - info->modname[len] = '\0'; - err = matched; + else if (loaded == NULL) { + // It wasn't already loaded from file. + loaded = PyModule_NewObject(&_Py_ID(__main__)); + if (loaded == NULL) { + goto error; + } + PyObject *ns = _PyModule_GetDict(loaded); - if (strncmp(err, "' has no attribute '", 20) != 0) { - goto finally; - } - err += 20; + // We don't want to trigger "if __name__ == '__main__':", + // so we use a bogus module name. + PyObject *loaded_ns = + runpy_run_path(main->filename, "<fake __main__>"); + if (loaded_ns == NULL) { + goto error; + } + int res = PyDict_Update(ns, loaded_ns); + Py_DECREF(loaded_ns); + if (res < 0) { + goto error; + } - matched = strchr(err, '\''); - if (matched == NULL) { - goto finally; - } - len = matched - err; - if (len > MAX_ATTRNAME) { - goto finally; + // Set the per-interpreter cache entry. + if (PyDict_SetItem(interpns, key, loaded) < 0) { + goto error; + } } - (void)strncpy(info->attrname, err, len); - info->attrname[len] = '\0'; - err = matched + 1; - if (strlen(err) > 0) { - goto finally; + Py_DECREF(key); + main->cached = (struct sync_module_result){ + .module = mod, + .loaded = loaded, + }; + return 0; + +error: + sync_module_capture_exc(tstate, main); + Py_XDECREF(loaded); + Py_DECREF(mod); + Py_XDECREF(key); + return -1; +} + +#ifndef NDEBUG +static int +main_mod_matches(PyObject *expected) +{ + PyObject *mod = PyImport_GetModule(&_Py_ID(__main__)); + Py_XDECREF(mod); + return mod == expected; +} +#endif + +static int +apply_isolated_main(PyThreadState *tstate, struct sync_module *main) +{ + assert((main->cached.loaded == NULL) == (main->cached.loaded == NULL)); + if (main->cached.failed != NULL) { + // It must have failed previously. + assert(main->cached.loaded == NULL); + _PyErr_SetRaisedException(tstate, main->cached.failed); + return -1; } - res = 0; + assert(main->cached.loaded != NULL); -finally: - Py_DECREF(msgobj); - return res; + assert(main_mod_matches(main->cached.module)); + if (_PyImport_SetModule(&_Py_ID(__main__), main->cached.loaded) < 0) { + sync_module_capture_exc(tstate, main); + return -1; + } + return 0; } -#undef MAX_MODNAME -#undef MAX_ATTRNAME +static void +restore_main(PyThreadState *tstate, struct sync_module *main) +{ + assert(main->cached.failed == NULL); + assert(main->cached.module != NULL); + assert(main->cached.loaded != NULL); + PyObject *exc = _PyErr_GetRaisedException(tstate); + assert(main_mod_matches(main->cached.loaded)); + int res = _PyImport_SetModule(&_Py_ID(__main__), main->cached.module); + assert(res == 0); + if (res < 0) { + PyErr_FormatUnraisable("Exception ignored while restoring __main__"); + } + _PyErr_SetRaisedException(tstate, exc); +} /**************/ @@ -209,16 +288,16 @@ _Py_CallInInterpreterAndRawFree(PyInterpreterState *interp, /* cross-interpreter data */ /**************************/ -/* registry of {type -> xidatafunc} */ +/* registry of {type -> _PyXIData_getdata_t} */ -/* For now we use a global registry of shareable classes. An - alternative would be to add a tp_* slot for a class's - xidatafunc. It would be simpler and more efficient. */ +/* For now we use a global registry of shareable classes. + An alternative would be to add a tp_* slot for a class's + _PyXIData_getdata_t. It would be simpler and more efficient. */ static void xid_lookup_init(_PyXIData_lookup_t *); static void xid_lookup_fini(_PyXIData_lookup_t *); struct _dlcontext; -static xidatafunc lookup_getdata(struct _dlcontext *, PyObject *); +static _PyXIData_getdata_t lookup_getdata(struct _dlcontext *, PyObject *); #include "crossinterp_data_lookup.h" @@ -342,7 +421,7 @@ _set_xid_lookup_failure(PyThreadState *tstate, PyObject *obj, const char *msg, set_notshareableerror(tstate, cause, 0, msg); } else { - msg = "%S does not support cross-interpreter data"; + msg = "%R does not support cross-interpreter data"; format_notshareableerror(tstate, cause, 0, msg, obj); } } @@ -355,8 +434,8 @@ _PyObject_CheckXIData(PyThreadState *tstate, PyObject *obj) if (get_lookup_context(tstate, &ctx) < 0) { return -1; } - xidatafunc getdata = lookup_getdata(&ctx, obj); - if (getdata == NULL) { + _PyXIData_getdata_t getdata = lookup_getdata(&ctx, obj); + if (getdata.basic == NULL && getdata.fallback == NULL) { if (!_PyErr_Occurred(tstate)) { _set_xid_lookup_failure(tstate, obj, NULL, NULL); } @@ -387,9 +466,9 @@ _check_xidata(PyThreadState *tstate, _PyXIData_t *xidata) return 0; } -int -_PyObject_GetXIData(PyThreadState *tstate, - PyObject *obj, _PyXIData_t *xidata) +static int +_get_xidata(PyThreadState *tstate, + PyObject *obj, xidata_fallback_t fallback, _PyXIData_t *xidata) { PyInterpreterState *interp = tstate->interp; @@ -397,6 +476,7 @@ _PyObject_GetXIData(PyThreadState *tstate, assert(xidata->obj == NULL); if (xidata->data != NULL || xidata->obj != NULL) { _PyErr_SetString(tstate, PyExc_ValueError, "xidata not cleared"); + return -1; } // Call the "getdata" func for the object. @@ -405,8 +485,8 @@ _PyObject_GetXIData(PyThreadState *tstate, return -1; } Py_INCREF(obj); - xidatafunc getdata = lookup_getdata(&ctx, obj); - if (getdata == NULL) { + _PyXIData_getdata_t getdata = lookup_getdata(&ctx, obj); + if (getdata.basic == NULL && getdata.fallback == NULL) { if (PyErr_Occurred()) { Py_DECREF(obj); return -1; @@ -418,7 +498,9 @@ _PyObject_GetXIData(PyThreadState *tstate, } return -1; } - int res = getdata(tstate, obj, xidata); + int res = getdata.basic != NULL + ? getdata.basic(tstate, obj, xidata) + : getdata.fallback(tstate, obj, fallback, xidata); Py_DECREF(obj); if (res != 0) { PyObject *cause = _PyErr_GetRaisedException(tstate); @@ -438,6 +520,51 @@ _PyObject_GetXIData(PyThreadState *tstate, return 0; } +int +_PyObject_GetXIDataNoFallback(PyThreadState *tstate, + PyObject *obj, _PyXIData_t *xidata) +{ + return _get_xidata(tstate, obj, _PyXIDATA_XIDATA_ONLY, xidata); +} + +int +_PyObject_GetXIData(PyThreadState *tstate, + PyObject *obj, xidata_fallback_t fallback, + _PyXIData_t *xidata) +{ + switch (fallback) { + case _PyXIDATA_XIDATA_ONLY: + return _get_xidata(tstate, obj, fallback, xidata); + case _PyXIDATA_FULL_FALLBACK: + if (_get_xidata(tstate, obj, fallback, xidata) == 0) { + return 0; + } + PyObject *exc = _PyErr_GetRaisedException(tstate); + if (PyFunction_Check(obj)) { + if (_PyFunction_GetXIData(tstate, obj, xidata) == 0) { + Py_DECREF(exc); + return 0; + } + _PyErr_Clear(tstate); + } + // We could try _PyMarshal_GetXIData() but we won't for now. + if (_PyPickle_GetXIData(tstate, obj, xidata) == 0) { + Py_DECREF(exc); + return 0; + } + // Raise the original exception. + _PyErr_SetRaisedException(tstate, exc); + return -1; + default: +#ifdef Py_DEBUG + Py_FatalError("unsupported xidata fallback option"); +#endif + _PyErr_SetString(tstate, PyExc_SystemError, + "unsupported xidata fallback option"); + return -1; + } +} + /* pickle C-API */ @@ -458,28 +585,6 @@ _PyPickle_Dumps(struct _pickle_context *ctx, PyObject *obj) } -struct sync_module_result { - PyObject *module; - PyObject *loaded; - PyObject *failed; -}; - -struct sync_module { - const char *filename; - char _filename[MAXPATHLEN+1]; - struct sync_module_result cached; -}; - -static void -sync_module_clear(struct sync_module *data) -{ - data->filename = NULL; - Py_CLEAR(data->cached.module); - Py_CLEAR(data->cached.loaded); - Py_CLEAR(data->cached.failed); -} - - struct _unpickle_context { PyThreadState *tstate; // We only special-case the __main__ module, @@ -493,142 +598,88 @@ _unpickle_context_clear(struct _unpickle_context *ctx) sync_module_clear(&ctx->main); } -static