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/* Execute compiled code */
/* XXX TO DO:
XXX speed up searching for keywords by using a dictionary
XXX document it!
*/
#include "Python.h"
#include "compile.h"
#include "frameobject.h"
#include "eval.h"
#include "opcode.h"
#include "structmember.h"
#include <ctype.h>
/* Turn this on if your compiler chokes on the big switch: */
/* #define CASE_TOO_BIG 1 */
#ifdef Py_DEBUG
/* For debugging the interpreter: */
#define LLTRACE 1 /* Low-level trace feature */
#define CHECKEXC 1 /* Double-check exception checking */
#endif
typedef PyObject *(*callproc)(PyObject *, PyObject *, PyObject *);
/* Forward declarations */
static PyObject *eval_frame(PyFrameObject *);
static PyObject *call_function(PyObject ***, int);
static PyObject *fast_function(PyObject *, PyObject ***, int, int, int);
static PyObject *do_call(PyObject *, PyObject ***, int, int);
static PyObject *ext_do_call(PyObject *, PyObject ***, int, int, int);
static PyObject *update_keyword_args(PyObject *, int, PyObject ***,PyObject *);
static PyObject *update_star_args(int, int, PyObject *, PyObject ***);
static PyObject *load_args(PyObject ***, int);
#define CALL_FLAG_VAR 1
#define CALL_FLAG_KW 2
#ifdef LLTRACE
static int prtrace(PyObject *, char *);
#endif
static int call_trace(Py_tracefunc, PyObject *, PyFrameObject *,
int, PyObject *);
static void call_trace_protected(Py_tracefunc, PyObject *,
PyFrameObject *, int);
static void call_exc_trace(Py_tracefunc, PyObject *, PyFrameObject *);
static int maybe_call_line_trace(Py_tracefunc, PyObject *,
PyFrameObject *, int *, int *, int *);
static PyObject *apply_slice(PyObject *, PyObject *, PyObject *);
static int assign_slice(PyObject *, PyObject *,
PyObject *, PyObject *);
static PyObject *cmp_outcome(int, PyObject *, PyObject *);
static PyObject *import_from(PyObject *, PyObject *);
static int import_all_from(PyObject *, PyObject *);
static PyObject *build_class(PyObject *, PyObject *, PyObject *);
static int exec_statement(PyFrameObject *,
PyObject *, PyObject *, PyObject *);
static void set_exc_info(PyThreadState *, PyObject *, PyObject *, PyObject *);
static void reset_exc_info(PyThreadState *);
static void format_exc_check_arg(PyObject *, char *, PyObject *);
#define NAME_ERROR_MSG \
"name '%.200s' is not defined"
#define GLOBAL_NAME_ERROR_MSG \
"global name '%.200s' is not defined"
#define UNBOUNDLOCAL_ERROR_MSG \
"local variable '%.200s' referenced before assignment"
#define UNBOUNDFREE_ERROR_MSG \
"free variable '%.200s' referenced before assignment" \
" in enclosing scope"
/* Dynamic execution profile */
#ifdef DYNAMIC_EXECUTION_PROFILE
#ifdef DXPAIRS
static long dxpairs[257][256];
#define dxp dxpairs[256]
#else
static long dxp[256];
#endif
#endif
/* Function call profile */
#ifdef CALL_PROFILE
#define PCALL_NUM 11
static int pcall[PCALL_NUM];
#define PCALL_ALL 0
#define PCALL_FUNCTION 1
#define PCALL_FAST_FUNCTION 2
#define PCALL_FASTER_FUNCTION 3
#define PCALL_METHOD 4
#define PCALL_BOUND_METHOD 5
#define PCALL_CFUNCTION 6
#define PCALL_TYPE 7
#define PCALL_GENERATOR 8
#define PCALL_OTHER 9
#define PCALL_POP 10
/* Notes about the statistics
PCALL_FAST stats
FAST_FUNCTION means no argument tuple needs to be created.
FASTER_FUNCTION means that the fast-path frame setup code is used.
If there is a method call where the call can be optimized by changing
the argument tuple and calling the function directly, it gets recorded
twice.
As a result, the relationship among the statistics appears to be
PCALL_ALL == PCALL_FUNCTION + PCALL_METHOD - PCALL_BOUND_METHOD +
PCALL_CFUNCTION + PCALL_TYPE + PCALL_GENERATOR + PCALL_OTHER
PCALL_FUNCTION > PCALL_FAST_FUNCTION > PCALL_FASTER_FUNCTION
PCALL_METHOD > PCALL_BOUND_METHOD
*/
#define PCALL(POS) pcall[POS]++
PyObject *
PyEval_GetCallStats(PyObject *self)
{
return Py_BuildValue("iiiiiiiiii",
pcall[0], pcall[1], pcall[2], pcall[3],
pcall[4], pcall[5], pcall[6], pcall[7],
pcall[8], pcall[9]);
}
#else
#define PCALL(O)
PyObject *
PyEval_GetCallStats(PyObject *self)
{
Py_INCREF(Py_None);
return Py_None;
}
#endif
static PyTypeObject gentype;
typedef struct {
PyObject_HEAD
/* The gi_ prefix is intended to remind of generator-iterator. */
PyFrameObject *gi_frame;
/* True if generator is being executed. */
int gi_running;
/* List of weak reference. */
PyObject *gi_weakreflist;
} genobject;
static PyObject *
gen_new(PyFrameObject *f)
{
genobject *gen = PyObject_GC_New(genobject, &gentype);
if (gen == NULL) {
Py_DECREF(f);
return NULL;
}
gen->gi_frame = f;
gen->gi_running = 0;
gen->gi_weakreflist = NULL;
_PyObject_GC_TRACK(gen);
return (PyObject *)gen;
}
static int
gen_traverse(genobject *gen, visitproc visit, void *arg)
{
return visit((PyObject *)gen->gi_frame, arg);
}
static void
gen_dealloc(genobject *gen)
{
_PyObject_GC_UNTRACK(gen);
if (gen->gi_weakreflist != NULL)
PyObject_ClearWeakRefs((PyObject *) gen);
Py_DECREF(gen->gi_frame);
PyObject_GC_Del(gen);
}
static PyObject *
gen_iternext(genobject *gen)
{
PyThreadState *tstate = PyThreadState_GET();
PyFrameObject *f = gen->gi_frame;
PyObject *result;
if (gen->gi_running) {
PyErr_SetString(PyExc_ValueError,
"generator already executing");
return NULL;
}
if (f->f_stacktop == NULL)
return NULL;
/* Generators always return to their most recent caller, not
* necessarily their creator. */
Py_XINCREF(tstate->frame);
assert(f->f_back == NULL);
f->f_back = tstate->frame;
gen->gi_running = 1;
result = eval_frame(f);
gen->gi_running = 0;
/* Don't keep the reference to f_back any longer than necessary. It
* may keep a chain of frames alive or it could create a reference
* cycle. */
Py_XDECREF(f->f_back);
f->f_back = NULL;
/* If the generator just returned (as opposed to yielding), signal
* that the generator is exhausted. */
if (result == Py_None && f->f_stacktop == NULL) {
Py_DECREF(result);
result = NULL;
}
return result;
}
static PyObject *
gen_getiter(PyObject *gen)
{
Py_INCREF(gen);
return gen;
}
static PyMemberDef gen_memberlist[] = {
{"gi_frame", T_OBJECT, offsetof(genobject, gi_frame), RO},
{"gi_running", T_INT, offsetof(genobject, gi_running), RO},
{NULL} /* Sentinel */
};
static PyTypeObject gentype = {
PyObject_HEAD_INIT(&PyType_Type)
0, /* ob_size */
"generator", /* tp_name */
sizeof(genobject), /* tp_basicsize */
0, /* tp_itemsize */
/* methods */
(destructor)gen_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
0, /* tp_doc */
(traverseproc)gen_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
offsetof(genobject, gi_weakreflist), /* tp_weaklistoffset */
(getiterfunc)gen_getiter, /* tp_iter */
(iternextfunc)gen_iternext, /* tp_iternext */
0, /* tp_methods */
gen_memberlist, /* tp_members */
0, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
};
#ifdef WITH_THREAD
#ifndef DONT_HAVE_ERRNO_H
#include <errno.h>
#endif
#include "pythread.h"
extern int _PyThread_Started; /* Flag for Py_Exit */
static PyThread_type_lock interpreter_lock = 0; /* This is the GIL */
static long main_thread = 0;
void
PyEval_InitThreads(void)
{
if (interpreter_lock)
return;
_PyThread_Started = 1;
interpreter_lock = PyThread_allocate_lock();
PyThread_acquire_lock(interpreter_lock, 1);
main_thread = PyThread_get_thread_ident();
}
void
PyEval_AcquireLock(void)
{
PyThread_acquire_lock(interpreter_lock, 1);
}
void
PyEval_ReleaseLock(void)
{
PyThread_release_lock(interpreter_lock);
}
void
PyEval_AcquireThread(PyThreadState *tstate)
{
if (tstate == NULL)
Py_FatalError("PyEval_AcquireThread: NULL new thread state");
/* Check someone has called PyEval_InitThreads() to create the lock */
assert(interpreter_lock);
PyThread_acquire_lock(interpreter_lock, 1);
if (PyThreadState_Swap(tstate) != NULL)
Py_FatalError(
"PyEval_AcquireThread: non-NULL old thread state");
}
void
PyEval_ReleaseThread(PyThreadState *tstate)
{
if (tstate == NULL)
Py_FatalError("PyEval_ReleaseThread: NULL thread state");
if (PyThreadState_Swap(NULL) != tstate)
Py_FatalError("PyEval_ReleaseThread: wrong thread state");
PyThread_release_lock(interpreter_lock);
}
/* This function is called from PyOS_AfterFork to ensure that newly
created child processes don't hold locks referring to threads which
are not running in the child process. (This could also be done using
pthread_atfork mechanism, at least for the pthreads implementation.) */
void
PyEval_ReInitThreads(void)
{
if (!interpreter_lock)
return;
/*XXX Can't use PyThread_free_lock here because it does too
much error-checking. Doing this cleanly would require
adding a new function to each thread_*.h. Instead, just
create a new lock and waste a little bit of memory */
interpreter_lock = PyThread_allocate_lock();
PyThread_acquire_lock(interpreter_lock, 1);
main_thread = PyThread_get_thread_ident();
}
#endif
/* Functions save_thread and restore_thread are always defined so
dynamically loaded modules needn't be compiled separately for use
with and without threads: */
PyThreadState *
PyEval_SaveThread(void)
{
PyThreadState *tstate = PyThreadState_Swap(NULL);
if (tstate == NULL)
Py_FatalError("PyEval_SaveThread: NULL tstate");
#ifdef WITH_THREAD
if (interpreter_lock)
PyThread_release_lock(interpreter_lock);
#endif
return tstate;
}
void
PyEval_RestoreThread(PyThreadState *tstate)
{
if (tstate == NULL)
Py_FatalError("PyEval_RestoreThread: NULL tstate");
#ifdef WITH_THREAD
if (interpreter_lock) {
int err = errno;
PyThread_acquire_lock(interpreter_lock, 1);
errno = err;
}
#endif
PyThreadState_Swap(tstate);
}
/* Mechanism whereby asynchronously executing callbacks (e.g. UNIX
signal handlers or Mac I/O completion routines) can schedule calls
to a function to be called synchronously.
The synchronous function is called with one void* argument.
It should return 0 for success or -1 for failure -- failure should
be accompanied by an exception.
If registry succeeds, the registry function returns 0; if it fails
(e.g. due to too many pending calls) it returns -1 (without setting
an exception condition).
Note that because registry may occur from within signal handlers,
or other asynchronous events, calling malloc() is unsafe!
#ifdef WITH_THREAD
Any thread can schedule pending calls, but only the main thread
will execute them.
#endif
XXX WARNING! ASYNCHRONOUSLY EXECUTING CODE!
There are two possible race conditions:
(1) nested asynchronous registry calls;
(2) registry calls made while pending calls are being processed.
While (1) is very unlikely, (2) is a real possibility.
The current code is safe against (2), but not against (1).
The safety against (2) is derived from the fact that only one
thread (the main thread) ever takes things out of the queue.
XXX Darn! With the advent of thread state, we should have an array
of pending calls per thread in the thread state! Later...
*/
#define NPENDINGCALLS 32
static struct {
int (*func)(void *);
void *arg;
} pendingcalls[NPENDINGCALLS];
static volatile int pendingfirst = 0;
static volatile int pendinglast = 0;
static volatile int things_to_do = 0;
int
Py_AddPendingCall(int (*func)(void *), void *arg)
{
static int busy = 0;
int i, j;
/* XXX Begin critical section */
/* XXX If you want this to be safe against nested
XXX asynchronous calls, you'll have to work harder! */
if (busy)
return -1;
busy = 1;
i = pendinglast;
j = (i + 1) % NPENDINGCALLS;
if (j == pendingfirst) {
busy = 0;
return -1; /* Queue full */
}
pendingcalls[i].func = func;
pendingcalls[i].arg = arg;
pendinglast = j;
_Py_Ticker = 0;
things_to_do = 1; /* Signal main loop */
busy = 0;
/* XXX End critical section */
return 0;
}
int
Py_MakePendingCalls(void)
{
static int busy = 0;
#ifdef WITH_THREAD
if (main_thread && PyThread_get_thread_ident() != main_thread)
return 0;
#endif
if (busy)
return 0;
busy = 1;
things_to_do = 0;
for (;;) {
int i;
int (*func)(void *);
void *arg;
i = pendingfirst;
if (i == pendinglast)
break; /* Queue empty */
func = pendingcalls[i].func;
arg = pendingcalls[i].arg;
pendingfirst = (i + 1) % NPENDINGCALLS;
if (func(arg) < 0) {
busy = 0;
things_to_do = 1; /* We're not done yet */
return -1;
}
}
busy = 0;
return 0;
}
/* The interpreter's recursion limit */
static int recursion_limit = 1000;
int _Py_CheckRecursionLimit = 1000;
int
Py_GetRecursionLimit(void)
{
return recursion_limit;
}
void
Py_SetRecursionLimit(int new_limit)
{
recursion_limit = new_limit;
_Py_CheckRecursionLimit = recursion_limit;
}
/* the macro Py_EnterRecursiveCall() only calls _Py_CheckRecursiveCall()
if the recursion_depth reaches _Py_CheckRecursionLimit.
