PHP 7: Fix negative bitshift error when no buckets are enabled #38
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If a slug exists in the database but no buckets are enabled, we get back an empty string. The empty string gets coreced into 0, then we subtact 1 to do the bitshift, and we end up with the negative bitshift error. In php 5.x this is a silent error where the value ends up being int(-9223372036854775808), but in php 7.1 it's a fatal error. With this change when we reduce the array, if $index is 0 we just return the $mask we have accumulated so far. There's no need to shift the 0 $index so we avoid it by returning early. Below are some examples of what reduceToBitmask was returning: Before: ``` When Test.a swivel_features = 1,2,3,4,5,6,7,8,9,10 reduceToBitmask() returned int(1023) When Test.a swivel_features = "" reduceToBitmask() returned int(-9223372036854775808) ``` Now: ``` When Test.a swivel_features = 1,2,3,4,5,6,7,8,9,10 reduceToBitmask() returns int(1023) When Test.a swivel_features = "" reduceToBitmask() returns int(0) ``` Signed-off-by: Rene Fragoso <ctrlrsf@gmail.com>
These tests confirm graceful handling of swivels with no buckets enabled. If not handled properly, they would result in a negative bitshift error. Signed-off-by: Rene Fragoso <ctrlrsf@gmail.com>
jrbasso
approved these changes
Sep 5, 2017
|
Tagged as v1.3.3. |
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If a slug exists in the database but no buckets are enabled, we get back
an empty string. The empty string gets coreced into 0, then we subtact
1 to do the bitshift, and we end up with the negative bitshift error. In
php 5.x this is a silent error where the value ends up being
int(-9223372036854775808), but in php 7.1 it's a fatal error.
With this change when we reduce the array, if $index is 0 we just return
the $mask we have accumulated so far. There's no need to shift the 0
$index so we avoid it by returning early.
Closes: #33
Below are some examples of what reduceToBitmask was returning:
Before:
Now: