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author | Steve Block <steveblock@google.com> | 2011-05-13 06:44:40 -0700 |
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committer | Android (Google) Code Review <android-gerrit@google.com> | 2011-05-13 06:44:40 -0700 |
commit | 08014c20784f3db5df3a89b73cce46037b77eb59 (patch) | |
tree | 47749210d31e19e6e2f64036fa8fae2ad693476f /Source/JavaScriptCore/wtf/RandomNumber.cpp | |
parent | 860220379e56aeb66424861ad602b07ee22b4055 (diff) | |
parent | 4c3661f7918f8b3f139f824efb7855bedccb4c94 (diff) | |
download | external_webkit-08014c20784f3db5df3a89b73cce46037b77eb59.zip external_webkit-08014c20784f3db5df3a89b73cce46037b77eb59.tar.gz external_webkit-08014c20784f3db5df3a89b73cce46037b77eb59.tar.bz2 |
Merge changes Ide388898,Ic49f367c,I1158a808,Iacb6ca5d,I2100dd3a,I5c1abe54,Ib0ef9902,I31dbc523,I570314b3
* changes:
Merge WebKit at r75315: Update WebKit version
Merge WebKit at r75315: Add FrameLoaderClient PageCache stubs
Merge WebKit at r75315: Stub out AXObjectCache::remove()
Merge WebKit at r75315: Fix ImageBuffer
Merge WebKit at r75315: Fix PluginData::initPlugins()
Merge WebKit at r75315: Fix conflicts
Merge WebKit at r75315: Fix Makefiles
Merge WebKit at r75315: Move Android-specific WebCore files to Source
Merge WebKit at r75315: Initial merge by git.
Diffstat (limited to 'Source/JavaScriptCore/wtf/RandomNumber.cpp')
-rw-r--r-- | Source/JavaScriptCore/wtf/RandomNumber.cpp | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/wtf/RandomNumber.cpp b/Source/JavaScriptCore/wtf/RandomNumber.cpp new file mode 100644 index 0000000..0c45416 --- /dev/null +++ b/Source/JavaScriptCore/wtf/RandomNumber.cpp @@ -0,0 +1,123 @@ +/* + * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved. + * (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY + * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "config.h" +#include "RandomNumber.h" + +#include "RandomNumberSeed.h" + +#include <limits> +#include <limits.h> +#include <stdint.h> +#include <stdlib.h> + +#if OS(WINCE) +extern "C" { +#include "wince/mt19937ar.c" +} +#endif + +#if PLATFORM(BREWMP) +#include <AEEAppGen.h> +#include <AEESource.h> +#include <AEEStdLib.h> +#include <wtf/brew/RefPtrBrew.h> +#include <wtf/brew/ShellBrew.h> +#endif + +namespace WTF { + +double randomNumber() +{ +#if !ENABLE(JSC_MULTIPLE_THREADS) + static bool s_initialized = false; + if (!s_initialized) { + initializeRandomNumberGenerator(); + s_initialized = true; + } +#endif + +#if COMPILER(MSVC) && defined(_CRT_RAND_S) + uint32_t bits; + rand_s(&bits); + return static_cast<double>(bits) / (static_cast<double>(std::numeric_limits<uint32_t>::max()) + 1.0); +#elif OS(DARWIN) + uint32_t bits = arc4random(); + return static_cast<double>(bits) / (static_cast<double>(std::numeric_limits<uint32_t>::max()) + 1.0); +#elif OS(UNIX) + uint32_t part1 = random() & (RAND_MAX - 1); + uint32_t part2 = random() & (RAND_MAX - 1); + // random only provides 31 bits + uint64_t fullRandom = part1; + fullRandom <<= 31; + fullRandom |= part2; + + // Mask off the low 53bits + fullRandom &= (1LL << 53) - 1; + return static_cast<double>(fullRandom)/static_cast<double>(1LL << 53); +#elif OS(WINCE) + return genrand_res53(); +#elif OS(WINDOWS) + uint32_t part1 = rand() & (RAND_MAX - 1); + uint32_t part2 = rand() & (RAND_MAX - 1); + uint32_t part3 = rand() & (RAND_MAX - 1); + uint32_t part4 = rand() & (RAND_MAX - 1); + // rand only provides 15 bits on Win32 + uint64_t fullRandom = part1; + fullRandom <<= 15; + fullRandom |= part2; + fullRandom <<= 15; + fullRandom |= part3; + fullRandom <<= 15; + fullRandom |= part4; + + // Mask off the low 53bits + fullRandom &= (1LL << 53) - 1; + return static_cast<double>(fullRandom)/static_cast<double>(1LL << 53); +#elif PLATFORM(BREWMP) + uint32_t bits; + RefPtr<ISource> randomSource = createRefPtrInstance<ISource>(AEECLSID_RANDOM); + ISOURCE_Read(randomSource.get(), reinterpret_cast<char*>(&bits), 4); + + return static_cast<double>(bits) / (static_cast<double>(std::numeric_limits<uint32_t>::max()) + 1.0); +#else + uint32_t part1 = rand() & (RAND_MAX - 1); + uint32_t part2 = rand() & (RAND_MAX - 1); + // rand only provides 31 bits, and the low order bits of that aren't very random + // so we take the high 26 bits of part 1, and the high 27 bits of part2. + part1 >>= 5; // drop the low 5 bits + part2 >>= 4; // drop the low 4 bits + uint64_t fullRandom = part1; + fullRandom <<= 27; + fullRandom |= part2; + + // Mask off the low 53bits + fullRandom &= (1LL << 53) - 1; + return static_cast<double>(fullRandom)/static_cast<double>(1LL << 53); +#endif +} + +} |