If USE_STACKCHECK, the macro decrements _Py_CheckRecursionLimit
to guarantee that _Py_CheckRecursiveCall() is regularly called.
Without USE_STACKCHECK, there is no need for this. */
int
_Py_CheckRecursiveCall(char *where)
{
PyThreadState *tstate = PyThreadState_GET();
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
--tstate->recursion_depth;
PyErr_SetString(PyExc_MemoryError, "Stack overflow");
return -1;
}
#endif
if (tstate->recursion_depth > recursion_limit) {
--tstate->recursion_depth;
PyErr_Format(PyExc_RuntimeError,
"maximum recursion depth exceeded%s",
where);
return -1;
}
_Py_CheckRecursionLimit = recursion_limit;
return 0;
}
/* Status code for main loop (reason for stack unwind) */
enum why_code {
WHY_NOT = 0x0001, /* No error */
WHY_EXCEPTION = 0x0002, /* Exception occurred */
WHY_RERAISE = 0x0004, /* Exception re-raised by 'finally' */
WHY_RETURN = 0x0008, /* 'return' statement */
WHY_BREAK = 0x0010, /* 'break' statement */
WHY_CONTINUE = 0x0020, /* 'continue' statement */
WHY_YIELD = 0x0040 /* 'yield' operator */
};
static enum why_code do_raise(PyObject *, PyObject *, PyObject *);
static int unpack_iterable(PyObject *, int, PyObject **);
/* for manipulating the thread switch and periodic "stuff" - used to be
per thread, now just a pair o' globals */
int _Py_CheckInterval = 100;
volatile int _Py_Ticker = 100;
PyObject *
PyEval_EvalCode(PyCodeObject *co, PyObject *globals, PyObject *locals)
{
/* XXX raise SystemError if globals is NULL */
return PyEval_EvalCodeEx(co,
globals, locals,
(PyObject **)NULL, 0,
(PyObject **)NULL, 0,
(PyObject **)NULL, 0,
NULL);
}
/* Interpreter main loop */
static PyObject *
eval_frame(PyFrameObject *f)
{
#ifdef DXPAIRS
int lastopcode = 0;
#endif
PyObject **stack_pointer; /* Next free slot in value stack */
register unsigned char *next_instr;
register int opcode=0; /* Current opcode */
register int oparg=0; /* Current opcode argument, if any */
register enum why_code why; /* Reason for block stack unwind */
register int err; /* Error status -- nonzero if error */
register PyObject *x; /* Result object -- NULL if error */
register PyObject *v; /* Temporary objects popped off stack */
register PyObject *w;
register PyObject *u;
register PyObject *t;
register PyObject *stream = NULL; /* for PRINT opcodes */
register PyObject **fastlocals, **freevars;
PyObject *retval = NULL; /* Return value */
PyThreadState *tstate = PyThreadState_GET();
PyCodeObject *co;
/* when tracing we set things up so that
not (instr_lb <= current_bytecode_offset < instr_ub)
is true when the line being executed has changed. The
initial values are such as to make this false the first
time it is tested. */
int instr_ub = -1, instr_lb = 0, instr_prev = -1;
unsigned char *first_instr;
PyObject *names;
PyObject *consts;
#ifdef LLTRACE
int lltrace;
#endif
#if defined(Py_DEBUG) || defined(LLTRACE)
/* Make it easier to find out where we are with a debugger */
char *filename;
#endif
/* Tuple access macros */
#ifndef Py_DEBUG
#define GETITEM(v, i) PyTuple_GET_ITEM((PyTupleObject *)(v), (i))
#else
#define GETITEM(v, i) PyTuple_GetItem((v), (i))
#endif
/* Code access macros */
#define INSTR_OFFSET() (next_instr - first_instr)
#define NEXTOP() (*next_instr++)
#define OPARG() (next_instr[0] + (next_instr[1]<<8))
#define SKIPARG() (next_instr += 2)
#define JUMPTO(x) (next_instr = first_instr + (x))
#define JUMPBY(x) (next_instr += (x))
/* OpCode prediction macros
Some opcodes tend to come in pairs thus making it possible to predict
the second code when the first is run. For example, COMPARE_OP is often
followed by JUMP_IF_FALSE or JUMP_IF_TRUE. And, those opcodes are often
followed by a POP_TOP.
Verifying the prediction costs a single high-speed test of register
variable against a constant. If the pairing was good, then the
processor has a high likelihood of making its own successful branch
prediction which results in a nearly zero overhead transition to the
next opcode.
A successful prediction saves a trip through the eval-loop including
its two unpredictable branches, the HASARG test and the switch-case.
If collecting opcode statistics, turn off prediction so that
statistics are accurately maintained (the predictions bypass
the opcode frequency counter updates).
*/
#ifdef DYNAMIC_EXECUTION_PROFILE
#define PREDICT(op) if (0) goto PRED_##op
#else
#define PREDICT(op) if (*next_instr == op) goto PRED_##op
#endif
#define PREDICTED(op) PRED_##op: next_instr++
#define PREDICTED_WITH_ARG(op) PRED_##op: oparg = (next_instr[2]<<8) + \
next_instr[1]; next_instr += 3
/* Stack manipulation macros */
#define STACK_LEVEL() (stack_pointer - f->f_valuestack)
#define EMPTY() (STACK_LEVEL() == 0)
#define TOP() (stack_pointer[-1])
#define SECOND() (stack_pointer[-2])
#define THIRD() (stack_pointer[-3])
#define FOURTH() (stack_pointer[-4])
#define SET_TOP(v) (stack_pointer[-1] = (v))
#define SET_SECOND(v) (stack_pointer[-2] = (v))
#define SET_THIRD(v) (stack_pointer[-3] = (v))
#define SET_FOURTH(v) (stack_pointer[-4] = (v))
#define BASIC_STACKADJ(n) (stack_pointer += n)
#define BASIC_PUSH(v) (*stack_pointer++ = (v))
#define BASIC_POP() (*--stack_pointer)
#ifdef LLTRACE
#define PUSH(v) { (void)(BASIC_PUSH(v), \
lltrace && prtrace(TOP(), "push")); \
assert(STACK_LEVEL() <= f->f_stacksize); }
#define POP() ((void)(lltrace && prtrace(TOP(), "pop")), BASIC_POP())
#define STACKADJ(n) { (void)(BASIC_STACKADJ(n), \
lltrace && prtrace(TOP(), "stackadj")); \
assert(STACK_LEVEL() <= f->f_stacksize); }
#else
#define PUSH(v) BASIC_PUSH(v)
#define POP() BASIC_POP()
#define STACKADJ(n) BASIC_STACKADJ(n)
#endif
/* Local variable macros */
#define GETLOCAL(i) (fastlocals[i])
/* The SETLOCAL() macro must not DECREF the local variable in-place and
then store the new value; it must copy the old value to a temporary
value, then store the new value, and then DECREF the temporary value.
This is because it is possible that during the DECREF the frame is
accessed by other code (e.g. a __del__ method or gc.collect()) and the
variable would be pointing to already-freed memory. */
#define SETLOCAL(i, value) do { PyObject *tmp = GETLOCAL(i); \
GETLOCAL(i) = value; \
Py_XDECREF(tmp); } while (0)
/* Start of code */
if (f == NULL)
return NULL;
/* push frame */
if (Py_EnterRecursiveCall(""))
return NULL;
tstate->frame = f;
if (tstate->use_tracing) {
if (tstate->c_tracefunc != NULL) {
/* tstate->c_tracefunc, if defined, is a
function that will be called on *every* entry
to a code block. Its return value, if not
None, is a function that will be called at
the start of each executed line of code.
(Actually, the function must return itself
in order to continue tracing.) The trace
functions are called with three arguments:
a pointer to the current frame, a string
indicating why the function is called, and
an argument which depends on the situation.
The global trace function is also called
whenever an exception is detected. */
if (call_trace(tstate->c_tracefunc, tstate->c_traceobj,
f, PyTrace_CALL, Py_None)) {
/* Trace function raised an error */
goto exit_eval_frame;
}
}
if (tstate->c_profilefunc != NULL) {
/* Similar for c_profilefunc, except it needn't
return itself and isn't called for "line" events */
if (call_trace(tstate->c_profilefunc,
tstate->c_profileobj,
f, PyTrace_CALL, Py_None)) {
/* Profile function raised an error */
goto exit_eval_frame;
}
}
}
co = f->f_code;
names = co->co_names;
consts = co->co_consts;
fastlocals = f->f_localsplus;
freevars = f->f_localsplus + f->f_nlocals;
first_instr = PyString_AS_STRING(co->co_code);
/* An explanation is in order for the next line.
f->f_lasti now refers to the index of the last instruction
executed. You might think this was obvious from the name, but
this wasn't always true before 2.3! PyFrame_New now sets
f->f_lasti to -1 (i.e. the index *before* the first instruction)
and YIELD_VALUE doesn't fiddle with f_lasti any more. So this
does work. Promise. */
next_instr = first_instr + f->f_lasti + 1;
stack_pointer = f->f_stacktop;
assert(stack_pointer != NULL);
f->f_stacktop = NULL; /* remains NULL unless yield suspends frame */
#ifdef LLTRACE
lltrace = PyDict_GetItemString(f->f_globals,"__lltrace__") != NULL;
#endif
#if defined(Py_DEBUG) || defined(LLTRACE)
filename = PyString_AsString(co->co_filename);
#endif
why = WHY_NOT;
err = 0;
x = Py_None; /* Not a reference, just anything non-NULL */
w = NULL;
for (;;) {
assert(stack_pointer >= f->f_valuestack); /* else underflow */
assert(STACK_LEVEL() <= f->f_stacksize); /* else overflow */
/* Do periodic things. Doing this every time through
the loop would add too much overhead, so we do it
only every Nth instruction. We also do it if
``things_to_do'' is set, i.e. when an asynchronous
event needs attention (e.g. a signal handler or
async I/O handler); see Py_AddPendingCall() and
Py_MakePendingCalls() above. */
if (--_Py_Ticker < 0) {
if (*next_instr == SETUP_FINALLY) {
/* Make the last opcode before
a try: finally: block uninterruptable. */
goto fast_next_opcode;
}
_Py_Ticker = _Py_CheckInterval;
tstate->tick_counter++;
if (things_to_do) {
if (Py_MakePendingCalls() < 0) {
why = WHY_EXCEPTION;
goto on_error;
}
}
#ifdef WITH_THREAD
if (interpreter_lock) {
/* Give another thread a chance */
if (PyThreadState_Swap(NULL) != tstate)
Py_FatalError("ceval: tstate mix-up");
PyThread_release_lock(interpreter_lock);
/* Other threads may run now */
PyThread_acquire_lock(interpreter_lock, 1);
if (PyThreadState_Swap(tstate) != NULL)
Py_FatalError("ceval: orphan tstate");
/* Check for thread interrupts */
if (tstate->async_exc != NULL) {
x = tstate->async_exc;
tstate->async_exc = NULL;
PyErr_SetNone(x);
Py_DECREF(x);
why = WHY_EXCEPTION;
goto on_error;
}
}
#endif
}
fast_next_opcode:
f->f_lasti = INSTR_OFFSET();
/* line-by-line tracing support */
if (tstate->c_tracefunc != NULL && !tstate->tracing) {
/* see maybe_call_line_trace
for expository comments */
f->f_stacktop = stack_pointer;
err = maybe_call_line_trace(tstate->c_tracefunc,
tstate->c_traceobj,
f, &instr_lb, &instr_ub,
&instr_prev);
/* Reload possibly changed frame fields */
JUMPTO(f->f_lasti);
if (f->f_stacktop != NULL) {
stack_pointer = f->f_stacktop;
f->f_stacktop = NULL;
}
if (err) {
/* trace function raised an exception */
goto on_error;
}
}
/* Extract opcode and argument */
opcode = NEXTOP();
if (HAS_ARG(opcode)) {
oparg = OPARG();
SKIPARG();
}
dispatch_opcode:
#ifdef DYNAMIC_EXECUTION_PROFILE
#ifdef DXPAIRS
dxpairs[lastopcode][opcode]++;
lastopcode = opcode;
#endif
dxp[opcode]++;
#endif
#ifdef LLTRACE
/* Instruction tracing */
if (lltrace) {
if (HAS_ARG(opcode)) {
printf("%d: %d, %d\n",
f->f_lasti, opcode, oparg);
}
else {
printf("%d: %d\n",
f->f_lasti, opcode);
}
}
#endif
/* Main switch on opcode */
switch (opcode) {
/* BEWARE!
It is essential that any operation that fails sets either
x to NULL, err to nonzero, or why to anything but WHY_NOT,
and that no operation that succeeds does this! */
/* case STOP_CODE: this is an error! */
case LOAD_FAST:
x = GETLOCAL(oparg);
if (x != NULL) {
Py_INCREF(x);
PUSH(x);
goto fast_next_opcode;
}
format_exc_check_arg(PyExc_UnboundLocalError,
UNBOUNDLOCAL_ERROR_MSG,
PyTuple_GetItem(co->co_varnames, oparg));
break;
case LOAD_CONST:
x = GETITEM(consts, oparg);
Py_INCREF(x);
PUSH(x);
goto fast_next_opcode;
PREDICTED_WITH_ARG(STORE_FAST);
case STORE_FAST:
v = POP();
SETLOCAL(oparg, v);
goto fast_next_opcode;
PREDICTED(POP_TOP);
case POP_TOP:
v = POP();
Py_DECREF(v);
goto fast_next_opcode;
case ROT_TWO:
v = TOP();
w = SECOND();
SET_TOP(w);
SET_SECOND(v);
goto fast_next_opcode;
case ROT_THREE:
v = TOP();
w = SECOND();
x = THIRD();
SET_TOP(w);
SET_SECOND(x);
SET_THIRD(v);
goto fast_next_opcode;
case ROT_FOUR:
u = TOP();
v = SECOND();
w = THIRD();
x = FOURTH();
SET_TOP(v);
SET_SECOND(w);
SET_THIRD(x);
SET_FOURTH(u);
goto fast_next_opcode;
case DUP_TOP:
v = TOP();
Py_INCREF(v);
PUSH(v);
goto fast_next_opcode;
case DUP_TOPX:
if (oparg == 2) {
x = TOP();
Py_INCREF(x);
w = SECOND();
Py_INCREF(w);
STACKADJ(2);
SET_TOP(x);
SET_SECOND(w);
goto fast_next_opcode;
} else if (oparg == 3) {
x = TOP();
Py_INCREF(x);
w = SECOND();
Py_INCREF(w);
v = THIRD();
Py_INCREF(v);
STACKADJ(3);
SET_TOP(x);
SET_SECOND(w);
SET_THIRD(v);
goto fast_next_opcode;
}
Py_FatalError("invalid argument to DUP_TOPX"
" (bytecode corruption?)");
break;
case UNARY_POSITIVE:
v = TOP();
x = PyNumber_Positive(v);
Py_DECREF(v);
SET_TOP(x);
if (x != NULL) continue;
break;
case UNARY_NEGATIVE:
v = TOP();
x = PyNumber_Negative(v);
Py_DECREF(v);
SET_TOP(x);
if (x != NULL) continue;
break;
case UNARY_NOT:
v = TOP();
err = PyObject_IsTrue(v);
Py_DECREF(v);
if (err == 0) {
Py_INCREF(Py_True);
SET_TOP(Py_True);
continue;
}
else if (err > 0) {
Py_INCREF(Py_False);
SET_TOP(Py_False);
err = 0;
continue;
}
STACKADJ(-1);
break;
case UNARY_CONVERT:
v = TOP();
x = PyObject_Repr(v);
Py_DECREF(v);
SET_TOP(x);
if (x != NULL) continue;
break;
case UNARY_INVERT:
v = TOP();
x = PyNumber_Invert(v);
Py_DECREF(v);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_POWER:
w = POP();
v = TOP();
x = PyNumber_Power(v, w, Py_None);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_MULTIPLY:
w = POP();
v = TOP();
x = PyNumber_Multiply(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_DIVIDE:
if (!_Py_QnewFlag) {
w = POP();
v = TOP();
x = PyNumber_Divide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
}
/* -Qnew is in effect: fall through to
BINARY_TRUE_DIVIDE */
case BINARY_TRUE_DIVIDE:
w = POP();
v = TOP();
x = PyNumber_TrueDivide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_FLOOR_DIVIDE:
w = POP();
v = TOP();
x = PyNumber_FloorDivide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_MODULO:
w = POP();
v = TOP();
x = PyNumber_Remainder(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_ADD:
w = POP();
v = TOP();
if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) {
/* INLINE: int + int */
register long a, b, i;
a = PyInt_AS_LONG(v);
b = PyInt_AS_LONG(w);
i = a + b;
if ((i^a) < 0 && (i^b) < 0)
goto slow_add;
x = PyInt_FromLong(i);
}
else {
slow_add:
x = PyNumber_Add(v, w);
}
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_SUBTRACT:
w = POP();
v = TOP();
if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) {
/* INLINE: int - int */
register long a, b, i;
a = PyInt_AS_LONG(v);
b = PyInt_AS_LONG(w);
i = a - b;
if ((i^a) < 0 && (i^~b) < 0)
goto slow_sub;
x = PyInt_FromLong(i);
}
else {
slow_sub:
x = PyNumber_Subtract(v, w);
}
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_SUBSCR:
w = POP();
v = TOP();
if (PyList_CheckExact(v) && PyInt_CheckExact(w)) {
/* INLINE: list[int] */
long i = PyInt_AsLong(w);
if (i < 0)
i += PyList_GET_SIZE(v);
if (i >= 0 && i < PyList_GET_SIZE(v)) {
x = PyList_GET_ITEM(v, i);
Py_INCREF(x);
}
else
goto slow_get;
}
else
slow_get:
x = PyObject_GetItem(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_LSHIFT:
w = POP();
v = TOP();
x = PyNumber_Lshift(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_RSHIFT:
w = POP();
v = TOP();
x = PyNumber_Rshift(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_AND:
w = POP();
v = TOP();
x = PyNumber_And(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_XOR:
w = POP();
v = TOP();
x = PyNumber_Xor(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case BINARY_OR:
w = POP();
v = TOP();
x = PyNumber_Or(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case LIST_APPEND:
w = POP();
v = POP();
err = PyList_Append(v, w);
Py_DECREF(v);
Py_DECREF(w);
if (err == 0) {
PREDICT(JUMP_ABSOLUTE);
continue;
}
break;
case INPLACE_POWER:
w = POP();
v = TOP();
x = PyNumber_InPlacePower(v, w, Py_None);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_MULTIPLY:
w = POP();
v = TOP();
x = PyNumber_InPlaceMultiply(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_DIVIDE:
if (!_Py_QnewFlag) {
w = POP();
v = TOP();
x = PyNumber_InPlaceDivide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
}
/* -Qnew is in effect: fall through to
INPLACE_TRUE_DIVIDE */
case INPLACE_TRUE_DIVIDE:
w = POP();
v = TOP();
x = PyNumber_InPlaceTrueDivide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_FLOOR_DIVIDE:
w = POP();
v = TOP();
x = PyNumber_InPlaceFloorDivide(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_MODULO:
w = POP();
v = TOP();
x = PyNumber_InPlaceRemainder(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_ADD:
w = POP();
v = TOP();
if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) {
/* INLINE: int + int */
register long a, b, i;
a = PyInt_AS_LONG(v);
b = PyInt_AS_LONG(w);
i = a + b;
if ((i^a) < 0 && (i^b) < 0)
goto slow_iadd;
x = PyInt_FromLong(i);
}
else {
slow_iadd:
x = PyNumber_InPlaceAdd(v, w);
}
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_SUBTRACT:
w = POP();
v = TOP();
if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) {
/* INLINE: int - int */
register long a, b, i;
a = PyInt_AS_LONG(v);
b = PyInt_AS_LONG(w);
i = a - b;
if ((i^a) < 0 && (i^~b) < 0)
goto slow_isub;
x = PyInt_FromLong(i);
}
else {
slow_isub:
x = PyNumber_InPlaceSubtract(v, w);
}
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_LSHIFT:
w = POP();
v = TOP();
x = PyNumber_InPlaceLshift(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_RSHIFT:
w = POP();
v = TOP();
x = PyNumber_InPlaceRshift(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_AND:
w = POP();
v = TOP();
x = PyNumber_InPlaceAnd(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_XOR:
w = POP();
v = TOP();
x = PyNumber_InPlaceXor(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case INPLACE_OR:
w = POP();
v = TOP();
x = PyNumber_InPlaceOr(v, w);
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case SLICE+0:
case SLICE+1:
case SLICE+2:
case SLICE+3:
if ((opcode-SLICE) & 2)
w = POP();
else
w = NULL;
if ((opcode-SLICE) & 1)
v = POP();
else
v = NULL;
u = TOP();
x = apply_slice(u, v, w);
Py_DECREF(u);
Py_XDECREF(v);
Py_XDECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case STORE_SLICE+0:
case STORE_SLICE+1:
case STORE_SLICE+2:
case STORE_SLICE+3:
if ((opcode-STORE_SLICE) & 2)
w = POP();
else
w = NULL;
if ((opcode-STORE_SLICE) & 1)
v = POP();
else
v = NULL;
u = POP();
t = POP();
err = assign_slice(u, v, w, t); /* u[v:w] = t */
Py_DECREF(t);
Py_DECREF(u);
Py_XDECREF(v);
Py_XDECREF(w);
if (err == 0) continue;
break;
case DELETE_SLICE+0:
case DELETE_SLICE+1:
case DELETE_SLICE+2:
case DELETE_SLICE+3:
if ((opcode-DELETE_SLICE) & 2)
w = POP();
else
w = NULL;
if ((opcode-DELETE_SLICE) & 1)
v = POP();
else
v = NULL;
u = POP();
err = assign_slice(u, v, w, (PyObject *)NULL);
/* del u[v:w] */
Py_DECREF(u);
Py_XDECREF(v);
Py_XDECREF(w);
if (err == 0) continue;
break;
case STORE_SUBSCR:
w = TOP();
v = SECOND();
u = THIRD();
STACKADJ(-3);
/* v[w] = u */
err = PyObject_SetItem(v, w, u);
Py_DECREF(u);
Py_DECREF(v);
Py_DECREF(w);
if (err == 0) continue;
break;
case DELETE_SUBSCR:
w = TOP();
v = SECOND();
STACKADJ(-2);
/* del v[w] */
err = PyObject_DelItem(v, w);
Py_DECREF(v);
Py_DECREF(w);
if (err == 0) continue;
break;
case PRINT_EXPR:
v = POP();
w = PySys_GetObject("displayhook");
if (w == NULL) {
PyErr_SetString(PyExc_RuntimeError,
"lost sys.displayhook");
err = -1;
x = NULL;
}
if (err == 0) {
x = PyTuple_Pack(1, v);
if (x == NULL)
err = -1;
}
if (err == 0) {
w = PyEval_CallObject(w, x);
Py_XDECREF(w);
if (w == NULL)
err = -1;
}
Py_DECREF(v);
Py_XDECREF(x);
break;
case PRINT_ITEM_TO:
w = stream = POP();
/* fall through to PRINT_ITEM */
case PRINT_ITEM:
v = POP();
if (stream == NULL || stream == Py_None) {
w = PySys_GetObject("stdout");
if (w == NULL) {
PyErr_SetString(PyExc_RuntimeError,
"lost sys.stdout");
err = -1;
}
}
/* PyFile_SoftSpace() can exececute arbitrary code
if sys.stdout is an instance with a __getattr__.
If __getattr__ raises an exception, w will
be freed, so we need to prevent that temporarily. */
Py_XINCREF(w);
if (w != NULL && PyFile_SoftSpace(w, 0))
err = PyFile_WriteString(" ", w);
if (err == 0)
err = PyFile_WriteObject(v, w, Py_PRINT_RAW);
if (err == 0) {
/* XXX move into writeobject() ? */
if (PyString_Check(v)) {
char *s = PyString_AS_STRING(v);
int len = PyString_GET_SIZE(v);
if (len == 0 ||
!isspace(Py_CHARMASK(s[len-1])) ||
s[len-1] == ' ')
PyFile_SoftSpace(w, 1);
}
#ifdef Py_USING_UNICODE
else if (PyUnicode_Check(v)) {
Py_UNICODE *s = PyUnicode_AS_UNICODE(v);
int len = PyUnicode_GET_SIZE(v);
if (len == 0 ||
!Py_UNICODE_ISSPACE(s[len-1]) ||
s[len-1] == ' ')
PyFile_SoftSpace(w, 1);
}
#endif
else
PyFile_SoftSpace(w, 1);
}
Py_XDECREF(w);
Py_DECREF(v);
Py_XDECREF(stream);
stream = NULL;
if (err == 0)
continue;
break;
case PRINT_NEWLINE_TO:
w = stream = POP();
/* fall through to PRINT_NEWLINE */
case PRINT_NEWLINE:
if (stream == NULL || stream == Py_None) {
w = PySys_GetObject("stdout");
if (w == NULL)
PyErr_SetString(PyExc_RuntimeError,
"lost sys.stdout");
}
if (w != NULL) {
err = PyFile_WriteString("\n", w);
if (err == 0)
PyFile_SoftSpace(w, 0);
}
Py_XDECREF(stream);
stream = NULL;
break;
#ifdef CASE_TOO_BIG
default: switch (opcode) {
#endif
case RAISE_VARARGS:
u = v = w = NULL;
switch (oparg) {
case 3:
u = POP(); /* traceback */
/* Fallthrough */
case 2:
v = POP(); /* value */
/* Fallthrough */
case 1:
w = POP(); /* exc */
case 0: /* Fallthrough */
why = do_raise(w, v, u);
break;
default:
PyErr_SetString(PyExc_SystemError,
"bad RAISE_VARARGS oparg");
why = WHY_EXCEPTION;
break;
}
break;
case LOAD_LOCALS:
if ((x = f->f_locals) != NULL) {
Py_INCREF(x);
PUSH(x);
continue;
}
PyErr_SetString(PyExc_SystemError, "no locals");
break;
case RETURN_VALUE:
retval = POP();
why = WHY_RETURN;
goto fast_block_end;
case YIELD_VALUE:
retval = POP();
f->f_stacktop = stack_pointer;
why = WHY_YIELD;
goto fast_yield;
case EXEC_STMT:
w = TOP();
v = SECOND();
u = THIRD();
STACKADJ(-3);
err = exec_statement(f, u, v, w);
Py_DECREF(u);
Py_DECREF(v);
Py_DECREF(w);
break;
case POP_BLOCK:
{
PyTryBlock *b = PyFrame_BlockPop(f);
while (STACK_LEVEL() > b->b_level) {
v = POP();
Py_DECREF(v);
}
}
continue;
case END_FINALLY:
v = POP();
if (PyInt_Check(v)) {
why = (enum why_code) PyInt_AS_LONG(v);
assert(why != WHY_YIELD);
if (why & (WHY_RETURN | WHY_CONTINUE))
retval = POP();
}
else if (PyClass_Check(v) || PyString_Check(v)) {
w = POP();
u = POP();
PyErr_Restore(v, w, u);
why = WHY_RERAISE;
break;
}
else if (v != Py_None) {
PyErr_SetString(PyExc_SystemError,
"'finally' pops bad exception");
why = WHY_EXCEPTION;
}
Py_DECREF(v);
break;
case BUILD_CLASS:
u = TOP();
v = SECOND();
w = THIRD();
STACKADJ(-2);
x = build_class(u, v, w);
SET_TOP(x);
Py_DECREF(u);
Py_DECREF(v);
Py_DECREF(w);
break;
case STORE_NAME:
w = GETITEM(names, oparg);
v = POP();
if ((x = f->f_locals) != NULL) {
err = PyDict_SetItem(x, w, v);
Py_DECREF(v);
if (err == 0) continue;
break;
}
PyErr_Format(PyExc_SystemError,
"no locals found when storing %s",
PyObject_REPR(w));
break;
case DELETE_NAME:
w = GETITEM(names, oparg);
if ((x = f->f_locals) != NULL) {
if ((err = PyDict_DelItem(x, w)) != 0)
format_exc_check_arg(PyExc_NameError,
NAME_ERROR_MSG ,w);
break;
}
PyErr_Format(PyExc_SystemError,
"no locals when deleting %s",
PyObject_REPR(w));
break;
PREDICTED_WITH_ARG(UNPACK_SEQUENCE);
case UNPACK_SEQUENCE:
v = POP();
if (PyTuple_CheckExact(v) && PyTuple_GET_SIZE(v) == oparg) {
PyObject **items = ((PyTupleObject *)v)->ob_item;
while (oparg--) {
w = items[oparg];
Py_INCREF(w);
PUSH(w);
}
Py_DECREF(v);
continue;
} else if (PyList_CheckExact(v) && PyList_GET_SIZE(v) == oparg) {
PyObject **items = ((PyListObject *)v)->ob_item;
while (oparg--) {
w = items[oparg];
Py_INCREF(w);
PUSH(w);
}
} else if (unpack_iterable(v, oparg,
stack_pointer + oparg))
stack_pointer += oparg;
else {
if (PyErr_ExceptionMatches(PyExc_TypeError))
PyErr_SetString(PyExc_TypeError,
"unpack non-sequence");
why = WHY_EXCEPTION;
}
Py_DECREF(v);
break;
case STORE_ATTR:
w = GETITEM(names, oparg);
v = TOP();
u = SECOND();
STACKADJ(-2);
err = PyObject_SetAttr(v, w, u); /* v.w = u */
Py_DECREF(v);
Py_DECREF(u);
if (err == 0) continue;
break;
case DELETE_ATTR:
w = GETITEM(names, oparg);
v = POP();
err = PyObject_SetAttr(v, w, (PyObject *)NULL);
/* del v.w */
Py_DECREF(v);
break;
case STORE_GLOBAL:
w = GETITEM(names, oparg);
v = POP();
err = PyDict_SetItem(f->f_globals, w, v);
Py_DECREF(v);
if (err == 0) continue;
break;
case DELETE_GLOBAL:
w = GETITEM(names, oparg);
if ((err = PyDict_DelItem(f->f_globals, w)) != 0)
format_exc_check_arg(
PyExc_NameError, GLOBAL_NAME_ERROR_MSG, w);
break;
case LOAD_NAME:
w = GETITEM(names, oparg);
if ((x = f->f_locals) == NULL) {
PyErr_Format(PyExc_SystemError,
"no locals when loading %s",
PyObject_REPR(w));
break;
}
x = PyDict_GetItem(x, w);
if (x == NULL) {
x = PyDict_GetItem(f->f_globals, w);
if (x == NULL) {
x = PyDict_GetItem(f->f_builtins, w);
if (x == NULL) {
format_exc_check_arg(
PyExc_NameError,
NAME_ERROR_MSG ,w);
break;
}
}
}
Py_INCREF(x);
PUSH(x);
continue;
case LOAD_GLOBAL:
w = GETITEM(names, oparg);
if (PyString_CheckExact(w)) {
/* Inline the PyDict_GetItem() calls.
