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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/common/linux/memory_mapped_file.h')
-rw-r--r-- | toolkit/crashreporter/google-breakpad/src/common/linux/memory_mapped_file.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/toolkit/crashreporter/google-breakpad/src/common/linux/memory_mapped_file.h b/toolkit/crashreporter/google-breakpad/src/common/linux/memory_mapped_file.h new file mode 100644 index 000000000..fa660cc91 --- /dev/null +++ b/toolkit/crashreporter/google-breakpad/src/common/linux/memory_mapped_file.h @@ -0,0 +1,87 @@ +// 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_mapped_file.h: Define the google_breakpad::MemoryMappedFile +// class, which maps a file into memory for read-only access. + +#ifndef COMMON_LINUX_MEMORY_MAPPED_FILE_H_ +#define COMMON_LINUX_MEMORY_MAPPED_FILE_H_ + +#include <stddef.h> +#include "common/basictypes.h" +#include "common/memory_range.h" + +namespace google_breakpad { + +// A utility class for mapping a file into memory for read-only access of +// the file content. Its implementation avoids calling into libc functions +// by directly making system calls for open, close, mmap, and munmap. +class MemoryMappedFile { + public: + MemoryMappedFile(); + + // Constructor that calls Map() to map a file at |path| into memory. + // If Map() fails, the object behaves as if it is default constructed. + MemoryMappedFile(const char* path, size_t offset); + + ~MemoryMappedFile(); + + // Maps a file at |path| into memory, which can then be accessed via + // content() as a MemoryRange object or via data(), and returns true on + // success. Mapping an empty file will succeed but with data() and size() + // returning NULL and 0, respectively. An existing mapping is unmapped + // before a new mapping is created. + bool Map(const char* path, size_t offset); + + // Unmaps the memory for the mapped file. It's a no-op if no file is + // mapped. + void Unmap(); + + // Returns a MemoryRange object that covers the memory for the mapped + // file. The MemoryRange object is empty if no file is mapped. + const MemoryRange& content() const { return content_; } + + // Returns a pointer to the beginning of the memory for the mapped file. + // or NULL if no file is mapped or the mapped file is empty. + const void* data() const { return content_.data(); } + + // Returns the size in bytes of the mapped file, or zero if no file + // is mapped. + size_t size() const { return content_.length(); } + + private: + // Mapped file content as a MemoryRange object. + MemoryRange content_; + + DISALLOW_COPY_AND_ASSIGN(MemoryMappedFile); +}; + +} // namespace google_breakpad + +#endif // COMMON_LINUX_MEMORY_MAPPED_FILE_H_ |