Legoktm has uploaded a new change for review.

  https://gerrit.wikimedia.org/r/311915

Change subject: Initial import from MediaWiki core
......................................................................

Initial import from MediaWiki core

Change-Id: I758a98603d51ca0f1d4d70625b04ce9c87fa6d6d
---
A .editorconfig
A .gitignore
M .gitreview
A .travis.yml
A COPYING
A Doxyfile
A README.md
A composer.json
A phpcs.xml
A phpunit.xml.dist
A src/WaitConditionLoop.php
A tests/WaitConditionLoopTest.php
12 files changed, 862 insertions(+), 1 deletion(-)


  git pull ssh://gerrit.wikimedia.org:29418/mediawiki/libs/WaitConditionLoop 
refs/changes/15/311915/1

diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..42aefb6
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,6 @@
+# http://editorconfig.org
+root = true
+
+[*]
+indent_style = tab
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..3a761dd
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+/coverage
+/doc
+vendor
+composer.lock
diff --git a/.gitreview b/.gitreview
index 8925f9d..cd32255 100644
--- a/.gitreview
+++ b/.gitreview
@@ -1,6 +1,6 @@
 [gerrit]
 host=gerrit.wikimedia.org
 port=29418
-project=mediawiki/libs/WaitConditionLoop.git
+project=WaitConditionLoop.git
 defaultbranch=master
 defaultrebase=0
diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..5ec3af6
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,10 @@
+sudo: false
+language: php
+php:
+  - "5.5"
+  - "5.6"
+  - "hhvm"
+install:
+  - composer install
+script:
+  - composer test
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..d159169
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
diff --git a/Doxyfile b/Doxyfile
new file mode 100644
index 0000000..63db608
--- /dev/null
+++ b/Doxyfile
@@ -0,0 +1,26 @@
+# Doxyfile for WaitConditionLoop
+#
+# See <http://www.stack.nl/~dimitri/doxygen/manual/config.html>
+# for help on how to use this file to configure Doxygen.
+
+PROJECT_NAME           = "WaitConditionLoop"
+PROJECT_BRIEF          = "Wait loop that reaches a condition or times out"
+OUTPUT_DIRECTORY       = doc
+JAVADOC_AUTOBRIEF      = YES
+QT_AUTOBRIEF           = YES
+WARN_NO_PARAMDOC       = YES
+INPUT                  = README.md src/
+FILE_PATTERNS          = *.php
+RECURSIVE              = YES
+USE_MDFILE_AS_MAINPAGE = README.md
+HTML_DYNAMIC_SECTIONS  = YES
+GENERATE_TREEVIEW      = YES
+TREEVIEW_WIDTH         = 250
+GENERATE_LATEX         = NO
+HAVE_DOT               = YES
+DOT_FONTNAME           = Helvetica
+DOT_FONTSIZE           = 10
+TEMPLATE_RELATIONS     = YES
+CALL_GRAPH             = NO
+CALLER_GRAPH           = NO
+DOT_MULTI_TARGETS      = YES
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..814c8af
--- /dev/null
+++ b/README.md
@@ -0,0 +1,27 @@
+[![Latest Stable 
Version]](https://packagist.org/packages/wikimedia/wait-condition-loop) 
[![License]](https://packagist.org/packages/wikimedia/wait-condition-loop)
+
+Wait Condition Loop for PHP
+===========================
+
+todo Aaron should write stuff here.
+
+Additional documentation about the library can be found on
+[MediaWiki.org](https://www.mediawiki.org/wiki/WaitConditionLoop).
+
+
+Usage
+-----
+
+    // TODO Aaron write stuff here
+
+
+Running tests
+-------------
+
+    composer install --prefer-dist
+    composer test
+
+
+---
+[Latest Stable Version]: 
https://poser.pugx.org/wikimedia/wait-condition-loop/v/stable.svg
+[License]: https://poser.pugx.org/wikimedia/wait-condition-loop/license.svg
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..79b2cbb
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,30 @@
+{
+       "name": "wikimedia/wait-condition-loop",
+       "description": "Wait loop that reaches a condition or times out",
+       "license": "GPL-2.0+",
+       "homepage": "https://www.mediawiki.org/wiki/WaitConditionLoop";,
+       "authors": [
+               {
+                       "name": "Aaron Schulz",
+                       "email": "asch...@wikimedia.org"
+               }
+       ],
+       "autoload": {
+               "classmap": ["src/"]
+       },
+       "require": {
+               "php": ">=5.5.9"
+       },
+       "require-dev": {
+               "jakub-onderka/php-parallel-lint": "0.9.2",
+               "phpunit/phpunit": "4.8.24",
+               "mediawiki/mediawiki-codesniffer": "0.7.2"
+       },
+       "scripts": {
+               "test": [
+                       "parallel-lint . --exclude vendor",
+                       "phpunit",
+                       "phpcs -p -s"
+               ]
+       }
+}
diff --git a/phpcs.xml b/phpcs.xml
new file mode 100644
index 0000000..91e2148
--- /dev/null
+++ b/phpcs.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0"?>
+<ruleset name="WaitConditionLoop">
+       <rule ref="vendor/mediawiki/mediawiki-codesniffer/MediaWiki"/>
+
+       <file>.</file>
+       <exclude-pattern>coverage</exclude-pattern>
+       <exclude-pattern>vendor</exclude-pattern>
+       <exclude-pattern>doc/html</exclude-pattern>
+</ruleset>
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
new file mode 100644
index 0000000..973d48d
--- /dev/null
+++ b/phpunit.xml.dist
@@ -0,0 +1,14 @@
+<phpunit colors="true"
+       beStrictAboutTestsThatDoNotTestAnything="true"
+       beStrictAboutOutputDuringTests="true">
+       <testsuites>
+               <testsuite name="WaitConditionLoop Tests">
+                       <directory>./tests</directory>
+               </testsuite>
+       </testsuites>
+       <filter>
+               <whitelist addUncoveredFilesFromWhitelist="true">
+                       <directory suffix=".php">./src</directory>
+               </whitelist>
+       </filter>
+</phpunit>
diff --git a/src/WaitConditionLoop.php b/src/WaitConditionLoop.php
new file mode 100644
index 0000000..0e43b34
--- /dev/null
+++ b/src/WaitConditionLoop.php
@@ -0,0 +1,189 @@
+<?php
+/**
+ * Wait loop that reaches a condition or times out.
+ *
+ * Copyright (C) 2016 Aaron Schulz <asch...@wikimedia.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @author Aaron Schulz
+ */
+
+namespace Wikimedia;
+
+/**
+ * Wait loop that reaches a condition or times out
+ */
+class WaitConditionLoop {
+       /** @var callable */
+       private $condition;
+       /** @var callable[] */
+       private $busyCallbacks = [];
+       /** @var float Seconds */
+       private $timeout;
+       /** @var float Seconds */
+       private $lastWaitTime;
+       /** @var integer|null */
+       private $rusageMode;
+
+       const CONDITION_REACHED = 1;
+       const CONDITION_CONTINUE = 0; // evaluates as falsey
+       const CONDITION_FAILED = -1;
+       const CONDITION_TIMED_OUT = -2;
+       const CONDITION_ABORTED = -3;
+
+       /**
+        * @param callable $condition Callback that returns a 
WaitConditionLoop::CONDITION_ constant
+        * @param float $timeout Timeout in seconds
+        * @param array &$busyCallbacks List of callbacks to do useful work (by 
reference)
+        */
+       public function __construct( callable $condition, $timeout = 5.0, 
&$busyCallbacks = [] ) {
+               $this->condition = $condition;
+               $this->timeout = $timeout;
+               $this->busyCallbacks =& $busyCallbacks;
+
+               if ( defined( 'HHVM_VERSION' ) && PHP_OS === 'Linux' ) {
+                       $this->rusageMode = 2; // RUSAGE_THREAD
+               } elseif ( function_exists( 'getrusage' ) ) {
+                       $this->rusageMode = 0; // RUSAGE_SELF
+               }
+       }
+
+       /**
+        * Invoke the loop and continue until either:
+        *   - a) The condition callback returns neither CONDITION_CONTINUE nor 
false
+        *   - b) The timeout is reached
+        * This a condition callback can return true (stop) or false (continue) 
for convenience.
+        * In such cases, the halting result of "true" will be converted to 
CONDITION_REACHED.
+        *
+        * If $timeout is 0, then only the condition callback will be called 
(no busy callbacks),
+        * and this will immediately return CONDITION_FAILED if the condition 
was not met.
+        *
+        * Exceptions in callbacks will be caught and the callback will be 
swapped with
+        * one that simply rethrows that exception back to the caller when 
invoked.
+        *