WARNING: this is an extreme speed hack.
Do not try this at home. */
long hash = ((PyStringObject *)w)->ob_shash;
if (hash != -1) {
PyDictObject *d;
d = (PyDictObject *)(f->f_globals);
x = d->ma_lookup(d, w, hash)->me_value;
if (x != NULL) {
Py_INCREF(x);
PUSH(x);
continue;
}
d = (PyDictObject *)(f->f_builtins);
x = d->ma_lookup(d, w, hash)->me_value;
if (x != NULL) {
Py_INCREF(x);
PUSH(x);
continue;
}
goto load_global_error;
}
}
/* This is the un-inlined version of the code above */
x = PyDict_GetItem(f->f_globals, w);
if (x == NULL) {
x = PyDict_GetItem(f->f_builtins, w);
if (x == NULL) {
load_global_error:
format_exc_check_arg(
PyExc_NameError,
GLOBAL_NAME_ERROR_MSG, w);
break;
}
}
Py_INCREF(x);
PUSH(x);
continue;
case DELETE_FAST:
x = GETLOCAL(oparg);
if (x != NULL) {
SETLOCAL(oparg, NULL);
continue;
}
format_exc_check_arg(
PyExc_UnboundLocalError,
UNBOUNDLOCAL_ERROR_MSG,
PyTuple_GetItem(co->co_varnames, oparg)
);
break;
case LOAD_CLOSURE:
x = freevars[oparg];
Py_INCREF(x);
PUSH(x);
if (x != NULL) continue;
break;
case LOAD_DEREF:
x = freevars[oparg];
w = PyCell_Get(x);
if (w != NULL) {
PUSH(w);
continue;
}
err = -1;
/* Don't stomp existing exception */
if (PyErr_Occurred())
break;
if (oparg < f->f_ncells) {
v = PyTuple_GetItem(co->co_cellvars,
oparg);
format_exc_check_arg(
PyExc_UnboundLocalError,
UNBOUNDLOCAL_ERROR_MSG,
v);
} else {
v = PyTuple_GetItem(
co->co_freevars,
oparg - f->f_ncells);
format_exc_check_arg(
PyExc_NameError,
UNBOUNDFREE_ERROR_MSG,
v);
}
break;
case STORE_DEREF:
w = POP();
x = freevars[oparg];
PyCell_Set(x, w);
Py_DECREF(w);
continue;
case BUILD_TUPLE:
x = PyTuple_New(oparg);
if (x != NULL) {
while (oparg--) {
w = POP();
PyTuple_SET_ITEM(x, oparg, w);
}
PUSH(x);
continue;
}
break;
case BUILD_LIST:
x = PyList_New(oparg);
if (x != NULL) {
while (oparg--) {
w = POP();
PyList_SET_ITEM(x, oparg, w);
}
PUSH(x);
continue;
}
break;
case BUILD_MAP:
x = PyDict_New();
PUSH(x);
if (x != NULL) continue;
break;
case LOAD_ATTR:
w = GETITEM(names, oparg);
v = TOP();
x = PyObject_GetAttr(v, w);
Py_DECREF(v);
SET_TOP(x);
if (x != NULL) continue;
break;
case COMPARE_OP:
w = POP();
v = TOP();
if (PyInt_CheckExact(w) && PyInt_CheckExact(v)) {
/* INLINE: cmp(int, int) */
register long a, b;
register int res;
a = PyInt_AS_LONG(v);
b = PyInt_AS_LONG(w);
switch (oparg) {
case PyCmp_LT: res = a < b; break;
case PyCmp_LE: res = a <= b; break;
case PyCmp_EQ: res = a == b; break;
case PyCmp_NE: res = a != b; break;
case PyCmp_GT: res = a > b; break;
case PyCmp_GE: res = a >= b; break;
case PyCmp_IS: res = v == w; break;
case PyCmp_IS_NOT: res = v != w; break;
default: goto slow_compare;
}
x = res ? Py_True : Py_False;
Py_INCREF(x);
}
else {
slow_compare:
x = cmp_outcome(oparg, v, w);
}
Py_DECREF(v);
Py_DECREF(w);
SET_TOP(x);
if (x == NULL) break;
PREDICT(JUMP_IF_FALSE);
PREDICT(JUMP_IF_TRUE);
continue;
case IMPORT_NAME:
w = GETITEM(names, oparg);
x = PyDict_GetItemString(f->f_builtins, "__import__");
if (x == NULL) {
PyErr_SetString(PyExc_ImportError,
"__import__ not found");
break;
}
u = TOP();
w = PyTuple_Pack(4,
w,
f->f_globals,
f->f_locals == NULL ?
Py_None : f->f_locals,
u);
Py_DECREF(u);
if (w == NULL) {
u = POP();
x = NULL;
break;
}
x = PyEval_CallObject(x, w);
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case IMPORT_STAR:
v = POP();
PyFrame_FastToLocals(f);
if ((x = f->f_locals) == NULL) {
PyErr_SetString(PyExc_SystemError,
"no locals found during 'import *'");
break;
}
err = import_all_from(x, v);
PyFrame_LocalsToFast(f, 0);
Py_DECREF(v);
if (err == 0) continue;
break;
case IMPORT_FROM:
w = GETITEM(names, oparg);
v = TOP();
x = import_from(v, w);
PUSH(x);
if (x != NULL) continue;
break;
case JUMP_FORWARD:
JUMPBY(oparg);
goto fast_next_opcode;
PREDICTED_WITH_ARG(JUMP_IF_FALSE);
case JUMP_IF_FALSE:
w = TOP();
if (w == Py_True) {
PREDICT(POP_TOP);
goto fast_next_opcode;
}
if (w == Py_False) {
JUMPBY(oparg);
goto fast_next_opcode;
}
err = PyObject_IsTrue(w);
if (err > 0)
err = 0;
else if (err == 0)
JUMPBY(oparg);
else
break;
continue;
PREDICTED_WITH_ARG(JUMP_IF_TRUE);
case JUMP_IF_TRUE:
w = TOP();
if (w == Py_False) {
PREDICT(POP_TOP);
goto fast_next_opcode;
}
if (w == Py_True) {
JUMPBY(oparg);
goto fast_next_opcode;
}
err = PyObject_IsTrue(w);
if (err > 0) {
err = 0;
JUMPBY(oparg);
}
else if (err == 0)
;
else
break;
continue;
PREDICTED_WITH_ARG(JUMP_ABSOLUTE);
case JUMP_ABSOLUTE:
JUMPTO(oparg);
continue;
case GET_ITER:
/* before: [obj]; after [getiter(obj)] */
v = TOP();
x = PyObject_GetIter(v);
Py_DECREF(v);
if (x != NULL) {
SET_TOP(x);
PREDICT(FOR_ITER);
continue;
}
STACKADJ(-1);
break;
PREDICTED_WITH_ARG(FOR_ITER);
case FOR_ITER:
/* before: [iter]; after: [iter, iter()] *or* [] */
v = TOP();
x = (*v->ob_type->tp_iternext)(v);
if (x != NULL) {
PUSH(x);
PREDICT(STORE_FAST);
PREDICT(UNPACK_SEQUENCE);
continue;
}
if (PyErr_Occurred()) {
if (!PyErr_ExceptionMatches(PyExc_StopIteration))
break;
PyErr_Clear();
}
/* iterator ended normally */
x = v = POP();
Py_DECREF(v);
JUMPBY(oparg);
continue;
case BREAK_LOOP:
why = WHY_BREAK;
goto fast_block_end;
case CONTINUE_LOOP:
retval = PyInt_FromLong(oparg);
why = WHY_CONTINUE;
goto fast_block_end;
case SETUP_LOOP:
case SETUP_EXCEPT:
case SETUP_FINALLY:
PyFrame_BlockSetup(f, opcode, INSTR_OFFSET() + oparg,
STACK_LEVEL());
continue;
case CALL_FUNCTION:
PCALL(PCALL_ALL);
x = call_function(&stack_pointer, oparg);
PUSH(x);
if (x != NULL)
continue;
break;
case CALL_FUNCTION_VAR:
case CALL_FUNCTION_KW:
case CALL_FUNCTION_VAR_KW:
{
int na = oparg & 0xff;
int nk = (oparg>>8) & 0xff;
int flags = (opcode - CALL_FUNCTION) & 3;
int n = na + 2 * nk;
PyObject **pfunc, *func;
PCALL(PCALL_ALL);
if (flags & CALL_FLAG_VAR)
n++;
if (flags & CALL_FLAG_KW)
n++;
pfunc = stack_pointer - n - 1;
func = *pfunc;
if (PyMethod_Check(func)
&& PyMethod_GET_SELF(func) != NULL) {
PyObject *self = PyMethod_GET_SELF(func);
Py_INCREF(self);
func = PyMethod_GET_FUNCTION(func);
Py_INCREF(func);
Py_DECREF(*pfunc);
*pfunc = self;
na++;
n++;
} else
Py_INCREF(func);
x = ext_do_call(func, &stack_pointer, flags, na, nk);
Py_DECREF(func);
while (stack_pointer > pfunc) {
w = POP();
Py_DECREF(w);
}
PUSH(x);
if (x != NULL)
continue;
break;
}
case MAKE_FUNCTION:
v = POP(); /* code object */
x = PyFunction_New(v, f->f_globals);
Py_DECREF(v);
/* XXX Maybe this should be a separate opcode? */
if (x != NULL && oparg > 0) {
v = PyTuple_New(oparg);
if (v == NULL) {
Py_DECREF(x);
x = NULL;
break;
}
while (oparg--) {
w = POP();
PyTuple_SET_ITEM(v, oparg, w);
}
err = PyFunction_SetDefaults(x, v);
Py_DECREF(v);
}
PUSH(x);
break;
case MAKE_CLOSURE:
{
int nfree;
v = POP(); /* code object */
x = PyFunction_New(v, f->f_globals);
nfree = PyCode_GetNumFree((PyCodeObject *)v);
Py_DECREF(v);
/* XXX Maybe this should be a separate opcode? */
if (x != NULL && nfree > 0) {
v = PyTuple_New(nfree);
if (v == NULL) {
Py_DECREF(x);
x = NULL;
break;
}
while (nfree--) {
w = POP();
PyTuple_SET_ITEM(v, nfree, w);
}
err = PyFunction_SetClosure(x, v);
Py_DECREF(v);
}
if (x != NULL && oparg > 0) {
v = PyTuple_New(oparg);
if (v == NULL) {
Py_DECREF(x);
x = NULL;
break;
}
while (oparg--) {
w = POP();
PyTuple_SET_ITEM(v, oparg, w);
}
err = PyFunction_SetDefaults(x, v);
Py_DECREF(v);
}
PUSH(x);
break;
}
case BUILD_SLICE:
if (oparg == 3)
w = POP();
else
w = NULL;
v = POP();
u = TOP();
x = PySlice_New(u, v, w);
Py_DECREF(u);
Py_DECREF(v);
Py_XDECREF(w);
SET_TOP(x);
if (x != NULL) continue;
break;
case EXTENDED_ARG:
opcode = NEXTOP();
oparg = oparg<<16 | OPARG();
SKIPARG();
goto dispatch_opcode;
default:
fprintf(stderr,
"XXX lineno: %d, opcode: %d\n",
PyCode_Addr2Line(f->f_code, f->f_lasti),
opcode);
PyErr_SetString(PyExc_SystemError, "unknown opcode");
why = WHY_EXCEPTION;
break;
#ifdef CASE_TOO_BIG
}
#endif
} /* switch */
on_error:
/* Quickly continue if no error occurred */
if (why == WHY_NOT) {
if (err == 0 && x != NULL) {
#ifdef CHECKEXC
/* This check is expensive! */
if (PyErr_Occurred())
fprintf(stderr,
"XXX undetected error\n");
else
#endif
continue; /* Normal, fast path */
}
why = WHY_EXCEPTION;
x = Py_None;
err = 0;
}
/* Double-check exception status */
if (why & (WHY_EXCEPTION | WHY_RERAISE)) {
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_SystemError,
"error return without exception set");
why = WHY_EXCEPTION;
}
}
#ifdef CHECKEXC
else {
/* This check is expensive! */
if (PyErr_Occurred()) {
char buf[1024];
sprintf(buf, "Stack unwind with exception "
"set and why=%d", why);
Py_FatalError(buf);
}
}
#endif
/* Log traceback info if this is a real exception */
if (why == WHY_EXCEPTION) {
PyTraceBack_Here(f);
if (tstate->c_tracefunc != NULL)
call_exc_trace(tstate->c_tracefunc,
tstate->c_traceobj, f);
}
/* For the rest, treat WHY_RERAISE as WHY_EXCEPTION */
if (why == WHY_RERAISE)
why = WHY_EXCEPTION;
/* Unwind stacks if a (pseudo) exception occurred */
fast_block_end:
while (why != WHY_NOT && f->f_iblock > 0) {
PyTryBlock *b = PyFrame_BlockPop(f);
assert(why != WHY_YIELD);
if (b->b_type == SETUP_LOOP && why == WHY_CONTINUE) {
/* For a continue inside a try block,
don't pop the block for the loop. */
PyFrame_BlockSetup(f, b->b_type, b->b_handler,
b->b_level);
why = WHY_NOT;
JUMPTO(PyInt_AS_LONG(retval));
Py_DECREF(retval);
break;
}
while (STACK_LEVEL() > b->b_level) {
