xref: /PHP-5.6/ext/standard/uniqid.c (revision 49493a2d)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 5                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2016 The PHP Group                                |
6    +----------------------------------------------------------------------+
7    | This source file is subject to version 3.01 of the PHP license,      |
8    | that is bundled with this package in the file LICENSE, and is        |
9    | available through the world-wide-web at the following url:           |
10    | http://www.php.net/license/3_01.txt                                  |
11    | If you did not receive a copy of the PHP license and are unable to   |
12    | obtain it through the world-wide-web, please send a note to          |
13    | license@php.net so we can mail you a copy immediately.               |
14    +----------------------------------------------------------------------+
15    | Author: Stig S�ther Bakken <ssb@php.net>                             |
16    +----------------------------------------------------------------------+
17  */
18 
19 /* $Id$ */
20 
21 #include "php.h"
22 
23 #include <stdlib.h>
24 #if HAVE_UNISTD_H
25 #include <unistd.h>
26 #endif
27 
28 #include <string.h>
29 #include <errno.h>
30 
31 #include <stdio.h>
32 #ifdef PHP_WIN32
33 #include "win32/time.h"
34 #else
35 #include <sys/time.h>
36 #endif
37 
38 #include "php_lcg.h"
39 #include "uniqid.h"
40 
41 /* {{{ proto string uniqid([string prefix [, bool more_entropy]])
42    Generates a unique ID */
43 #ifdef HAVE_GETTIMEOFDAY
PHP_FUNCTION(uniqid)44 PHP_FUNCTION(uniqid)
45 {
46 	char *prefix = "";
47 #if defined(__CYGWIN__)
48 	zend_bool more_entropy = 1;
49 #else
50 	zend_bool more_entropy = 0;
51 #endif
52 	char *uniqid;
53 	int sec, usec, prefix_len = 0;
54 	struct timeval tv;
55 
56 	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "|sb", &prefix, &prefix_len,
57 							  &more_entropy)) {
58 		return;
59 	}
60 
61 #if HAVE_USLEEP && !defined(PHP_WIN32)
62 	if (!more_entropy) {
63 #if defined(__CYGWIN__)
64 		php_error_docref(NULL TSRMLS_CC, E_WARNING, "You must use 'more entropy' under CYGWIN");
65 		RETURN_FALSE;
66 #else
67 		usleep(1);
68 #endif
69 	}
70 #endif
71 	gettimeofday((struct timeval *) &tv, (struct timezone *) NULL);
72 	sec = (int) tv.tv_sec;
73 	usec = (int) (tv.tv_usec % 0x100000);
74 
75 	/* The max value usec can have is 0xF423F, so we use only five hex
76 	 * digits for usecs.
77 	 */
78 	if (more_entropy) {
79 		spprintf(&uniqid, 0, "%s%08x%05x%.8F", prefix, sec, usec, php_combined_lcg(TSRMLS_C) * 10);
80 	} else {
81 		spprintf(&uniqid, 0, "%s%08x%05x", prefix, sec, usec);
82 	}
83 
84 	RETURN_STRING(uniqid, 0);
85 }
86 #endif
87 /* }}} */
88 
89 /*
90  * Local variables:
91  * tab-width: 4
92  * c-basic-offset: 4
93  * End:
94  * vim600: sw=4 ts=4 fdm=marker
95  * vim<600: sw=4 ts=4
96  */
97