mirror of
https://github.com/OPM/ResInsight.git
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1761 lines
58 KiB
C++
1761 lines
58 KiB
C++
/* Copyright 2017 https://github.com/mandreyel
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy of this
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* software and associated documentation files (the "Software"), to deal in the Software
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* without restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to the following
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* conditions:
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*
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* The above copyright notice and this permission notice shall be included in all copies
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* or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
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* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
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* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
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* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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#ifndef MIO_MMAP_HEADER
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#define MIO_MMAP_HEADER
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// #include "mio/page.hpp"
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/* Copyright 2017 https://github.com/mandreyel
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy of this
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* software and associated documentation files (the "Software"), to deal in the Software
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* without restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to the following
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* conditions:
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*
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* The above copyright notice and this permission notice shall be included in all copies
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* or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
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* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
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* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
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* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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#ifndef MIO_PAGE_HEADER
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#define MIO_PAGE_HEADER
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#ifdef _WIN32
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# include <windows.h>
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#else
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# include <unistd.h>
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#endif
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namespace mio {
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/**
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* This is used by `basic_mmap` to determine whether to create a read-only or
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* a read-write memory mapping.
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*/
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enum class access_mode
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{
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read,
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write
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};
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/**
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* Determines the operating system's page allocation granularity.
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*
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* On the first call to this function, it invokes the operating system specific syscall
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* to determine the page size, caches the value, and returns it. Any subsequent call to
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* this function serves the cached value, so no further syscalls are made.
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*/
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inline size_t page_size()
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{
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static const size_t page_size = []
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{
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#ifdef _WIN32
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SYSTEM_INFO SystemInfo;
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GetSystemInfo(&SystemInfo);
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return SystemInfo.dwAllocationGranularity;
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#else
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return sysconf(_SC_PAGE_SIZE);
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#endif
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}();
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return page_size;
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}
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/**
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* Alligns `offset` to the operating's system page size such that it subtracts the
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* difference until the nearest page boundary before `offset`, or does nothing if
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* `offset` is already page aligned.
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*/
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inline size_t make_offset_page_aligned(size_t offset) noexcept
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{
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const size_t page_size_ = page_size();
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// Use integer division to round down to the nearest page alignment.
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return offset / page_size_ * page_size_;
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}
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} // namespace mio
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#endif // MIO_PAGE_HEADER
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#include <iterator>
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#include <string>
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#include <system_error>
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#include <cstdint>
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#ifdef _WIN32
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# ifndef WIN32_LEAN_AND_MEAN
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# define WIN32_LEAN_AND_MEAN
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# endif // WIN32_LEAN_AND_MEAN
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# include <windows.h>
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#else // ifdef _WIN32
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# define INVALID_HANDLE_VALUE -1
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#endif // ifdef _WIN32
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namespace mio {
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// This value may be provided as the `length` parameter to the constructor or
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// `map`, in which case a memory mapping of the entire file is created.
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enum { map_entire_file = 0 };
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#ifdef _WIN32
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using file_handle_type = HANDLE;
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#else
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using file_handle_type = int;
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#endif
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// This value represents an invalid file handle type. This can be used to
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// determine whether `basic_mmap::file_handle` is valid, for example.
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const static file_handle_type invalid_handle = INVALID_HANDLE_VALUE;
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template<access_mode AccessMode, typename ByteT>
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struct basic_mmap
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{
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using value_type = ByteT;
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using size_type = size_t;
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using reference = value_type&;
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using const_reference = const value_type&;
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using pointer = value_type*;
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using const_pointer = const value_type*;
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using difference_type = std::ptrdiff_t;
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using iterator = pointer;
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using const_iterator = const_pointer;
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using reverse_iterator = std::reverse_iterator<iterator>;
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using const_reverse_iterator = std::reverse_iterator<const_iterator>;
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using iterator_category = std::random_access_iterator_tag;
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using handle_type = file_handle_type;
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static_assert(sizeof(ByteT) == sizeof(char), "ByteT must be the same size as char.");
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private:
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// Points to the first requested byte, and not to the actual start of the mapping.
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pointer data_ = nullptr;
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// Length--in bytes--requested by user (which may not be the length of the
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// full mapping) and the length of the full mapping.
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size_type length_ = 0;
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size_type mapped_length_ = 0;
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// Letting user map a file using both an existing file handle and a path
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// introcudes some complexity (see `is_handle_internal_`).
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// On POSIX, we only need a file handle to create a mapping, while on
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// Windows systems the file handle is necessary to retrieve a file mapping
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// handle, but any subsequent operations on the mapped region must be done
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// through the latter.
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handle_type file_handle_ = INVALID_HANDLE_VALUE;
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#ifdef _WIN32
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handle_type file_mapping_handle_ = INVALID_HANDLE_VALUE;
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#endif
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// Letting user map a file using both an existing file handle and a path
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// introcudes some complexity in that we must not close the file handle if
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// user provided it, but we must close it if we obtained it using the
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// provided path. For this reason, this flag is used to determine when to
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// close `file_handle_`.
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bool is_handle_internal_;
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public:
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/**
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* The default constructed mmap object is in a non-mapped state, that is,
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* any operation that attempts to access nonexistent underlying data will
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* result in undefined behaviour/segmentation faults.
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*/
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basic_mmap() = default;
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#ifdef __cpp_exceptions
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/**
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* The same as invoking the `map` function, except any error that may occur
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* while establishing the mapping is wrapped in a `std::system_error` and is
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* thrown.
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*/
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template<typename String>
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basic_mmap(const String& path, const size_type offset = 0, const size_type length = map_entire_file)
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{
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std::error_code error;
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map(path, offset, length, error);
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if(error) { throw std::system_error(error); }
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}
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/**
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* The same as invoking the `map` function, except any error that may occur
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* while establishing the mapping is wrapped in a `std::system_error` and is
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* thrown.
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*/
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basic_mmap(const handle_type handle, const size_type offset = 0, const size_type length = map_entire_file)
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{
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std::error_code error;
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map(handle, offset, length, error);
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if(error) { throw std::system_error(error); }
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}
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#endif // __cpp_exceptions
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/**
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* `basic_mmap` has single-ownership semantics, so transferring ownership
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* may only be accomplished by moving the object.