v = POP();
Py_XDECREF(v);
}
if (b->b_type == SETUP_LOOP && why == WHY_BREAK) {
why = WHY_NOT;
JUMPTO(b->b_handler);
break;
}
if (b->b_type == SETUP_FINALLY ||
(b->b_type == SETUP_EXCEPT &&
why == WHY_EXCEPTION)) {
if (why == WHY_EXCEPTION) {
PyObject *exc, *val, *tb;
PyErr_Fetch(&exc, &val, &tb);
if (val == NULL) {
val = Py_None;
Py_INCREF(val);
}
/* Make the raw exception data
available to the handler,
so a program can emulate the
Python main loop. Don't do
this for 'finally'. */
if (b->b_type == SETUP_EXCEPT) {
PyErr_NormalizeException(
&exc, &val, &tb);
set_exc_info(tstate,
exc, val, tb);
}
if (tb == NULL) {
Py_INCREF(Py_None);
PUSH(Py_None);
} else
PUSH(tb);
PUSH(val);
PUSH(exc);
}
else {
if (why & (WHY_RETURN | WHY_CONTINUE))
PUSH(retval);
v = PyInt_FromLong((long)why);
PUSH(v);
}
why = WHY_NOT;
JUMPTO(b->b_handler);
break;
}
} /* unwind stack */
/* End the loop if we still have an error (or return) */
if (why != WHY_NOT)
break;
} /* main loop */
assert(why != WHY_YIELD);
/* Pop remaining stack entries. */
while (!EMPTY()) {
v = POP();
Py_XDECREF(v);
}
if (why != WHY_RETURN)
retval = NULL;
fast_yield:
if (tstate->use_tracing) {
if (tstate->c_tracefunc
&& (why & (WHY_RETURN | WHY_YIELD))) {
if (call_trace(tstate->c_tracefunc,
tstate->c_traceobj, f,
PyTrace_RETURN, retval)) {
Py_XDECREF(retval);
retval = NULL;
why = WHY_EXCEPTION;
}
}
if (tstate->c_profilefunc) {
if (why == WHY_EXCEPTION)
call_trace_protected(tstate->c_profilefunc,
tstate->c_profileobj, f,
PyTrace_RETURN);
else if (call_trace(tstate->c_profilefunc,
tstate->c_profileobj, f,
PyTrace_RETURN, retval)) {
Py_XDECREF(retval);
retval = NULL;
why = WHY_EXCEPTION;
}
}
}
reset_exc_info(tstate);
/* pop frame */
exit_eval_frame:
Py_LeaveRecursiveCall();
tstate->frame = f->f_back;
return retval;
}
/* this is gonna seem *real weird*, but if you put some other code between
eval_frame() and PyEval_EvalCodeEx() you will need to adjust the test in
the if statement in Misc/gdbinit:ppystack */
PyObject *
PyEval_EvalCodeEx(PyCodeObject *co, PyObject *globals, PyObject *locals,
PyObject **args, int argcount, PyObject **kws, int kwcount,
PyObject **defs, int defcount, PyObject *closure)
{
register PyFrameObject *f;
register PyObject *retval = NULL;
register PyObject **fastlocals, **freevars;
PyThreadState *tstate = PyThreadState_GET();
PyObject *x, *u;
if (globals == NULL) {
PyErr_SetString(PyExc_SystemError,
"PyEval_EvalCodeEx: NULL globals");
return NULL;
}
assert(globals != NULL);
f = PyFrame_New(tstate, co, globals, locals);
if (f == NULL)
return NULL;
fastlocals = f->f_localsplus;
freevars = f->f_localsplus + f->f_nlocals;
if (co->co_argcount > 0 ||
co->co_flags & (CO_VARARGS | CO_VARKEYWORDS)) {
int i;
int n = argcount;
PyObject *kwdict = NULL;
if (co->co_flags & CO_VARKEYWORDS) {
kwdict = PyDict_New();
if (kwdict == NULL)
goto fail;
i = co->co_argcount;
if (co->co_flags & CO_VARARGS)
i++;
SETLOCAL(i, kwdict);
}
if (argcount > co->co_argcount) {
if (!(co->co_flags & CO_VARARGS)) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes %s %d "
"%sargument%s (%d given)",
PyString_AsString(co->co_name),
defcount ? "at most" : "exactly",
co->co_argcount,
kwcount ? "non-keyword " : "",
co->co_argcount == 1 ? "" : "s",
argcount);
goto fail;
}
n = co->co_argcount;
}
for (i = 0; i < n; i++) {
x = args[i];
Py_INCREF(x);
SETLOCAL(i, x);
}
if (co->co_flags & CO_VARARGS) {
u = PyTuple_New(argcount - n);
if (u == NULL)
goto fail;
SETLOCAL(co->co_argcount, u);
for (i = n; i < argcount; i++) {
x = args[i];
Py_INCREF(x);
PyTuple_SET_ITEM(u, i-n, x);
}
}
for (i = 0; i < kwcount; i++) {
PyObject *keyword = kws[2*i];
PyObject *value = kws[2*i + 1];
int j;
if (keyword == NULL || !PyString_Check(keyword)) {
PyErr_Format(PyExc_TypeError,
"%.200s() keywords must be strings",
PyString_AsString(co->co_name));
goto fail;
}
/* XXX slow -- speed up using dictionary? */
for (j = 0; j < co->co_argcount; j++) {
PyObject *nm = PyTuple_GET_ITEM(
co->co_varnames, j);
int cmp = PyObject_RichCompareBool(
keyword, nm, Py_EQ);
if (cmp > 0)
break;
else if (cmp < 0)
goto fail;
}
/* Check errors from Compare */
if (PyErr_Occurred())
goto fail;
if (j >= co->co_argcount) {
if (kwdict == NULL) {
PyErr_Format(PyExc_TypeError,
"%.200s() got an unexpected "
"keyword argument '%.400s'",
PyString_AsString(co->co_name),
PyString_AsString(keyword));
goto fail;
}
PyDict_SetItem(kwdict, keyword, value);
}
else {
if (GETLOCAL(j) != NULL) {
PyErr_Format(PyExc_TypeError,
"%.200s() got multiple "
"values for keyword "
"argument '%.400s'",
PyString_AsString(co->co_name),
PyString_AsString(keyword));
goto fail;
}
Py_INCREF(value);
SETLOCAL(j, value);
}
}
if (argcount < co->co_argcount) {
int m = co->co_argcount - defcount;
for (i = argcount; i < m; i++) {
if (GETLOCAL(i) == NULL) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes %s %d "
"%sargument%s (%d given)",
PyString_AsString(co->co_name),
((co->co_flags & CO_VARARGS) ||
defcount) ? "at least"
: "exactly",
m, kwcount ? "non-keyword " : "",
m == 1 ? "" : "s", i);
goto fail;
}
}
if (n > m)
i = n - m;
else
i = 0;
for (; i < defcount; i++) {
if (GETLOCAL(m+i) == NULL) {
PyObject *def = defs[i];
Py_INCREF(def);
SETLOCAL(m+i, def);
}
}
}
}
else {
if (argcount > 0 || kwcount > 0) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes no arguments (%d given)",
PyString_AsString(co->co_name),
argcount + kwcount);
goto fail;
}
}
/* Allocate and initialize storage for cell vars, and copy free
vars into frame. This isn't too efficient right now. */
if (f->f_ncells) {
int i = 0, j = 0, nargs, found;
char *cellname, *argname;
PyObject *c;
nargs = co->co_argcount;
if (co->co_flags & CO_VARARGS)
nargs++;
if (co->co_flags & CO_VARKEYWORDS)
nargs++;
/* Check for cells that shadow args */
for (i = 0; i < f->f_ncells && j < nargs; ++i) {
cellname = PyString_AS_STRING(
PyTuple_GET_ITEM(co->co_cellvars, i));
found = 0;
while (j < nargs) {
argname = PyString_AS_STRING(
PyTuple_GET_ITEM(co->co_varnames, j));
if (strcmp(cellname, argname) == 0) {
c = PyCell_New(GETLOCAL(j));
if (c == NULL)
goto fail;
GETLOCAL(f->f_nlocals + i) = c;
found = 1;
break;
}
j++;
}
if (found == 0) {
c = PyCell_New(NULL);
if (c == NULL)
goto fail;
SETLOCAL(f->f_nlocals + i, c);
}
}
/* Initialize any that are left */
while (i < f->f_ncells) {
c = PyCell_New(NULL);
if (c == NULL)
goto fail;
SETLOCAL(f->f_nlocals + i, c);
i++;
}
}
if (f->f_nfreevars) {
int i;
for (i = 0; i < f->f_nfreevars; ++i) {
PyObject *o = PyTuple_GET_ITEM(closure, i);
Py_INCREF(o);
freevars[f->f_ncells + i] = o;
}
}
if (co->co_flags & CO_GENERATOR) {
/* Don't need to keep the reference to f_back, it will be set
* when the generator is resumed. */
Py_XDECREF(f->f_back);
f->f_back = NULL;
PCALL(PCALL_GENERATOR);
/* Create a new generator that owns the ready to run frame
* and return that as the value. */
return gen_new(f);
}
retval = eval_frame(f);
fail: /* Jump here from prelude on failure */
/* decref'ing the frame can cause __del__ methods to get invoked,
which can call back into Python. While we're done with the
current Python frame (f), the associated C stack is still in use,
so recursion_depth must be boosted for the duration.
*/
assert(tstate != NULL);
++tstate->recursion_depth;
Py_DECREF(f);
--tstate->recursion_depth;
return retval;
}
/* Implementation notes for set_exc_info() and reset_exc_info():
- Below, 'exc_ZZZ' stands for 'exc_type', 'exc_value' and
'exc_traceback'. These always travel together.
- tstate->curexc_ZZZ is the "hot" exception that is set by
PyErr_SetString(), cleared by PyErr_Clear(), and so on.
- Once an exception is caught by an except clause, it is transferred
from tstate->curexc_ZZZ to tstate->exc_ZZZ, from which sys.exc_info()
can pick it up. This is the primary task of set_exc_info().
- Now let me explain the complicated dance with frame->f_exc_ZZZ.
Long ago, when none of this existed, there were just a few globals:
one set corresponding to the "hot" exception, and one set
corresponding to sys.exc_ZZZ. (Actually, the latter weren't C
globals; they were simply stored as sys.exc_ZZZ. For backwards
compatibility, they still are!) The problem was that in code like
this:
try:
"something that may fail"
except "some exception":
"do something else first"
"print the exception from sys.exc_ZZZ."
if "do something else first" invoked something that raised and caught
an exception, sys.exc_ZZZ were overwritten. That was a frequent
cause of subtle bugs. I fixed this by changing the semantics as
follows:
- Within one frame, sys.exc_ZZZ will hold the last exception caught
*in that frame*.
- But initially, and as long as no exception is caught in a given
frame, sys.exc_ZZZ will hold the last exception caught in the
previous frame (or the frame before that, etc.).
The first bullet fixed the bug in the above example. The second
bullet was for backwards compatibility: it was (and is) common to
have a function that is called when an exception is caught, and to
have that function access the caught exception via sys.exc_ZZZ.
(Example: traceback.print_exc()).
At the same time I fixed the problem that sys.exc_ZZZ weren't
thread-safe, by introducing sys.exc_info() which gets it from tstate;
but that's really a separate improvement.