+        * @return integer WaitConditionLoop::CONDITION_* constant
+        * @throws \Exception Any error from the condition callback
+        */
+       public function invoke() {
+               $elapsed = 0.0; // seconds
+               $sleepUs = 0; // microseconds to sleep each time
+               $lastCheck = false;
+               $finalResult = self::CONDITION_TIMED_OUT;
+               do {
+                       $checkStartTime = $this->getWallTime();
+                       // Check if the condition is met yet
+                       $realStart = $this->getWallTime();
+                       $cpuStart = $this->getCpuTime();
+                       $checkResult = call_user_func( $this->condition );
+                       $cpu = $this->getCpuTime() - $cpuStart;
+                       $real = $this->getWallTime() - $realStart;
+                       // Exit if the condition is reached, and error occurs, 
or this is non-blocking
+                       if ( $this->timeout <= 0 ) {
+                               $finalResult = $checkResult ? 
self::CONDITION_REACHED : self::CONDITION_FAILED;
+                               break;
+                       } elseif ( (int)$checkResult !== 
self::CONDITION_CONTINUE ) {
+                               if ( is_int( $checkResult ) ) {
+                                       $finalResult = $checkResult;
+                               } else {
+                                       $finalResult = self::CONDITION_REACHED;
+                               }
+                               break;
+                       } elseif ( $lastCheck ) {
+                               break; // timeout reached
+                       }
+                       // Detect if condition callback seems to block or if 
justs burns CPU
+                       $conditionUsesInterrupts = ( $real > 0.100 && $cpu <= 
$real * .03 );
+                       if ( !$this->popAndRunBusyCallback() && 
!$conditionUsesInterrupts ) {
+                               // 10 queries = 10(10+100)/2 ms = 550ms, 14 
queries = 1050ms
+                               $sleepUs = min( $sleepUs + 10 * 1e3, 1e6 ); // 
stop incrementing at ~1s
+                               $this->usleep( $sleepUs );
+                       }
+                       $checkEndTime = $this->getWallTime();
+                       // The max() protects against the clock getting set back
+                       $elapsed += max( $checkEndTime - $checkStartTime, 0.010 
);
+                       // Do not let slow callbacks timeout without checking 
the condition one more time
+                       $lastCheck = ( $elapsed >= $this->timeout );
+               } while ( true );
+
+               $this->lastWaitTime = $elapsed;
+
+               return $finalResult;
+       }
+
+       /**
+        * @return float Seconds
+        */
+       public function getLastWaitTime() {
+               return $this->lastWaitTime;
+       }
+
+       /**
+        * @param integer $microseconds
+        */
+       protected function usleep( $microseconds ) {
+               usleep( $microseconds );
+       }
+
+       /**
+        * @return float
+        */
+       protected function getWallTime() {
+               return microtime( true );
+       }
+
+       /**
+        * @return float Returns 0.0 if not supported (Windows on PHP < 7)
+        */
+       protected function getCpuTime() {
+               if ( $this->rusageMode === null ) {
+                       return microtime( true ); // assume worst case (all 
time is CPU)
+               }
+
+               $ru = getrusage( $this->rusageMode );
+               $time = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
+               $time += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
+
+               return $time;
+       }
+
+       /**
+        * Run one of the callbacks that does work ahead of time for another 
caller
+        *
+        * @return bool Whether a callback was executed
+        */
+       private function popAndRunBusyCallback() {
+               if ( $this->busyCallbacks ) {
+                       reset( $this->busyCallbacks );
