Add bench and test for SkRefCnt.

http://codereview.appspot.com/6195071/

This also adds a cross platform SkThread for testing purposes.


git-svn-id: http://skia.googlecode.com/svn/trunk@3921 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 136 insertions, 0 deletions

diff --git a/src/utils/SkThreadUtils_win.cpp b/src/utils/SkThreadUtils_win.cpp
new file mode 100644
index 0000000000..208ffded1b
--- /dev/null
+++ b/src/utils/SkThreadUtils_win.cpp
@@ -0,0 +1,136 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkTypes.h"
+
+#include "SkThreadUtils.h"
+#include "SkThreadUtils_win.h"
+
+SkThread_WinData::SkThread_WinData(SkThread::entryPointProc entryPoint, void* data)
+    : fHandle(NULL)
+    , fParam(data)
+    , fThreadId(0)
+    , fEntryPoint(entryPoint)
+    , fStarted(false)
+{
+    fCancelEvent = CreateEvent(
+        NULL,  // default security attributes
+        false, //auto reset
+        false, //not signaled
+        NULL); //no name
+}
+
+SkThread_WinData::~SkThread_WinData() {
+    CloseHandle(fCancelEvent);
+}
+
+static DWORD WINAPI thread_start(LPVOID data) {
+    SkThread_WinData* winData = static_cast<SkThread_WinData*>(data);
+
+    //See if this thread was canceled before starting.
+    if (WaitForSingleObject(winData->fCancelEvent, 0) == WAIT_OBJECT_0) {
+        return 0;
+    }
+
+    winData->fEntryPoint(winData->fParam);
+    return 0;
+}
+
+SkThread::SkThread(entryPointProc entryPoint, void* data) {
+    SkThread_WinData* winData = new SkThread_WinData(entryPoint, data);
+    fData = winData;
+
+    if (NULL == winData->fCancelEvent) {
+        return;
+    }
+
+    winData->fHandle = CreateThread(
+        NULL,                   // default security attributes
+        0,                      // use default stack size
+        thread_start,           // thread function name (proxy)
+        winData,                // argument to thread function (proxy args)
+        CREATE_SUSPENDED,       // create suspended so affinity can be set
+        &winData->fThreadId);   // returns the thread identifier
+}
+
+SkThread::~SkThread() {
+    if (fData != NULL) {
+        SkThread_WinData* winData = static_cast<SkThread_WinData*>(fData);
+        // If created thread but start was never called, kill the thread.
+        if (winData->fHandle != NULL && !winData->fStarted) {
+            if (SetEvent(winData->fCancelEvent) != 0) {
+                if (this->start()) {
+                    this->join();
+                }
+            } else {
+                //kill with prejudice
+                TerminateThread(winData->fHandle, -1);
+            }
+        }
+        delete winData;
+    }
+}
+
+bool SkThread::start() {
+    SkThread_WinData* winData = static_cast<SkThread_WinData*>(fData);
+    if (NULL == winData->fHandle) {
+        return false;
+    }
+
+    if (winData->fStarted) {
+        return false;
+    }
+    winData->fStarted = -1 != ResumeThread(winData->fHandle);
+    return winData->fStarted;
+}
+
+void SkThread::join() {
+    SkThread_WinData* winData = static_cast<SkThread_WinData*>(fData);
+    if (NULL == winData->fHandle || !winData->fStarted) {
+        return;
+    }
+
+    WaitForSingleObject(winData->fHandle, INFINITE);
+}
+
+static unsigned int num_bits_set(DWORD_PTR mask) {
+    unsigned int count;
+    for (count = 0; mask; ++count) {
+        mask &= mask - 1;
+    }
+    return count;
+}
+
+static unsigned int nth_set_bit(unsigned int n, DWORD_PTR mask) {
+    n %= num_bits_set(mask);
+    for (unsigned int setBitsSeen = 0, currentBit = 0; true; ++currentBit) {
+        if (mask & (1 << currentBit)) {
+            ++setBitsSeen;
+            if (setBitsSeen > n) {
+                return currentBit;
+            }
+        }
+    }
+}
+
+bool SkThread::setProcessorAffinity(unsigned int processor) {
+    SkThread_WinData* winData = static_cast<SkThread_WinData*>(fData);
+    if (NULL == winData->fHandle) {
+        return false;
+    }
+
+    DWORD_PTR processAffinityMask;
+    DWORD_PTR systemAffinityMask;
+    if (0 == GetProcessAffinityMask(GetCurrentProcess(),
+                                    &processAffinityMask,
+                                    &systemAffinityMask)) {
+        return false;
+    }
+
+    DWORD_PTR threadAffinityMask = 1 << nth_set_bit(processor, processAffinityMask);
+    return 0 != SetThreadAffinityMask(winData->fHandle, threadAffinityMask);
+}