The reset_exc_info() function in ceval.c restores the tstate->exc_ZZZ
variables to what they were before the current frame was called. The
set_exc_info() function saves them on the frame so that
reset_exc_info() can restore them. The invariant is that
frame->f_exc_ZZZ is NULL iff the current frame never caught an
exception (where "catching" an exception applies only to successful
except clauses); and if the current frame ever caught an exception,
frame->f_exc_ZZZ is the exception that was stored in tstate->exc_ZZZ
at the start of the current frame.
*/
static void
set_exc_info(PyThreadState *tstate,
PyObject *type, PyObject *value, PyObject *tb)
{
PyFrameObject *frame;
PyObject *tmp_type, *tmp_value, *tmp_tb;
frame = tstate->frame;
if (frame->f_exc_type == NULL) {
/* This frame didn't catch an exception before */
/* Save previous exception of this thread in this frame */
if (tstate->exc_type == NULL) {
Py_INCREF(Py_None);
tstate->exc_type = Py_None;
}
tmp_type = frame->f_exc_type;
tmp_value = frame->f_exc_value;
tmp_tb = frame->f_exc_traceback;
Py_XINCREF(tstate->exc_type);
Py_XINCREF(tstate->exc_value);
Py_XINCREF(tstate->exc_traceback);
frame->f_exc_type = tstate->exc_type;
frame->f_exc_value = tstate->exc_value;
frame->f_exc_traceback = tstate->exc_traceback;
Py_XDECREF(tmp_type);
Py_XDECREF(tmp_value);
Py_XDECREF(tmp_tb);
}
/* Set new exception for this thread */
tmp_type = tstate->exc_type;
tmp_value = tstate->exc_value;
tmp_tb = tstate->exc_traceback;
Py_XINCREF(type);
Py_XINCREF(value);
Py_XINCREF(tb);
tstate->exc_type = type;
tstate->exc_value = value;
tstate->exc_traceback = tb;
Py_XDECREF(tmp_type);
Py_XDECREF(tmp_value);
Py_XDECREF(tmp_tb);
/* For b/w compatibility */
PySys_SetObject("exc_type", type);
PySys_SetObject("exc_value", value);
PySys_SetObject("exc_traceback", tb);
}
static void
reset_exc_info(PyThreadState *tstate)
{
PyFrameObject *frame;
PyObject *tmp_type, *tmp_value, *tmp_tb;
frame = tstate->frame;
if (frame->f_exc_type != NULL) {
/* This frame caught an exception */
tmp_type = tstate->exc_type;
tmp_value = tstate->exc_value;
tmp_tb = tstate->exc_traceback;
Py_XINCREF(frame->f_exc_type);
Py_XINCREF(frame->f_exc_value);
Py_XINCREF(frame->f_exc_traceback);
tstate->exc_type = frame->f_exc_type;
tstate->exc_value = frame->f_exc_value;
tstate->exc_traceback = frame->f_exc_traceback;
Py_XDECREF(tmp_type);
Py_XDECREF(tmp_value);
Py_XDECREF(tmp_tb);
/* For b/w compatibility */
PySys_SetObject("exc_type", frame->f_exc_type);
PySys_SetObject("exc_value", frame->f_exc_value);
PySys_SetObject("exc_traceback", frame->f_exc_traceback);
}
tmp_type = frame->f_exc_type;
tmp_value = frame->f_exc_value;
tmp_tb = frame->f_exc_traceback;
frame->f_exc_type = NULL;
frame->f_exc_value = NULL;
frame->f_exc_traceback = NULL;
Py_XDECREF(tmp_type);
Py_XDECREF(tmp_value);
Py_XDECREF(tmp_tb);
}
/* Logic for the raise statement (too complicated for inlining).
This *consumes* a reference count to each of its arguments. */
static enum why_code
do_raise(PyObject *type, PyObject *value, PyObject *tb)
{
if (type == NULL) {
/* Reraise */
PyThreadState *tstate = PyThreadState_GET();
type = tstate->exc_type == NULL ? Py_None : tstate->exc_type;
value = tstate->exc_value;
tb = tstate->exc_traceback;
Py_XINCREF(type);
Py_XINCREF(value);
Py_XINCREF(tb);
}
/* We support the following forms of raise:
raise <class>, <classinstance>
raise <class>, <argument tuple>
raise <class>, None
raise <class>, <argument>
raise <classinstance>, None
raise <string>, <object>
raise <string>, None
An omitted second argument is the same as None.
In addition, raise <tuple>, <anything> is the same as
raising the tuple's first item (and it better have one!);
this rule is applied recursively.
Finally, an optional third argument can be supplied, which
gives the traceback to be substituted (useful when
re-raising an exception after examining it). */
/* First, check the traceback argument, replacing None with
NULL. */
if (tb == Py_None) {
Py_DECREF(tb);
tb = NULL;
}
else if (tb != NULL && !PyTraceBack_Check(tb)) {
PyErr_SetString(PyExc_TypeError,
"raise: arg 3 must be a traceback or None");
goto raise_error;
}
/* Next, replace a missing value with None */
if (value == NULL) {
value = Py_None;
Py_INCREF(value);
}
/* Next, repeatedly, replace a tuple exception with its first item */
while (PyTuple_Check(type) && PyTuple_Size(type) > 0) {
PyObject *tmp = type;
type = PyTuple_GET_ITEM(type, 0);
Py_INCREF(type);
Py_DECREF(tmp);
}
if (PyString_CheckExact(type))
/* Raising builtin string is deprecated but still allowed --
* do nothing. Raising an instance of a new-style str
* subclass is right out. */
PyErr_Warn(PyExc_PendingDeprecationWarning,
"raising a string exception is deprecated");
else if (PyClass_Check(type))
PyErr_NormalizeException(&type, &value, &tb);
else if (PyInstance_Check(type)) {
/* Raising an instance. The value should be a dummy. */
if (value != Py_None) {
PyErr_SetString(PyExc_TypeError,
"instance exception may not have a separate value");
goto raise_error;
}
else {
/* Normalize to raise <class>, <instance> */
Py_DECREF(value);
value = type;
type = (PyObject*) ((PyInstanceObject*)type)->in_class;
Py_INCREF(type);
}
}
else {
/* Not something you can raise. You get an exception
anyway, just not what you specified :-) */
PyErr_Format(PyExc_TypeError,
"exceptions must be classes, instances, or "
"strings (deprecated), not %s",
type->ob_type->tp_name);
goto raise_error;
}
PyErr_Restore(type, value, tb);
if (tb == NULL)
return WHY_EXCEPTION;
else
return WHY_RERAISE;
raise_error:
Py_XDECREF(value);
Py_XDECREF(type);
Py_XDECREF(tb);
return WHY_EXCEPTION;
}
/* Iterate v argcnt times and store the results on the stack (via decreasing
sp). Return 1 for success, 0 if error. */
static int
unpack_iterable(PyObject *v, int argcnt, PyObject **sp)
{
int i = 0;
PyObject *it; /* iter(v) */
PyObject *w;
assert(v != NULL);
it = PyObject_GetIter(v);
if (it == NULL)
goto Error;
for (; i < argcnt; i++) {
w = PyIter_Next(it);
if (w == NULL) {
/* Iterator done, via error or exhaustion. */
if (!PyErr_Occurred()) {
PyErr_Format(PyExc_ValueError,
"need more than %d value%s to unpack",
i, i == 1 ? "" : "s");
}
goto Error;
}
*--sp = w;
}
/* We better have exhausted the iterator now. */
w = PyIter_Next(it);
if (w == NULL) {
if (PyErr_Occurred())
goto Error;
Py_DECREF(it);
return 1;
}
Py_DECREF(w);
PyErr_SetString(PyExc_ValueError, "too many values to unpack");
/* fall through */
Error:
for (; i > 0; i--, sp++)
Py_DECREF(*sp);
Py_XDECREF(it);
return 0;
}
#ifdef LLTRACE
static int
prtrace(PyObject *v, char *str)
{
printf("%s ", str);
if (PyObject_Print(v, stdout, 0) != 0)
PyErr_Clear(); /* Don't know what else to do */
printf("\n");
return 1;
}
#endif
static void
call_exc_trace(Py_tracefunc func, PyObject *self, PyFrameObject *f)
{
PyObject *type, *value, *traceback, *arg;
int err;
PyErr_Fetch(&type, &value, &traceback);
if (value == NULL) {
value = Py_None;
Py_INCREF(value);
}
arg = PyTuple_Pack(3, type, value, traceback);
if (arg == NULL) {
PyErr_Restore(type, value, traceback);
return;
}
err = call_trace(func, self, f, PyTrace_EXCEPTION, arg);
Py_DECREF(arg);
if (err == 0)
PyErr_Restore(type, value, traceback);
else {
Py_XDECREF(type);
Py_XDECREF(value);
Py_XDECREF(traceback);
}
}
static void
call_trace_protected(Py_tracefunc func, PyObject *obj, PyFrameObject *frame,
int what)
{
PyObject *type, *value, *traceback;
int err;
PyErr_Fetch(&type, &value, &traceback);
err = call_trace(func, obj, frame, what, NULL);
if (err == 0)
PyErr_Restore(type, value, traceback);
else {
Py_XDECREF(type);
Py_XDECREF(value);
Py_XDECREF(traceback);
}
}
static int
call_trace(Py_tracefunc func, PyObject *obj, PyFrameObject *frame,
int what, PyObject *arg)
{
register PyThreadState *tstate = frame->f_tstate;
int result;
if (tstate->tracing)
return 0;
tstate->tracing++;
tstate->use_tracing = 0;
result = func(obj, frame, what, arg);
tstate->use_tracing = ((tstate->c_tracefunc != NULL)
|| (tstate->c_profilefunc != NULL));
tstate->tracing--;
return result;
}
PyObject *
_PyEval_CallTracing(PyObject *func, PyObject *args)
{
PyFrameObject *frame = PyEval_GetFrame();
PyThreadState *tstate = frame->f_tstate;
int save_tracing = tstate->tracing;
int save_use_tracing = tstate->use_tracing;
PyObject *result;
tstate->tracing = 0;
tstate->use_tracing = ((tstate->c_tracefunc != NULL)
|| (tstate->c_profilefunc != NULL));
result = PyObject_Call(func, args, NULL);
tstate->tracing = save_tracing;
tstate->use_tracing = save_use_tracing;
return result;
}
static int
maybe_call_line_trace(Py_tracefunc func, PyObject *obj,
PyFrameObject *frame, int *instr_lb, int *instr_ub,
int *instr_prev)
{
/* The theory of SET_LINENO-less tracing.
In a nutshell, we use the co_lnotab field of the code object
to tell when execution has moved onto a different line.
As mentioned above, the basic idea is so set things up so
that
*instr_lb <= frame->f_lasti < *instr_ub
is true so long as execution does not change lines.
This is all fairly simple. Digging the information out of
co_lnotab takes some work, but is conceptually clear.
Somewhat harder to explain is why we don't *always* call the
line trace function when the above test fails.
Consider this code:
1: def f(a):
2: if a:
3: print 1
4: else:
5: print 2
which compiles to this:
2 0 LOAD_FAST 0 (a)
3 JUMP_IF_FALSE 9 (to 15)
6 POP_TOP
3 7 LOAD_CONST 1 (1)
10 PRINT_ITEM
11 PRINT_NEWLINE
12 JUMP_FORWARD 6 (to 21)
>> 15 POP_TOP
5 16 LOAD_CONST 2 (2)
19 PRINT_ITEM
20 PRINT_NEWLINE
>> 21 LOAD_CONST 0 (None)
24 RETURN_VALUE
If 'a' is false, execution will jump to instruction at offset
15 and the co_lnotab will claim that execution has moved to
line 3. This is at best misleading. In this case we could
associate the POP_TOP with line 4, but that doesn't make
sense in all cases (I think).
What we do is only call the line trace function if the co_lnotab
indicates we have jumped to the *start* of a line, i.e. if the
current instruction offset matches the offset given for the
start of a line by the co_lnotab.
This also takes care of the situation where 'a' is true.
Execution will jump from instruction offset 12 to offset 21.
Then the co_lnotab would imply that execution has moved to line
5, which is again misleading.
Why do we set f_lineno when tracing? Well, consider the code
above when 'a' is true. If stepping through this with 'n' in
pdb, you would stop at line 1 with a "call" type event, then
line events on lines 2 and 3, then a "return" type event -- but
you would be shown line 5 during this event. This is a change
from the behaviour in 2.2 and before, and I've found it
confusing in practice. By setting and using f_lineno when
tracing, one can report a line number different from that
suggested by f_lasti on this one occasion where it's desirable.