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*/
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basic_mmap(const basic_mmap&) = delete;
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basic_mmap(basic_mmap&&);
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basic_mmap& operator=(const basic_mmap&) = delete;
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basic_mmap& operator=(basic_mmap&&);
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/**
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* If this is a read-write mapping, the destructor invokes sync. Regardless
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* of the access mode, unmap is invoked as a final step.
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*/
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~basic_mmap();
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/**
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* On UNIX systems 'file_handle' and 'mapping_handle' are the same. On Windows,
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* however, a mapped region of a file gets its own handle, which is returned by
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* 'mapping_handle'.
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*/
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handle_type file_handle() const noexcept { return file_handle_; }
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handle_type mapping_handle() const noexcept;
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/** Returns whether a valid memory mapping has been created. */
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bool is_open() const noexcept { return file_handle_ != invalid_handle; }
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/**
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* Returns true if no mapping was established, that is, conceptually the
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* same as though the length that was mapped was 0. This function is
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* provided so that this class has Container semantics.
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*/
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bool empty() const noexcept { return length() == 0; }
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/** Returns true if a mapping was established. */
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bool is_mapped() const noexcept;
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/**
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* `size` and `length` both return the logical length, i.e. the number of bytes
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* user requested to be mapped, while `mapped_length` returns the actual number of
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* bytes that were mapped which is a multiple of the underlying operating system's
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* page allocation granularity.
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*/
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size_type size() const noexcept { return length(); }
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size_type length() const noexcept { return length_; }
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size_type mapped_length() const noexcept { return mapped_length_; }
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/** Returns the offset relative to the start of the mapping. */
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size_type mapping_offset() const noexcept
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{
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return mapped_length_ - length_;
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}
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/**
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* Returns a pointer to the first requested byte, or `nullptr` if no memory mapping
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* exists.
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*/
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> pointer data() noexcept { return data_; }
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const_pointer data() const noexcept { return data_; }
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/**
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* Returns an iterator to the first requested byte, if a valid memory mapping
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* exists, otherwise this function call is undefined behaviour.
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*/
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> iterator begin() noexcept { return data(); }
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const_iterator begin() const noexcept { return data(); }
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const_iterator cbegin() const noexcept { return data(); }
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/**
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* Returns an iterator one past the last requested byte, if a valid memory mapping
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* exists, otherwise this function call is undefined behaviour.
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*/
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> iterator end() noexcept { return data() + length(); }
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const_iterator end() const noexcept { return data() + length(); }
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const_iterator cend() const noexcept { return data() + length(); }
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/**
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* Returns a reverse iterator to the last memory mapped byte, if a valid
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* memory mapping exists, otherwise this function call is undefined
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* behaviour.
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*/
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> reverse_iterator rbegin() noexcept { return reverse_iterator(end()); }
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const_reverse_iterator rbegin() const noexcept
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{ return const_reverse_iterator(end()); }
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const_reverse_iterator crbegin() const noexcept
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{ return const_reverse_iterator(end()); }
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/**
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* Returns a reverse iterator past the first mapped byte, if a valid memory
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* mapping exists, otherwise this function call is undefined behaviour.
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*/
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> reverse_iterator rend() noexcept { return reverse_iterator(begin()); }
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const_reverse_iterator rend() const noexcept
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{ return const_reverse_iterator(begin()); }
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const_reverse_iterator crend() const noexcept
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{ return const_reverse_iterator(begin()); }
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/**
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* Returns a reference to the `i`th byte from the first requested byte (as returned
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* by `data`). If this is invoked when no valid memory mapping has been created
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* prior to this call, undefined behaviour ensues.
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*/
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reference operator[](const size_type i) noexcept { return data_[i]; }
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const_reference operator[](const size_type i) const noexcept { return data_[i]; }
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/**
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* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
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* reason is reported via `error` and the object remains in a state as if this
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* function hadn't been called.
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*
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* `path`, which must be a path to an existing file, is used to retrieve a file
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* handle (which is closed when the object destructs or `unmap` is called), which is
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* then used to memory map the requested region. Upon failure, `error` is set to
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* indicate the reason and the object remains in an unmapped state.
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*
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* `offset` is the number of bytes, relative to the start of the file, where the
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* mapping should begin. When specifying it, there is no need to worry about
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* providing a value that is aligned with the operating system's page allocation
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* granularity. This is adjusted by the implementation such that the first requested
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* byte (as returned by `data` or `begin`), so long as `offset` is valid, will be at
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* `offset` from the start of the file.
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*
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* `length` is the number of bytes to map. It may be `map_entire_file`, in which
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* case a mapping of the entire file is created.
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*/
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template<typename String>
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void map(const String& path, const size_type offset,
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const size_type length, std::error_code& error);
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/**
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* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
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* reason is reported via `error` and the object remains in a state as if this
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* function hadn't been called.
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*
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* `path`, which must be a path to an existing file, is used to retrieve a file
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* handle (which is closed when the object destructs or `unmap` is called), which is
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* then used to memory map the requested region. Upon failure, `error` is set to
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* indicate the reason and the object remains in an unmapped state.
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*
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* The entire file is mapped.
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*/
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template<typename String>
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void map(const String& path, std::error_code& error)
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{
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map(path, 0, map_entire_file, error);
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}
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/**
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* Establishes a memory mapping with AccessMode. If the mapping is
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* unsuccesful, the reason is reported via `error` and the object remains in
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* a state as if this function hadn't been called.
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*
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* `handle`, which must be a valid file handle, which is used to memory map the
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* requested region. Upon failure, `error` is set to indicate the reason and the
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* object remains in an unmapped state.
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*
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* `offset` is the number of bytes, relative to the start of the file, where the
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* mapping should begin. When specifying it, there is no need to worry about
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* providing a value that is aligned with the operating system's page allocation
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* granularity. This is adjusted by the implementation such that the first requested
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* byte (as returned by `data` or `begin`), so long as `offset` is valid, will be at
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* `offset` from the start of the file.
