Support running on non-TTY and closing STDIN and STDOUT streams

examples/01-periodic.php

@@ -29,4 +29,10 @@
     $stdio->end();
 });
 
+// input already closed on program start, exit immediately
+if (!$stdio->isReadable()) {
+    $loop->cancelTimer($timer);
+    $stdio->end();
+}
+
 $loop->run();

src/Stdin.php

@@ -2,7 +2,6 @@
 
 namespace Clue\React\Stdio;
 
-use React\Stream\ReadableStream;
 use React\Stream\Stream;
 use React\EventLoop\LoopInterface;
 
@@ -13,40 +12,77 @@ class Stdin extends Stream
 
     public function __construct(LoopInterface $loop)
     {
+        // STDIN not defined ("php -a") or already closed (`fclose(STDIN)`)
+        if (!defined('STDIN') || !is_resource(STDIN)) {
+            parent::__construct(fopen('php://memory', 'r'), $loop);
+            return $this->close();
+        }
+
         parent::__construct(STDIN, $loop);
-    }
 
-    public function resume()
-    {
-        if ($this->oldMode === null) {
+        // support starting program with closed STDIN ("example.php 0<&-")
+        // the stream is a valid resource and is not EOF, but fstat fails
+        if (fstat(STDIN) === false) {
+            return $this->close();
+        }
+
+        if ($this->isTty()) {
             $this->oldMode = shell_exec('stty -g');
 
             // Disable icanon (so we can fread each keypress) and echo (we'll do echoing here instead)
             shell_exec('stty -icanon -echo');
-
-            parent::resume();
         }
     }
 
-    public function pause()
+    public function close()
+    {
+        $this->restore();
+        parent::close();
+    }
+
+    public function __destruct()
     {
-        if ($this->oldMode !== null) {
+        $this->restore();
+    }
+
+    private function restore()
+    {
+        if ($this->oldMode !== null && $this->isTty()) {
             // Reset stty so it behaves normally again
             shell_exec(sprintf('stty %s', $this->oldMode));
-
             $this->oldMode = null;
-            parent::pause();
         }
     }
 
-    public function close()
+    /**
+     * @return bool
+     * @codeCoverageIgnore
+     */
+    private function isTty()
     {
-        $this->pause();
-        parent::close();
-    }
+        if (PHP_VERSION_ID >= 70200) {
+            // Prefer `stream_isatty()` (available as of PHP 7.2 only)
+            return stream_isatty(STDIN);
+        } elseif (function_exists('posix_isatty')) {
+            // Otherwise use `posix_isatty` if available (requires `ext-posix`)
+            return posix_isatty(STDIN);
+        }
 
-    public function __destruct()
-    {
-        $this->pause();
+        // otherwise try to guess based on stat file mode and device major number
+        // Must be special character device: ($mode & S_IFMT) === S_IFCHR
+        // And device major number must be allocated to TTYs (2-5 and 128-143)
+        // For what it's worth, checking for device gid 5 (tty) is less reliable.
+        // @link http://man7.org/linux/man-pages/man7/inode.7.html
+        // @link https://www.kernel.org/doc/html/v4.11/admin-guide/devices.html#terminal-devices
+        if (is_resource(STDIN)) {
+            $stat = fstat(STDIN);
+            $mode = isset($stat['mode']) ? ($stat['mode'] & 0170000) : 0;
+            $major = isset($stat['dev']) ? (($stat['dev'] >> 8) & 0xff) : 0;
+
+            if ($mode === 0020000 && $major >= 2 && $major <= 143 && ($major <=5 || $major >= 128)) {
+                return true;
+            }
+        }
+        return false;
     }
 }

src/Stdio.php

@@ -26,7 +26,7 @@ public function __construct(LoopInterface $loop, ReadableStreamInterface $input
         }
 
         if ($output === null) {
-            $output = new Stdout(STDOUT);
+            $output = new Stdout();
         }
 
         if ($readline === null) {

src/Stdout.php

@@ -6,10 +6,21 @@
 
 class Stdout extends WritableStream
 {
+    public function __construct()
+    {
+        // STDOUT not defined ("php -a") or already closed (`fclose(STDOUT)`)
+        if (!defined('STDOUT') || !is_resource(STDOUT)) {
+            return $this->close();
+        }
+    }
+
     public function write($data)
     {
-        // TODO: use non-blocking output instead
+        if ($this->closed) {
+            return false;
+        }
 