struct sync_module_result -_unpickle_context_get_module(struct _unpickle_context *ctx, - const char *modname) +static int +check_missing___main___attr(PyObject *exc) { - if (strcmp(modname, "__main__") == 0) { - return ctx->main.cached; + assert(!PyErr_Occurred()); + if (!PyErr_GivenExceptionMatches(exc, PyExc_AttributeError)) { + return 0; } - else { - return (struct sync_module_result){ - .failed = PyExc_NotImplementedError, - }; + + // Get the error message. + PyObject *args = PyException_GetArgs(exc); + if (args == NULL || args == Py_None || PyObject_Size(args) < 1) { + assert(!PyErr_Occurred()); + return 0; } + PyObject *msgobj = args; + if (!PyUnicode_Check(msgobj)) { + msgobj = PySequence_GetItem(args, 0); + Py_DECREF(args); + if (msgobj == NULL) { + PyErr_Clear(); + return 0; + } + } + const char *err = PyUnicode_AsUTF8(msgobj); + + // Check if it's a missing __main__ attr. + int cmp = strncmp(err, "module '__main__' has no attribute '", 36); + Py_DECREF(msgobj); + return cmp == 0; } -static struct sync_module_result -_unpickle_context_set_module(struct _unpickle_context *ctx, - const char *modname) +static PyObject * +_PyPickle_Loads(struct _unpickle_context *ctx, PyObject *pickled) { - struct sync_module_result res = {0}; - struct sync_module_result *cached = NULL; - const char *filename = NULL; - const char *run_modname = modname; - if (strcmp(modname, "__main__") == 0) { - cached = &ctx->main.cached; - filename = ctx->main.filename; - // We don't want to trigger "if __name__ == '__main__':". - run_modname = "<fake __main__>"; - } - else { - res.failed = PyExc_NotImplementedError; - goto finally; - } + PyThreadState *tstate = ctx->tstate; - res.module = import_get_module(ctx->tstate, modname); - if (res.module == NULL) { - res.failed = _PyErr_GetRaisedException(ctx->tstate); - assert(res.failed != NULL); - goto finally; + PyObject *exc = NULL; + PyObject *loads = PyImport_ImportModuleAttrString("pickle", "loads"); + if (loads == NULL) { + return NULL; } - if (filename == NULL) { - Py_CLEAR(res.module); - res.failed = PyExc_NotImplementedError; + // Make an initial attempt to unpickle. + PyObject *obj = PyObject_CallOneArg(loads, pickled); + if (obj != NULL) { goto finally; } - res.loaded = runpy_run_path(filename, run_modname); - if (res.loaded == NULL) { - Py_CLEAR(res.module); - res.failed = _PyErr_GetRaisedException(ctx->tstate); - assert(res.failed != NULL); + assert(_PyErr_Occurred(tstate)); + if (ctx == NULL) { goto finally; } - -finally: - if (cached != NULL) { - assert(cached->module == NULL); - assert(cached->loaded == NULL); - assert(cached->failed == NULL); - *cached = res; - } - return res; -} - - -static int -_handle_unpickle_missing_attr(struct _unpickle_context *ctx, PyObject *exc) -{ - // The caller must check if an exception is set or not when -1 is returned. - assert(!_PyErr_Occurred(ctx->tstate)); - assert(PyErr_GivenExceptionMatches(exc, PyExc_AttributeError)); - struct attributeerror_info info; - if (_parse_attributeerror(exc, &info) < 0) { - return -1; + exc = _PyErr_GetRaisedException(tstate); + if (!check_missing___main___attr(exc)) { + goto finally; } - // Get the module. - struct sync_module_result mod = _unpickle_context_get_module(ctx, info.modname); - if (mod.failed != NULL) { - // It must have failed previously. - return -1; - } - if (mod.module == NULL) { - mod = _unpickle_context_set_module(ctx, info.modname); - if (mod.failed != NULL) { - return -1; - } - assert(mod.module != NULL); + // Temporarily swap in a fake __main__ loaded from the original + // file and cached. Note that functions will use the cached ns + // for __globals__, // not the actual module. + if (ensure_isolated_main(tstate, &ctx->main) < 0) { + goto finally; } - - // Bail out if it is unexpectedly set already. - if (PyObject_HasAttrString(mod.module, info.attrname)) { - return -1; + if (apply_isolated_main(tstate, &ctx->main) < 0) { + goto finally; } - // Try setting the attribute. - PyObject *value = NULL; - if (PyDict_GetItemStringRef(mod.loaded, info.attrname, &value) <= 0) { - return -1; - } - assert(value != NULL); - int res = PyObject_SetAttrString(mod.module, info.attrname, value); - Py_DECREF(value); - if (res < 0) { - return -1; + // Try to unpickle once more. + obj = PyObject_CallOneArg(loads, pickled); + restore_main(tstate, &ctx->main); + if (obj == NULL) { + goto finally; } + Py_CLEAR(exc); - return 0; -} - -static PyObject * -_PyPickle_Loads(struct _unpickle_context *ctx, PyObject *pickled) -{ - PyObject *loads = PyImport_ImportModuleAttrString("pickle", "loads"); - if (loads == NULL) { - return NULL; - } - PyObject *obj = PyObject_CallOneArg(loads, pickled); - if (ctx != NULL) { - while (obj == NULL) { - assert(_PyErr_Occurred(ctx->tstate)); - if (!PyErr_ExceptionMatches(PyExc_AttributeError)) { - // We leave other failures unhandled. - break; - } - // Try setting the attr if not set. - PyObject *exc = _PyErr_GetRaisedException(ctx->tstate); - if (_handle_unpickle_missing_attr(ctx, exc) < 0) { - // Any resulting exceptions are ignored - // in favor of the original. - _PyErr_SetRaisedException(ctx->tstate, exc); - break; - } - Py_CLEAR(exc); - // Retry with the attribute set. - obj = PyObject_CallOneArg(loads, pickled); +finally: + if (exc != NULL) { + if (_PyErr_Occurred(tstate)) { + sync_module_capture_exc(tstate, &ctx->main); } + // We restore the original exception. + // It might make sense to chain it (__context__). + _PyErr_SetRaisedException(tstate, exc); } Py_DECREF(loads); return obj; @@ -859,8 +910,15 @@ get_script_xidata(PyThreadState *tstate, PyObject *obj, int pure, } goto error; } +#ifdef Py_GIL_DISABLED + // Don't immortalize code constants to avoid memory leaks. + ((_PyThreadStateImpl *)tstate)->suppress_co_const_immortalization++; +#endif code = Py_CompileStringExFlags( script, filename, Py_file_input, &cf, optimize); +#ifdef Py_GIL_DISABLED + ((_PyThreadStateImpl *)tstate)->suppress_co_const_immortalization--; +#endif Py_XDECREF(ref); if (code == NULL) { goto error; @@ -1257,8 +1315,14 @@ _excinfo_normalize_type(struct _excinfo_type *info, *p_module = module; } +static int +excinfo_is_set(_PyXI_excinfo *info) +{ + return info->type.name != NULL || info->msg != NULL; +} + static void -_PyXI_excinfo_Clear(_PyXI_excinfo *info) +_PyXI_excinfo_clear(_PyXI_excinfo *info) { _excinfo_clear_type(&info->type); if (info->msg != NULL) { @@ -1308,7 +1372,7 @@ _PyXI_excinfo_InitFromException(_PyXI_excinfo *info, PyObject *exc) assert(exc != NULL); if (PyErr_GivenExceptionMatches(exc, PyExc_MemoryError)) { - _PyXI_excinfo_Clear(info); + _PyXI_excinfo_clear(info); return NULL; } const char *failure = NULL; @@ -1354,7 +1418,7 @@ _PyXI_excinfo_InitFromException(_PyXI_excinfo *info, PyObject *exc) error: assert(failure != NULL); - _PyXI_excinfo_Clear(info); + _PyXI_excinfo_clear(info); return failure; } @@ -1405,7 +1469,7 @@ _PyXI_excinfo_InitFromObject(_PyXI_excinfo *info, PyObject *obj) error: assert(failure != NULL); - _PyXI_excinfo_Clear(info); + _PyXI_excinfo_clear(info); return failure; } @@ -1418,6 +1482,11 @@ _PyXI_excinfo_Apply(_PyXI_excinfo *info, PyObject *exctype) if (tbexc == NULL) { PyErr_Clear(); } + else { + PyErr_SetObject(exctype, tbexc); + Py_DECREF(tbexc); + return; + } } PyObject *formatted = _PyXI_excinfo_format(info); @@ -1563,13 +1632,17 @@ error: } -int -_PyXI_InitExcInfo(_PyXI_excinfo *info, PyObject *exc) +_PyXI_excinfo * +_PyXI_NewExcInfo(PyObject *exc) { assert(!PyErr_Occurred()); if (exc == NULL || exc == Py_None) { PyErr_SetString(PyExc_ValueError, "missing exc"); - return -1; + return NULL; + } + _PyXI_excinfo *info = PyMem_RawCalloc(1, sizeof(_PyXI_excinfo)); + if (info == NULL) { + return NULL; } const char *failure; if (PyExceptionInstance_Check(exc) || PyExceptionClass_Check(exc)) { @@ -1579,10 +1652,18 @@ _PyXI_InitExcInfo(_PyXI_excinfo *info, PyObject *exc) failure = _PyXI_excinfo_InitFromObject(info, exc); } if (failure != NULL) { - PyErr_SetString(PyExc_Exception, failure); - return -1; + PyMem_RawFree(info); + set_exc_with_cause(PyExc_Exception, failure); + return NULL; } - return 0; + return info; +} + +void +_PyXI_FreeExcInfo(_PyXI_excinfo *info) +{ + _PyXI_excinfo_clear(info); + PyMem_RawFree(info); } PyObject * @@ -1597,12 +1678,6 @@ _PyXI_ExcInfoAsObject(_PyXI_excinfo *info) return _PyXI_excinfo_AsObject(info); } -void -_PyXI_ClearExcInfo(_PyXI_excinfo *info) -{ - _PyXI_excinfo_Clear(info); -} - /***************************/ /* short-term data sharing */ @@ -1616,14 +1691,9 @@ _PyXI_ApplyErrorCode(_PyXI_errcode code, PyInterpreterState *interp) PyThreadState *tstate = _PyThreadState_GET(); assert(!PyErr_Occurred()); + assert(code != _PyXI_ERR_NO_ERROR); + assert(code != _PyXI_ERR_UNCAUGHT_EXCEPTION); switch (code) { - case _PyXI_ERR_NO_ERROR: _Py_FALLTHROUGH; - case _PyXI_ERR_UNCAUGHT_EXCEPTION: - // There is nothing to apply. -#ifdef Py_DEBUG - Py_UNREACHABLE(); -#endif - return 0; case _PyXI_ERR_OTHER: // XXX msg? PyErr_SetNone(PyExc_InterpreterError); @@ -1643,12 +1713,20 @@ _PyXI_ApplyErrorCode(_PyXI_errcode code, PyInterpreterState *interp) PyErr_SetString(PyExc_InterpreterError, "failed to apply namespace to __main__"); break; + case _PyXI_ERR_PRESERVE_FAILURE: + PyErr_SetString(PyExc_InterpreterError, + "failed to preserve objects across session"); + break; + case _PyXI_ERR_EXC_PROPAGATION_FAILURE: + PyErr_SetString(PyExc_InterpreterError, + "failed to transfer exception between interpreters"); + break; case _PyXI_ERR_NOT_SHAREABLE: _set_xid_lookup_failure(tstate, NULL, NULL, NULL); break; default: #ifdef Py_DEBUG - Py_UNREACHABLE(); + Py_FatalError("unsupported error code"); #else PyErr_Format(PyExc_RuntimeError, "unsupported error code %d", code); #endif @@ -1657,70 +1735,267 @@ _PyXI_ApplyErrorCode(_PyXI_errcode code, PyInterpreterState *interp) return -1; } +/* basic failure info */ + +struct xi_failure { + // The kind of error to propagate. + _PyXI_errcode code; + // The propagated message. + const char *msg; + int msg_owned; +}; // _PyXI_failure + +#define XI_FAILURE_INIT (_PyXI_failure){ .code = _PyXI_ERR_NO_ERROR } + +static void +clear_xi_failure(_PyXI_failure *failure) +{ + if (failure->msg != NULL && failure->msg_owned) { + PyMem_RawFree((void*)failure->msg); + } + *failure = XI_FAILURE_INIT; +} + +static void +copy_xi_failure(_PyXI_failure *dest, _PyXI_failure *src) +{ + *dest = *src; + dest->msg_owned = 0; +} + +_PyXI_failure * +_PyXI_NewFailure(void) +{ + _PyXI_failure *failure = PyMem_RawMalloc(sizeof(_PyXI_failure)); + if (failure == NULL) { + PyErr_NoMemory(); + return NULL; + } + *failure = XI_FAILURE_INIT; + return failure; +} + +void +_PyXI_FreeFailure(_PyXI_failure *failure) +{ + clear_xi_failure(failure); + PyMem_RawFree(failure); +} + +_PyXI_errcode +_PyXI_GetFailureCode(_PyXI_failure *failure) +{ + if (failure == NULL) { + return _PyXI_ERR_NO_ERROR; + } + return failure->code; +} + +void +_PyXI_InitFailureUTF8(_PyXI_failure *failure, + _PyXI_errcode code, const char *msg) +{ + *failure = (_PyXI_failure){ + .code = code, + .msg = msg, + .msg_owned = 0, + }; +} + +int +_PyXI_InitFailure(_PyXI_failure *failure, _PyXI_errcode code, PyObject *obj) +{ + PyObject *msgobj = PyObject_Str(obj); + if (msgobj == NULL) { + return -1; + } + // This will leak if not paired with clear_xi_failure(). + // That happens automatically in _capture_current_exception(). + const char *msg = _copy_string_obj_raw(msgobj, NULL); + Py_DECREF(msgobj); + if (PyErr_Occurred()) { + return -1; + } + *failure = (_PyXI_failure){ + .code = code, + .msg = msg, + .msg_owned = 1, + }; + return 0; +} + /* shared exceptions */ -static const char * -_PyXI_InitError(_PyXI_error *error, PyObject *excobj, _PyXI_errcode code) +typedef struct { + // The originating interpreter. + PyInterpreterState *interp; + // The error to propagate, if different from the uncaught exception. + _PyXI_failure *override; + _PyXI_failure _override; + // The exception information to propagate, if applicable. + // This is populated only for some error codes, + // but always for _PyXI_ERR_UNCAUGHT_EXCEPTION. + _PyXI_excinfo uncaught; +} _PyXI_error; + +static void +xi_error_clear(_PyXI_error *err) { - if (error->interp == NULL) { - error->interp = PyInterpreterState_Get(); + err->interp = NULL; + if (err->override != NULL) { + clear_xi_failure(err->override); } + _PyXI_excinfo_clear(&err->uncaught); +} - const char *failure = NULL; - if (code == _PyXI_ERR_UNCAUGHT_EXCEPTION) { - // There is an unhandled exception we need to propagate. - failure = _PyXI_excinfo_InitFromException(&error->uncaught, excobj); - if (failure != NULL) { - // We failed to initialize error->uncaught. - // XXX Print the excobj/traceback? Emit a warning? - // XXX Print the current exception/traceback? - if (PyErr_ExceptionMatches(PyExc_MemoryError)) { - error->code = _PyXI_ERR_NO_MEMORY; - } - else { - error->code = _PyXI_ERR_OTHER; - } - PyErr_Clear(); +static int +xi_error_is_set(_PyXI_error *error) +{ + if (error->override != NULL) { + assert(error->override->code != _PyXI_ERR_NO_ERROR); + assert(error->override->code != _PyXI_ERR_UNCAUGHT_EXCEPTION + || excinfo_is_set(&error->uncaught)); + return 1; + } + return excinfo_is_set(&error->uncaught); +} + +static int +xi_error_has_override(_PyXI_error *err) +{ + if (err->override == NULL) { + return 0; + } + return (err->override->code != _PyXI_ERR_NO_ERROR + && err->override->code != _PyXI_ERR_UNCAUGHT_EXCEPTION); +} + +static PyObject * +xi_error_resolve_current_exc(PyThreadState *tstate, + _PyXI_failure *override) +{ + assert(override == NULL || override->code != _PyXI_ERR_NO_ERROR); + + PyObject *exc = _PyErr_GetRaisedException(tstate); + if (exc == NULL) { + assert(override == NULL + || override->code != _PyXI_ERR_UNCAUGHT_EXCEPTION); + } + else if (override == NULL) { + // This is equivalent to _PyXI_ERR_UNCAUGHT_EXCEPTION. + } + else if (override->code == _PyXI_ERR_UNCAUGHT_EXCEPTION) { + // We want to actually capture the current exception. + } + else if (exc != NULL) { + // It might make sense to do similarly for other codes. + if (override->code == _PyXI_ERR_ALREADY_RUNNING) { + // We don't need the exception info. + Py_CLEAR(exc); + } + // ...else we want to actually capture the current exception. + } + return exc; +} + +static void +xi_error_set_override(PyThreadState *tstate, _PyXI_error *err, + _PyXI_failure *override) +{ + assert(err->override == NULL); + assert(override != NULL); + assert(override->code != _PyXI_ERR_NO_ERROR); + // Use xi_error_set_exc() instead of setting _PyXI_ERR_UNCAUGHT_EXCEPTION.. + assert(override->code != _PyXI_ERR_UNCAUGHT_EXCEPTION); + err->override = &err->_override; + // The caller still owns override->msg. + copy_xi_failure(&err->_override, override); + err->interp = tstate->interp; +} + +static void +xi_error_set_override_code(PyThreadState *tstate, _PyXI_error *err, + _PyXI_errcode code) +{ + _PyXI_failure override = XI_FAILURE_INIT; + override.code = code; + xi_error_set_override(tstate, err, &override); +} + +static const char * +xi_error_set_exc(PyThreadState *tstate, _PyXI_error *err, PyObject *exc) +{ + assert(!