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*
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* `length` is the number of bytes to map. It may be `map_entire_file`, in which
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* case a mapping of the entire file is created.
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*/
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void map(const handle_type handle, const size_type offset,
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const size_type length, std::error_code& error);
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/**
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* Establishes a memory mapping with AccessMode. If the mapping is
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* unsuccesful, the reason is reported via `error` and the object remains in
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* a state as if this function hadn't been called.
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*
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* `handle`, which must be a valid file handle, which is used to memory map the
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* requested region. Upon failure, `error` is set to indicate the reason and the
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* object remains in an unmapped state.
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*
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* The entire file is mapped.
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*/
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void map(const handle_type handle, std::error_code& error)
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{
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map(handle, 0, map_entire_file, error);
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}
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/**
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* If a valid memory mapping has been created prior to this call, this call
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* instructs the kernel to unmap the memory region and disassociate this object
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* from the file.
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*
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* The file handle associated with the file that is mapped is only closed if the
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* mapping was created using a file path. If, on the other hand, an existing
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* file handle was used to create the mapping, the file handle is not closed.
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*/
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void unmap();
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void swap(basic_mmap& other);
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/** Flushes the memory mapped page to disk. Errors are reported via `error`. */
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template<access_mode A = AccessMode>
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typename std::enable_if<A == access_mode::write, void>::type
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sync(std::error_code& error);
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/**
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* All operators compare the address of the first byte and size of the two mapped
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* regions.
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*/
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private:
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template<
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access_mode A = AccessMode,
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typename = typename std::enable_if<A == access_mode::write>::type
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> pointer get_mapping_start() noexcept
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{
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return !data() ? nullptr : data() - mapping_offset();
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}
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const_pointer get_mapping_start() const noexcept
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{
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return !data() ? nullptr : data() - mapping_offset();
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}
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/**
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* The destructor syncs changes to disk if `AccessMode` is `write`, but not
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* if it's `read`, but since the destructor cannot be templated, we need to
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* do SFINAE in a dedicated function, where one syncs and the other is a noop.
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*/
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template<access_mode A = AccessMode>
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typename std::enable_if<A == access_mode::write, void>::type
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conditional_sync();
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template<access_mode A = AccessMode>
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typename std::enable_if<A == access_mode::read, void>::type conditional_sync();
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};
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template<access_mode AccessMode, typename ByteT>
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bool operator==(const basic_mmap<AccessMode, ByteT>& a,
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const basic_mmap<AccessMode, ByteT>& b);
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template<access_mode AccessMode, typename ByteT>
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bool operator!=(const basic_mmap<AccessMode, ByteT>& a,
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const basic_mmap<AccessMode, ByteT>& b);
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template<access_mode AccessMode, typename ByteT>
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bool operator<(const basic_mmap<AccessMode, ByteT>& a,
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const basic_mmap<AccessMode, ByteT>& b);
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template<access_mode AccessMode, typename ByteT>
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bool operator<=(const basic_mmap<AccessMode, ByteT>& a,
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const basic_mmap<AccessMode, ByteT>& b);
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template<access_mode AccessMode, typename ByteT>
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bool operator>(const basic_mmap<AccessMode, ByteT>& a,
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const basic_mmap<AccessMode, ByteT>& b);
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template<access_mode AccessMode, typename ByteT>
|
|
bool operator>=(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b);
|
|
|
|
/**
|
|
* This is the basis for all read-only mmap objects and should be preferred over
|
|
* directly using `basic_mmap`.
|
|
*/
|
|
template<typename ByteT>
|
|
using basic_mmap_source = basic_mmap<access_mode::read, ByteT>;
|
|
|
|
/**
|
|
* This is the basis for all read-write mmap objects and should be preferred over
|
|
* directly using `basic_mmap`.
|
|
*/
|
|
template<typename ByteT>
|
|
using basic_mmap_sink = basic_mmap<access_mode::write, ByteT>;
|
|
|
|
/**
|
|
* These aliases cover the most common use cases, both representing a raw byte stream
|
|
* (either with a char or an unsigned char/uint8_t).
|
|
*/
|
|
using mmap_source = basic_mmap_source<char>;
|
|
using ummap_source = basic_mmap_source<unsigned char>;
|
|
|
|
using mmap_sink = basic_mmap_sink<char>;
|
|
using ummap_sink = basic_mmap_sink<unsigned char>;
|
|
|
|
/**
|
|
* Convenience factory method that constructs a mapping for any `basic_mmap` or
|
|
* `basic_mmap` type.
|
|
*/
|
|
template<
|
|
typename MMap,
|
|
typename MappingToken
|
|
> MMap make_mmap(const MappingToken& token,
|
|
int64_t offset, int64_t length, std::error_code& error)
|
|
{
|
|
MMap mmap;
|
|
mmap.map(token, offset, length, error);
|
|
return mmap;
|
|
}
|
|
|
|
/**
|
|
* Convenience factory method.
|
|
*
|
|
* MappingToken may be a String (`std::string`, `std::string_view`, `const char*`,
|
|
* `std::filesystem::path`, `std::vector<char>`, or similar), or a
|
|
* `mmap_source::handle_type`.
|
|
*/
|
|
template<typename MappingToken>
|
|
mmap_source make_mmap_source(const MappingToken& token, mmap_source::size_type offset,
|
|
mmap_source::size_type length, std::error_code& error)
|
|
{
|
|
return make_mmap<mmap_source>(token, offset, length, error);
|
|
}
|
|
|
|
template<typename MappingToken>
|
|
mmap_source make_mmap_source(const MappingToken& token, std::error_code& error)
|
|
{
|
|
return make_mmap_source(token, 0, map_entire_file, error);
|
|
}
|
|
|
|
/**
|
|
* Convenience factory method.
|
|
*
|
|
* MappingToken may be a String (`std::string`, `std::string_view`, `const char*`,
|
|
* `std::filesystem::path`, `std::vector<char>`, or similar), or a
|
|
* `mmap_sink::handle_type`.
