freebsd-skq/contrib/apr/misc/unix/randbyte_os2.inc
Peter Wemm 937a200089 Introduce svnlite so that we can check out our source code again.
This is actually a fully functional build except:
* All internal shared libraries are static linked to make sure there
  is no interference with ports (and to reduce build time).
* It does not have the python/perl/etc plugin or API support.
* By default, it installs as "svnlite" rather than "svn".
* If WITH_SVN added in make.conf, you get "svn".
* If WITHOUT_SVNLITE is in make.conf, this is completely disabled.

To be absolutely clear, this is not intended for any use other than
checking out freebsd source and committing, like we once did with cvs.

It should be usable for small scale local repositories that don't
need the python/perl plugin architecture.
2013-06-18 02:53:45 +00:00

124 lines
3.6 KiB
C++

/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* The high resolution timer API provides access to the hardware timer
* running at around 1.1MHz. The amount this changes in a time slice is
* varies randomly due to system events, hardware interrupts etc
*/
static UCHAR randbyte_hrtimer()
{
QWORD t1, t2;
UCHAR byte;
DosTmrQueryTime(&t1);
DosSleep(5);
DosTmrQueryTime(&t2);
byte = (t2.ulLo - t1.ulLo) & 0xFF;
byte ^= (t2.ulLo - t1.ulLo) >> 8;
return byte;
}
/* A bunch of system information like memory & process stats.
* Not highly random but every bit helps....
*/
static UCHAR randbyte_sysinfo()
{
UCHAR byte = 0;
UCHAR SysVars[100];
int b;
DosQuerySysInfo(1, QSV_FOREGROUND_PROCESS, SysVars, sizeof(SysVars));
for (b = 0; b < 100; b++) {
byte ^= SysVars[b];
}
return byte;
}
/* Similar in concept to randbyte_hrtimer() but accesses the CPU's internal
* counters which run at the CPU's MHz speed. We get separate
* idle / busy / interrupt cycle counts which should provide very good
* randomness due to interference of hardware events.
* This only works on newer CPUs (at least PPro or K6) and newer OS/2 versions
* which is why it's run-time linked.
*/
static APIRET APIENTRY(*DosPerfSysCall) (ULONG ulCommand, ULONG ulParm1,
ULONG ulParm2, ULONG ulParm3) = NULL;
static HMODULE hDoscalls = 0;
#define CMD_KI_RDCNT (0x63)
typedef struct _CPUUTIL {
ULONG ulTimeLow; /* Low 32 bits of time stamp */
ULONG ulTimeHigh; /* High 32 bits of time stamp */
ULONG ulIdleLow; /* Low 32 bits of idle time */
ULONG ulIdleHigh; /* High 32 bits of idle time */
ULONG ulBusyLow; /* Low 32 bits of busy time */
ULONG ulBusyHigh; /* High 32 bits of busy time */
ULONG ulIntrLow; /* Low 32 bits of interrupt time */
ULONG ulIntrHigh; /* High 32 bits of interrupt time */
} CPUUTIL;
static UCHAR randbyte_perf()
{
UCHAR byte = 0;
CPUUTIL util;
int c;
if (hDoscalls == 0) {
char failed_module[20];
ULONG rc;
rc = DosLoadModule(failed_module, sizeof(failed_module), "DOSCALLS",
&hDoscalls);
if (rc == 0) {
rc = DosQueryProcAddr(hDoscalls, 976, NULL, (PFN *)&DosPerfSysCall);
if (rc) {
DosPerfSysCall = NULL;
}
}
}
if (DosPerfSysCall) {
if (DosPerfSysCall(CMD_KI_RDCNT, (ULONG)&util, 0, 0) == 0) {
for (c = 0; c < sizeof(util); c++) {
byte ^= ((UCHAR *)&util)[c];
}
}
else {
DosPerfSysCall = NULL;
}
}
return byte;
}
static UCHAR randbyte()
{
return randbyte_hrtimer() ^ randbyte_sysinfo() ^ randbyte_perf();
}