*/
int result = 0;
if ((frame->f_lasti < *instr_lb || frame->f_lasti >= *instr_ub)) {
PyCodeObject* co = frame->f_code;
int size, addr, line;
unsigned char* p;
size = PyString_GET_SIZE(co->co_lnotab) / 2;
p = (unsigned char*)PyString_AS_STRING(co->co_lnotab);
addr = 0;
line = co->co_firstlineno;
/* possible optimization: if f->f_lasti == instr_ub
(likely to be a common case) then we already know
instr_lb -- if we stored the matching value of p
somwhere we could skip the first while loop. */
/* see comments in compile.c for the description of
co_lnotab. A point to remember: increments to p
should come in pairs -- although we don't care about
the line increments here, treating them as byte
increments gets confusing, to say the least. */
while (size > 0) {
if (addr + *p > frame->f_lasti)
break;
addr += *p++;
if (*p) *instr_lb = addr;
line += *p++;
--size;
}
if (addr == frame->f_lasti) {
frame->f_lineno = line;
result = call_trace(func, obj, frame,
PyTrace_LINE, Py_None);
}
if (size > 0) {
while (size--) {
addr += *p++;
if (*p++)
break;
}
*instr_ub = addr;
}
else {
*instr_ub = INT_MAX;
}
}
else if (frame->f_lasti <= *instr_prev) {
/* jumping back in the same line forces a trace event */
result = call_trace(func, obj, frame,
PyTrace_LINE, Py_None);
}
*instr_prev = frame->f_lasti;
return result;
}
void
PyEval_SetProfile(Py_tracefunc func, PyObject *arg)
{
PyThreadState *tstate = PyThreadState_GET();
PyObject *temp = tstate->c_profileobj;
Py_XINCREF(arg);
tstate->c_profilefunc = NULL;
tstate->c_profileobj = NULL;
tstate->use_tracing = tstate->c_tracefunc != NULL;
Py_XDECREF(temp);
tstate->c_profilefunc = func;
tstate->c_profileobj = arg;
tstate->use_tracing = (func != NULL) || (tstate->c_tracefunc != NULL);
}
void
PyEval_SetTrace(Py_tracefunc func, PyObject *arg)
{
PyThreadState *tstate = PyThreadState_GET();
PyObject *temp = tstate->c_traceobj;
Py_XINCREF(arg);
tstate->c_tracefunc = NULL;
tstate->c_traceobj = NULL;
tstate->use_tracing = tstate->c_profilefunc != NULL;
Py_XDECREF(temp);
tstate->c_tracefunc = func;
tstate->c_traceobj = arg;
tstate->use_tracing = ((func != NULL)
|| (tstate->c_profilefunc != NULL));
}
PyObject *
PyEval_GetBuiltins(void)
{
PyFrameObject *current_frame = PyEval_GetFrame();
if (current_frame == NULL)
return PyThreadState_GET()->interp->builtins;
else
return current_frame->f_builtins;
}
PyObject *
PyEval_GetLocals(void)
{
PyFrameObject *current_frame = PyEval_GetFrame();
if (current_frame == NULL)
return NULL;
PyFrame_FastToLocals(current_frame);
return current_frame->f_locals;
}
PyObject *
PyEval_GetGlobals(void)
{
PyFrameObject *current_frame = PyEval_GetFrame();
if (current_frame == NULL)
return NULL;
else
return current_frame->f_globals;
}
PyFrameObject *
PyEval_GetFrame(void)
{
PyThreadState *tstate = PyThreadState_GET();
return _PyThreadState_GetFrame(tstate);
}
int
PyEval_GetRestricted(void)
{
PyFrameObject *current_frame = PyEval_GetFrame();
return current_frame == NULL ? 0 : current_frame->f_restricted;
}
int
PyEval_MergeCompilerFlags(PyCompilerFlags *cf)
{
PyFrameObject *current_frame = PyEval_GetFrame();
int result = cf->cf_flags != 0;
if (current_frame != NULL) {
const int codeflags = current_frame->f_code->co_flags;
const int compilerflags = codeflags & PyCF_MASK;
if (compilerflags) {
result = 1;
cf->cf_flags |= compilerflags;
}
#if 0 /* future keyword */
if (codeflags & CO_GENERATOR_ALLOWED) {
result = 1;
cf->cf_flags |= CO_GENERATOR_ALLOWED;
}
#endif
}
return result;
}
int
Py_FlushLine(void)
{
PyObject *f = PySys_GetObject("stdout");
if (f == NULL)
return 0;
if (!PyFile_SoftSpace(f, 0))
return 0;
return PyFile_WriteString("\n", f);
}
/* External interface to call any callable object.
The arg must be a tuple or NULL. */
#undef PyEval_CallObject
/* for backward compatibility: export this interface */
PyObject *
PyEval_CallObject(PyObject *func, PyObject *arg)
{
return PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL);
}
#define PyEval_CallObject(func,arg) \
PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL)
PyObject *
PyEval_CallObjectWithKeywords(PyObject *func, PyObject *arg, PyObject *kw)
{
PyObject *result;
if (arg == NULL)
arg = PyTuple_New(0);
else if (!PyTuple_Check(arg)) {
PyErr_SetString(PyExc_TypeError,
"argument list must be a tuple");
return NULL;
}
else
Py_INCREF(arg);
if (kw != NULL && !PyDict_Check(kw)) {
PyErr_SetString(PyExc_TypeError,
"keyword list must be a dictionary");
Py_DECREF(arg);
return NULL;
}
result = PyObject_Call(func, arg, kw);
Py_DECREF(arg);
return result;
}
char *
PyEval_GetFuncName(PyObject *func)
{
if (PyMethod_Check(func))
return PyEval_GetFuncName(PyMethod_GET_FUNCTION(func));
else if (PyFunction_Check(func))
return PyString_AsString(((PyFunctionObject*)func)->func_name);
else if (PyCFunction_Check(func))
return ((PyCFunctionObject*)func)->m_ml->ml_name;
else if (PyClass_Check(func))
return PyString_AsString(((PyClassObject*)func)->cl_name);
else if (PyInstance_Check(func)) {
return PyString_AsString(
((PyInstanceObject*)func)->in_class->cl_name);
} else {
return func->ob_type->tp_name;
}
}
char *
PyEval_GetFuncDesc(PyObject *func)
{
if (PyMethod_Check(func))
return "()";
else if (PyFunction_Check(func))
return "()";
else if (PyCFunction_Check(func))
return "()";
else if (PyClass_Check(func))
return " constructor";
else if (PyInstance_Check(func)) {
return " instance";
} else {
return " object";
}
}
#define EXT_POP(STACK_POINTER) (*--(STACK_POINTER))
static void
err_args(PyObject *func, int flags, int nargs)
{
if (flags & METH_NOARGS)
PyErr_Format(PyExc_TypeError,
"%.200s() takes no arguments (%d given)",
((PyCFunctionObject *)func)->m_ml->ml_name,
nargs);
else
PyErr_Format(PyExc_TypeError,
"%.200s() takes exactly one argument (%d given)",
((PyCFunctionObject *)func)->m_ml->ml_name,
nargs);
}
#define BEGIN_C_TRACE \
if (tstate->use_tracing) { \
if (tstate->c_profilefunc != NULL) { \
PyObject *func_name = \
PyString_FromString (((PyCFunctionObject *) \
func)->m_ml->ml_name); \
are_tracing = 1; \
if (call_trace(tstate->c_profilefunc, \
tstate->c_profileobj, \
tstate->frame, PyTrace_C_CALL, \
func_name)) \
{ return NULL; } \
Py_DECREF (func_name); \
} \
}
#define END_C_TRACE \
if (tstate->use_tracing && are_tracing) { \
if (tstate->c_profilefunc != NULL) { \
if (x == NULL) { \
if (call_trace (tstate->c_profilefunc, \
tstate->c_profileobj, \
tstate->frame, PyTrace_C_EXCEPTION, \
NULL)) \
{ return NULL; } \
} else { \
if (call_trace(tstate->c_profilefunc, \
tstate->c_profileobj, \
tstate->frame, PyTrace_C_RETURN, \
NULL)) \
{ return NULL; } \
} \
} \
}
static PyObject *
call_function(PyObject ***pp_stack, int oparg)
{
int na = oparg & 0xff;
int nk = (oparg>>8) & 0xff;
int n = na + 2 * nk;
PyObject **pfunc = (*pp_stack) - n - 1;
PyObject *func = *pfunc;
PyObject *x, *w;
int are_tracing = 0;
PyThreadState *tstate = PyThreadState_GET();
/* Always dispatch PyCFunction first, because these are
presumed to be the most frequent callable object.
*/
if (PyCFunction_Check(func) && nk == 0) {
int flags = PyCFunction_GET_FLAGS(func);
PCALL(PCALL_CFUNCTION);
if (flags & (METH_NOARGS | METH_O)) {
PyCFunction meth = PyCFunction_GET_FUNCTION(func);
PyObject *self = PyCFunction_GET_SELF(func);
if (flags & METH_NOARGS && na == 0) {
BEGIN_C_TRACE
x = (*meth)(self, NULL);
END_C_TRACE
}
else if (flags & METH_O && na == 1) {
PyObject *arg = EXT_POP(*pp_stack);
BEGIN_C_TRACE
x = (*meth)(self, arg);
END_C_TRACE
Py_DECREF(arg);
}
else {
err_args(func, flags, na);
x = NULL;
}
}
else {
PyObject *callargs;
callargs = load_args(pp_stack, na);
BEGIN_C_TRACE
x = PyCFunction_Call(func, callargs, NULL);
END_C_TRACE
Py_XDECREF(callargs);
}
} else {
if (PyMethod_Check(func) && PyMethod_GET_SELF(func) != NULL) {
/* optimize access to bound methods */
PyObject *self = PyMethod_GET_SELF(func);
PCALL(PCALL_METHOD);
PCALL(PCALL_BOUND_METHOD);
Py_INCREF(self);
func = PyMethod_GET_FUNCTION(func);
Py_INCREF(func);
Py_DECREF(*pfunc);
*pfunc = self;
na++;
n++;
} else
Py_INCREF(func);
if (PyFunction_Check(func))
x = fast_function(func, pp_stack, n, na, nk);
else
x = do_call(func, pp_stack, na, nk);
Py_DECREF(func);
}
/* What does this do? */
while ((*pp_stack) > pfunc) {
w = EXT_POP(*pp_stack);
Py_DECREF(w);
PCALL(PCALL_POP);
}
return x;
}
/* The fast_function() function optimize calls for which no argument
tuple is necessary; the objects are passed directly from the stack.
For the simplest case -- a function that takes only positional
arguments and is called with only positional arguments -- it
inlines the most primitive frame setup code from
PyEval_EvalCodeEx(), which vastly reduces the checks that must be
done before evaluating the frame.
*/
static PyObject *
fast_function(PyObject *func, PyObject ***pp_stack, int n, int na, int nk)
{
PyCodeObject *co = (PyCodeObject *)PyFunction_GET_CODE(func);
PyObject *globals = PyFunction_GET_GLOBALS(func);
PyObject *argdefs = PyFunction_GET_DEFAULTS(func);
PyObject **d = NULL;
int nd = 0;
PCALL(PCALL_FUNCTION);
PCALL(PCALL_FAST_FUNCTION);
if (argdefs == NULL && co->co_argcount == n && nk==0 &&
co->co_flags == (CO_OPTIMIZED | CO_NEWLOCALS | CO_NOFREE)) {
PyFrameObject *f;
PyObject *retval = NULL;
PyThreadState *tstate = PyThreadState_GET();
PyObject **fastlocals, **stack;
int i;
PCALL(PCALL_FASTER_FUNCTION);
assert(globals != NULL);
/* XXX Perhaps we should create a specialized
PyFrame_New() that doesn't take locals, but does
take builtins without sanity checking them.
*/
f = PyFrame_New(tstate, co, globals, NULL);
if (f == NULL)
return NULL;
fastlocals = f->f_localsplus;
stack = (*pp_stack) - n;
for (i = 0; i < n; i++) {
Py_INCREF(*stack);
fastlocals[i] = *stack++;
}
retval = eval_frame(f);
assert(tstate != NULL);
++tstate->recursion_depth;
Py_DECREF(f);
--tstate->recursion_depth;
return retval;
}
if (argdefs != NULL) {
d = &PyTuple_GET_ITEM(argdefs, 0);
nd = ((PyTupleObject *)argdefs)->ob_size;
}
return PyEval_EvalCodeEx(co, globals,
(PyObject *)NULL, (*pp_stack)-n, na,
(*pp_stack)-2*nk, nk, d, nd,
PyFunction_GET_CLOSURE(func));
}
static PyObject *
update_keyword_args(PyObject *orig_kwdict, int nk, PyObject ***pp_stack,
PyObject *func)
{
PyObject *kwdict = NULL;
if (orig_kwdict == NULL)
kwdict = PyDict_New();
else {
kwdict = PyDict_Copy(orig_kwdict);
Py_DECREF(orig_kwdict);
}
if (kwdict == NULL)
return NULL;
while (nk--) {
int err;
PyObject *value = EXT_POP(*pp_stack);
PyObject *key = EXT_POP(*pp_stack);
if (PyDict_GetItem(kwdict, key) != NULL) {
PyErr_Format(PyExc_TypeError,
"%.200s%s got multiple values "
"for keyword argument '%.200s'",
PyEval_GetFuncName(func),
PyEval_GetFuncDesc(func),
PyString_AsString(key));
Py_DECREF(key);
Py_DECREF(value);
Py_DECREF(kwdict);
return NULL;
}
err = PyDict_SetItem(kwdict, key, value);
Py_DECREF(key);
Py_DECREF(value);
if (err) {
Py_DECREF(kwdict);
return NULL;
}
}
return kwdict;
}
static PyObject *
update_star_args(int nstack, int nstar, PyObject *stararg,
PyObject ***pp_stack)
{
PyObject *callargs, *w;
callargs = PyTuple_New(nstack + nstar);
if (callargs == NULL) {
return NULL;
}
if (nstar) {
int i;
for (i = 0; i < nstar; i++) {
PyObject *a = PyTuple_GET_ITEM(stararg, i);
Py_INCREF(a);
PyTuple_SET_ITEM(callargs, nstack + i, a);
}
}
while (nstack--) {
w = EXT_POP(*pp_stack);
PyTuple_SET_ITEM(callargs, nstack, w);
}
return callargs;
}
static PyObject *
load_args(PyObject ***pp_stack, int na)
{
PyObject *args = PyTuple_New(na);
PyObject *w;
if (args == NULL)
return NULL;
while (na--) {
w = EXT_POP(*pp_stack);
PyTuple_SET_ITEM(args, na, w);
}
return args;
}
static PyObject *
do_call(PyObject *func, PyObject ***pp_stack, int na, int nk)
{
PyObject *callargs = NULL;
PyObject *kwdict = NULL;
PyObject *result = NULL;
if (nk > 0) {
kwdict = update_keyword_args(NULL, nk, pp_stack, func);
if (kwdict == NULL)
goto call_fail;
}
callargs = load_args(pp_stack, na);
if (callargs == NULL)
goto call_fail;
#ifdef CALL_PROFILE
/* At this point, we have to look at the type of func to
update the call stats properly. Do it here so as to avoid
exposing the call stats machinery outside ceval.c
*/
if (PyFunction_Check(func))
PCALL(PCALL_FUNCTION);
else if (PyMethod_Check(func))
PCALL(PCALL_METHOD);
else if (PyType_Check(func))
PCALL(PCALL_TYPE);
else
PCALL(PCALL_OTHER);
#endif
result = PyObject_Call(func, callargs, kwdict);
call_fail:
Py_XDECREF(callargs);
Py_XDECREF(kwdict);
return result;
}
static PyObject *
ext_do_call(PyObject *func, PyObject ***pp_stack, int flags, int na, int nk)
{
int nstar = 0;
PyObject *callargs = NULL;
PyObject *stararg = NULL;
PyObject *kwdict = NULL;
PyObject *result = NULL;
if (flags & CALL_FLAG_KW) {
kwdict = EXT_POP(*pp_stack);
if (!(kwdict && PyDict_Check(kwdict))) {
PyErr_Format(PyExc_TypeError,
"%s%s argument after ** "
"must be a dictionary",
PyEval_GetFuncName(func),
PyEval_GetFuncDesc(func));
goto ext_call_fail;
}
}
if (flags & CALL_FLAG_VAR) {
stararg = EXT_POP(*pp_stack);
if (!PyTuple_Check(stararg)) {
PyObject *t = NULL;
t = PySequence_Tuple(stararg);
if (t == NULL) {
if (PyErr_ExceptionMatches(PyExc_TypeError)) {
PyErr_Format(PyExc_TypeError,
"%s%s argument after * "
"must be a sequence",
PyEval_GetFuncName(func),
PyEval_GetFuncDesc(func));
}
goto ext_call_fail;
}
Py_DECREF(stararg);
stararg = t;
}
nstar = PyTuple_GET_SIZE(stararg);
}
if (nk > 0) {
kwdict = update_keyword_args(kwdict, nk, pp_stack, func);
if (kwdict == NULL)
goto ext_call_fail;
}
callargs = update_star_args(na, nstar, stararg, pp_stack);
if (callargs == NULL)
goto ext_call_fail;
#ifdef CALL_PROFILE
/* At this point, we have to look at the type of func to
update the call stats properly. Do it here so as to avoid
exposing the call stats machinery outside ceval.c
*/
if (PyFunction_Check(func))
PCALL(PCALL_FUNCTION);
else if (PyMethod_Check(func))
PCALL(PCALL_METHOD);
else if (PyType_Check(func))
PCALL(PCALL_TYPE);
else
PCALL(PCALL_OTHER);
#endif
result = PyObject_Call(func, callargs, kwdict);
ext_call_fail:
Py_XDECREF(callargs);
Py_XDECREF(kwdict);
Py_XDECREF(stararg);
return result;
}
#define SLICE_ERROR_MSG \
"standard sequence type does not support step size other than one"
/* Extract a slice index from a PyInt or PyLong, and store in *pi.