|
|
*/
|
|
template<typename MappingToken>
|
|
mmap_sink make_mmap_sink(const MappingToken& token, mmap_sink::size_type offset,
|
|
mmap_sink::size_type length, std::error_code& error)
|
|
{
|
|
return make_mmap<mmap_sink>(token, offset, length, error);
|
|
}
|
|
|
|
template<typename MappingToken>
|
|
mmap_sink make_mmap_sink(const MappingToken& token, std::error_code& error)
|
|
{
|
|
return make_mmap_sink(token, 0, map_entire_file, error);
|
|
}
|
|
|
|
} // namespace mio
|
|
|
|
// #include "detail/mmap.ipp"
|
|
/* Copyright 2017 https://github.com/mandreyel
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
|
|
* software and associated documentation files (the "Software"), to deal in the Software
|
|
* without restriction, including without limitation the rights to use, copy, modify,
|
|
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to the following
|
|
* conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all copies
|
|
* or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
|
|
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
|
|
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
|
|
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
|
|
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
#ifndef MIO_BASIC_MMAP_IMPL
|
|
#define MIO_BASIC_MMAP_IMPL
|
|
|
|
// #include "mio/mmap.hpp"
|
|
|
|
// #include "mio/page.hpp"
|
|
|
|
// #include "mio/detail/string_util.hpp"
|
|
/* Copyright 2017 https://github.com/mandreyel
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
|
|
* software and associated documentation files (the "Software"), to deal in the Software
|
|
* without restriction, including without limitation the rights to use, copy, modify,
|
|
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to the following
|
|
* conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all copies
|
|
* or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
|
|
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
|
|
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
|
|
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
|
|
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
#ifndef MIO_STRING_UTIL_HEADER
|
|
#define MIO_STRING_UTIL_HEADER
|
|
|
|
#include <type_traits>
|
|
|
|
namespace mio {
|
|
namespace detail {
|
|
|
|
template<
|
|
typename S,
|
|
typename C = typename std::decay<S>::type,
|
|
typename = decltype(std::declval<C>().data()),
|
|
typename = typename std::enable_if<
|
|
std::is_same<typename C::value_type, char>::value
|
|
#ifdef _WIN32
|
|
|| std::is_same<typename C::value_type, wchar_t>::value
|
|
#endif
|
|
>::type
|
|
> struct char_type_helper {
|
|
using type = typename C::value_type;
|
|
};
|
|
|
|
template<class T>
|
|
struct char_type {
|
|
using type = typename char_type_helper<T>::type;
|
|
};
|
|
|
|
// TODO: can we avoid this brute force approach?
|
|
template<>
|
|
struct char_type<char*> {
|
|
using type = char;
|
|
};
|
|
|
|
template<>
|
|
struct char_type<const char*> {
|
|
using type = char;
|
|
};
|
|
|
|
template<size_t N>
|
|
struct char_type<char[N]> {
|
|
using type = char;
|
|
};
|
|
|
|
template<size_t N>
|
|
struct char_type<const char[N]> {
|
|
using type = char;
|
|
};
|
|
|
|
#ifdef _WIN32
|
|
template<>
|
|
struct char_type<wchar_t*> {
|
|
using type = wchar_t;
|
|
};
|
|
|
|
template<>
|
|
struct char_type<const wchar_t*> {
|
|
using type = wchar_t;
|
|
};
|
|
|
|
template<size_t N>
|
|
struct char_type<wchar_t[N]> {
|
|
using type = wchar_t;
|
|
};
|
|
|
|
template<size_t N>
|
|
struct char_type<const wchar_t[N]> {
|
|
using type = wchar_t;
|
|
};
|
|
#endif // _WIN32
|
|
|
|
template<typename CharT, typename S>
|
|
struct is_c_str_helper
|
|
{
|
|
static constexpr bool value = std::is_same<
|
|
CharT*,
|
|
// TODO: I'm so sorry for this... Can this be made cleaner?
|
|
typename std::add_pointer<
|
|
typename std::remove_cv<
|
|
typename std::remove_pointer<
|
|
typename std::decay<
|
|
S
|
|
>::type
|
|
>::type
|
|
>::type
|
|
>::type
|
|
>::value;
|
|
};
|
|
|
|
template<typename S>
|
|
struct is_c_str
|
|
{
|
|
static constexpr bool value = is_c_str_helper<char, S>::value;
|
|
};
|
|
|
|
#ifdef _WIN32
|
|
template<typename S>
|
|
struct is_c_wstr
|
|
{
|
|
static constexpr bool value = is_c_str_helper<wchar_t, S>::value;
|
|
};
|
|
#endif // _WIN32
|
|
|
|
template<typename S>
|
|
struct is_c_str_or_c_wstr
|
|
{
|
|
static constexpr bool value = is_c_str<S>::value
|
|
#ifdef _WIN32
|
|
|| is_c_wstr<S>::value
|
|
#endif
|
|
;
|
|
};
|
|
|
|
template<
|
|
typename String,
|
|
typename = decltype(std::declval<String>().data()),
|
|
typename = typename std::enable_if<!is_c_str_or_c_wstr<String>::value>::type
|
|
> const typename char_type<String>::type* c_str(const String& path)
|
|
{
|
|
return path.data();
|
|
}
|
|
|
|
template<
|
|
typename String,
|
|
typename = decltype(std::declval<String>().empty()),
|
|
typename = typename std::enable_if<!is_c_str_or_c_wstr<String>::value>::type
|
|
> bool empty(const String& path)
|
|
{
|
|
return path.empty();
|
|
}
|
|
|
|
template<
|
|
