[Streams] Avoid locking stdin when no input

Author: yannoff

src/IO/FStat.php

@@ -0,0 +1,136 @@
+<?php
+
+/**
+ * This file is part of the yannoff/console library
+ *
+ * (c) Yannoff (https://github.com/yannoff)
+ *
+ * @project   yannoff/console
+ * @link      https://github.com/yannoff/console
+ * @license   https://github.com/yannoff/console/blob/master/LICENSE
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Yannoff\Component\Console\IO;
+
+/**
+ * Class FStat
+ * Handle the inode file statistics
+ *
+ * @source https://stackoverflow.com/a/11327451
+ *
+ * @package Yannoff\Component\Console\IO
+ */
+class FStat
+{
+    /**
+     * Octal mode values from libc headers
+     */
+    const S_IFMT   = 0170000;
+    const S_IFIFO  = 0010000;
+    const S_IFCHR  = 0020000;
+    const S_IFDIR  = 0040000;
+    const S_IFBLK  = 0060000;
+    const S_IFREG  = 0100000;
+    const S_IFLNK  = 0120000;
+    const S_IFSOCK = 0140000;
+
+    /**
+     * Get the handle current protection mode
+     *
+     * @param resource $handle
+     *
+     * @return int
+     */
+    protected static function imode($handle)
+    {
+        $stat = fstat($handle);
+        return $stat['mode'] & self::S_IFMT;
+    }
+
+    /**
+     * Check whether the handle is a FIFO
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isFifo($handle)
+    {
+        return self::imode($handle) == self::S_IFIFO;
+    }
+
+    /**
+     * Check whether the handle is a character
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isChar($handle)
+    {
+        return self::imode($handle) == self::S_IFCHR;
+    }
+
+    /**
+     * Check whether the handle is a directory
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isDir($handle)
+    {
+        return self::imode($handle) == self::S_IFDIR;
+    }
+
+    /**
+     * Check whether the handle is a block device
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isBlock($handle)
+    {
+        return self::imode($handle) == self::S_IFBLK;
+    }
+
+    /**
+     * Check whether the handle is a regular file redirect
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isRegularFile($handle)
+    {
+        return self::imode($handle) == self::S_IFREG;
+    }
+
+    /**
+     * Check whether the handle is a symlink
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isLink($handle)
+    {
+        return self::imode($handle) == self::S_IFLNK;
+    }
+
+    /**
+     * Check whether the handle is a socket
+     *
+     * @param resource $handle
+     *
+     * @return bool
+     */
+    public static function isSocket($handle)
+    {
+        return self::imode($handle) == self::S_IFSOCK;
+    }
+}

src/IO/Stream/IOReader.php

@@ -26,7 +26,11 @@ interface IOReader extends IOStream
     /**
      * Fetch contents from the input stream
      *
+     * @param bool $interactive Whether to accept contents from user input or not
+     * If no contents are provided via a pipe or a regular file redirect, controls whether
+     * the terminal should wait for user input - until a terminating sequence is emitted
+     *
      * @return string|false The contents or **false** in case of failure
      */
-    public function read();
+    public function read($interactive = false);
 }

src/IO/Stream/StandardInput.php

@@ -37,8 +37,15 @@ class StandardInput extends Wrapper implements IOReader
     /**
      * {@inheritdoc}
      */
-    public function read()
+    public function read($interactive = false)
     {
-        return stream_get_contents($this->handle);
+        // Unless explicitly forced using the $interactive parameter,
+        // assume we only want to read from stdin when it's a piped
+        // input or a regular file redirect
+        if ($interactive || $this->isPiped() || $this->isFile()) {
+            return stream_get_contents($this->handle);
+        }
+
+        return '';
     }
 }

src/IO/Stream/Wrapper.php

@@ -18,6 +18,7 @@
 use Yannoff\Component\Console\Exception\IO\StreamLogicException;
 use Yannoff\Component\Console\Exception\UndefinedConstantException;
 use Yannoff\Component\Console\IO\ConstantAccessor;
+use Yannoff\Component\Console\IO\FStat;
 
 /**
  * Class Wrapper
@@ -90,6 +91,26 @@ public function getOpenMode()
         return $this->constant('MODE');
     }
 
+    /**
+     * Check whether the stream is a FIFO
+     *
+     * @return bool
+     */
+    public function isPiped()
+    {
+        return FStat::isFifo($this->handle);
+    }
+
+    /**
+     * Check whether the stream is a regular file redirect
+     *
+     * @return bool
+     */
+    public function isFile()
+    {
+        return FStat::isRegularFile($this->handle);
+    }
+
     /**
      * Generic getter for Wrapper child classes constants
      *

src/IO/StreamAwareTrait.php

@@ -73,12 +73,14 @@ public function ioerror($message = '', $ending = Formatter::LF)
     /**
      * Read contents from the standard input
      *
+     * @param bool $interactive Whether to accept user input
+     *
      * @return string|false The contents or **false** in case of failure
      */
-    public function ioread()
+    public function ioread($interactive = false)
     {
         $reader = StreamInitializer::getReader($this, IOStream::STDIN);
 
-        return $reader->read();
+        return $reader->read($interactive);
     }
 }