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gvanrossumgvanrossum
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Changes for slice and ellipses
1 parent 3ecebf1 commit 8861b74

6 files changed

Lines changed: 355 additions & 181 deletions

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‎Python/bltinmodule.c‎

Lines changed: 23 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -879,6 +879,28 @@ builtin_list(self, args)
879879
return NULL;
880880
}
881881

882+
883+
static PyObject *
884+
builtin_slice(self, args)
885+
PyObject *self;
886+
PyObject *args;
887+
{
888+
PyObject *start, *stop, *step;
889+
890+
start = stop = step = NULL;
891+
892+
if (!PyArg_ParseTuple(args, "O|OO:slice", &start, &stop, &step))
893+
return NULL;
894+
895+
/*This swapping of stop and start is to maintain compatibility with
896+
the range builtin.*/
897+
if (stop == NULL) {
898+
stop = start;
899+
start = NULL;
900+
}
901+
return PySlice_New(start, stop, step);
902+
}
903+
882904
static object *
883905
builtin_locals(self, args)
884906
object *self;
@@ -1514,6 +1536,7 @@ static struct methodlist builtin_methods[] = {
15141536
{"repr", builtin_repr, 1},
15151537
{"round", builtin_round, 1},
15161538
{"setattr", builtin_setattr, 1},
1539+
{"slice", builtin_slice, 1},
15171540
{"str", builtin_str, 1},
15181541
{"tuple", builtin_tuple, 1},
15191542
{"type", builtin_type, 1},

‎Python/ceval.c‎

Lines changed: 67 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -87,6 +87,7 @@ static object *apply_subscript PROTO((object *, object *));
8787
static object *loop_subscript PROTO((object *, object *));
8888
static int slice_index PROTO((object *, int, int *));
8989
static object *apply_slice PROTO((object *, object *, object *));
90+
static object *build_slice PROTO((object *, object *, object *));
9091
static int assign_subscript PROTO((object *, object *, object *));
9192
static int assign_slice PROTO((object *, object *, object *, object *));
9293
static int cmp_exception PROTO((object *, object *));
@@ -187,6 +188,8 @@ restore_thread(x)
187188
thread (the main thread) ever takes things out of the queue.
188189
*/
189190

191+
static int ticker = 0; /* main loop counter to do periodic things */
192+
190193
#define NPENDINGCALLS 32
191194
static struct {
192195
int (*func) PROTO((ANY *));
@@ -215,6 +218,7 @@ Py_AddPendingCall(func, arg)
215218
pendingcalls[i].func = func;
216219
pendingcalls[i].arg = arg;
217220
pendinglast = j;
221+
ticker = 0; /* Signal main loop */
218222
busy = 0;
219223
/* XXX End critical section */
220224
return 0;
@@ -225,11 +229,15 @@ Py_MakePendingCalls()
225229
{
226230
static int busy = 0;
227231
#ifdef WITH_THREAD
228-
if (get_thread_ident() != main_thread)
232+
if (get_thread_ident() != main_thread) {
233+
ticker = 0; /* We're not done yet */
229234
return 0;
235+
}
230236
#endif
231-
if (busy)
237+
if (busy) {
238+
ticker = 0; /* We're not done yet */
232239
return 0;
240+
}
233241
busy = 1;
234242
for (;;) {
235243
int i;
@@ -243,6 +251,7 @@ Py_MakePendingCalls()
243251
pendingfirst = (i + 1) % NPENDINGCALLS;
244252
if (func(arg) < 0) {
245253
busy = 0;
254+
ticker = 0; /* We're not done yet */
246255
return -1;
247256
}
248257
}
@@ -281,6 +290,12 @@ eval_code(co, globals, locals)
281290

