xref: /PHP-7.0/ext/standard/uniqid.c (revision 478f119a)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 7                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2017 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 	zend_string *uniqid;
53 	int sec, usec;
54 	size_t prefix_len = 0;
55 	struct timeval tv;
56 
57 	if (zend_parse_parameters(ZEND_NUM_ARGS(), "|sb", &prefix, &prefix_len,
58 							  &more_entropy)) {
59 		return;
60 	}
61 
62 #if HAVE_USLEEP && !defined(PHP_WIN32)
63 	if (!more_entropy) {
64 #if defined(__CYGWIN__)
65 		php_error_docref(NULL, E_WARNING, "You must use 'more entropy' under CYGWIN");
66 		RETURN_FALSE;
67 #else
68 		usleep(1);
69 #endif
70 	}
71 #endif
72 	gettimeofday((struct timeval *) &tv, (struct timezone *) NULL);
73 	sec = (int) tv.tv_sec;
74 	usec = (int) (tv.tv_usec % 0x100000);
75 
76 	/* The max value usec can have is 0xF423F, so we use only five hex
77 	 * digits for usecs.
78 	 */
79 	if (more_entropy) {
80 		uniqid = strpprintf(0, "%s%08x%05x%.8F", prefix, sec, usec, php_combined_lcg() * 10);
81 	} else {
82 		uniqid = strpprintf(0, "%s%08x%05x", prefix, sec, usec);
83 	}
84 
85 	RETURN_STR(uniqid);
86 }
87 #endif
88 /* }}} */
89 
90 /*
91  * Local variables:
92  * tab-width: 4
93  * c-basic-offset: 4
94  * End:
95  * vim600: sw=4 ts=4 fdm=marker
96  * vim<600: sw=4 ts=4
97  */
98