Issue #23517: Fix _PyTime_ObjectToDenominator()

vstinner · vstinner · commit 67edcc905d35 · 2015-09-02T10:37:46.000+02:00
* initialize numerator on overflow error ensure that numerator is smaller than
* denominator.
diff --git a/Python/pytime.c b/Python/pytime.c
@@ -60,6 +60,7 @@ _PyLong_FromTime_t(time_t t)
 #endif
 }
 
+/* Round to nearest with ties going away from zero (_PyTime_ROUND_HALF_UP). */
 static double
 _PyTime_RoundHalfUp(double x)
 {
@@ -81,32 +82,31 @@ _PyTime_DoubleToDenominator(double d, time_t *sec, long *numerator,
 
     floatpart = modf(d, &intpart);
     if (floatpart < 0) {
-        floatpart = 1.0 + floatpart;
+        floatpart += 1.0;
         intpart -= 1.0;
     }
 
     floatpart *= denominator;
     if (round == _PyTime_ROUND_HALF_UP)
         floatpart = _PyTime_RoundHalfUp(floatpart);
-    else if (round == _PyTime_ROUND_CEILING) {
+    else if (round == _PyTime_ROUND_CEILING)
         floatpart = ceil(floatpart);
-        if (floatpart >= denominator) {
-            floatpart = 0.0;
-            intpart += 1.0;
-        }
-    }
-    else {
+    else
         floatpart = floor(floatpart);
+    if (floatpart >= denominator) {
+        floatpart -= denominator;
+        intpart += 1.0;
     }
+    assert(0.0 <= floatpart && floatpart < denominator);
 
     *sec = (time_t)intpart;
+    *numerator = (long)floatpart;
+
     err = intpart - (double)*sec;
     if (err <= -1.0 || err >= 1.0) {
         error_time_t_overflow();
         return -1;
     }
-
-    *numerator = (long)floatpart;
     return 0;
 }
 
@@ -123,9 +123,9 @@ _PyTime_ObjectToDenominator(PyObject *obj, time_t *sec, long *numerator,
     }
     else {
         *sec = _PyLong_AsTime_t(obj);
+        *numerator = 0;
         if (*sec == (time_t)-1 && PyErr_Occurred())
             return -1;
-        *numerator = 0;
         return 0;
     }
 }
@@ -167,7 +167,7 @@ _PyTime_ObjectToTimespec(PyObject *obj, time_t *sec, long *nsec,
 {
     int res;
     res = _PyTime_ObjectToDenominator(obj, sec, nsec, 1e9, round);
-    assert(0 <= *nsec && *nsec < SEC_TO_NS );
+    assert(0 <= *nsec && *nsec < SEC_TO_NS);
     return res;
 }
 
@@ -177,7 +177,7 @@ _PyTime_ObjectToTimeval(PyObject *obj, time_t *sec, long *usec,
 {
     int res;
     res = _PyTime_ObjectToDenominator(obj, sec, usec, 1e6, round);
-    assert(0 <= *usec && *usec < SEC_TO_US );
+    assert(0 <= *usec && *usec < SEC_TO_US);
     return res;
 }
 
@@ -444,12 +444,11 @@ _PyTime_AsTimeval_impl(_PyTime_t t, struct timeval *tv, _PyTime_round_t round,
         tv->tv_sec += 1;
     }
 
+    assert(0 <= usec && usec < SEC_TO_US);
+    tv->tv_usec = usec;
+
     if (res && raise)
         _PyTime_overflow();
-
-    assert(0 <= usec && usec <= 999999);
-
-    tv->tv_usec = usec;
     return res;
 }
 
@@ -484,7 +483,7 @@ _PyTime_AsTimespec(_PyTime_t t, struct timespec *ts)
     }
     ts->tv_nsec = nsec;
 
-    assert(0 <= ts->tv_nsec && ts->tv_nsec <= 999999999);
+    assert(0 <= ts->tv_nsec && ts->tv_nsec < SEC_TO_NS);
     return 0;
 }
 #endif