+                       $key = key( $this->busyCallbacks );
+                       /** @var callable $workCallback */
+                       $workCallback =& $this->busyCallbacks[$key];
+                       try {
+                               $workCallback();
+                       } catch ( \Exception $e ) {
+                               $workCallback = function () use ( $e ) {
+                                       throw $e;
+                               };
+                       }
+                       unset( $this->busyCallbacks[$key] ); // consume
+
+                       return true;
+               }
+
+               return false;
+       }
+}
diff --git a/tests/WaitConditionLoopTest.php b/tests/WaitConditionLoopTest.php
new file mode 100644
index 0000000..51110c2
--- /dev/null
+++ b/tests/WaitConditionLoopTest.php
@@ -0,0 +1,207 @@
+<?php
+/**
+ * Copyright (C) 2016 Aaron Schulz <asch...@wikimedia.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @author Aaron Schulz <asch...@wikimedia.org>
+ */
+
+namespace Wikimedia\WaitConditionLoop\Test;
+
+use Wikimedia\WaitConditionLoop;
+
+class WaitConditionLoopFakeTime extends WaitConditionLoop {
+       protected $wallClock = 1;
+
+       function __construct( callable $condition, $timeout, array 
$busyCallbacks ) {
+               parent::__construct( $condition, $timeout, $busyCallbacks );
+       }
+
+       function usleep( $microseconds ) {
+               $this->wallClock += $microseconds / 1e6;
+       }
+
+       function getCpuTime() {
+               return 0.0;
+       }
+
+       function getWallTime() {
+               return $this->wallClock;
+       }
+
+       public function setWallClock( &$timestamp ) {
+               $this->wallClock =& $timestamp;
+       }
+}
+
+/**
+ * @covers WaitConditionLoop
+ */
+class WaitConditionLoopTest extends \PHPUnit_Framework_TestCase {
+       public function testCallbackReached() {
+               $wallClock = microtime( true );
+
+               $count = 0;
+               $status = new \stdClass();
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, $status ) {
+                               ++$count;
+                               $status->value = 'cookie';
+
+                               return WaitConditionLoop::CONDITION_REACHED;
+                       },
+                       10.0,
+                       $this->newBusyWork( $x, $y, $z )
+               );
+               $this->assertEquals( $loop::CONDITION_REACHED, $loop->invoke() 
);
+               $this->assertEquals( 1, $count );
+               $this->assertEquals( 'cookie', $status->value );
+               $this->assertEquals( [ 0, 0, 0 ], [ $x, $y, $z ], "No busy work 
done" );
+
+               $count = 0;
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, &$wallClock ) {
+                               $wallClock += 1;
+                               ++$count;
+
+                               return $count >= 2 ? 
WaitConditionLoop::CONDITION_REACHED : false;
+                       },
+                       7.0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock )
+               );
+               $this->assertEquals( $loop::CONDITION_REACHED, $loop->invoke(),
+                       "Busy work did not cause timeout" );
+               $this->assertEquals( [ 1, 0, 0 ], [ $x, $y, $z ] );
+
+               $count = 0;
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, &$wallClock ) {
+                               $wallClock += .1;
+                               ++$count;
+
+                               return $count > 80 ? true : false;
+                       },
+                       50.0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock, 
$dontCallMe, $badCalls )
+               );
+               $this->assertEquals( 0, $badCalls, "Callback exception not yet 
called" );
+               $this->assertEquals( $loop::CONDITION_REACHED, $loop->invoke() 
);
+               $this->assertEquals( [ 1, 1, 1 ], [ $x, $y, $z ], "Busy work 
done" );
+               $this->assertEquals( 1, $badCalls, "Bad callback ran and was 
exception caught" );
+
+               try {
+                       $e = null;
