The Tor Browser: gfx/skia/trunk/src/utils/SkBitmapHasher.cpp@129ffea94266

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

     1 /*

     2  * Copyright 2012 Google Inc.

     3  *

     4  * Use of this source code is governed by a BSD-style license that can be

     5  * found in the LICENSE file.

     6  */

     8 #include "SkBitmap.h"

     9 #include "SkBitmapHasher.h"

    10 #include "SkEndian.h"

    11 #include "SkImageEncoder.h"

    13 #include "SkMD5.h"

    15 /**

    16  * Write an int32 value to a stream in little-endian order.

    17  */

    18 static void write_int32_to_buffer(uint32_t val, SkWStream* out) {

    19     val = SkEndian_SwapLE32(val);

    20     for (size_t byte = 0; byte < 4; ++byte) {

    21         out->write8((uint8_t)(val & 0xff));

    22         val = val >> 8;

    23     }

    24 }

    26 /**

    27  * Return the first 8 bytes of a bytearray, encoded as a little-endian uint64.

    28  */

    29 static inline uint64_t first_8_bytes_as_uint64(const uint8_t *bytearray) {

    30     return SkEndian_SwapLE64(*(reinterpret_cast<const uint64_t *>(bytearray)));

    31 }

    33 /*static*/ bool SkBitmapHasher::ComputeDigestInternal(const SkBitmap& bitmap, uint64_t *result) {

    34     SkMD5 out;

    36     // start with the x/y dimensions

    37     write_int32_to_buffer(SkToU32(bitmap.width()), &out);

    38     write_int32_to_buffer(SkToU32(bitmap.height()), &out);

    40     // add all the pixel data

    41     SkAutoTDelete<SkImageEncoder> enc(CreateARGBImageEncoder());

    42     if (!enc->encodeStream(&out, bitmap, SkImageEncoder::kDefaultQuality)) {

    43         return false;

    44     }

    46     SkMD5::Digest digest;

    47     out.finish(digest);

    48     *result = first_8_bytes_as_uint64(digest.data);

    49     return true;

    50 }

    52 /*static*/ bool SkBitmapHasher::ComputeDigest(const SkBitmap& bitmap, uint64_t *result) {

    53     if (ComputeDigestInternal(bitmap, result)) {

    54         return true;

    55     }

    57     // Hmm, that didn't work. Maybe if we create a new

    58     // kARGB_8888_Config version of the bitmap it will work better?

    59     SkBitmap copyBitmap;

    60     if (!bitmap.copyTo(&copyBitmap, kPMColor_SkColorType)) {

    61         return false;

    62     }

    63     return ComputeDigestInternal(copyBitmap, result);

    64 }

The Tor Browser / file revision

gfx/skia/trunk/src/utils/SkBitmapHasher.cpp@129ffea94266

gfx/skia/trunk/src/utils/SkBitmapHasher.cpp