summaryrefslogtreecommitdiffstats
path: root/system/libraries/Output.php
blob: b09bf2a53d4ff1ac5026d05861e7deff1176f9ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
<?php  if (!defined('BASEPATH')) exit('No direct script access allowed');
/**
 * Code Igniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		Rick Ellis
 * @copyright	Copyright (c) 2006, pMachine, Inc.
 * @license		http://www.codeignitor.com/user_guide/license.html 
 * @link		http://www.codeigniter.com
 * @since		Version 1.0
 * @filesource
 */
 
// ------------------------------------------------------------------------

/**
 * Output Class
 *
 * Responsible for sending final output to browser
 * 
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Output
 * @author		Rick Ellis
 * @link		http://www.codeigniter.com/user_guide/libraries/output.html
 */
class CI_Output {

	var $final_output;
	var $cache_expiration = 0;
	var $headers = array();

	function CI_Output()
	{
		log_message('debug', "Output Class Initialized");
	}
	
	// --------------------------------------------------------------------
	
	/**
	 * Get Output 
	 *
	 * Returns the current output string
	 *
	 * @access	public
	 * @return	string
	 */	
	function get_output()
	{
		return $this->final_output;
	}
	
	// --------------------------------------------------------------------
	
	/**
	 * Set Output 
	 *
	 * Sets the output string
	 *
	 * @access	public
	 * @param	string
	 * @return	void
	 */	
	function set_output($output)
	{
		$this->final_output = $output;
	}

	// --------------------------------------------------------------------
	
	/**
	 * Set Header 
	 *
	 * Lets you set a server header which will be outputted with the final display.
	 *
	 * Note:  If a file is cached, headers will not be sent.  We need to figure out
	 * how to permit header data to be saved with the cache data...
	 *
	 * @access	public
	 * @param	string
	 * @return	void
	 */	
	function set_header($header)
	{
		$this->headers[] = $header;
	}

	
	// --------------------------------------------------------------------
	
	/**
	 * Set Cache 
	 *
	 * @access	public
	 * @param	integer
	 * @return	void
	 */	
	function cache($time)
	{
		$this->cache_expiration = ( ! is_numeric($time)) ? 0 : $time;
	}
	
	// --------------------------------------------------------------------
	
	/**
	 * Display Output
	 *
	 * All "view" data is automatically put into this variable 
	 * by the controller class:
	 *
	 * $this->final_output
	 *
	 * This function simply echos the variable out.  It also does the following:
	 * 
	 * Stops the benchmark timer so the page rendering speed can be shown.
	 *
	 * Determines if the "memory_get_usage' function is available so that 
	 * the memory usage can be shown.
	 *
	 * @access	public
	 * @return	void
	 */		
	function _display($output = '')
	{	
		$BM =& _load_class('CI_Benchmark');
		
		if ($output == '')
		{
			$output =& $this->final_output;
		}
		
		// Do we need to write a cache file?
		if ($this->cache_expiration > 0)
		{
			$this->_write_cache($output);
		}

		// Parse out the elapsed time and memory usage, and 
		// swap the pseudo-variables with the data
		$elapsed = $BM->elapsed_time('code_igniter_start', 'code_igniter_end');		
		$memory	 = ( ! function_exists('memory_get_usage')) ? '0' : round(memory_get_usage()/1024/1024, 2).'MB';

		$output = str_replace('{memory_usage}', $memory, $output);		
		$output = str_replace('{elapsed_time}', $elapsed, $output);
		
		// Are there any server headers to send?
		if (count($this->headers) > 0)
		{
			foreach ($this->headers as $header)
			{
				@header($header);
			}
		}
		
		// Send it to the browser!
		echo $output;
		
		log_message('debug', "Final output sent to browser");
		log_message('debug', "Total execution time: ".$elapsed);		
	}
	
	// --------------------------------------------------------------------
	
	/**
	 * Write a Cache File 
	 *
	 * @access	public
	 * @return	void
	 */	
	function _write_cache($output)
	{
		$obj =& get_instance();	
		$path = $obj->config->item('cache_path');
	
		$cache_path = ($path == '') ? BASEPATH.'cache/' : $path;
		
		if ( ! is_dir($cache_path) OR ! is_writable($cache_path))
		{
			return;
		}
		
		$uri =	$obj->config->item('base_url').
				$obj->config->item('index_page').
				$obj->uri->uri_string();
		
		$cache_path .= md5($uri);

        if ( ! $fp = @fopen($cache_path, 'wb'))
        {
			log_message('error', "Unable to write ache file: ".$cache_path);
            return;
		}
		
		$expire = time() + ($this->cache_expiration * 60);
		
        flock($fp, LOCK_EX);
        fwrite($fp, $expire.'TS--->'.$output);
        flock($fp, LOCK_UN);
        fclose($fp);
		@chmod($cache_path, 0777); 

		log_message('debug', "Cache file written: ".$cache_path);
	}

	// --------------------------------------------------------------------
	
	/**
	 * Update/serve a cached file 
	 *
	 * @access	public
	 * @return	void
	 */	
	function _display_cache(&$CFG, &$RTR)
	{
		$CFG =& _load_class('CI_Config');
		$RTR =& _load_class('CI_Router');
	
		$cache_path = ($CFG->item('cache_path') == '') ? BASEPATH.'cache/' : $CFG->item('cache_path');
			
		if ( ! is_dir($cache_path) OR ! is_writable($cache_path))
		{
			return FALSE;
		}
		
		// Build the file path.  The file name is an MD5 hash of the full URI
		$uri =	$CFG->item('base_url').
				$CFG->item('index_page').
				$RTR->uri_string;
				
		$filepath = $cache_path.md5($uri);
		
		if ( ! @file_exists($filepath))
		{
			return FALSE;
		}
	
		if ( ! $fp = @fopen($filepath, 'rb'))
		{
			return FALSE;
		}
			
		flock($fp, LOCK_SH);
		
		$cache = '';
		if (filesize($filepath) > 0) 
		{
			$cache = fread($fp, filesize($filepath)); 
		}
	
		flock($fp, LOCK_UN);
		fclose($fp); 
					
		// Strip out the embedded timestamp		
		if ( ! preg_match("/(\d+TS--->)/", $cache, $match))
		{
			return FALSE;
		}
		
		// Has the file expired? If so we'll delete it.
		if (time() >= trim(str_replace('TS--->', '', $match['1'])))
		{ 		
			@unlink($filepath);
			log_message('debug', "Cache file has expired. File deleted");
			return FALSE;
		}

		// Display the cache
		$this->_display(str_replace($match['0'], '', $cache));
		log_message('debug', "Cache file is current. Sending it to browser.");		
		return TRUE;
	}

}
// END Output Class
?>