+                       $dontCallMe();
+               } catch ( \Exception $e ) {
+               }
+
+               $this->assertInstanceOf( 'RunTimeException', $e );
+               $this->assertEquals( 1, $badCalls, "Callback exception cached" 
);
+       }
+
+       public function testCallbackTimeout() {
+               $count = 0;
+               $wallClock = microtime( true );
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, &$wallClock ) {
+                               $wallClock += 3;
+                               ++$count;
+
+                               return $count > 300 ? true : false;
+                       },
+                       50.0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock )
+               );
+               $loop->setWallClock( $wallClock );
+               $this->assertEquals( $loop::CONDITION_TIMED_OUT, 
$loop->invoke() );
+               $this->assertEquals( [ 1, 1, 1 ], [ $x, $y, $z ], "Busy work 
done" );
+
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, &$wallClock ) {
+                               $wallClock += 3;
+                               ++$count;
+
+                               return true;
+                       },
+                       0.0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock )
+               );
+               $this->assertEquals( $loop::CONDITION_REACHED, $loop->invoke() 
);
+
+               $count = 0;
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$count, &$wallClock ) {
+                               $wallClock += 3;
+                               ++$count;
+
+                               return $count > 10 ? true : false;
+                       },
+                       0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock )
+               );
+               $this->assertEquals( $loop::CONDITION_FAILED, $loop->invoke() );
+       }
+
+       public function testCallbackAborted() {
+               $x = 0;
+               $wallClock = microtime( true );
+               $loop = new WaitConditionLoopFakeTime(
+                       function () use ( &$x, &$wallClock ) {
+                               $wallClock += 2;
+                               ++$x;
+
+                               return $x > 2 ? 
WaitConditionLoop::CONDITION_ABORTED : false;
+                       },
+                       10.0,
+                       $this->newBusyWork( $x, $y, $z, $wallClock )
+               );
+               $loop->setWallClock( $wallClock );
+               $this->assertEquals( $loop::CONDITION_ABORTED, $loop->invoke() 
);
+       }
+
+       private function newBusyWork(
+               &$x, &$y, &$z, &$wallClock = 1, &$dontCallMe = null, &$badCalls 
= 0
+       ) {
+               $x = $y = $z = 0;
+               $badCalls = 0;
+
+               $list = [];
+               $list[] = function () use ( &$x, &$wallClock ) {
+                       $wallClock += 1;
+
+                       return ++$x;
+               };
+               $dontCallMe = function () use ( &$badCalls ) {
+                       ++$badCalls;
+                       throw new \RuntimeException( "TrollyMcTrollFace" );
+               };
+               $list[] =& $dontCallMe;
+               $list[] = function () use ( &$y, &$wallClock ) {
+                       $wallClock += 15;
+
+                       return ++$y;
+               };
+               $list[] = function () use ( &$z, &$wallClock ) {
+                       $wallClock += 0.1;
+
+                       return ++$z;
+               };
+
+               return $list;
+       }
+}

-- 
To view, visit https://gerrit.wikimedia.org/r/311915
To unsubscribe, visit https://gerrit.wikimedia.org/r/settings

Gerrit-MessageType: newchange
Gerrit-Change-Id: I758a98603d51ca0f1d4d70625b04ce9c87fa6d6d
Gerrit-PatchSet: 1
Gerrit-Project: mediawiki/libs/WaitConditionLoop
Gerrit-Branch: master
Gerrit-Owner: Legoktm <legoktm.wikipe...@gmail.com>

_______________________________________________
MediaWiki-commits mailing list
MediaWiki-commits@lists.wikimedia.org
https://lists.wikimedia.org/mailman/listinfo/mediawiki-commits

Reply via email to