wine/gecko
0
0
Fork 0
mirror of https://gitlab.winehq.org/wine/wine-gecko.git synced 2024-09-13 09:24:08 -07:00
Code Issues Packages Projects Releases Wiki Activity

Bug 1137898 - Migrate to android:versionCode scheme v1. r=rnewman,snorp

Browse Source 
Android version codes serve multiple masters.  They indicate newer
versions, yes; but they also break ties between versions with
different features and requirements. High order bits effectively
partition the space of versions and are valuable.  Since Android
version codes are signed Java integers, we have 31 bits to work with.
Mozilla's traditional build ID is YYYYMMDDhhmmss.  This was chopped to
ten characters (YYYYMMDDhh, i.e., hourly build IDs) and then converted
to a decimal.  This took many high order bits.  We will lose another
high order bit in the 36th month of 2015 -- i.e., as soon as the year
rolls over to 2016.  If we waited to lose the next higher order bit,
we'd lose that one in the 46th month of 2017 -- i.e., as soon as the
year rolls over to 2018.

The following patch sacrifices a high order bit to change the version
scheme, winning us roughly 15 years of hourly build IDs before we are
forced to lose another high order bit.  So it's clearly to our
advantage to change the scheme sooner rather than later -- we will
sacrifice 1 bit for 15 years of build IDs, rather than keeping the
current scheme and sacrificing (say) 2 bits for 3 years of build IDs.

The resulting scheme produces build IDs that look like (in binary):

0111 1000 0010 tttt tttt tttt tttt txpg

The meaning of these build IDs is documented in the Python source code
that generates them.
This commit is contained in:
Nick Alexander 2015-08-26 18:34:48 -07:00
parent a067f87693
commit 595c486984
2 changed files with 151 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
python/mozbuild/mozbuild/android_version_code.py
View File

@ -5,10 +5,15 @@
from __future__ import absolute_import, print_function
import argparse
import math
import sys
import time
# Builds before this build ID use the v0 version scheme. Builds after this
# build ID use the v1 version scheme.
V1_CUTOFF = 20150801000000 # YYYYmmddHHMMSS
def android_version_code(buildid, cpu_arch=None, min_sdk=0, max_sdk=0):
def android_version_code_v0(buildid, cpu_arch=None, min_sdk=0, max_sdk=0):
base = int(str(buildid)[:10])
# None is interpreted as arm.
if not cpu_arch or cpu_arch in ['armeabi', 'armeabi-v7a']:
@ -23,7 +28,104 @@ def android_version_code(buildid, cpu_arch=None, min_sdk=0, max_sdk=0):
return base + min_sdk + 3
else:
raise ValueError("Don't know how to compute android:versionCode "
"for CPU arch " + cpu_arch)
"for CPU arch %s" % cpu_arch)
def android_version_code_v1(buildid, cpu_arch=None, min_sdk=0, max_sdk=0):
'''Generate a v1 android:versionCode.
The important consideration is that version codes be monotonically
increasing (per Android package name) for all published builds. The input
build IDs are based on timestamps and hence are always monotonically
increasing.
The generated v1 version codes look like (in binary):
0111 1000 0010 tttt tttt tttt tttt txpg
The 17 bits labelled 't' represent the number of hours since midnight on
September 1, 2015. (2015090100 in YYYYMMMDDHH format.) This yields a
little under 15 years worth of hourly build identifiers, since 2**17 / (366
* 24) =~ 14.92.
The bits labelled 'x', 'p', and 'g' are feature flags.
The bit labelled 'x' is 1 if the build is for an x86 architecture and 0
otherwise, which means the build is for an ARM architecture. (Fennec no
longer supports ARMv6, so ARM is equivalent to ARMv7 and above.)
The bit labelled 'p' is a placeholder that is always 0 (for now).
The bit labelled 'g' is 1 if the build is targetting Android API 11+ and 0
otherwise, which means the build targets Android API 9-10 (Gingerbread).
(Fennec no longer supports below Android API 9.)
We throw an explanatory exception when we are within one calendar year of
running out of build events. This gives lots of time to update the version
scheme. The responsible individual should then bump the range (to allow
builds to continue) and use the time remaining to update the version scheme
via the reserved high order bits.
N.B.: the reserved 0 bit to the left of the highest order 't' bit can,
sometimes, be used to bump the version scheme. In addition, by reducing the
granularity of the build identifiers (for example, moving to identifying
builds every 2 or 4 hours), the version scheme may be adjusted further still
without losing a (valuable) high order bit.
'''
def hours_since_cutoff(buildid):
# The ID is formatted like YYYYMMDDHHMMSS (using
# datetime.now().strftime('%Y%m%d%H%M%S'); see
# toolkit/xre/make-platformini.py). The inverse function is
# time.strptime. N.B.: the time module expresses time as decimal
# seconds since the epoch.
fmt = '%Y%m%d%H%M%S'
build = time.strptime(str(buildid), fmt)
cutoff = time.strptime(str(V1_CUTOFF), fmt)
return int(math.floor((time.mktime(build) - time.mktime(cutoff)) / (60.0 * 60.0)))
# Of the 21 low order bits, we take 17 bits for builds.
base = hours_since_cutoff(buildid)
if base < 0:
raise ValueError("Something has gone horribly wrong: cannot calculate "
"android:versionCode from build ID %s: hours underflow "
"bits allotted!" % buildid)
if base > 2**17:
raise ValueError("Something has gone horribly wrong: cannot calculate "
"android:versionCode from build ID %s: hours overflow "
"bits allotted!" % buildid)
if base > 2**17 - 366 * 24:
raise ValueError("Running out of low order bits calculating "
"android:versionCode from build ID %s: "
"; YOU HAVE ONE YEAR TO UPDATE THE VERSION SCHEME." % buildid)
version = 0b1111000001000000000000000000000
# We reserve 1 "middle" high order bit for the future, and 3 low order bits
# for architecture and APK splits.
version |= base << 3
# None is interpreted as arm.
if not cpu_arch or cpu_arch in ['armeabi', 'armeabi-v7a']:
# 0 is interpreted as SDK 9.
if not min_sdk or min_sdk == 9:
pass
elif min_sdk == 11:
version |= 1 << 0
else:
raise ValueError("Don't know how to compute android:versionCode "
"for CPU arch %s and min SDK %s" % (cpu_arch, min_sdk))
elif cpu_arch in ['x86']:
version |= 1 << 2
else:
raise ValueError("Don't know how to compute android:versionCode "
"for CPU arch %s" % cpu_arch)
return version
def android_version_code(buildid, *args, **kwargs):
base = int(str(buildid))
if base < V1_CUTOFF:
return android_version_code_v0(buildid, *args, **kwargs)
else:
return android_version_code_v1(buildid, *args, **kwargs)
def main(argv):