_PyErr_Occurred(tstate)); + assert(!xi_error_is_set(err)); + assert(err->override == NULL); + assert(err->interp == NULL); + assert(exc != NULL); + const char *failure = + _PyXI_excinfo_InitFromException(&err->uncaught, exc); + if (failure != NULL) { + // We failed to initialize err->uncaught. + // XXX Print the excobj/traceback? Emit a warning? + // XXX Print the current exception/traceback? + if (_PyErr_ExceptionMatches(tstate, PyExc_MemoryError)) { + xi_error_set_override_code(tstate, err, _PyXI_ERR_NO_MEMORY); } else { - error->code = code; + xi_error_set_override_code(tstate, err, _PyXI_ERR_OTHER); } - assert(error->code != _PyXI_ERR_NO_ERROR); - } - else { - // There is an error code we need to propagate. - assert(excobj == NULL); - assert(code != _PyXI_ERR_NO_ERROR); - error->code = code; - _PyXI_excinfo_Clear(&error->uncaught); + PyErr_Clear(); } return failure; } -PyObject * -_PyXI_ApplyError(_PyXI_error *error) +static PyObject * +_PyXI_ApplyError(_PyXI_error *error, const char *failure) { PyThreadState *tstate = PyThreadState_Get(); - if (error->code == _PyXI_ERR_UNCAUGHT_EXCEPTION) { - // Raise an exception that proxies the propagated exception. + + if (failure != NULL) { + xi_error_clear(error); + return NULL; + } + + _PyXI_errcode code = _PyXI_ERR_UNCAUGHT_EXCEPTION; + if (error->override != NULL) { + code = error->override->code; + assert(code != _PyXI_ERR_NO_ERROR); + } + + if (code == _PyXI_ERR_UNCAUGHT_EXCEPTION) { + // We will raise an exception that proxies the propagated exception. return _PyXI_excinfo_AsObject(&error->uncaught); } - else if (error->code == _PyXI_ERR_NOT_SHAREABLE) { + else if (code == _PyXI_ERR_NOT_SHAREABLE) { // Propagate the exception directly. assert(!_PyErr_Occurred(tstate)); - _set_xid_lookup_failure(tstate, NULL, error->uncaught.msg, NULL); + PyObject *cause = NULL; + if (excinfo_is_set(&error->uncaught)) { + // Maybe instead set a PyExc_ExceptionSnapshot as __cause__? + // That type doesn't exist currently + // but would look like interpreters.ExecutionFailed. + _PyXI_excinfo_Apply(&error->uncaught, PyExc_Exception); + cause = _PyErr_GetRaisedException(tstate); + } + const char *msg = error->override != NULL + ? error->override->msg + : error->uncaught.msg; + _set_xid_lookup_failure(tstate, NULL, msg, cause); + Py_XDECREF(cause); } else { // Raise an exception corresponding to the code. - assert(error->code != _PyXI_ERR_NO_ERROR); - (void)_PyXI_ApplyErrorCode(error->code, error->interp); - if (error->uncaught.type.name != NULL || error->uncaught.msg != NULL) { + (void)_PyXI_ApplyErrorCode(code, error->interp); + assert(error->override == NULL || error->override->msg == NULL); + if (excinfo_is_set(&error->uncaught)) { // __context__ will be set to a proxy of the propagated exception. - PyObject *exc = PyErr_GetRaisedException(); + // (or use PyExc_ExceptionSnapshot like _PyXI_ERR_NOT_SHAREABLE?) + PyObject *exc = _PyErr_GetRaisedException(tstate); _PyXI_excinfo_Apply(&error->uncaught, PyExc_InterpreterError); - PyObject *exc2 = PyErr_GetRaisedException(); + PyObject *exc2 = _PyErr_GetRaisedException(tstate); PyException_SetContext(exc, exc2); - PyErr_SetRaisedException(exc); + _PyErr_SetRaisedException(tstate, exc); } } assert(PyErr_Occurred()); @@ -1751,6 +2026,7 @@ typedef struct _sharednsitem { // in a different interpreter to release the XI data. } _PyXI_namespace_item; +#ifndef NDEBUG static int _sharednsitem_is_initialized(_PyXI_namespace_item *item) { @@ -1759,6 +2035,7 @@ _sharednsitem_is_initialized(_PyXI_namespace_item *item) } return 0; } +#endif static int _sharednsitem_init(_PyXI_namespace_item *item, PyObject *key) @@ -1786,7 +2063,8 @@ _sharednsitem_has_value(_PyXI_namespace_item *item, int64_t *p_interpid) } static int -_sharednsitem_set_value(_PyXI_namespace_item *item, PyObject *value) +_sharednsitem_set_value(_PyXI_namespace_item *item, PyObject *value, + xidata_fallback_t fallback) { assert(_sharednsitem_is_initialized(item)); assert(item->xidata == NULL); @@ -1795,7 +2073,7 @@ _sharednsitem_set_value(_PyXI_namespace_item *item, PyObject *value) return -1; } PyThreadState *tstate = PyThreadState_Get(); - if (_PyObject_GetXIData(tstate, value, item->xidata) != 0) { + if (_PyObject_GetXIData(tstate, value, fallback, item->xidata) < 0) { PyMem_RawFree(item->xidata); item->xidata = NULL; // The caller may want to propagate PyExc_NotShareableError @@ -1827,7 +2105,8 @@ _sharednsitem_clear(_PyXI_namespace_item *item) } static int -_sharednsitem_copy_from_ns(struct _sharednsitem *item, PyObject *ns) +_sharednsitem_copy_from_ns(struct _sharednsitem *item, PyObject *ns, + xidata_fallback_t fallback) { assert(item->name != NULL); assert(item->xidata == NULL); @@ -1839,7 +2118,7 @@ _sharednsitem_copy_from_ns(struct _sharednsitem *item, PyObject *ns) // When applied, this item will be set to the default (or fail). return 0; } - if (_sharednsitem_set_value(item, value) < 0) { + if (_sharednsitem_set_value(item, value, fallback) < 0) { return -1; } return 0; @@ -1869,156 +2148,212 @@ _sharednsitem_apply(_PyXI_namespace_item *item, PyObject *ns, PyObject *dflt) return res; } -struct _sharedns { - Py_ssize_t len; - _PyXI_namespace_item *items; -}; -static _PyXI_namespace * -_sharedns_new(void) -{ - _PyXI_namespace *ns = PyMem_RawCalloc(sizeof(_PyXI_namespace), 1); - if (ns == NULL) { - PyErr_NoMemory(); - return NULL; - } - *ns = (_PyXI_namespace){ 0 }; - return ns; -} +typedef struct { + Py_ssize_t maxitems; + Py_ssize_t numnames; + Py_ssize_t numvalues; + _PyXI_namespace_item items[1]; +} _PyXI_namespace; +#ifndef NDEBUG static int -_sharedns_is_initialized(_PyXI_namespace *ns) +_sharedns_check_counts(_PyXI_namespace *ns) { - if (ns->len == 0) { - assert(ns->items == NULL); + if (ns->maxitems <= 0) { + return 0; + } + if (ns->numnames < 0) { + return 0; + } + if (ns->numnames > ns->maxitems) { + return 0; + } + if (ns->numvalues < 0) { + return 0; + } + if (ns->numvalues > ns->numnames) { return 0; } - - assert(ns->len > 0); - assert(ns->items != NULL); - assert(_sharednsitem_is_initialized(&ns->items[0])); - assert(ns->len == 1 - || _sharednsitem_is_initialized(&ns->items[ns->len - 1])); return 1; } -#define HAS_COMPLETE_DATA 1 -#define HAS_PARTIAL_DATA 2 - static int -_sharedns_has_xidata(_PyXI_namespace *ns, int64_t *p_interpid) +_sharedns_check_consistency(_PyXI_namespace *ns) { - // We expect _PyXI_namespace to always be initialized. - assert(_sharedns_is_initialized(ns)); - int res = 0; - _PyXI_namespace_item *item0 = &ns->items[0]; - if (!_sharednsitem_is_initialized(item0)) { + if (!_sharedns_check_counts(ns)) { return 0; } - int64_t interpid0 = -1; - if (!_sharednsitem_has_value(item0, &interpid0)) { - return 0; + + Py_ssize_t i = 0; + _PyXI_namespace_item *item; + if (ns->numvalues > 0) { + item = &ns->items[0]; + if (!_sharednsitem_is_initialized(item)) { + return 0; + } + int64_t interpid0 = -1; + if (!_sharednsitem_has_value(item, &interpid0)) { + return 0; + } + i += 1; + for (; i < ns->numvalues; i++) { + item = &ns->items[i]; + if (!_sharednsitem_is_initialized(item)) { + return 0; + } + int64_t interpid = -1; + if (!_sharednsitem_has_value(item, &interpid)) { + return 0; + } + if (interpid != interpid0) { + return 0; + } + } } - if (ns->len > 1) { - // At this point we know it is has at least partial data. - _PyXI_namespace_item *itemN = &ns->items[ns->len-1]; - if (!_sharednsitem_is_initialized(itemN)) { - res = HAS_PARTIAL_DATA; - goto finally; + for (; i < ns->numnames; i++) { + item = &ns->items[i]; + if (!