97 lines
3.3 KiB
C++
97 lines
3.3 KiB
C++
|
// Copyright (c) 2006, Google Inc.
|
||
|
|
// All rights reserved.
|
||
|
|
//
|
||
|
|
// Redistribution and use in source and binary forms, with or without
|
||
|
|
// modification, are permitted provided that the following conditions are
|
||
|
|
// met:
|
||
|
|
//
|
||
|
|
// * Redistributions of source code must retain the above copyright
|
||
|
|
// notice, this list of conditions and the following disclaimer.
|
||
|
|
// * Redistributions in binary form must reproduce the above
|
||
|
|
// copyright notice, this list of conditions and the following disclaimer
|
||
|
|
// in the documentation and/or other materials provided with the
|
||
|
|
// distribution.
|
||
|
|
// * Neither the name of Google Inc. nor the names of its
|
||
|
|
// contributors may be used to endorse or promote products derived from
|
||
|
|
// this software without specific prior written permission.
|
||
|
|
//
|
||
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
|
||
|
|
#include "common/linux/guid_creator.h"
|
||
|
|
|
||
|
|
#include <assert.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <time.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
|
||
|
|
//
|
||
|
|
// GUIDGenerator
|
||
|
|
//
|
||
|
|
// This class is used to generate random GUID.
|
||
|
|
// Currently use random number to generate a GUID since Linux has
|
||
|
|
// no native GUID generator. This should be OK since we don't expect
|
||
|
|
// crash to happen very offen.
|
||
|
|
//
|
||
|
|
class GUIDGenerator {
|
||
|
|
public:
|
||
|
|
GUIDGenerator() {
|
||
|
|
srandom(time(NULL));
|
||
|
|
}
|
||
|
|
|
||
|
|
static u_int32_t BytesToUInt32(const u_int8_t bytes[]) {
|
||
|
|
return ((u_int32_t) bytes[0]
|
||
|
|
| ((u_int32_t) bytes[1] << 8)
|
||
|
|
| ((u_int32_t) bytes[2] << 16)
|
||
|
|
| ((u_int32_t) bytes[3] << 24));
|
||
|
|
}
|
||
|
|
|
||
|
|
static void UInt32ToBytes(u_int8_t bytes[], u_int32_t n) {
|
||
|
|
bytes[0] = n & 0xff;
|
||
|
|
bytes[1] = (n >> 8) & 0xff;
|
||
|
|
bytes[2] = (n >> 16) & 0xff;
|
||
|
|
bytes[3] = (n >> 24) & 0xff;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool CreateGUID(GUID *guid) const {
|
||
|
|
guid->data1 = random();
|
||
|
|
guid->data2 = (u_int16_t)(random());
|
||
|
|
guid->data3 = (u_int16_t)(random());
|
||
|
|
UInt32ToBytes(&guid->data4[0], random());
|
||
|
|
UInt32ToBytes(&guid->data4[4], random());
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
// Guid generator.
|
||
|
|
const GUIDGenerator kGuidGenerator;
|
||
|
|
|
||
|
|
bool CreateGUID(GUID *guid) {
|
||
|
|
return kGuidGenerator.CreateGUID(guid);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Parse guid to string.
|
||
|
|
bool GUIDToString(const GUID *guid, char *buf, int buf_len) {
|
||
|
|
// Should allow more space the the max length of GUID.
|
||
|
|
assert(buf_len > kGUIDStringLength);
|
||
|
|
int num = snprintf(buf, buf_len, kGUIDFormatString,
|
||
|
|
guid->data1, guid->data2, guid->data3,
|
||
|
|
GUIDGenerator::BytesToUInt32(&(guid->data4[0])),
|
||
|
|
GUIDGenerator::BytesToUInt32(&(guid->data4[4])));
|
||
|
|
if (num != kGUIDStringLength)
|
||
|
|
return false;
|
||
|
|
|
||
|
|
buf[num] = '\0';
|
||
|
|
return true;
|
||
|
|
}
|