+        // TODO: use non-blocking output instead
         fwrite(STDOUT, $data);
 
         return true;

tests/FunctionalExampleTest.php

@@ -0,0 +1,84 @@
+<?php
+
+class FunctionalExampleTest extends TestCase
+{
+    public function testPeriodicExampleWithPipedInputEndsBecauseInputEnds()
+    {
+        $output = $this->execExample('echo hello | php 01-periodic.php');
+
+        $this->assertContains('you just said: hello\n', $output);
+    }
+
+    public function testPeriodicExampleWithNullInputQuitsImmediately()
+    {
+        $output = $this->execExample('php 01-periodic.php < /dev/null');
+
+        $this->assertNotContains('you just said:', $output);
+    }
+
+    public function testPeriodicExampleWithNoInputQuitsImmediately()
+    {
+        $output = $this->execExample('true | php 01-periodic.php');
+
+        $this->assertNotContains('you just said:', $output);
+    }
+
+    public function testPeriodicExampleWithSleepNoInputQuitsOnEnd()
+    {
+        $output = $this->execExample('sleep 0.1 | php 01-periodic.php');
+
+        $this->assertNotContains('you just said:', $output);
+    }
+
+    public function testPeriodicExampleWithClosedInputQuitsImmediately()
+    {
+        $output = $this->execExample('php 01-periodic.php <&-');
+
+        if (strpos($output, 'said') !== false) {
+            $this->markTestIncomplete('Your platform exhibits a closed STDIN bug, this may need some further debugging');
+        }
+
+        $this->assertNotContains('you just said:', $output);
+    }
+
+    public function testStubShowStdinIsReadableByDefault()
+    {
+        $output = $this->execExample('php ../tests/stub/01-check-stdin.php');
+
+        $this->assertContains('YES', $output);
+    }
+
+    public function testStubCanCloseStdinAndIsNotReadable()
+    {
+        $output = $this->execExample('php ../tests/stub/02-close-stdin.php');
+
+        $this->assertContains('NO', $output);
+    }
+
+    public function testStubCanCloseStdoutAndIsNotWritable()
+    {
+        $output = $this->execExample('php ../tests/stub/03-close-stdout.php 2>&1');
+
+        $this->assertEquals('', $output);
+    }
+
+    public function testPeriodicExampleViaInteractiveModeQuitsImmediately()
+    {
+        if (defined('HHVM_VERSION')) {
+            $this->markTestSkipped('Skipped interactive mode on HHVM');
+        }
+
+        $output = $this->execExample('echo "require(\"01-periodic.php\");" | php -a');
+
+        // starts with either "Interactive mode enabled" or "Interactive shell"
+        $this->assertStringStartsWith('Interactive ', $output);
+        $this->assertNotContains('you just said:', $output);
+    }
+
+    private function execExample($command)
+    {
+        chdir(__DIR__ . '/../examples/');
+
+        return shell_exec($command);
+    }
+}

tests/stub/01-check-stdin.php

@@ -0,0 +1,12 @@
+<?php
+
+use Clue\React\Stdio\Stdio;
+
+require __DIR__ . '/../../vendor/autoload.php';
+
+$loop = React\EventLoop\Factory::create();
+
+$stdio = new Stdio($loop);
+$stdio->end($stdio->isReadable() ? 'YES' : 'NO');
+
+$loop->run();

tests/stub/02-close-stdin.php

@@ -0,0 +1,13 @@
+<?php
+
+use Clue\React\Stdio\Stdio;
+
+require __DIR__ . '/../../vendor/autoload.php';
+
+$loop = React\EventLoop\Factory::create();
+
+fclose(STDIN);
+$stdio = new Stdio($loop);
+$stdio->end($stdio->isReadable() ? 'YES' : 'NO');
+
+$loop->run();

tests/stub/03-close-stdout.php

@@ -0,0 +1,16 @@
+<?php
+
+use Clue\React\Stdio\Stdio;
+
+require __DIR__ . '/../../vendor/autoload.php';
+
+$loop = React\EventLoop\Factory::create();
+
+fclose(STDOUT);
+$stdio = new Stdio($loop);
+if ($stdio->isWritable()) {
+    throw new \RuntimeException('Not writable');
+}
+$stdio->close();
+
+$loop->run();