root/standard/uniqid.c

DEFINITIONS

1. PHP_FUNCTION

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2013 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Author: Stig Sæther Bakken <ssb@php.net>                             |
   +----------------------------------------------------------------------+
 */

/* $Id$ */

#include "php.h"

#include <stdlib.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <string.h>
#include <errno.h>

#include <stdio.h>
#ifdef PHP_WIN32
#include "win32/time.h"
#else
#include <sys/time.h>
#endif

#include "php_lcg.h"
#include "uniqid.h"

/* {{{ proto string uniqid([string prefix [, bool more_entropy]])
   Generates a unique ID */
#ifdef HAVE_GETTIMEOFDAY
PHP_FUNCTION(uniqid)
{
        char *prefix = "";
#if defined(__CYGWIN__)
        zend_bool more_entropy = 1;
#else
        zend_bool more_entropy = 0;
#endif
        char *uniqid;
        int sec, usec, prefix_len = 0;
        struct timeval tv;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "|sb", &prefix, &prefix_len,
                                                          &more_entropy)) {
                return;
        }

#if HAVE_USLEEP && !defined(PHP_WIN32)
        if (!more_entropy) {
#if defined(__CYGWIN__)
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "You must use 'more entropy' under CYGWIN");
                RETURN_FALSE;
#else
                usleep(1);
#endif
        }
#endif
        gettimeofday((struct timeval *) &tv, (struct timezone *) NULL);
        sec = (int) tv.tv_sec;
        usec = (int) (tv.tv_usec % 0x100000);

        /* The max value usec can have is 0xF423F, so we use only five hex
         * digits for usecs.
         */
        if (more_entropy) {
                spprintf(&uniqid, 0, "%s%08x%05x%.8F", prefix, sec, usec, php_combined_lcg(TSRMLS_C) * 10);
        } else {
                spprintf(&uniqid, 0, "%s%08x%05x", prefix, sec, usec);
        }

        RETURN_STRING(uniqid, 0);
}
#endif
/* }}} */

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */