Add some more module maintainers.

Misc/maintainers.rst

@@ -69,7 +69,7 @@ cmd
 code
 codecs
 codeop
-collections
+collections         rhettinger
 colorsys
 compileall
 configparser
@@ -120,7 +120,7 @@ imp
 importlib           brett.cannon
 inspect
 io                  pitrou, benjamin.peterson
-itertools
+itertools           rhettinger
 json
 keyword
 lib2to3             benjamin.peterson
@@ -166,13 +166,13 @@ pyclbr
 pydoc
 queue
 quopri
-random
+random              rhettinger
 re
 readline
 reprlib
 resource
 rlcompleter
-runpy
+runpy               ncoghlan
 sched
 select
 shelve

Objects/longobject.c

@@ -1775,9 +1775,9 @@ _PyLong_Format(PyObject *aa, int base)
 	Py_ssize_t i, sz;
 	Py_ssize_t size_a;
 	Py_UNICODE *p;
-	int bits;
-	char sign = '\0';
+	int bits, negative;
 
+	assert(base == 2 || base == 8 || base == 10 || base == 16);
 	if (base == 10)
 		return long_to_decimal_string((PyObject *)a);
 
@@ -1785,23 +1785,34 @@ _PyLong_Format(PyObject *aa, int base)
 		PyErr_BadInternalCall();
 		return NULL;
 	}
-	assert(base >= 2 && base <= 36);
 	size_a = ABS(Py_SIZE(a));
+	negative = Py_SIZE(a) < 0;
 
 	/* Compute a rough upper bound for the length of the string */
-	i = base;
-	bits = 0;
-	while (i > 1) {
-		++bits;
-		i >>= 1;
+	switch (base) {
+	case 2:
+		bits = 1;
+		break;
+	case 8:
+		bits = 3;
+		break;
+	case 16:
+		bits = 4;
+		break;
+	default:
+		assert(0); /* never get here */
 	}
+
+	/* length of string required: +1 for negative sign, +2 for prefix */
 	i = 5;
 	/* ensure we don't get signed overflow in sz calculation */
-	if (size_a > (PY_SSIZE_T_MAX - i) / PyLong_SHIFT) {
+	if (size_a > (PY_SSIZE_T_MAX - 4) / PyLong_SHIFT) {
 		PyErr_SetString(PyExc_OverflowError,
 				"int is too large to format");
 		return NULL;
 	}
+	sz = 3 + negative + (size_a * PyLong_SHIFT - 1) / bits;
+
 	sz = i + 1 + (size_a * PyLong_SHIFT - 1) / bits;
 	assert(sz >= 0);
 	str = PyUnicode_FromUnicode(NULL, sz);
@@ -1809,112 +1820,41 @@ _PyLong_Format(PyObject *aa, int base)
 		return NULL;
 	p = PyUnicode_AS_UNICODE(str) + sz;
 	*p = '\0';
-	if (Py_SIZE(a) < 0)
-		sign = '-';
 
 	if (Py_SIZE(a) == 0) {
 		*--p = '0';
 	}
-	else if ((base & (base - 1)) == 0) {
-		/* JRH: special case for power-of-2 bases */
-		twodigits accum = 0;
-		int accumbits = 0;	/* # of bits in accum */
-		int basebits = 1;	/* # of bits in base-1 */
-		i = base;
-		while ((i >>= 1) > 1)
-			++basebits;
-
-		for (i = 0; i < size_a; ++i) {
-			accum |= (twodigits)a->ob_digit[i] << accumbits;
-			accumbits += PyLong_SHIFT;
-			assert(accumbits >= basebits);
-			do {
-				char cdigit = (char)(accum & (base - 1));
-				cdigit += (cdigit < 10) ? '0' : 'a'-10;
-				assert(p > PyUnicode_AS_UNICODE(str));
-				*--p = cdigit;
-				accumbits -= basebits;
-				accum >>= basebits;
-			} while (i < size_a-1 ? accumbits >= basebits :
-						accum > 0);
-		}
-	}
-	else {
-		/* Not 0, and base not a power of 2.  Divide repeatedly by
-		   base, but for speed use the highest power of base that
-		   fits in a digit. */
-		Py_ssize_t size = size_a;
-		digit *pin = a->ob_digit;
-		PyLongObject *scratch;
-		/* powbasw <- largest power of base that fits in a digit. */
-		digit powbase = base;  /* powbase == base ** power */
-		int power = 1;
-		for (;;) {
-			twodigits newpow = powbase * (twodigits)base;
-			if (newpow >> PyLong_SHIFT)
-				/* doesn't fit in a digit */
-				break;
-			powbase = (digit)newpow;
-			++power;
-		}
-
-		/* Get a scratch area for repeated division. */
-		scratch = _PyLong_New(size);
-		if (scratch == NULL) {
-			Py_DECREF(str);
-			return NULL;
-		}
+	assert((base & (base-1)) = 0);
+	/* JRH: special case for power-of-2 bases */
+	twodigits accum = 0;
+	int accumbits = 0;	/* # of bits in accum */
+	int basebits = 1;	/* # of bits in base-1 */
+	i = base;
+	while ((i >>= 1) > 1)
+		++basebits;
 
-		/* Repeatedly divide by powbase. */
+	for (i = 0; i < size_a; ++i) {
+		accum |= (twodigits)a->ob_digit[i] << accumbits;
+		accumbits += PyLong_SHIFT;
+		assert(accumbits >= basebits);
 		do {
-			int ntostore = power;
-			digit rem = inplace_divrem1(scratch->ob_digit,
-						     pin, size, powbase);
-			pin = scratch->ob_digit; /* no need to use a again */
-			if (pin[size - 1] == 0)
-				--size;
-			SIGCHECK({
-				Py_DECREF(scratch);
-				Py_DECREF(str);
-				return NULL;
-			})
-
-			/* Break rem into digits. */
-			assert(ntostore > 0);
-			do {
-				digit nextrem = (digit)(rem / base);
-				char c = (char)(rem - nextrem * base);
-				assert(p > PyUnicode_AS_UNICODE(str));
-				c += (c < 10) ? '0' : 'a'-10;
-				*--p = c;
-				rem = nextrem;
-				--ntostore;
-				/* Termination is a bit delicate:  must not
-				   store leading zeroes, so must get out if
-				   remaining quotient and rem are both 0. */
-			} while (ntostore && (size || rem));
-		} while (size != 0);
-		Py_DECREF(scratch);
+			char cdigit = (char)(accum & (base - 1));
+			cdigit += (cdigit < 10) ? '0' : 'a'-10;
+			assert(p > PyUnicode_AS_UNICODE(str));
+			*--p = cdigit;
+			accumbits -= basebits;
+			accum >>= basebits;
+		} while (i < size_a-1 ? accumbits >= basebits :
+			 accum > 0);
 	}
 
-	if (base == 16) {
+	if (base == 16)
 		*--p = 'x';
-		*--p = '0';
-	}
-	else if (base == 8) {
+	else if (base == 8)
 		*--p = 'o';
-		*--p = '0';
-	}
-	else if (base == 2) {
+	else /* base == 2 */
 		*--p = 'b';
-		*--p = '0';
-	}
-	else if (base != 10) {
-		*--p = '#';
-		*--p = '0' + base%10;
-		if (base > 10)
-			*--p = '0' + base/10;
-	}
+	*--p = '0';
 	if (sign)
 		*--p = sign;
 	if (p != PyUnicode_AS_UNICODE(str)) {