Index: third_party/google-endpoints/Crypto/Util/_number_new.py |
diff --git a/third_party/google-endpoints/Crypto/Util/_number_new.py b/third_party/google-endpoints/Crypto/Util/_number_new.py |
new file mode 100644 |
index 0000000000000000000000000000000000000000..b040025f38801d877aa767c49b84abeeedd2fa1c |
--- /dev/null |
+++ b/third_party/google-endpoints/Crypto/Util/_number_new.py |
@@ -0,0 +1,119 @@ |
+# -*- coding: ascii -*- |
+# |
+# Util/_number_new.py : utility functions |
+# |
+# Written in 2008 by Dwayne C. Litzenberger <dlitz@dlitz.net> |
+# |
+# =================================================================== |
+# The contents of this file are dedicated to the public domain. To |
+# the extent that dedication to the public domain is not available, |
+# everyone is granted a worldwide, perpetual, royalty-free, |
+# non-exclusive license to exercise all rights associated with the |
+# contents of this file for any purpose whatsoever. |
+# No rights are reserved. |
+# |
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS |
+# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
+# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
+# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
+# SOFTWARE. |
+# =================================================================== |
+ |
+## NOTE: Do not import this module directly. Import these functions from Crypto.Util.number. |
+ |
+__revision__ = "$Id$" |
+__all__ = ['ceil_shift', 'ceil_div', 'floor_div', 'exact_log2', 'exact_div'] |
+ |
+import sys |
+if sys.version_info[0] == 2 and sys.version_info[1] == 1: |
+ from Crypto.Util.py21compat import * |
+ |
+def ceil_shift(n, b): |
+ """Return ceil(n / 2**b) without performing any floating-point or division operations. |
+ |
+ This is done by right-shifting n by b bits and incrementing the result by 1 |
+ if any '1' bits were shifted out. |
+ """ |
+ if not isinstance(n, (int, long)) or not isinstance(b, (int, long)): |
+ raise TypeError("unsupported operand type(s): %r and %r" % (type(n).__name__, type(b).__name__)) |
+ |
+ assert n >= 0 and b >= 0 # I haven't tested or even thought about negative values |
+ mask = (1L << b) - 1 |
+ if n & mask: |
+ return (n >> b) + 1 |
+ else: |
+ return n >> b |
+ |
+def ceil_div(a, b): |
+ """Return ceil(a / b) without performing any floating-point operations.""" |
+ |
+ if not isinstance(a, (int, long)) or not isinstance(b, (int, long)): |
+ raise TypeError("unsupported operand type(s): %r and %r" % (type(a).__name__, type(b).__name__)) |
+ |
+ (q, r) = divmod(a, b) |
+ if r: |
+ return q + 1 |
+ else: |
+ return q |
+ |
+def floor_div(a, b): |
+ if not isinstance(a, (int, long)) or not isinstance(b, (int, long)): |
+ raise TypeError("unsupported operand type(s): %r and %r" % (type(a).__name__, type(b).__name__)) |
+ |
+ (q, r) = divmod(a, b) |
+ return q |
+ |
+def exact_log2(num): |
+ """Find and return an integer i >= 0 such that num == 2**i. |
+ |
+ If no such integer exists, this function raises ValueError. |
+ """ |
+ |
+ if not isinstance(num, (int, long)): |
+ raise TypeError("unsupported operand type: %r" % (type(num).__name__,)) |
+ |
+ n = long(num) |
+ if n <= 0: |
+ raise ValueError("cannot compute logarithm of non-positive number") |
+ |
+ i = 0 |
+ while n != 0: |
+ if (n & 1) and n != 1: |
+ raise ValueError("No solution could be found") |
+ i += 1 |
+ n >>= 1 |
+ i -= 1 |
+ |
+ assert num == (1L << i) |
+ return i |
+ |
+def exact_div(p, d, allow_divzero=False): |
+ """Find and return an integer n such that p == n * d |
+ |
+ If no such integer exists, this function raises ValueError. |
+ |
+ Both operands must be integers. |
+ |
+ If the second operand is zero, this function will raise ZeroDivisionError |
+ unless allow_divzero is true (default: False). |
+ """ |
+ |
+ if not isinstance(p, (int, long)) or not isinstance(d, (int, long)): |
+ raise TypeError("unsupported operand type(s): %r and %r" % (type(p).__name__, type(d).__name__)) |
+ |
+ if d == 0 and allow_divzero: |
+ n = 0 |
+ if p != n * d: |
+ raise ValueError("No solution could be found") |
+ else: |
+ (n, r) = divmod(p, d) |
+ if r != 0: |
+ raise ValueError("No solution could be found") |
+ |
+ assert p == n * d |
+ return n |
+ |
+# vim:set ts=4 sw=4 sts=4 expandtab: |