hphp/runtime/ext/asio/reschedule_wait_handle.cpp

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2013 Facebook, Inc. (http://www.facebook.com)     |
   6    | Copyright (c) 1997-2010 The PHP Group                                |
   7    +----------------------------------------------------------------------+
   8    | This source file is subject to version 3.01 of the PHP license,      |
   9    | that is bundled with this package in the file LICENSE, and is        |
  10    | available through the world-wide-web at the following url:           |
  11    | http://www.php.net/license/3_01.txt                                  |
  12    | If you did not receive a copy of the PHP license and are unable to   |
  13    | obtain it through the world-wide-web, please send a note to          |
  14    | license@php.net so we can mail you a copy immediately.               |
  15    +----------------------------------------------------------------------+
  16 */
  17
  18 #include "hphp/runtime/ext/ext_asio.h"
  19 #include "hphp/runtime/ext/asio/asio_context.h"
  20 #include "hphp/runtime/ext/asio/asio_session.h"
  21 #include "hphp/system/systemlib.h"
  22
  23 namespace HPHP {
  24 ///////////////////////////////////////////////////////////////////////////////
  25
  26 namespace {
  27   StaticString s_reschedule("<reschedule>");
  28 }
  29
  30 const int q_RescheduleWaitHandle$$QUEUE_DEFAULT = AsioContext::QUEUE_DEFAULT;
  31 const int q_RescheduleWaitHandle$$QUEUE_NO_PENDING_IO = AsioContext::QUEUE_NO_PENDING_IO;
  32
  33 c_RescheduleWaitHandle::c_RescheduleWaitHandle(Class *cb)
  34     : c_WaitableWaitHandle(cb) {
  35 }
  36
  37 c_RescheduleWaitHandle::~c_RescheduleWaitHandle() {
  38 }
  39
  40 void c_RescheduleWaitHandle::t___construct() {
  41   Object e(SystemLib::AllocInvalidOperationExceptionObject(
  42         "Use RescheduleWaitHandle::create() instead of constructor"));
  43   throw e;
  44 }
  45
  46 Object c_RescheduleWaitHandle::ti_create(int queue, int priority) {
  47   if (UNLIKELY(
  48       queue != q_RescheduleWaitHandle$$QUEUE_DEFAULT &&
  49       queue != q_RescheduleWaitHandle$$QUEUE_NO_PENDING_IO)) {
  50     Object e(SystemLib::AllocInvalidArgumentExceptionObject(
  51         "Expected queue to be a value defined by one of the QUEUE_ constants"));
  52     throw e;
  53   }
  54
  55   if (UNLIKELY(priority < 0)) {
  56     Object e(SystemLib::AllocInvalidArgumentExceptionObject(
  57         "Expected priority to be a non-negative integer"));
  58     throw e;
  59   }
  60
  61   c_RescheduleWaitHandle* wh = NEWOBJ(c_RescheduleWaitHandle);
  62   wh->initialize(static_cast<uint32_t>(queue), static_cast<uint32_t>(priority));
  63   return wh;
  64 }
  65
  66 void c_RescheduleWaitHandle::initialize(uint32_t queue, uint32_t priority) {
  67   m_queue = queue;
  68   m_priority = priority;
  69
  70   setState(STATE_SCHEDULED);
  71   if (isInContext()) {
  72     getContext()->schedule(this, m_queue, m_priority);
  73   }
  74 }
  75
  76 void c_RescheduleWaitHandle::run() {
  77   // may happen if scheduled in multiple contexts
  78   if (getState() != STATE_SCHEDULED) {
  79     return;
  80   }
  81
  82   setResult(init_null_variant.asTypedValue());
  83 }
  84
  85 String c_RescheduleWaitHandle::getName() {
  86   return s_reschedule;
  87 }
  88
  89 void c_RescheduleWaitHandle::enterContext(context_idx_t ctx_idx) {
  90   assert(AsioSession::Get()->getContext(ctx_idx));
  91
  92   // stop before corrupting unioned data
  93   if (isFinished()) {
  94     return;
  95   }
  96
  97   // already in the more specific context?
  98   if (LIKELY(getContextIdx() >= ctx_idx)) {
  99     return;
 100   }
 101
 102   assert(getState() == STATE_SCHEDULED);
 103
 104   setContextIdx(ctx_idx);
 105   getContext()->schedule(this, m_queue, m_priority);
 106 }
 107
 108 void c_RescheduleWaitHandle::exitContext(context_idx_t ctx_idx) {
 109   assert(AsioSession::Get()->getContext(ctx_idx));
 110
 111   // stop before corrupting unioned data
 112   if (isFinished()) {
 113     return;
 114   }
 115
 116   // not in a context being exited
 117   assert(getContextIdx() <= ctx_idx);
 118   if (getContextIdx() != ctx_idx) {
 119     return;
 120   }
 121
 122   if (UNLIKELY(getState() != STATE_SCHEDULED)) {
 123     throw FatalErrorException(
 124       "Invariant violation: encountered unexpected state");
 125   }
 126
 127   // move us to the parent context
 128   setContextIdx(getContextIdx() - 1);
 129
 130   // reschedule if still in a context
 131   if (isInContext()) {
 132     getContext()->schedule(this, m_queue, m_priority);
 133   }
 134
 135   // recursively move all wait handles blocked by us
 136   for (auto pwh = getFirstParent(); pwh; pwh = pwh->getNextParent()) {
 137     pwh->exitContextBlocked(ctx_idx);
 138   }
 139 }
 140
 141 ///////////////////////////////////////////////////////////////////////////////
 142 }