| 1 |
<?php |
| 2 |
|
| 3 |
if (!defined('ABSPATH')) { |
| 4 |
exit; |
| 5 |
} |
| 6 |
|
| 7 |
/** |
| 8 |
* Capability-safe boundary for the pcntl signal functions. |
| 9 |
* |
| 10 |
* Split from ABJ_404_Solution_PhpRuntimeCapabilityAdapter along the line the |
| 11 |
* HOST splits on. Everything that adapter wraps can be removed one function at |
| 12 |
* a time through disable_functions, but pcntl is an extension: it is absent as |
| 13 |
* a unit on most shared hosting and on every non-CLI SAPI build that omits it, |
| 14 |
* so "can this host use signals at all" is one question with one answer rather |
| 15 |
* than four independent probes. |
| 16 |
* |
| 17 |
* These four are also not four capabilities. They are the steps of one |
| 18 |
* protocol -- check support, enable async dispatch, install the handler, arm |
| 19 |
* and disarm the alarm -- and exactly one caller runs it, |
| 20 |
* ABJ_404_Solution_PostResponseWorkerBudget, which is the post-response |
| 21 |
* wall-clock budget itself. Keeping the protocol in one place is what lets |
| 22 |
* supportsSignalBudget() be the single precondition the caller checks instead |
| 23 |
* of each step failing separately halfway through. |
| 24 |
* |
| 25 |
* Depends on the main adapter for the availability check and never the other |
| 26 |
* way round, so the boundary classes stay acyclic. |
| 27 |
*/ |
| 28 |
final class ABJ_404_Solution_PcntlSignalAdapter { |
| 29 |
|
| 30 |
/** Functions this boundary owns; consumed by the disable-functions lint. */ |
| 31 |
private const OWNED_FUNCTIONS = array( |
| 32 |
'pcntl_alarm', |
| 33 |
'pcntl_async_signals', |
| 34 |
'pcntl_signal', |
| 35 |
); |
| 36 |
|
| 37 |
/** @return array<int, string> Functions whose direct use this boundary owns. */ |
| 38 |
public static function ownedFunctions(): array { |
| 39 |
return self::OWNED_FUNCTIONS; |
| 40 |
} |
| 41 |
|
| 42 |
/** |
| 43 |
* Whether every function the post-response signal budget needs exists. |
| 44 |
* |
| 45 |
* All three, not any: arming an alarm whose handler could not be installed |
| 46 |
* would leave a SIGALRM with the default disposition, which terminates the |
| 47 |
* process rather than ending the budget. |
| 48 |
*/ |
| 49 |
public static function supportsSignalBudget(): bool { |
| 50 |
foreach (self::OWNED_FUNCTIONS as $function) { |
| 51 |
if (!ABJ_404_Solution_PhpRuntimeCapabilityAdapter::isFunctionAvailable($function)) { |
| 52 |
return false; |
| 53 |
} |
| 54 |
} |
| 55 |
return true; |
| 56 |
} |
| 57 |
|
| 58 |
/** Enable asynchronous signal dispatch when supported. */ |
| 59 |
public static function enableAsyncSignals(): bool { |
| 60 |
return ABJ_404_Solution_PhpRuntimeCapabilityAdapter::isFunctionAvailable('pcntl_async_signals') |
| 61 |
&& pcntl_async_signals(true); |
| 62 |
} |
| 63 |
|
| 64 |
/** Install one signal handler when supported. */ |
| 65 |
public static function installSignalHandler(int $signal, callable $handler): bool { |
| 66 |
return ABJ_404_Solution_PhpRuntimeCapabilityAdapter::isFunctionAvailable('pcntl_signal') |
| 67 |
&& pcntl_signal($signal, $handler); |
| 68 |
} |
| 69 |
|
| 70 |
/** Set or clear the process alarm; zero means unavailable or no prior alarm. */ |
| 71 |
public static function alarm(int $seconds): int { |
| 72 |
if (!ABJ_404_Solution_PhpRuntimeCapabilityAdapter::isFunctionAvailable('pcntl_alarm')) { |
| 73 |
return 0; |
| 74 |
} |
| 75 |
return pcntl_alarm($seconds); |
| 76 |
} |
| 77 |
} |
| 78 |
|