52
python/mozbuild/mozbuild/test/test_android_version_code.py
View File

@ -5,18 +5,60 @@
from mozunit import main
import unittest
from mozbuild.android_version_code import android_version_code
from mozbuild.android_version_code import (
android_version_code_v0,
android_version_code_v1,
)
class TestAndroidVersionCode(unittest.TestCase):
def test_basic(self):
def test_android_version_code_v0(self):
# From https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&revision=e25de9972a77.
buildid = '20150708104620'
arm_api9 = 2015070819
arm_api11 = 2015070821
x86_api9 = 2015070822
self.assertEqual(android_version_code(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None), arm_api9)
self.assertEqual(android_version_code(buildid, cpu_arch='armeabi-v7a', min_sdk=11, max_sdk=None), arm_api11)
self.assertEqual(android_version_code(buildid, cpu_arch='x86', min_sdk=9, max_sdk=None), x86_api9)
self.assertEqual(android_version_code_v0(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None), arm_api9)
self.assertEqual(android_version_code_v0(buildid, cpu_arch='armeabi-v7a', min_sdk=11, max_sdk=None), arm_api11)
self.assertEqual(android_version_code_v0(buildid, cpu_arch='x86', min_sdk=9, max_sdk=None), x86_api9)
def test_android_version_code_v1(self):
buildid = '20150825141628'
arm_api9 = 0b01111000001000000001001001110000
arm_api11 = 0b01111000001000000001001001110001
x86_api9 = 0b01111000001000000001001001110100
self.assertEqual(android_version_code_v1(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None), arm_api9)
self.assertEqual(android_version_code_v1(buildid, cpu_arch='armeabi-v7a', min_sdk=11, max_sdk=None), arm_api11)
self.assertEqual(android_version_code_v1(buildid, cpu_arch='x86', min_sdk=9, max_sdk=None), x86_api9)
def test_android_version_code_v1_underflow(self):
'''Verify that it is an error to ask for v1 codes predating the cutoff.'''
buildid = '201508010000' # Earliest possible.
arm_api9 = 0b01111000001000000000000000000000
self.assertEqual(android_version_code_v1(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None), arm_api9)
with self.assertRaises(ValueError) as cm:
underflow = '201507310000' # Latest possible (valid) underflowing date.
android_version_code_v1(underflow, cpu_arch='armeabi', min_sdk=9, max_sdk=None)
self.assertTrue('underflow' in cm.exception.message)
def test_android_version_code_v1_running_low(self):
'''Verify there is an informative message if one asks for v1 codes that are close to overflow.'''
with self.assertRaises(ValueError) as cm:
overflow = '20290801000000'
android_version_code_v1(overflow, cpu_arch='armeabi', min_sdk=9, max_sdk=None)
self.assertTrue('Running out of low order bits' in cm.exception.message)
def test_android_version_code_v1_overflow(self):
'''Verify that it is an error to ask for v1 codes that actually does overflow.'''
with self.assertRaises(ValueError) as cm:
overflow = '20310801000000'
android_version_code_v1(overflow, cpu_arch='armeabi', min_sdk=9, max_sdk=None)
self.assertTrue('overflow' in cm.exception.message)
def test_android_version_code_v0_relative_v1(self):
'''Verify that the first v1 code is greater than the equivalent v0 code.'''
buildid = '20150801000000'
self.assertGreater(android_version_code_v1(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None),
android_version_code_v0(buildid, cpu_arch='armeabi', min_sdk=9, max_sdk=None))
if __name__ == '__main__':