The Tor Browser: comparison toolkit/crashreporter/google-breakpad/src/common/memory

--1:000000000000
+:afc8a2f6eb0e
+// Copyright (c) 2011, 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.
+// memory_range.h: Define the google_breakpad::MemoryRange class, which
+// is a lightweight wrapper with a pointer and a length to encapsulate
+// a contiguous range of memory.
+#ifndef COMMON_MEMORY_RANGE_H_
+#define COMMON_MEMORY_RANGE_H_
+#include <stddef.h>
+#include "google_breakpad/common/breakpad_types.h"
+namespace google_breakpad {
+// A lightweight wrapper with a pointer and a length to encapsulate a
+// contiguous range of memory. It provides helper methods for checked
+// access of a subrange of the memory. Its implemementation does not
+// allocate memory or call into libc functions, and is thus safer to use
+// in a crashed environment.
+class MemoryRange {
+public:
+MemoryRange() : data_(NULL), length_(0) {}
+MemoryRange(const void* data, size_t length) {
+Set(data, length);
+}
+// Returns true if this memory range contains no data.
+bool IsEmpty() const {
+// Set() guarantees that |length_| is zero if |data_| is NULL.
+return length_ == 0;
+}
+// Resets to an empty range.
+void Reset() {
+data_ = NULL;
+length_ = 0;
+}
+// Sets this memory range to point to |data| and its length to |length|.
+void Set(const void* data, size_t length) {
+data_ = reinterpret_cast<const uint8_t*>(data);
+// Always set |length_| to zero if |data_| is NULL.
+length_ = data ? length : 0;
+}
+// Returns true if this range covers a subrange of |sub_length| bytes
+// at |sub_offset| bytes of this memory range, or false otherwise.
+bool Covers(size_t sub_offset, size_t sub_length) const {
+// The following checks verify that:
+// 1. sub_offset is within [ 0 .. length_ - 1 ]
+// 2. sub_offset + sub_length is within
+//    [ sub_offset .. length_ ]
+return sub_offset < length_ &&
+sub_offset + sub_length >= sub_offset &&
+sub_offset + sub_length <= length_;
+}
+// Returns a raw data pointer to a subrange of |sub_length| bytes at
+// |sub_offset| bytes of this memory range, or NULL if the subrange
+// is out of bounds.
+const void* GetData(size_t sub_offset, size_t sub_length) const {
+return Covers(sub_offset, sub_length) ? (data_ + sub_offset) : NULL;
+}
+// Same as the two-argument version of GetData() but uses sizeof(DataType)
+// as the subrange length and returns an |DataType| pointer for convenience.
+template <typename DataType>
+const DataType* GetData(size_t sub_offset) const {
+return reinterpret_cast<const DataType*>(
+GetData(sub_offset, sizeof(DataType)));
+}
+// Returns a raw pointer to the |element_index|-th element of an array
+// of elements of length |element_size| starting at |sub_offset| bytes
+// of this memory range, or NULL if the element is out of bounds.
+const void* GetArrayElement(size_t element_offset,
+size_t element_size,
+unsigned element_index) const {
+size_t sub_offset = element_offset + element_index * element_size;
+return GetData(sub_offset, element_size);
+}
+// Same as the three-argument version of GetArrayElement() but deduces
+// the element size using sizeof(ElementType) and returns an |ElementType|
+// pointer for convenience.
+template <typename ElementType>
+const ElementType* GetArrayElement(size_t element_offset,
+unsigned element_index) const {
+return reinterpret_cast<const ElementType*>(
+GetArrayElement(element_offset, sizeof(ElementType), element_index));
+}
+// Returns a subrange of |sub_length| bytes at |sub_offset| bytes of
+// this memory range, or an empty range if the subrange is out of bounds.
+MemoryRange Subrange(size_t sub_offset, size_t sub_length) const {
+return Covers(sub_offset, sub_length) ?
+MemoryRange(data_ + sub_offset, sub_length) : MemoryRange();
+}
+// Returns a pointer to the beginning of this memory range.
+const uint8_t* data() const { return data_; }
+// Returns the length, in bytes, of this memory range.
+size_t length() const { return length_; }
+private:
+// Pointer to the beginning of this memory range.
+const uint8_t* data_;
+// Length, in bytes, of this memory range.
+size_t length_;
+};
+}  // namespace google_breakpad
+#endif  // COMMON_MEMORY_RANGE_H_

The Tor Browser / file comparison

comparison: toolkit/crashreporter/google-breakpad/src/common/memory_range.h

toolkit/crashreporter/google-breakpad/src/common/memory_range.h