1 files changed, 81 insertions, 0 deletions
diff --git a/nsprpub/pr/src/md/os2/os2inrval.c b/nsprpub/pr/src/md/os2/os2inrval.c
new file mode 100644
index 0000000000..bd283f06d9
--- /dev/null
+++ b/nsprpub/pr/src/md/os2/os2inrval.c
@@ -0,0 +1,81 @@
+/* -*- 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/. */
+
+/*
+ * OS/2 interval timers
+ *
+ */
+
+#include "primpl.h"
+
+static PRBool useHighResTimer = PR_FALSE;
+PRIntervalTime _os2_ticksPerSec = -1;
+PRIntn _os2_bitShift = 0;
+PRInt32 _os2_highMask = 0;
+
+void
+_PR_MD_INTERVAL_INIT()
+{
+    char *envp;
+    ULONG timerFreq;
+    APIRET rc;
+
+    if ((envp = getenv("NSPR_OS2_NO_HIRES_TIMER")) != NULL) {
+        if (atoi(envp) == 1) {
+            return;
+        }
+    }
+
+    timerFreq = 0; /* OS/2 high-resolution timer frequency in Hz */
+    rc = DosTmrQueryFreq(&timerFreq);
+    if (NO_ERROR == rc) {
+        useHighResTimer = PR_TRUE;
+        PR_ASSERT(timerFreq != 0);
+        while (timerFreq > PR_INTERVAL_MAX) {
+            timerFreq >>= 1;
+            _os2_bitShift++;
+            _os2_highMask = (_os2_highMask << 1)+1;
+        }
+
+        _os2_ticksPerSec = timerFreq;
+        PR_ASSERT(_os2_ticksPerSec > PR_INTERVAL_MIN);
+    }
+}
+
+PRIntervalTime
+_PR_MD_GET_INTERVAL()
+{
+    if (useHighResTimer) {
+        QWORD timestamp;
+        PRInt32 top;
+        APIRET rc = DosTmrQueryTime(&timestamp);
+        if (NO_ERROR != rc) {
+            return -1;
+        }
+        /* Sadly, nspr requires the interval to range from 1000 ticks per
+         * second to only 100000 ticks per second. DosTmrQueryTime is too
+         * high resolution...
+         */
+        top = timestamp.ulHi & _os2_highMask;
+        top = top << (32 - _os2_bitShift);
+        timestamp.ulLo = timestamp.ulLo >> _os2_bitShift;
+        timestamp.ulLo = timestamp.ulLo + top;
+        return (PRUint32)timestamp.ulLo;
+    } else {
+        ULONG msCount = -1;
+        DosQuerySysInfo(QSV_MS_COUNT, QSV_MS_COUNT, &msCount, sizeof(msCount));
+        return msCount;
+    }
+}
+
+PRIntervalTime
+_PR_MD_INTERVAL_PER_SEC()
+{
+    if (useHighResTimer) {
+        return _os2_ticksPerSec;
+    } else {
+        return 1000;
+    }
+}