Silently reduce values larger than INT_MAX to INT_MAX, and silently
boost values less than -INT_MAX to 0. Return 0 on error, 1 on success.
*/
/* Note: If v is NULL, return success without storing into *pi. This
is because_PyEval_SliceIndex() is called by apply_slice(), which can be
called by the SLICE opcode with v and/or w equal to NULL.
*/
int
_PyEval_SliceIndex(PyObject *v, int *pi)
{
if (v != NULL) {
long x;
if (PyInt_Check(v)) {
x = PyInt_AsLong(v);
} else if (PyLong_Check(v)) {
x = PyLong_AsLong(v);
if (x==-1 && PyErr_Occurred()) {
PyObject *long_zero;
int cmp;
if (!PyErr_ExceptionMatches(
PyExc_OverflowError)) {
/* It's not an overflow error, so just
signal an error */
return 0;
}
/* Clear the OverflowError */
PyErr_Clear();
/* It's an overflow error, so we need to
check the sign of the long integer,
set the value to INT_MAX or -INT_MAX,
and clear the error. */
/* Create a long integer with a value of 0 */
long_zero = PyLong_FromLong(0L);
if (long_zero == NULL)
return 0;
/* Check sign */
cmp = PyObject_RichCompareBool(v, long_zero,
Py_GT);
Py_DECREF(long_zero);
if (cmp < 0)
return 0;
else if (cmp)
x = INT_MAX;
else
x = -INT_MAX;
}
} else {
PyErr_SetString(PyExc_TypeError,
"slice indices must be integers");
return 0;
}
/* Truncate -- very long indices are truncated anyway */
if (x > INT_MAX)
x = INT_MAX;
else if (x < -INT_MAX)
x = -INT_MAX;
*pi = x;
}
return 1;
}
#undef ISINT
#define ISINT(x) ((x) == NULL || PyInt_Check(x) || PyLong_Check(x))
static PyObject *
apply_slice(PyObject *u, PyObject *v, PyObject *w) /* return u[v:w] */
{
PyTypeObject *tp = u->ob_type;
PySequenceMethods *sq = tp->tp_as_sequence;
if (sq && sq->sq_slice && ISINT(v) && ISINT(w)) {
int ilow = 0, ihigh = INT_MAX;
if (!_PyEval_SliceIndex(v, &ilow))
return NULL;
if (!_PyEval_SliceIndex(w, &ihigh))
return NULL;
return PySequence_GetSlice(u, ilow, ihigh);
}
else {
PyObject *slice = PySlice_New(v, w, NULL);
if (slice != NULL) {
PyObject *res = PyObject_GetItem(u, slice);
Py_DECREF(slice);
return res;
}
else
return NULL;
}
}
static int
assign_slice(PyObject *u, PyObject *v, PyObject *w, PyObject *x)
/* u[v:w] = x */
{
PyTypeObject *tp = u->ob_type;
PySequenceMethods *sq = tp->tp_as_sequence;
if (sq && sq->sq_slice && ISINT(v) && ISINT(w)) {
int ilow = 0, ihigh = INT_MAX;
if (!_PyEval_SliceIndex(v, &ilow))
return -1;
if (!_PyEval_SliceIndex(w, &ihigh))
return -1;
if (x == NULL)
return PySequence_DelSlice(u, ilow, ihigh);
else
return PySequence_SetSlice(u, ilow, ihigh, x);
}
else {
PyObject *slice = PySlice_New(v, w, NULL);
if (slice != NULL) {
int res;
if (x != NULL)
res = PyObject_SetItem(u, slice, x);
else
res = PyObject_DelItem(u, slice);
Py_DECREF(slice);
return res;
}
else
return -1;
}
}
static PyObject *
cmp_outcome(int op, register PyObject *v, register PyObject *w)
{
int res = 0;
switch (op) {
case PyCmp_IS:
res = (v == w);
break;
case PyCmp_IS_NOT:
res = (v != w);
break;
case PyCmp_IN:
res = PySequence_Contains(w, v);
if (res < 0)
return NULL;
break;
case PyCmp_NOT_IN:
res = PySequence_Contains(w, v);
if (res < 0)
return NULL;
res = !res;
break;
case PyCmp_EXC_MATCH:
res = PyErr_GivenExceptionMatches(v, w);
break;
default:
return PyObject_RichCompare(v, w, op);
}
v = res ? Py_True : Py_False;
Py_INCREF(v);
return v;
}
static PyObject *
import_from(PyObject *v, PyObject *name)
{
PyObject *x;
x = PyObject_GetAttr(v, name);
if (x == NULL && PyErr_ExceptionMatches(PyExc_AttributeError)) {
PyErr_Format(PyExc_ImportError,
"cannot import name %.230s",
PyString_AsString(name));
}
return x;
}
static int
import_all_from(PyObject *locals, PyObject *v)
{
PyObject *all = PyObject_GetAttrString(v, "__all__");
PyObject *dict, *name, *value;
int skip_leading_underscores = 0;
int pos, err;
if (all == NULL) {
if (!PyErr_ExceptionMatches(PyExc_AttributeError))
return -1; /* Unexpected error */
PyErr_Clear();
dict = PyObject_GetAttrString(v, "__dict__");
if (dict == NULL) {
if (!PyErr_ExceptionMatches(PyExc_AttributeError))
return -1;
PyErr_SetString(PyExc_ImportError,
"from-import-* object has no __dict__ and no __all__");
return -1;
}
all = PyMapping_Keys(dict);
Py_DECREF(dict);
if (all == NULL)
return -1;
skip_leading_underscores = 1;
}
for (pos = 0, err = 0; ; pos++) {
name = PySequence_GetItem(all, pos);
if (name == NULL) {
if (!PyErr_ExceptionMatches(PyExc_IndexError))
err = -1;
else
PyErr_Clear();
break;
}
if (skip_leading_underscores &&
PyString_Check(name) &&
PyString_AS_STRING(name)[0] == '_')
{
Py_DECREF(name);
continue;
}
value = PyObject_GetAttr(v, name);
if (value == NULL)
err = -1;
else
err = PyDict_SetItem(locals, name, value);
Py_DECREF(name);
Py_XDECREF(value);
if (err != 0)
break;
}
Py_DECREF(all);
return err;
}
static PyObject *
build_class(PyObject *methods, PyObject *bases, PyObject *name)
{
PyObject *metaclass = NULL, *result, *base;
if (PyDict_Check(methods))
metaclass = PyDict_GetItemString(methods, "__metaclass__");
if (metaclass != NULL)
Py_INCREF(metaclass);
else if (PyTuple_Check(bases) && PyTuple_GET_SIZE(bases) > 0) {
base = PyTuple_GET_ITEM(bases, 0);
metaclass = PyObject_GetAttrString(base, "__class__");
if (metaclass == NULL) {
PyErr_Clear();
metaclass = (PyObject *)base->ob_type;
Py_INCREF(metaclass);
}
}
else {
PyObject *g = PyEval_GetGlobals();
if (g != NULL && PyDict_Check(g))
metaclass = PyDict_GetItemString(g, "__metaclass__");
if (metaclass == NULL)
metaclass = (PyObject *) &PyClass_Type;
Py_INCREF(metaclass);
}
result = PyObject_CallFunction(metaclass, "OOO", name, bases, methods);
Py_DECREF(metaclass);
return result;
}
static int
exec_statement(PyFrameObject *f, PyObject *prog, PyObject *globals,
PyObject *locals)
{
int n;
PyObject *v;
int plain = 0;
if (PyTuple_Check(prog) && globals == Py_None && locals == Py_None &&
((n = PyTuple_Size(prog)) == 2 || n == 3)) {
/* Backward compatibility hack */
globals = PyTuple_GetItem(prog, 1);
if (n == 3)
locals = PyTuple_GetItem(prog, 2);
prog = PyTuple_GetItem(prog, 0);
}
if (globals == Py_None) {
globals = PyEval_GetGlobals();
if (locals == Py_None) {
locals = PyEval_GetLocals();
plain = 1;
}
}
else if (locals == Py_None)
locals = globals;
if (!PyString_Check(prog) &&
!PyUnicode_Check(prog) &&
!PyCode_Check(prog) &&
!PyFile_Check(prog)) {
PyErr_SetString(PyExc_TypeError,
"exec: arg 1 must be a string, file, or code object");
return -1;
}
if (!PyDict_Check(globals)) {
PyErr_SetString(PyExc_TypeError,
"exec: arg 2 must be a dictionary or None");
return -1;
}
if (!PyDict_Check(locals)) {
PyErr_SetString(PyExc_TypeError,
"exec: arg 3 must be a dictionary or None");
return -1;
}
if (PyDict_GetItemString(globals, "__builtins__") == NULL)
PyDict_SetItemString(globals, "__builtins__", f->f_builtins);
if (PyCode_Check(prog)) {
if (PyCode_GetNumFree((PyCodeObject *)prog) > 0) {
PyErr_SetString(PyExc_TypeError,
"code object passed to exec may not contain free variables");
return -1;
}
v = PyEval_EvalCode((PyCodeObject *) prog, globals, locals);
}
else if (PyFile_Check(prog)) {
FILE *fp = PyFile_AsFile(prog);
char *name = PyString_AsString(PyFile_Name(prog));
PyCompilerFlags cf;
cf.cf_flags = 0;
if (PyEval_MergeCompilerFlags(&cf))
v = PyRun_FileFlags(fp, name, Py_file_input, globals,
locals, &cf);
else
v = PyRun_File(fp, name, Py_file_input, globals,
locals);
}
else {
PyObject *tmp = NULL;
char *str;
PyCompilerFlags cf;
cf.cf_flags = 0;
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(prog)) {
tmp = PyUnicode_AsUTF8String(prog);
if (tmp == NULL)
return -1;
prog = tmp;
cf.cf_flags |= PyCF_SOURCE_IS_UTF8;
}
#endif
if (PyString_AsStringAndSize(prog, &str, NULL))
return -1;
if (PyEval_MergeCompilerFlags(&cf))
v = PyRun_StringFlags(str, Py_file_input, globals,
locals, &cf);
else
v = PyRun_String(str, Py_file_input, globals, locals);
Py_XDECREF(tmp);
}
if (plain)
PyFrame_LocalsToFast(f, 0);
if (v == NULL)
return -1;
Py_DECREF(v);
return 0;
}
static void
format_exc_check_arg(PyObject *exc, char *format_str, PyObject *obj)
{
char *obj_str;
if (!obj)
return;
obj_str = PyString_AsString(obj);
if (!obj_str)
return;
PyErr_Format(exc, format_str, obj_str);
}
#ifdef DYNAMIC_EXECUTION_PROFILE
static PyObject *
getarray(long a[256])
{
int i;
PyObject *l = PyList_New(256);
if (l == NULL) return NULL;
for (i = 0; i < 256; i++) {
PyObject *x = PyInt_FromLong(a[i]);
if (x == NULL) {
Py_DECREF(l);
return NULL;
}
PyList_SetItem(l, i, x);
}
for (i = 0; i < 256; i++)
a[i] = 0;
return l;
}
PyObject *
_Py_GetDXProfile(PyObject *self, PyObject *args)
{
#ifndef DXPAIRS
return getarray(dxp);
#else
int i;
PyObject *l = PyList_New(257);
if (l == NULL) return NULL;
for (i = 0; i < 257; i++) {
PyObject *x = getarray(dxpairs[i]);
if (x == NULL) {
Py_DECREF(l);
return NULL;
}
PyList_SetItem(l, i, x);
}
return l;
#endif
}
#endif
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