_sharednsitem_is_initialized(item)) { + return 0; } - int64_t interpidN = -1; - if (!_sharednsitem_has_value(itemN, &interpidN)) { - res = HAS_PARTIAL_DATA; - goto finally; + if (_sharednsitem_has_value(item, NULL)) { + return 0; } - assert(interpidN == interpid0); } - res = HAS_COMPLETE_DATA; - *p_interpid = interpid0; - -finally: - return res; + for (; i < ns->maxitems; i++) { + item = &ns->items[i]; + if (_sharednsitem_is_initialized(item)) { + return 0; + } + if (_sharednsitem_has_value(item, NULL)) { + return 0; + } + } + return 1; } +#endif -static void -_sharedns_clear(_PyXI_namespace *ns) +static _PyXI_namespace * +_sharedns_alloc(Py_ssize_t maxitems) { - if (!_sharedns_is_initialized(ns)) { - return; + if (maxitems < 0) { + if (!PyErr_Occurred()) { + PyErr_BadInternalCall(); + } + return NULL; + } + else if (maxitems == 0) { + PyErr_SetString(PyExc_ValueError, "empty namespaces not allowed"); + return NULL; + } + + // Check for overflow. + size_t fixedsize = sizeof(_PyXI_namespace) - sizeof(_PyXI_namespace_item); + if ((size_t)maxitems > + ((size_t)PY_SSIZE_T_MAX - fixedsize) / sizeof(_PyXI_namespace_item)) + { + PyErr_NoMemory(); + return NULL; } - // If the cross-interpreter data were allocated as part of - // _PyXI_namespace_item (instead of dynamically), this is where - // we would need verify that we are clearing the items in the - // correct interpreter, to avoid a race with releasing the XI data - // via a pending call. See _sharedns_has_xidata(). - for (Py_ssize_t i=0; i < ns->len; i++) { - _sharednsitem_clear(&ns->items[i]); + // Allocate the value, including items. + size_t size = fixedsize + sizeof(_PyXI_namespace_item) * maxitems; + + _PyXI_namespace *ns = PyMem_RawCalloc(size, 1); + if (ns == NULL) { + PyErr_NoMemory(); + return NULL; } - PyMem_RawFree(ns->items); - ns->items = NULL; - ns->len = 0; + ns->maxitems = maxitems; + assert(_sharedns_check_consistency(ns)); + return ns; } static void _sharedns_free(_PyXI_namespace *ns) { - _sharedns_clear(ns); + // If we weren't always dynamically allocating the cross-interpreter + // data in each item then we would need to use a pending call + // to call _sharedns_free(), to avoid the race between freeing + // the shared namespace and releasing the XI data. + assert(_sharedns_check_counts(ns)); + Py_ssize_t i = 0; + _PyXI_namespace_item *item; + if (ns->numvalues > 0) { + // One or more items may have interpreter-specific data. +#ifndef NDEBUG + int64_t interpid = PyInterpreterState_GetID(PyInterpreterState_Get()); + int64_t interpid_i; +#endif + for (; i < ns->numvalues; i++) { + item = &ns->items[i]; + assert(_sharednsitem_is_initialized(item)); + // While we do want to ensure consistency across items, + // technically they don't need to match the current + // interpreter. However, we keep the constraint for + // simplicity, by giving _PyXI_FreeNamespace() the exclusive + // responsibility of dealing with the owning interpreter. + assert(_sharednsitem_has_value(item, &interpid_i)); + assert(interpid_i == interpid); + _sharednsitem_clear(item); + } + } + for (; i < ns->numnames; i++) { + item = &ns->items[i]; + assert(_sharednsitem_is_initialized(item)); + assert(!_sharednsitem_has_value(item, NULL)); + _sharednsitem_clear(item); + } +#ifndef NDEBUG + for (; i < ns->maxitems; i++) { + item = &ns->items[i]; + assert(!_sharednsitem_is_initialized(item)); + assert(!_sharednsitem_has_value(item, NULL)); + } +#endif + PyMem_RawFree(ns); } -static int -_sharedns_init(_PyXI_namespace *ns, PyObject *names) +static _PyXI_namespace * +_create_sharedns(PyObject *names) { - assert(!_sharedns_is_initialized(ns)); assert(names != NULL); - Py_ssize_t len = PyDict_CheckExact(names) + Py_ssize_t numnames = PyDict_CheckExact(names) ? PyDict_Size(names) : PySequence_Size(names); - if (len < 0) { - return -1; - } - if (len == 0) { - PyErr_SetString(PyExc_ValueError, "empty namespaces not allowed"); - return -1; - } - assert(len > 0); - // Allocate the items. - _PyXI_namespace_item *items = - PyMem_RawCalloc(sizeof(struct _sharednsitem), len); - if (items == NULL) { - PyErr_NoMemory(); - return -1; + _PyXI_namespace *ns = _sharedns_alloc(numnames); + if (ns == NULL) { + return NULL; } + _PyXI_namespace_item *items = ns->items; // Fill in the names. - Py_ssize_t i = -1; if (PyDict_CheckExact(names)) { + Py_ssize_t i = 0; Py_ssize_t pos = 0; - for (i=0; i < len; i++) { - PyObject *key; - if (!PyDict_Next(names, &pos, &key, NULL)) { - // This should not be possible. - assert(0); - goto error; - } - if (_sharednsitem_init(&items[i], key) < 0) { + PyObject *name; + while(PyDict_Next(names, &pos, &name, NULL)) { + if (_sharednsitem_init(&items[i], name) < 0) { goto error; } + ns->numnames += 1; + i += 1; } } else if (PySequence_Check(names)) { - for (i=0; i < len; i++) { - PyObject *key = PySequence_GetItem(names, i); - if (key == NULL) { + for (Py_ssize_t i = 0; i < numnames; i++) { + PyObject *name = PySequence_GetItem(names, i); + if (name == NULL) { goto error; } - int res = _sharednsitem_init(&items[i], key); - Py_DECREF(key); + int res = _sharednsitem_init(&items[i], name); + Py_DECREF(name); if (res < 0) { goto error; } + ns->numnames += 1; } } else { @@ -2026,140 +2361,84 @@ _sharedns_init(_PyXI_namespace *ns, PyObject *names) "non-sequence namespace not supported"); goto error; } - - ns->items = items; - ns->len = len; - assert(_sharedns_is_initialized(ns)); - return 0; + assert(ns->numnames == ns->maxitems); + return ns; error: - for (Py_ssize_t j=0; j < i; j++) { - _sharednsitem_clear(&items[j]); - } - PyMem_RawFree(items); - assert(!_sharedns_is_initialized(ns)); - return -1; + _sharedns_free(ns); + return NULL; } -void -_PyXI_FreeNamespace(_PyXI_namespace *ns) -{ - if (!_sharedns_is_initialized(ns)) { - return; - } +static void _propagate_not_shareable_error(PyThreadState *, + _PyXI_failure *); - int64_t interpid = -1; - if (!_sharedns_has_xidata(ns, &interpid)) { - _sharedns_free(ns); - return; - } - - if (interpid == PyInterpreterState_GetID(PyInterpreterState_Get())) { - _sharedns_free(ns); - } - else { - // If we weren't always dynamically allocating the cross-interpreter - // data in each item then we would need to using a pending call - // to call _sharedns_free(), to avoid the race between freeing - // the shared namespace and releasing the XI data. - _sharedns_free(ns); - } -} - -_PyXI_namespace * -_PyXI_NamespaceFromNames(PyObject *names) +static int +_fill_sharedns(_PyXI_namespace *ns, PyObject *nsobj, + xidata_fallback_t fallback, _PyXI_failure *p_err) { - if (names == NULL || names == Py_None) { - return NULL; - } - - _PyXI_namespace *ns = _sharedns_new(); - if (ns == NULL) { - return NULL; - } - - if (_sharedns_init(ns, names) < 0) { - PyMem_RawFree(ns); - if (PySequence_Size(names) == 0) { - PyErr_Clear(); - } - return NULL; - } - - return ns; -} - -#ifndef NDEBUG -static int _session_is_active(_PyXI_session *); -#endif -static void _propagate_not_shareable_error(_PyXI_session *); - -int -_PyXI_FillNamespaceFromDict(_PyXI_namespace *ns, PyObject *nsobj, - _PyXI_session *session) -{ - // session must be entered already, if provided. - assert(session == NULL || _session_is_active(session)); - assert(_sharedns_is_initialized(ns)); - for (Py_ssize_t i=0; i < ns->len; i++) { - _PyXI_namespace_item *item = &ns->items[i]; - if (_sharednsitem_copy_from_ns(item, nsobj) < 0) { - _propagate_not_shareable_error(session); + // All items are expected to be shareable. + assert(_sharedns_check_counts(ns)); + assert(ns->numnames == ns->maxitems); + assert(ns->numvalues == 0); + PyThreadState *tstate = PyThreadState_Get(); + for (Py_ssize_t i=0; i < ns->maxitems; i++) { + if (_sharednsitem_copy_from_ns(&ns->items[i], nsobj, fallback) < 0) { + if (p_err != NULL) { + _propagate_not_shareable_error(tstate, p_err); + } // Clear out the ones we set so far. for (Py_ssize_t j=0; j < i; j++) { _sharednsitem_clear_value(&ns->items[j]); + ns->numvalues -= 1; } return -1; } + ns->numvalues += 1; } return 0; } -// All items are expected to be shareable. -static _PyXI_namespace * -_PyXI_NamespaceFromDict(PyObject *nsobj, _PyXI_session *session) +static int +_sharedns_free_pending(void *data) { - // session must be entered already, if provided. - assert(session == NULL || _session_is_active(session)); - if (nsobj == NULL || nsobj == Py_None) { - return NULL; - } - if (!PyDict_CheckExact(nsobj)) { - PyErr_SetString(PyExc_TypeError, "expected a dict"); - return NULL; - } + _sharedns_free((_PyXI_namespace *)data); + return 0; +} - _PyXI_namespace *ns = _sharedns_new(); - if (ns == NULL) { - return NULL; +static void +_destroy_sharedns(_PyXI_namespace *ns) +{ + assert(_sharedns_check_counts(ns)); + assert(ns->numnames == ns->maxitems); + if (ns->numvalues == 0) { + _sharedns_free(ns); + return; } - if (_sharedns_init(ns, nsobj) < 0) { - if (PyDict_Size(nsobj) == 0) { - PyMem_RawFree(ns); - PyErr_Clear(); - return NULL; - } - goto error; + int64_t interpid0; + if (!_sharednsitem_has_value(&ns->items[0], &interpid0)) { + // This shouldn't have been possible. + // We can deal with it in _sharedns_free(). + _sharedns_free(ns); + return; } - - if (_PyXI_FillNamespaceFromDict(ns, nsobj, session) < 0) { - goto error; + PyInterpreterState *interp = _PyInterpreterState_LookUpID(interpid0); + if (interp == PyInterpreterState_Get()) { + _sharedns_free(ns); + return; } - return ns; - -error: - assert(PyErr_Occurred() - || (session != NULL && session->error_override != NULL)); - _sharedns_free(ns); - return NULL; + // One or more items may have interpreter-specific data. + // Currently the xidata for each value is dynamically allocated, + // so technically we don't need to worry about that. + // However, explicitly adding a pending call here is simpler. + (void)_Py_CallInInterpreter(interp, _sharedns_free_pending, ns); } -int -_PyXI_ApplyNamespace(_PyXI_namespace *ns, PyObject *nsobj, PyObject *dflt) +static int +_apply_sharedns(_PyXI_namespace *ns, PyObject *nsobj, PyObject *dflt) { - for (Py_ssize_t i=0; i < ns->len; i++) { + for (Py_ssize_t i=0; i < ns->maxitems; i++) { if (_sharednsitem_apply(&ns->items[i], nsobj, dflt) != 0) { return -1; } @@ -2168,9 +2447,69 @@ _PyXI_ApplyNamespace(_PyXI_namespace *ns, PyObject *nsobj, PyObject *dflt) } -/**********************/ -/* high-level helpers */ -/**********************/ +/*********************************/ +/* switched-interpreter sessions */ +/*********************************/ + +struct xi_session { +#define SESSION_UNUSED 0 +#define SESSION_ACTIVE 1 + int status; + int switched; + + // Once a session has been entered, this is the tstate that was + // current before the session. If it is different from cur_tstate + // then we must have switched interpreters. Either way, this will + // be the current tstate once we exit the session. + PyThreadState *prev_tstate; + // Once a session has been entered, this is the current tstate. + // It must be current when the session exits. + PyThreadState *init_tstate; + // This is true if init_tstate needs cleanup during exit. + int own_init_tstate; + + // This is true if, while entering the session, init_thread took + // "ownership" of the interpreter's __main__ module. This means + // it is the only thread that is allowed to run code there. + // (Caveat: for now, users may still run exec() against the + // __main__ module's dict, though that isn't advisable.) + int running; + // This is a cached reference to the __dict__ of the entered + // interpreter's __main__ module. It is looked up when at the + // beginning of the session as a convenience. + PyObject *main_ns; + + // This is a dict of objects that will be available (via sharing) + // once the session exits. Do not access this directly; use + // _PyXI_Preserve() and _PyXI_GetPreserved() instead; + PyObject *_preserved; +}; + +_PyXI_session * +_PyXI_NewSession(void) +{ + _PyXI_session *session = PyMem_RawCalloc(1, sizeof(_PyXI_session)); + if (session == NULL) { + PyErr_NoMemory(); + return NULL; + } + return session; +} + +void +_PyXI_FreeSession(_PyXI_session *session) +{ + assert(session->status == SESSION_UNUSED); + PyMem_RawFree(session); +} + + +static inline int +_session_is_active(_PyXI_session *session) +{ + return session->status == SESSION_ACTIVE; +} + /* enter/exit a cross-interpreter session */ @@ -2178,29 +2517,33 @@ static void _enter_session(_PyXI_session *session, PyInterpreterState *interp) { // Set here and cleared in _exit_session(). + assert(session->status == SESSION_UNUSED); assert(!session->own_init_tstate); assert(session->init_tstate == NULL); assert(session->prev_tstate == NULL); // Set elsewhere and cleared in _exit_session(). assert(!session->running); assert(session->main_ns == NULL); - // Set elsewhere and cleared in _capture_current_exception(). - assert(session->error_override == NULL); - // Set elsewhere and cleared in _PyXI_ApplyCapturedException(). - assert(session->error == NULL); // Switch to interpreter. PyThreadState *tstate = PyThreadState_Get(); PyThreadState *prev = tstate; - if (interp != tstate->interp) { + int same_interp = (interp == tstate->interp); + if (!same_interp) { tstate = _PyThreadState_NewBound(interp, _PyThreadState_WHENCE_EXEC); // XXX Possible GILState issues? - session->prev_tstate = PyThreadState_Swap(tstate); - assert(session->prev_tstate == prev); - session->own_init_tstate = 1; + PyThreadState *swapped = PyThreadState_Swap(tstate); + assert(swapped == prev); + (void)swapped; } - session->init_tstate = tstate; - session->prev_tstate = prev; + + *session = (_PyXI_session){ + .status = SESSION_ACTIVE, + .switched = !same_interp, + .init_tstate = tstate, + .prev_tstate = prev, + .own_init_tstate = !same_interp, + }; } static void @@ -2209,16 +2552,16 @@ _exit_session(_PyXI_session *session) PyThreadState *tstate = session->init_tstate; assert(tstate != NULL); assert(PyThreadState_Get() == tstate); + assert(!_PyErr_Occurred(tstate)); // Release any of the entered interpreters resources. - if (session->main_ns != NULL) { - Py_CLEAR(session->main_ns); - } + Py_CLEAR(session->main_ns); + Py_CLEAR(session->_preserved); // Ensure this thread no longer owns __main__. if (session->running) { _PyInterpreterState_SetNotRunningMain(tstate->interp); - assert(!PyErr_Occurred()); + assert(!