increment function working incorrectly (with binary protocol) about php-memcached HOT 6 CLOSED

With decrement it's the same:

from php-memcached.

We're experiencing the same issue here.

from php-memcached.

This is blocker for me - anyone have a workaround for this? If you do any operation before the increment/decrement it will always return -1:

php-memcached v2.1.0, libmemcached 1.0.15, ubuntu 12.04 64bit.

ex:

<?php
$m = new Memcached();
$newServers = array(
                  array('localhost', 11211, 100),
              );            
$m->setOption(Memcached::OPT_BINARY_PROTOCOL, true);

$m->addServers($newServers);

$d = $m->get('foo');

$m->set('counter', 5);
$n = $m->decrement('counter');  //should return 4, returns -1!?!?
var_dump($n);

$n = $m->decrement('counter', 10);
var_dump($n);

var_dump($m->get('counter'));

$m->set('counter', 'abc');
$n = $m->increment('counter');
var_dump($n);

Output is:

int(-1) int(4) int(0) int(-1)

from php-memcached.

I have a workaround. Using getMulti() instead of get() stops this issue from occurring. The code path for getMulti() and get() are very different. From bvis's example we can see the bug occur.

<?php

$m = new Memcached();
$m->addServer('localhost', '11211');
$m->setOption(Memcached::OPT_BINARY_PROTOCOL, true);

$key = uniqid('testIncrement');
assert($m->add($key, 7, 2) === true); // Adding value 7
assert($m->get($key) === 7); // Check right value was saved
assert($m->decrement($key, 2) === 5); // Decrement to 5

However this code works and does not have the bug:

<?php

$m = new Memcached();
$m->addServer('localhost', '11211');
$m->setOption(Memcached::OPT_BINARY_PROTOCOL, true);

$key = uniqid('testIncrement');
assert($m->add($key, 7, 2) === true); // Adding value 7
$retVal = $m->getMulti(array($key)); // Check right value was saved
assert($retVal[$key] === 7); // Check right value was saved
assert($m->decrement($key, 2) === 5); // Decrement to 5

The function php_memc_get_impl() in php_memcached.c uses the libmemcached function memcached_fetch(). The function memcached_fetch() is deprecated:

http://docs.libmemcached.org/libmemcached/memcached_fetch.html

I believe memcached_fetch() is causing this problem but I will have to do more research to confirm.

from php-memcached.

Thanks for the update. I have modified my app code to do what you mention and it seems to be working.

from php-memcached.

I haven't run the tests here explicitly but I believe pull request #75 should fix this.

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