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diff --git a/toolkit/crashreporter/google-breakpad/src/common/linux/crc32.cc b/toolkit/crashreporter/google-breakpad/src/common/linux/crc32.cc
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+// Copyright 2014 Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * 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.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "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 THE COPYRIGHT
+// OWNER 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 "common/linux/crc32.h"
+
+namespace google_breakpad {
+
+// This implementation is based on the sample implementation in RFC 1952.
+
+// CRC32 polynomial, in reversed form.
+// See RFC 1952, or http://en.wikipedia.org/wiki/Cyclic_redundancy_check
+static const uint32_t kCrc32Polynomial = 0xEDB88320;
+static uint32_t kCrc32Table[256] = { 0 };
+
+#define arraysize(f) (sizeof(f) / sizeof(*f))
+
+static void EnsureCrc32TableInited() {
+ if (kCrc32Table[arraysize(kCrc32Table) - 1])
+ return; // already inited
+ for (uint32_t i = 0; i < arraysize(kCrc32Table); ++i) {
+ uint32_t c = i;
+ for (size_t j = 0; j < 8; ++j) {
+ if (c & 1) {
+ c = kCrc32Polynomial ^ (c >> 1);
+ } else {
+ c >>= 1;
+ }
+ }
+ kCrc32Table[i] = c;
+ }
+}
+
+uint32_t UpdateCrc32(uint32_t start, const void* buf, size_t len) {
+ EnsureCrc32TableInited();
+
+ uint32_t c = start ^ 0xFFFFFFFF;
+ const uint8_t* u = static_cast<const uint8_t*>(buf);
+ for (size_t i = 0; i < len; ++i) {
+ c = kCrc32Table[(c ^ u[i]) & 0xFF] ^ (c >> 8);
+ }
+ return c ^ 0xFFFFFFFF;
+}
+
+} // namespace google_breakpad