Original file line number	Diff line number	Diff line change
`@@ -60,6 +60,7 @@ _PyLong_FromTime_t(time_t t)`
`60`	`60`	`#endif`
`61`	`61`	`}`
`62`	`62`
	`63`	`+/* Round to nearest with ties going away from zero (_PyTime_ROUND_HALF_UP). */`
`63`	`64`	`static double`
`64`	`65`	`_PyTime_RoundHalfUp(double x)`
`65`	`66`	`{`
`@@ -81,32 +82,31 @@ _PyTime_DoubleToDenominator(double d, time_t sec, long numerator,`
`81`	`82`
`82`	`83`	`floatpart = modf(d, &intpart);`
`83`	`84`	`if (floatpart < 0) {`
`84`		`- floatpart = 1.0 + floatpart;`
	`85`	`+ floatpart += 1.0;`
`85`	`86`	`intpart -= 1.0;`
`86`	`87`	`}`
`87`	`88`
`88`	`89`	`floatpart *= denominator;`
`89`	`90`	`if (round == _PyTime_ROUND_HALF_UP)`
`90`	`91`	`floatpart = _PyTime_RoundHalfUp(floatpart);`
`91`		`- else if (round == _PyTime_ROUND_CEILING) {`
	`92`	`+ else if (round == _PyTime_ROUND_CEILING)`
`92`	`93`	`floatpart = ceil(floatpart);`
`93`		`- if (floatpart >= denominator) {`
`94`		`- floatpart = 0.0;`
`95`		`- intpart += 1.0;`
`96`		`- }`
`97`		`- }`
`98`		`- else {`
	`94`	`+ else`
`99`	`95`	`floatpart = floor(floatpart);`
	`96`	`+ if (floatpart >= denominator) {`
	`97`	`+ floatpart -= denominator;`
	`98`	`+ intpart += 1.0;`
`100`	`99`	`}`
	`100`	`+ assert(0.0 <= floatpart && floatpart < denominator);`
`101`	`101`
`102`	`102`	`*sec = (time_t)intpart;`
	`103`	`+ *numerator = (long)floatpart;`
	`104`	`+`
`103`	`105`	`err = intpart - (double)*sec;`
`104`	`106`	`if (err <= -1.0 \|\| err >= 1.0) {`
`105`	`107`	`error_time_t_overflow();`
`106`	`108`	`return -1;`
`107`	`109`	`}`
`108`		`-`
`109`		`- *numerator = (long)floatpart;`
`110`	`110`	`return 0;`
`111`	`111`	`}`
`112`	`112`
`@@ -123,9 +123,9 @@ _PyTime_ObjectToDenominator(PyObject obj, time_t sec, long *numerator,`
`123`	`123`	`}`
`124`	`124`	`else {`
`125`	`125`	`*sec = _PyLong_AsTime_t(obj);`
	`126`	`+ *numerator = 0;`
`126`	`127`	`if (*sec == (time_t)-1 && PyErr_Occurred())`
`127`	`128`	`return -1;`
`128`		`- *numerator = 0;`
`129`	`129`	`return 0;`
`130`	`130`	`}`
`131`	`131`	`}`
`@@ -167,7 +167,7 @@ _PyTime_ObjectToTimespec(PyObject obj, time_t sec, long *nsec,`
`167`	`167`	`{`
`168`	`168`	`int res;`
`169`	`169`	`res = _PyTime_ObjectToDenominator(obj, sec, nsec, 1e9, round);`
`170`		`- assert(0 <= nsec && nsec < SEC_TO_NS );`
	`170`	`+ assert(0 <= nsec && nsec < SEC_TO_NS);`
`171`	`171`	`return res;`
`172`	`172`	`}`
`173`	`173`
`@@ -177,7 +177,7 @@ _PyTime_ObjectToTimeval(PyObject obj, time_t sec, long *usec,`
`177`	`177`	`{`
`178`	`178`	`int res;`
`179`	`179`	`res = _PyTime_ObjectToDenominator(obj, sec, usec, 1e6, round);`
`180`		`- assert(0 <= usec && usec < SEC_TO_US );`
	`180`	`+ assert(0 <= usec && usec < SEC_TO_US);`
`181`	`181`	`return res;`
`182`	`182`	`}`
`183`	`183`
`@@ -444,12 +444,11 @@ _PyTime_AsTimeval_impl(_PyTime_t t, struct timeval *tv, _PyTime_round_t round,`
`444`	`444`	`tv->tv_sec += 1;`
`445`	`445`	`}`
`446`	`446`
	`447`	`+ assert(0 <= usec && usec < SEC_TO_US);`
	`448`	`+ tv->tv_usec = usec;`
	`449`	`+`
`447`	`450`	`if (res && raise)`
`448`	`451`	`_PyTime_overflow();`
`449`		`-`
`450`		`- assert(0 <= usec && usec <= 999999);`
`451`		`-`
`452`		`- tv->tv_usec = usec;`
`453`	`452`	`return res;`
`454`	`453`	`}`
`455`	`454`
`@@ -484,7 +483,7 @@ _PyTime_AsTimespec(_PyTime_t t, struct timespec *ts)`
`484`	`483`	`}`
`485`	`484`	`ts->tv_nsec = nsec;`
`486`	`485`
`487`		`- assert(0 <= ts->tv_nsec && ts->tv_nsec <= 999999999);`
	`486`	`+ assert(0 <= ts->tv_nsec && ts->tv_nsec < SEC_TO_NS);`
`488`	`487`	`return 0;`
`489`	`488`	`}`
`490`	`489`	`#endif`