summaryrefslogtreecommitdiffstats
path: root/nsprpub/pr/src/md/windows/w32rng.c
diff options
context:
space:
mode:
Diffstat (limited to 'nsprpub/pr/src/md/windows/w32rng.c')
-rw-r--r--nsprpub/pr/src/md/windows/w32rng.c75
1 files changed, 75 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 000000000..633ae0da5
--- /dev/null
+++ b/nsprpub/pr/src/md/windows/w32rng.c
@@ -0,0 +1,75 @@
+/* -*- 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;
+}
+