282291
/* Interpreter main loop */
283292

293+
#ifndef MAX_RECURSION_DEPTH
294+
#define MAX_RECURSION_DEPTH 10000
295+
#endif
296+
297+
static int recursion_depth = 0;
298+
284299
static object *
285300
eval_code2(co, globals, locals,
286301
args, argcount, kws, kwcount, defs, defcount, owner)
@@ -355,6 +370,13 @@ eval_code2(co, globals, locals,
355370
#define SETLOCAL(i, value) do { XDECREF(GETLOCAL(i)); \
356371
GETLOCAL(i) = value; } while (0)
357372

373+
#ifdef USE_STACKCHECK
374+
if (recursion_depth%10 == 0 && PyOS_CheckStack()) {
375+
err_setstr(MemoryError, "Stack overflow");
376+
return NULL;
377+
}
378+
#endif
379+
358380
if (globals == NULL) {
359381
err_setstr(SystemError, "eval_code2: NULL globals");
360382
return NULL;
@@ -514,6 +536,14 @@ eval_code2(co, globals, locals,
514536
}
515537
}
516538

539+
if (++recursion_depth > MAX_RECURSION_DEPTH) {
540+
--recursion_depth;
541+
err_setstr(RuntimeError, "Maximum recursion depth exceeded");
542+
current_frame = f->f_back;
543+
DECREF(f);
544+
return NULL;
545+
}
546+
517547
next_instr = GETUSTRINGVALUE(f->f_code->co_code);
518548
stack_pointer = f->f_valuestack;
519549

@@ -522,22 +552,23 @@ eval_code2(co, globals, locals,
522552
x = None; /* Not a reference, just anything non-NULL */
523553

524554
for (;;) {
525-
static int ticker;
526-
527555
/* Do periodic things.
528556
Doing this every time through the loop would add
529557
too much overhead (a function call per instruction).
530-
So we do it only every Nth instruction. */
531-
532-
if (pendingfirst != pendinglast) {
533-
if (Py_MakePendingCalls() < 0) {
534-
why = WHY_EXCEPTION;
535-
goto on_error;
536-
}
537-
}
558+
So we do it only every Nth instruction.
559+
560+
The ticker is reset to zero if there are pending
561+
calls (see Py_AddPendingCalls() and
562+
Py_MakePendingCalls() above). */
538563

539564
if (--ticker < 0) {
540565
ticker = sys_checkinterval;
566+
if (pendingfirst != pendinglast) {
567+
if (Py_MakePendingCalls() < 0) {
568+
why = WHY_EXCEPTION;
569+
goto on_error;
570+
}
571+
}
541572
if (sigcheck()) {
542573
why = WHY_EXCEPTION;
543574
goto on_error;
@@ -1630,7 +1661,22 @@ eval_code2(co, globals, locals,
16301661
}
16311662
PUSH(x);
16321663
break;
1633-
1664+
1665+
case BUILD_SLICE:
1666+
if (oparg == 3)
1667+
w = POP();
1668+
else
1669+
w = NULL;
1670+
v = POP();
1671+
u = POP();
1672+
x = build_slice(u,v,w);
1673+
DECREF(u);
1674+
DECREF(v);
1675+
XDECREF(w);
1676+
PUSH(x);
1677+
break;
1678+
1679+
16341680
default:
16351681
fprintf(stderr,
16361682
"XXX lineno: %d, opcode: %d\n",
@@ -1793,6 +1839,7 @@ eval_code2(co, globals, locals,
17931839

17941840
current_frame = f->f_back;
17951841
DECREF(f);
1842+
--recursion_depth;
17961843

17971844
return retval;
17981845
}
@@ -2548,6 +2595,13 @@ slice_index(v, isize, pi)
25482595
return 0;
25492596
}
25502597

2598+
static object *
2599+
build_slice(u, v, w) /* u:v:w */
2600+
object *u, *v, *w;
2601+
{
2602+
return PySlice_New(u,v,w);
2603+
}
2604+
25512605
static object *
25522606
apply_slice(u, v, w) /* return u[v:w] */
25532607
object *u, *v, *w;

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