_PyErr_Occurred(tstate)); session->running = 0; } @@ -2234,25 +2577,15 @@ _exit_session(_PyXI_session *session) else { assert(!session->own_init_tstate); } - session->prev_tstate = NULL; - session->init_tstate = NULL; -} -#ifndef NDEBUG -static int -_session_is_active(_PyXI_session *session) -{ - return (session->init_tstate != NULL); + *session = (_PyXI_session){0}; } -#endif static void -_propagate_not_shareable_error(_PyXI_session *session) +_propagate_not_shareable_error(PyThreadState *tstate, + _PyXI_failure *override) { - if (session == NULL) { - return; - } - PyThreadState *tstate = PyThreadState_Get(); + assert(override != NULL); PyObject *exctype = get_notshareableerror_type(tstate); if (exctype == NULL) { PyErr_FormatUnraisable( @@ -2261,166 +2594,463 @@ _propagate_not_shareable_error(_PyXI_session *session) } if (PyErr_ExceptionMatches(exctype)) { // We want to propagate the exception directly. - session->_error_override = _PyXI_ERR_NOT_SHAREABLE; - session->error_override = &session->_error_override; + *override = (_PyXI_failure){ + .code = _PyXI_ERR_NOT_SHAREABLE, + }; } } -static void -_capture_current_exception(_PyXI_session *session) + +static int _ensure_main_ns(_PyXI_session *, _PyXI_failure *); +static const char * capture_session_error(_PyXI_session *, _PyXI_error *, + _PyXI_failure *); + +int +_PyXI_Enter(_PyXI_session *session, + PyInterpreterState *interp, PyObject *nsupdates, + _PyXI_session_result *result) { - assert(session->error == NULL); - if (!PyErr_Occurred()) { - assert(session->error_override == NULL); - return; +#ifndef NDEBUG + PyThreadState *tstate = _PyThreadState_GET(); // Only used for asserts +#endif + + // Convert the attrs for cross-interpreter use. + _PyXI_namespace *sharedns = NULL; + if (nsupdates != NULL) { + assert(PyDict_Check(nsupdates)); + Py_ssize_t len = PyDict_Size(nsupdates); + if (len < 0) { + if (result != NULL) { + result->errcode = _PyXI_ERR_APPLY_NS_FAILURE; + } + return -1; + } + if (len > 0) { + sharedns = _create_sharedns(nsupdates); + if (sharedns == NULL) { + if (result != NULL) { + result->errcode = _PyXI_ERR_APPLY_NS_FAILURE; + } + return -1; + } + // For now we limit it to shareable objects. + xidata_fallback_t fallback = _PyXIDATA_XIDATA_ONLY; + _PyXI_failure _err = XI_FAILURE_INIT; + if (_fill_sharedns(sharedns, nsupdates, fallback, &_err) < 0) { + assert(_PyErr_Occurred(tstate)); + if (_err.code == _PyXI_ERR_NO_ERROR) { + _err.code = _PyXI_ERR_UNCAUGHT_EXCEPTION; + } + _destroy_sharedns(sharedns); + if (result != NULL) { + assert(_err.msg == NULL); + result->errcode = _err.code; + } + return -1; + } + } } - // Handle the exception override. - _PyXI_errcode *override = session->error_override; - session->error_override = NULL; - _PyXI_errcode errcode = override != NULL - ? *override - : _PyXI_ERR_UNCAUGHT_EXCEPTION; + // Switch to the requested interpreter (if necessary). + _enter_session(session, interp); + _PyXI_failure override = XI_FAILURE_INIT; + override.code = _PyXI_ERR_UNCAUGHT_EXCEPTION; +#ifndef NDEBUG + tstate = _PyThreadState_GET(); +#endif - // Pop the exception object. - PyObject *excval = NULL; - if (errcode == _PyXI_ERR_UNCAUGHT_EXCEPTION) { - // We want to actually capture the current exception. - excval = PyErr_GetRaisedException(); + // Ensure this thread owns __main__. + if (_PyInterpreterState_SetRunningMain(interp) < 0) { + // In the case where we didn't switch interpreters, it would + // be more efficient to leave the exception in place and return + // immediately. However, life is simpler if we don't. + override.code = _PyXI_ERR_ALREADY_RUNNING; + goto error; } - else if (errcode == _PyXI_ERR_ALREADY_RUNNING) { - // We don't need the exception info. - PyErr_Clear(); + session->running = 1; + + // Apply the cross-interpreter data. + if (sharedns != NULL) { + if (_ensure_main_ns(session, &override) < 0) { + goto error; + } + if (_apply_sharedns(sharedns, session->main_ns, NULL) < 0) { + override.code = _PyXI_ERR_APPLY_NS_FAILURE; + goto error; + } + _destroy_sharedns(sharedns); } - else { - // We could do a variety of things here, depending on errcode. - // However, for now we simply capture the exception and save - // the errcode. - excval = PyErr_GetRaisedException(); + + override.code = _PyXI_ERR_NO_ERROR; + assert(!_PyErr_Occurred(tstate)); + return 0; + +error: + // We want to propagate all exceptions here directly (best effort). + assert(override.code != _PyXI_ERR_NO_ERROR); + _PyXI_error err = {0}; + const char *failure = capture_session_error(session, &err, &override); + + // Exit the session. + _exit_session(session); +#ifndef NDEBUG + tstate = _PyThreadState_GET(); +#endif + + if (sharedns != NULL) { + _destroy_sharedns(sharedns); } - // Capture the exception. - _PyXI_error *err = &session->_error; - *err = (_PyXI_error){ - .interp = session->init_tstate->interp, - }; - const char *failure; - if (excval == NULL) { - failure = _PyXI_InitError(err, NULL, errcode); + // Apply the error from the other interpreter. + PyObject *excinfo = _PyXI_ApplyError(&err, failure); + xi_error_clear(&err); + if (excinfo != NULL) { + if (result != NULL) { + result->excinfo = excinfo; + } + else { +#ifdef Py_DEBUG + fprintf(stderr, "_PyXI_Enter(): uncaught exception discarded"); +#endif + Py_DECREF(excinfo); + } + } + assert(_PyErr_Occurred(tstate)); + + return -1; +} + +static int _pop_preserved(_PyXI_session *, _PyXI_namespace **, PyObject **, + _PyXI_failure *); +static int _finish_preserved(_PyXI_namespace *, PyObject **); + +int +_PyXI_Exit(_PyXI_session *session, _PyXI_failure *override, + _PyXI_session_result *result) +{ + PyThreadState *tstate = _PyThreadState_GET(); + int res = 0; + + // Capture the raised exception, if any. + _PyXI_error err = {0}; + const char *failure = NULL; + if (override != NULL && override->code == _PyXI_ERR_NO_ERROR) { + assert(override->msg == NULL); + override = NULL; + } + if (_PyErr_Occurred(tstate)) { + failure = capture_session_error(session, &err, override); } else { - failure = _PyXI_InitError(err, excval, _PyXI_ERR_UNCAUGHT_EXCEPTION); - Py_DECREF(excval); - if (failure == NULL && override != NULL) { - err->code = errcode; - } + assert(override == NULL); } - // Handle capture failure. - if (failure != NULL) { - // XXX Make this error message more generic. - fprintf(stderr, - "RunFailedError: script raised an uncaught exception (%s)", - failure); - err = NULL; + // Capture the preserved namespace. + _PyXI_namespace *preserved = NULL; + PyObject *preservedobj = NULL; + if (result != NULL) { + assert(!_PyErr_Occurred(tstate)); + _PyXI_failure _override = XI_FAILURE_INIT; + if (_pop_preserved( + session, &preserved, &preservedobj, &_override) < 0) + { + assert(preserved == NULL); + assert(preservedobj == NULL); + if (xi_error_is_set(&err)) { + // XXX Chain the exception (i.e. set __context__)? + PyErr_FormatUnraisable( + "Exception ignored while capturing preserved objects"); + clear_xi_failure(&_override); + } + else { + if (_override.code == _PyXI_ERR_NO_ERROR) { + _override.code = _PyXI_ERR_UNCAUGHT_EXCEPTION; + } + failure = capture_session_error(session, &err, &_override); + } + } } - // Finished! - assert(!PyErr_Occurred()); - session->error = err; -} + // Exit the session. + assert(!_PyErr_Occurred(tstate)); + _exit_session(session); + tstate = _PyThreadState_GET(); + + // Restore the preserved namespace. + assert(preserved == NULL || preservedobj == NULL); + if (_finish_preserved(preserved, &preservedobj) < 0) { + assert(preservedobj == NULL); + if (xi_error_is_set(&err)) { + // XXX Chain the exception (i.e. set __context__)? + PyErr_FormatUnraisable( + "Exception ignored while capturing preserved objects"); + } + else { + xi_error_set_override_code( + tstate, &err, _PyXI_ERR_PRESERVE_FAILURE); + _propagate_not_shareable_error(tstate, err.override); + } + } + if (result != NULL) { + result->preserved = preservedobj; + result->errcode = err.override != NULL + ? err.override->code + : _PyXI_ERR_NO_ERROR; + } -PyObject * -_PyXI_ApplyCapturedException(_PyXI_session *session) -{ - assert(!PyErr_Occurred()); - assert(session->error != NULL); - PyObject *res = _PyXI_ApplyError(session->error); - assert((res == NULL) != (PyErr_Occurred() == NULL)); - session->error = NULL; + // Apply the error from the other interpreter, if any. + if (xi_error_is_set(&err)) { + res = -1; + assert(!_PyErr_Occurred(tstate)); + PyObject *excinfo = _PyXI_ApplyError(&err, failure); + if (excinfo == NULL) { + assert(_PyErr_Occurred(tstate)); + if (result != NULL && !xi_error_has_override(&err)) { + _PyXI_ClearResult(result); + *result = (_PyXI_session_result){ + .errcode = _PyXI_ERR_EXC_PROPAGATION_FAILURE, + }; + } + } + else if (result != NULL) { + result->excinfo = excinfo; + } + else { +#ifdef Py_DEBUG + fprintf(stderr, "_PyXI_Exit(): uncaught exception discarded"); +#endif + Py_DECREF(excinfo); + } + xi_error_clear(&err); + } return res; } -int -_PyXI_HasCapturedException(_PyXI_session *session) -{ - return session->error != NULL; -} -int -_PyXI_Enter(_PyXI_session *session, - PyInterpreterState *interp, PyObject *nsupdates) +/* in an active cross-interpreter session */ + +static const char * +capture_session_error(_PyXI_session *session, _PyXI_error *err, + _PyXI_failure *override) { - // Convert the attrs for cross-interpreter use. - _PyXI_namespace *sharedns = NULL; - if (nsupdates != NULL) { - sharedns = _PyXI_NamespaceFromDict(nsupdates, NULL); - if (sharedns == NULL && PyErr_Occurred()) { - assert(session->error == NULL); - return -1; + assert(_session_is_active(session)); + assert(!xi_error_is_set(err)); + PyThreadState *tstate = session->init_tstate; + + // Normalize the exception override. + if (override != NULL) { + if (override->code == _PyXI_ERR_UNCAUGHT_EXCEPTION) { + assert(override->msg == NULL); + override = NULL; + } + else { + assert(override->code != _PyXI_ERR_NO_ERROR); } } - // Switch to the requested interpreter (if necessary). - _enter_session(session, interp); - PyThreadState *session_tstate = session->init_tstate; - _PyXI_errcode errcode = _PyXI_ERR_UNCAUGHT_EXCEPTION; + // Handle the exception, if any. + const char *failure = NULL; + PyObject *exc = xi_error_resolve_current_exc(tstate, override); + if (exc != NULL) { + // There is an unhandled exception we need to preserve. + failure = xi_error_set_exc(tstate, err, exc); + Py_DECREF(exc); + if (_PyErr_Occurred(tstate)) { + PyErr_FormatUnraisable(failure); + } + } - // Ensure this thread owns __main__. - if (_PyInterpreterState_SetRunningMain(interp) < 0) { - // In the case where we didn't switch interpreters, it would - // be more efficient to leave the exception in place and return - // immediately. However, life is simpler if we don't. - errcode = _PyXI_ERR_ALREADY_RUNNING; - goto error; + // Handle the override. + if (override != NULL && failure == NULL) { + xi_error_set_override(tstate, err, override); } - session->running = 1; + // Finished! + assert(!_PyErr_Occurred(tstate)); + return failure; +} + +static int +_ensure_main_ns(_PyXI_session *session, _PyXI_failure *failure) +{ + assert(_session_is_active(session)); + PyThreadState *tstate = session->init_tstate; + if (session->main_ns != NULL) { + return 0; + } // Cache __main__.__dict__. - PyObject *main_mod = _Py_GetMainModule(session_tstate); + PyObject *main_mod = _Py_GetMainModule(tstate); if (_Py_CheckMainModule(main_mod) < 0) { - errcode = _PyXI_ERR_MAIN_NS_FAILURE; - goto error; + Py_XDECREF(main_mod); + if (failure != NULL) { + *failure = (_PyXI_failure){ + .code = _PyXI_ERR_MAIN_NS_FAILURE, + }; + } + return -1; } PyObject *ns = PyModule_GetDict(main_mod); // borrowed Py_DECREF(main_mod); if (ns == NULL) { - errcode = _PyXI_ERR_MAIN_NS_FAILURE; - goto error; + if (failure != NULL) { + *failure = (_PyXI_failure){ + .code = _PyXI_ERR_MAIN_NS_FAILURE, + }; + } + return -1; } session->main_ns = Py_NewRef(ns); + return 0; +} - // Apply the cross-interpreter data. - if (sharedns != NULL) { - if (_PyXI_ApplyNamespace(sharedns, ns, NULL) < 0) { - errcode = _PyXI_ERR_APPLY_NS_FAILURE; +PyObject * +_PyXI_GetMainNamespace(_PyXI_session *session, _PyXI_failure *failure) +{ + if (!_session_is_active(session)) { + PyErr_SetString(PyExc_RuntimeError, "session not active"); + return NULL; + } + if (_ensure_main_ns(session, failure) < 0) { + return NULL; + } + return session->main_ns; +} + + +static int +_pop_preserved(_PyXI_session *session, + _PyXI_namespace **p_xidata, PyObject **p_obj, + _PyXI_failure *p_failure) +{ + _PyXI_failure failure = XI_FAILURE_INIT; + _PyXI_namespace *xidata = NULL; + assert(_PyThreadState_GET() == session->init_tstate); // active session + + if (session->_preserved == NULL) { + *p_xidata = NULL; + *p_obj = NULL; + return 0; + } + if (session->init_tstate == session->prev_tstate) { + // We did not switch interpreters. + *p_xidata = NULL; + *p_obj = session->_preserved; + session->_preserved = NULL; + return 0; + } + *p_obj = NULL; + + // We did switch interpreters. + Py_ssize_t len = PyDict_Size(session->_preserved); + if (len < 0) { + failure.code = _PyXI_ERR_PRESERVE_FAILURE; + goto error; + } + else if (len == 0) { + *p_xidata = NULL; + } + else { + _PyXI_namespace *xidata = _create_sharedns(session->_preserved); + if (xidata == NULL) { + failure.code = _PyXI_ERR_PRESERVE_FAILURE; goto error; } - _PyXI_FreeNamespace(sharedns); + if (_fill_sharedns(xidata, session->_preserved, + _PyXIDATA_FULL_FALLBACK, &failure) < 0) + { + if (failure.code != _PyXI_ERR_NOT_SHAREABLE) { + assert(failure.msg != NULL); + failure.code = _PyXI_ERR_PRESERVE_FAILURE; + } + goto error; + } + *p_xidata = xidata; } + Py_CLEAR(session->_preserved); + return 0; - errcode = _PyXI_ERR_NO_ERROR; - assert(!PyErr_Occurred()); +error: + if (p_failure != NULL) { + *p_failure = failure; + } + if (xidata != NULL) { + _destroy_sharedns(xidata); + } + return -1; +} + +static int +_finish_preserved(_PyXI_namespace *xidata, PyObject **p_preserved) +{ + if (xidata == NULL) { + return 0; + } + int res = -1; + if (p_preserved != NULL) { + PyObject *ns = PyDict_New(); + if (ns == NULL) { + goto finally; + } + if (_apply_sharedns(xidata, ns, NULL) < 0) { + Py_CLEAR(ns); + goto finally; + } + *p_preserved = ns; + } + res = 0; + +finally: + _destroy_sharedns(xidata); + return res; +} + +int +_PyXI_Preserve(_PyXI_session *session, const char *name, PyObject *value, + _PyXI_failure *p_failure) +{ + _PyXI_failure failure = XI_FAILURE_INIT; + if (!_session_is_active(session)) { + PyErr_SetString(PyExc_RuntimeError, "session not active"); + return -1; + } + if (session->_preserved == NULL) { + session->_preserved = PyDict_New(); + if (session->_preserved == NULL) { + set_exc_with_cause(PyExc_RuntimeError, + "failed to initialize preserved objects"); + failure.code = _PyXI_ERR_PRESERVE_FAILURE; + goto error; + } + } + if (PyDict_SetItemString(session->_preserved, name, value) < 0) { + set_exc_with_cause(PyExc_RuntimeError, "failed to preserve object"); + failure.code = _PyXI_ERR_PRESERVE_FAILURE; + goto error; + } return 0; error: - assert(PyErr_Occurred()); - // We want to propagate all exceptions here directly (best effort). - assert(errcode != _PyXI_ERR_UNCAUGHT_EXCEPTION); - session->error_override = &errcode; - _capture_current_exception(session); - _exit_session(session); - if (sharedns != NULL) { - _PyXI_FreeNamespace(sharedns); + if (p_failure != NULL) { + *p_failure = failure; } return -1; } +PyObject * +_PyXI_GetPreserved(_PyXI_session_result *result, const char *name) +{ + PyObject *value = NULL; + if (result->preserved != NULL) { + (void)PyDict_GetItemStringRef(result->preserved, name, &value); + } + return value; +} + void -_PyXI_Exit(_PyXI_session *session) +_PyXI_ClearResult(_PyXI_session_result *result) { - _capture_current_exception(session); - _exit_session(session); + Py_CLEAR(result->preserved); + Py_CLEAR(result->excinfo); } |