diff options
Diffstat (limited to 'nsprpub/pr/src/md/windows/w32rng.c')
-rw-r--r-- | nsprpub/pr/src/md/windows/w32rng.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/nsprpub/pr/src/md/windows/w32rng.c b/nsprpub/pr/src/md/windows/w32rng.c new file mode 100644 index 0000000000..c07625eccb --- /dev/null +++ b/nsprpub/pr/src/md/windows/w32rng.c @@ -0,0 +1,80 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include <windows.h> +#include <time.h> +#include <io.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <stdio.h> +#include <primpl.h> + +static BOOL +CurrentClockTickTime(LPDWORD lpdwHigh, LPDWORD lpdwLow) +{ + LARGE_INTEGER liCount; + + if (!QueryPerformanceCounter(&liCount)) { + return FALSE; + } + + *lpdwHigh = liCount.u.HighPart; + *lpdwLow = liCount.u.LowPart; + return TRUE; +} + +extern PRSize _PR_MD_GetRandomNoise( void *buf, PRSize size ) +{ + DWORD dwHigh, dwLow, dwVal; + size_t n = 0; + size_t nBytes; + time_t sTime; + + if (size <= 0) { + return 0; + } + + CurrentClockTickTime(&dwHigh, &dwLow); + + // get the maximally changing bits first + nBytes = sizeof(dwLow) > size ? size : sizeof(dwLow); + memcpy((char *)buf, &dwLow, nBytes); + n += nBytes; + size -= nBytes; + + if (size <= 0) { + return n; + } + + nBytes = sizeof(dwHigh) > size ? size : sizeof(dwHigh); + memcpy(((char *)buf) + n, &dwHigh, nBytes); + n += nBytes; + size -= nBytes; + + if (size <= 0) { + return n; + } + + // get the number of milliseconds that have elapsed since Windows started + dwVal = GetTickCount(); + + nBytes = sizeof(dwVal) > size ? size : sizeof(dwVal); + memcpy(((char *)buf) + n, &dwVal, nBytes); + n += nBytes; + size -= nBytes; + + if (size <= 0) { + return n; + } + + // get the time in seconds since midnight Jan 1, 1970 + time(&sTime); + nBytes = sizeof(sTime) > size ? size : sizeof(sTime); + memcpy(((char *)buf) + n, &sTime, nBytes); + n += nBytes; + + return n; +} + |