typename String,
|
|
typename = typename std::enable_if<is_c_str_or_c_wstr<String>::value>::type
|
|
> const typename char_type<String>::type* c_str(String path)
|
|
{
|
|
return path;
|
|
}
|
|
|
|
template<
|
|
typename String,
|
|
typename = typename std::enable_if<is_c_str_or_c_wstr<String>::value>::type
|
|
> bool empty(String path)
|
|
{
|
|
return !path || (*path == 0);
|
|
}
|
|
|
|
} // namespace detail
|
|
} // namespace mio
|
|
|
|
#endif // MIO_STRING_UTIL_HEADER
|
|
|
|
|
|
#include <algorithm>
|
|
|
|
#ifndef _WIN32
|
|
# include <unistd.h>
|
|
# include <fcntl.h>
|
|
# include <sys/mman.h>
|
|
# include <sys/stat.h>
|
|
#endif
|
|
|
|
namespace mio {
|
|
namespace detail {
|
|
|
|
#ifdef _WIN32
|
|
namespace win {
|
|
|
|
/** Returns the 4 upper bytes of an 8-byte integer. */
|
|
inline DWORD int64_high(int64_t n) noexcept
|
|
{
|
|
return n >> 32;
|
|
}
|
|
|
|
/** Returns the 4 lower bytes of an 8-byte integer. */
|
|
inline DWORD int64_low(int64_t n) noexcept
|
|
{
|
|
return n & 0xffffffff;
|
|
}
|
|
|
|
std::wstring s_2_ws(const std::string& s)
|
|
{
|
|
if (s.empty())
|
|
return{};
|
|
const auto s_length = static_cast<int>(s.length());
|
|
auto buf = std::vector<wchar_t>(s_length);
|
|
const auto wide_char_count = MultiByteToWideChar(CP_UTF8, 0, s.c_str(), s_length, buf.data(), s_length);
|
|
return std::wstring(buf.data(), wide_char_count);
|
|
}
|
|
|
|
template<
|
|
typename String,
|
|
typename = typename std::enable_if<
|
|
std::is_same<typename char_type<String>::type, char>::value
|
|
>::type
|
|
> file_handle_type open_file_helper(const String& path, const access_mode mode)
|
|
{
|
|
return ::CreateFileW(s_2_ws(path).c_str(),
|
|
mode == access_mode::read ? GENERIC_READ : GENERIC_READ | GENERIC_WRITE,
|
|
FILE_SHARE_READ | FILE_SHARE_WRITE,
|
|
0,
|
|
OPEN_EXISTING,
|
|
FILE_ATTRIBUTE_NORMAL,
|
|
0);
|
|
}
|
|
|
|
template<typename String>
|
|
typename std::enable_if<
|
|
std::is_same<typename char_type<String>::type, wchar_t>::value,
|
|
file_handle_type
|
|
>::type open_file_helper(const String& path, const access_mode mode)
|
|
{
|
|
return ::CreateFileW(c_str(path),
|
|
mode == access_mode::read ? GENERIC_READ : GENERIC_READ | GENERIC_WRITE,
|
|
FILE_SHARE_READ | FILE_SHARE_WRITE,
|
|
0,
|
|
OPEN_EXISTING,
|
|
FILE_ATTRIBUTE_NORMAL,
|
|
0);
|
|
}
|
|
|
|
} // win
|
|
#endif // _WIN32
|
|
|
|
/**
|
|
* Returns the last platform specific system error (errno on POSIX and
|
|
* GetLastError on Win) as a `std::error_code`.
|
|
*/
|
|
inline std::error_code last_error() noexcept
|
|
{
|
|
std::error_code error;
|
|
#ifdef _WIN32
|
|
error.assign(GetLastError(), std::system_category());
|
|
#else
|
|
error.assign(errno, std::system_category());
|
|
#endif
|
|
return error;
|
|
}
|
|
|
|
template<typename String>
|
|
file_handle_type open_file(const String& path, const access_mode mode,
|
|
std::error_code& error)
|
|
{
|
|
error.clear();
|
|
if(detail::empty(path))
|
|
{
|
|
error = std::make_error_code(std::errc::invalid_argument);
|
|
return invalid_handle;
|
|
}
|
|
#ifdef _WIN32
|
|
const auto handle = win::open_file_helper(path, mode);
|
|
#else // POSIX
|
|
const auto handle = ::open(c_str(path),
|
|
mode == access_mode::read ? O_RDONLY : O_RDWR);
|
|
#endif
|
|
if(handle == invalid_handle)
|
|
{
|
|
error = detail::last_error();
|
|
}
|
|
return handle;
|
|
}
|
|
|
|
inline size_t query_file_size(file_handle_type handle, std::error_code& error)
|
|
{
|
|
error.clear();
|
|
#ifdef _WIN32
|
|
LARGE_INTEGER file_size;
|
|
if(::GetFileSizeEx(handle, &file_size) == 0)
|
|
{
|
|
error = detail::last_error();
|
|
return 0;
|
|
}
|
|
return static_cast<int64_t>(file_size.QuadPart);
|
|
#else // POSIX
|
|
struct stat sbuf;
|
|
if(::fstat(handle, &sbuf) == -1)
|
|
{
|
|
error = detail::last_error();
|
|
return 0;
|
|
}
|
|
return sbuf.st_size;
|
|
#endif
|
|
}
|
|
|
|
struct mmap_context
|
|
{
|
|
char* data;
|
|
int64_t length;
|
|
int64_t mapped_length;
|
|
#ifdef _WIN32
|
|
file_handle_type file_mapping_handle;
|
|
#endif
|
|
};
|
|
|
|
inline mmap_context memory_map(const file_handle_type file_handle, const int64_t offset,
|
|
const int64_t length, const access_mode mode, std::error_code& error)
|
|
{
|
|
const int64_t aligned_offset = make_offset_page_aligned(offset);
|
|
const int64_t length_to_map = offset - aligned_offset + length;
|
|
#ifdef _WIN32
|
|
const int64_t max_file_size = offset + length;
|
|
const auto file_mapping_handle = ::CreateFileMapping(
|
|
file_handle,
|
|
0,
|
|
mode == access_mode::read ? PAGE_READONLY : PAGE_READWRITE,
|
|
win::int64_high(max_file_size),
|
|
win::int64_low(max_file_size),
|
|
0);
|
|
if(file_mapping_handle == invalid_handle)
|
|
{
|
|
error = detail::last_error();
|
|
return {};
|
|
}
|
|
char* mapping_start = static_cast<char*>(::MapViewOfFile(
|
|
file_mapping_handle,
|
|
mode == access_mode::read ? FILE_MAP_READ : FILE_MAP_WRITE,
|
|
win::int64_high(aligned_offset),
|
|
win::int64_low(aligned_offset),
|
|
length_to_map));
|
|
if(mapping_start == nullptr)
|
|
{
|
|
// Close file handle if mapping it failed.
|
|
::CloseHandle(file_mapping_handle);
|
|
error = detail::last_error();
|
|
return {};
|
|
}
|
|
#else // POSIX
|
|
char* mapping_start = static_cast<char*>(::mmap(
|
|
0, // Don't give hint as to where to map.
|
|
length_to_map,
|
|
mode == access_mode::read ? PROT_READ : PROT_WRITE,
|
|
MAP_SHARED,
|
|
file_handle,
|
|
aligned_offset));
|
|
if(mapping_start == MAP_FAILED)
|
|
{
|
|
error = detail::last_error();
|
|
return {};
|
|
}
|
|
#endif
|
|
mmap_context ctx;
|
|
ctx.data = mapping_start + offset - aligned_offset;
|
|
ctx.length = length;
|
|
ctx.mapped_length = length_to_map;
|
|
#ifdef _WIN32
|
|
ctx.file_mapping_handle = file_mapping_handle;
|
|
#endif
|
|
return ctx;
|
|
}
|
|
|
|
} // namespace detail
|
|
|
|
// -- basic_mmap --
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
basic_mmap<AccessMode, ByteT>::~basic_mmap()
|
|
{
|
|
conditional_sync();
|
|
unmap();
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
basic_mmap<AccessMode, ByteT>::basic_mmap(basic_mmap&& other)
|
|
: data_(std::move(other.data_))
|
|
, length_(std::move(other.length_))
|
|
, mapped_length_(std::move(other.mapped_length_))
|
|
, file_handle_(std::move(other.file_handle_))
|
|
#ifdef _WIN32
|
|
, file_mapping_handle_(std::move(other.file_mapping_handle_))
|
|
#endif
|
|
, is_handle_internal_(std::move(other.is_handle_internal_))
|
|
{
|
|
other.data_ = nullptr;
|
|
other.length_ = other.mapped_length_ = 0;
|
|
other.file_handle_ = invalid_handle;
|
|
#ifdef _WIN32
|
|
other.file_mapping_handle_ = invalid_handle;
|
|
#endif
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
basic_mmap<AccessMode, ByteT>&
|
|
basic_mmap<AccessMode, ByteT>::operator=(basic_mmap&& other)
|
|
{
|
|
if(this != &other)
|
|
{
|
|
// First the existing mapping needs to be removed.
|
|
unmap();
|
|
data_ = std::move(other.data_);
|
|
length_ = std::move(other.length_);
|
|
mapped_length_ = std::move(other.mapped_length_);
|
|
file_handle_ = std::move(other.file_handle_);
|
|
#ifdef _WIN32
|
|
file_mapping_handle_ = std::move(other.file_mapping_handle_);
|
|
#endif
|
|
is_handle_internal_ = std::move(other.is_handle_internal_);
|
|
|
|
// The moved from basic_mmap's fields need to be reset, because
|
|
// otherwise other's destructor will unmap the same mapping that was
|
|
// just moved into this.
|
|
other.data_ = nullptr;
|
|
other.length_ = other.mapped_length_ = 0;
|
|
other.file_handle_ = invalid_handle;
|
|
#ifdef _WIN32
|
|
other.file_mapping_handle_ = invalid_handle;
|
|
#endif
|
|
other.is_handle_internal_ = false;
|
|
}
|
|
return *this;
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
typename basic_mmap<AccessMode, ByteT>::handle_type
|
|
basic_mmap<AccessMode, ByteT>::mapping_handle() const noexcept
|
|
{
|
|
#ifdef _WIN32
|
|
return file_mapping_handle_;
|
|
#else
|
|
return file_handle_;
|
|
#endif
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
template<typename String>
|
|
void basic_mmap<AccessMode, ByteT>::map(const String& path, const size_type offset,
|
|
const size_type length, std::error_code& error)
|
|
{
|
|
error.clear();
|
|
if(detail::empty(path))
|
|
{
|
|
error = std::make_error_code(std::errc::invalid_argument);
|
|
return;
|
|
}
|
|
const auto handle = detail::open_file(path, AccessMode, error);
|
|
if(error)
|
|
{
|
|
return;
|
|
}
|
|
|
|
map(handle, offset, length, error);
|
|
// This MUST be after the call to map, as that sets this to true.
|
|
if(!error)
|
|
{
|
|
is_handle_internal_ = true;
|
|
}
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
void basic_mmap<AccessMode, ByteT>::map(const handle_type handle,
|
|
const size_type offset, const size_type length, std::error_code& error)
|
|
{
|
|
error.clear();
|
|
if(handle == invalid_handle)
|
|
{
|
|
error = std::make_error_code(std::errc::bad_file_descriptor);
|
|
return;
|
|
}
|
|
|
|
const auto file_size = detail::query_file_size(handle, error);
|
|
if(error)
|
|
{
|
|
return;
|
|
}
|
|
|
|
if(offset + length > file_size)
|
|
{
|
|
error = std::make_error_code(std::errc::invalid_argument);
|
|
return;
|
|
}
|
|
|
|
const auto ctx = detail::memory_map(handle, offset,
|
|
length == map_entire_file ? (file_size - offset) : length,
|
|
AccessMode, error);
|
|
if(!error)
|
|
{
|
|
// We must unmap the previous mapping that may have existed prior to this call.
|
|
// Note that this must only be invoked after a new mapping has been created in
|
|
// order to provide the strong guarantee that, should the new mapping fail, the
|
|
// `map` function leaves this instance in a state as though the function had
|
|
// never been invoked.
|
|
unmap();
|
|
file_handle_ = handle;
|
|
is_handle_internal_ = false;
|
|
data_ = reinterpret_cast<pointer>(ctx.data);
|
|
length_ = ctx.length;
|
|
mapped_length_ = ctx.mapped_length;
|
|
#ifdef _WIN32
|
|
file_mapping_handle_ = ctx.file_mapping_handle;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
template<access_mode A>
|
|
typename std::enable_if<A == access_mode::write, void>::type
|
|
basic_mmap<AccessMode, ByteT>::sync(std::error_code& error)
|
|
{
|
|
error.clear();
|
|
if(!is_open())
|
|
{
|
|
error = std::make_error_code(std::errc::bad_file_descriptor);
|
|
return;
|
|
}
|
|
|
|
if(data())
|
|
{
|
|
#ifdef _WIN32
|
|
if(::FlushViewOfFile(get_mapping_start(), mapped_length_) == 0
|
|
|| ::FlushFileBuffers(file_handle_) == 0)
|
|
#else // POSIX
|
|
if(::msync(get_mapping_start(), mapped_length_, MS_SYNC) != 0)
|
|
#endif
|
|
{
|
|
error = detail::last_error();
|
|
return;
|
|
}
|
|
}
|
|
#ifdef _WIN32
|
|
if(::FlushFileBuffers(file_handle_) == 0)
|
|
{
|
|
error = detail::last_error();
|
|
}
|
|
#endif
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
void basic_mmap<AccessMode, ByteT>::unmap()
|
|
{
|
|
if(!is_open()) { return; }
|
|
// TODO do we care about errors here?
|
|
#ifdef _WIN32
|
|
if(is_mapped())
|
|
{
|
|
::UnmapViewOfFile(get_mapping_start());
|
|
::CloseHandle(file_mapping_handle_);
|
|
}
|
|
#else // POSIX
|
|
if(data_) { ::munmap(const_cast<pointer>(get_mapping_start()), mapped_length_); }
|
|
#endif
|
|
|
|
// If `file_handle_` was obtained by our opening it (when map is called with
|
|
// a path, rather than an existing file handle), we need to close it,
|
|
// otherwise it must not be closed as it may still be used outside this
|
|
// instance.
|
|
if(is_handle_internal_)
|
|
{
|
|
#ifdef _WIN32
|
|
::CloseHandle(file_handle_);
|
|
#else // POSIX
|
|
::close(file_handle_);
|
|
#endif
|
|
}
|
|
|
|
// Reset fields to their default values.
|
|
data_ = nullptr;
|
|
length_ = mapped_length_ = 0;
|
|
file_handle_ = invalid_handle;
|
|
#ifdef _WIN32
|
|
file_mapping_handle_ = invalid_handle;
|
|
#endif
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool basic_mmap<AccessMode, ByteT>::is_mapped() const noexcept
|
|
{
|
|
#ifdef _WIN32
|
|
return file_mapping_handle_ != invalid_handle;
|
|
#else // POSIX
|
|
return is_open();
|
|
#endif
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
void basic_mmap<AccessMode, ByteT>::swap(basic_mmap& other)
|
|
{
|
|
if(this != &other)
|
|
{
|
|
using std::swap;
|
|
swap(data_, other.data_);
|
|
swap(file_handle_, other.file_handle_);
|
|
#ifdef _WIN32
|
|
swap(file_mapping_handle_, other.file_mapping_handle_);
|
|
#endif
|
|
swap(length_, other.length_);
|
|
swap(mapped_length_, other.mapped_length_);
|
|
swap(is_handle_internal_, other.is_handle_internal_);
|
|
}
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
template<access_mode A>
|
|
typename std::enable_if<A == access_mode::write, void>::type
|
|
basic_mmap<AccessMode, ByteT>::conditional_sync()
|
|
{
|
|
// This is invoked from the destructor, so not much we can do about
|
|
// failures here.
|
|
std::error_code ec;
|
|
sync(ec);
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
template<access_mode A>
|
|
typename std::enable_if<A == access_mode::read, void>::type
|
|
basic_mmap<AccessMode, ByteT>::conditional_sync()
|
|
{
|
|
// noop
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator==(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
return a.data() == b.data()
|
|
&& a.size() == b.size();
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator!=(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
return !(a == b);
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator<(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
if(a.data() == b.data()) { return a.size() < b.size(); }
|
|
return a.data() < b.data();
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator<=(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
return !(a > b);
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator>(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
if(a.data() == b.data()) { return a.size() > b.size(); }
|
|
return a.data() > b.data();
|
|
}
|
|
|
|
template<access_mode AccessMode, typename ByteT>
|
|
bool operator>=(const basic_mmap<AccessMode, ByteT>& a,
|
|
const basic_mmap<AccessMode, ByteT>& b)
|
|
{
|
|
return !(a < b);
|
|
}
|
|
|
|
} // namespace mio
|
|
|
|
#endif // MIO_BASIC_MMAP_IMPL
|
|
|
|
|
|
#endif // MIO_MMAP_HEADER
|
|
/* Copyright 2017 https://github.com/mandreyel
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
|
|
* software and associated documentation files (the "Software"), to deal in the Software
|
|
* without restriction, including without limitation the rights to use, copy, modify,
|
|
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to the following
|
|
* conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all copies
|
|
* or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
|
|
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
|
|
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
|
|
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
|
|
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
#ifndef MIO_PAGE_HEADER
|
|
#define MIO_PAGE_HEADER
|
|
|
|
#ifdef _WIN32
|
|
# include <windows.h>
|
|
#else
|
|
# include <unistd.h>
|
|
#endif
|
|
|
|
namespace mio {
|
|
|
|
/**
|
|
* This is used by `basic_mmap` to determine whether to create a read-only or
|
|
* a read-write memory mapping.
|
|
*/
|
|
enum class access_mode
|
|
{
|
|
read,
|
|
write
|
|
};
|
|
|
|
/**
|
|
* Determines the operating system's page allocation granularity.
|
|
*
|
|
* On the first call to this function, it invokes the operating system specific syscall
|
|
* to determine the page size, caches the value, and returns it. Any subsequent call to
|
|
* this function serves the cached value, so no further syscalls are made.
|
|
*/
|
|
inline size_t page_size()
|
|
{
|
|
static const size_t page_size = []
|
|
{
|
|
#ifdef _WIN32
|
|
SYSTEM_INFO SystemInfo;
|
|
GetSystemInfo(&SystemInfo);
|
|
return SystemInfo.dwAllocationGranularity;
|
|
#else
|
|
return sysconf(_SC_PAGE_SIZE);
|
|
#endif
|
|
}();
|
|
return page_size;
|
|
}
|
|
|
|
/**
|
|
* Alligns `offset` to the operating's system page size such that it subtracts the
|
|
* difference until the nearest page boundary before `offset`, or does nothing if
|
|
* `offset` is already page aligned.
|
|
*/
|
|
inline size_t make_offset_page_aligned(size_t offset) noexcept
|
|
{
|
|
const size_t page_size_ = page_size();
|
|
// Use integer division to round down to the nearest page alignment.
|
|
return offset / page_size_ * page_size_;
|
|
}
|
|
|
|
} // namespace mio
|
|
|
|
#endif // MIO_PAGE_HEADER
|
|
/* Copyright 2017 https://github.com/mandreyel
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
|
|
* software and associated documentation files (the "Software"), to deal in the Software
|
|
* without restriction, including without limitation the rights to use, copy, modify,
|
|
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
|
|
* permit persons to whom the Software is furnished to do so, subject to the following
|
|
* conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all copies
|
|
* or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
|
|
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
|
|
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
|
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
|
|
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
|
|
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
*/
|
|
|
|
#ifndef MIO_SHARED_MMAP_HEADER
|
|
#define MIO_SHARED_MMAP_HEADER
|
|
|
|
// #include "mio/mmap.hpp"
|
|
|
|
|
|
#include <system_error> // std::error_code
|
|
#include <memory> // std::shared_ptr
|
|
|
|
namespace mio {
|
|
|
|
/**
|
|
* Exposes (nearly) the same interface as `basic_mmap`, but endowes it with
|
|
* `std::shared_ptr` semantics.
|
|
*
|
|
* This is not the default behaviour of `basic_mmap` to avoid allocating on the heap if
|
|
* shared semantics are not required.
|
|
*/
|
|
template<
|
|
access_mode AccessMode,
|
|
typename ByteT
|
|
> class basic_shared_mmap
|
|
{
|
|
using impl_type = basic_mmap<AccessMode, ByteT>;
|
|
std::shared_ptr<impl_type> pimpl_;
|
|
|
|
public:
|
|
using value_type = typename impl_type::value_type;
|
|
using size_type = typename impl_type::size_type;
|
|
using reference = typename impl_type::reference;
|
|
using const_reference = typename impl_type::const_reference;
|
|
using pointer = typename impl_type::pointer;
|
|
using const_pointer = typename impl_type::const_pointer;
|
|
using difference_type = typename impl_type::difference_type;
|
|
using iterator = typename impl_type::iterator;
|
|
using const_iterator = typename impl_type::const_iterator;
|
|
using reverse_iterator = typename impl_type::reverse_iterator;
|
|
using const_reverse_iterator = typename impl_type::const_reverse_iterator;
|
|
using iterator_category = typename impl_type::iterator_category;
|
|
using handle_type = typename impl_type::handle_type;
|
|
using mmap_type = impl_type;
|
|
|
|
basic_shared_mmap() = default;
|
|
basic_shared_mmap(const basic_shared_mmap&) = default;
|
|
basic_shared_mmap& operator=(const basic_shared_mmap&) = default;
|
|
basic_shared_mmap(basic_shared_mmap&&) = default;
|
|
basic_shared_mmap& operator=(basic_shared_mmap&&) = default;
|
|
|
|
/** Takes ownership of an existing mmap object. */
|
|
basic_shared_mmap(mmap_type&& mmap)
|
|
: pimpl_(std::make_shared<mmap_type>(std::move(mmap)))
|
|
{}
|
|
|
|
/** Takes ownership of an existing mmap object. */
|
|
basic_shared_mmap& operator=(mmap_type&& mmap)
|
|
{
|
|
pimpl_ = std::make_shared<mmap_type>(std::move(mmap));
|
|
return *this;
|
|
}
|
|
|
|
/** Initializes this object with an already established shared mmap. */
|
|
basic_shared_mmap(std::shared_ptr<mmap_type> mmap) : pimpl_(std::move(mmap)) {}
|
|
|
|
/** Initializes this object with an already established shared mmap. */
|
|
basic_shared_mmap& operator=(std::shared_ptr<mmap_type> mmap)
|
|
{
|
|
pimpl_ = std::move(mmap);
|
|
return *this;
|
|
}
|
|
|
|
#ifdef __cpp_exceptions
|
|
/**
|
|
* The same as invoking the `map` function, except any error that may occur
|
|
* while establishing the mapping is wrapped in a `std::system_error` and is
|
|
* thrown.
|
|
*/
|
|
template<typename String>
|
|
basic_shared_mmap(const String& path, const size_type offset = 0, const size_type length = map_entire_file)
|
|
{
|
|
std::error_code error;
|
|
map(path, offset, length, error);
|
|
if(error) { throw std::system_error(error); }
|
|
}
|
|
|
|
/**
|
|
* The same as invoking the `map` function, except any error that may occur
|
|
* while establishing the mapping is wrapped in a `std::system_error` and is
|
|
* thrown.
|
|
*/
|
|
basic_shared_mmap(const handle_type handle, const size_type offset = 0, const size_type length = map_entire_file)
|
|
{
|
|
std::error_code error;
|
|
map(handle, offset, length, error);
|
|
if(error) { throw std::system_error(error); }
|
|
}
|
|
#endif // __cpp_exceptions
|
|
|
|
/**
|
|
* If this is a read-write mapping and the last reference to the mapping,
|
|
* the destructor invokes sync. Regardless of the access mode, unmap is
|
|
* invoked as a final step.
|
|
*/
|
|
~basic_shared_mmap() = default;
|
|
|
|
/** Returns the underlying `std::shared_ptr` instance that holds the mmap. */
|
|
std::shared_ptr<mmap_type> get_shared_ptr() { return pimpl_; }
|
|
|
|
/**
|
|
* On UNIX systems 'file_handle' and 'mapping_handle' are the same. On Windows,
|
|
* however, a mapped region of a file gets its own handle, which is returned by
|
|
* 'mapping_handle'.
|
|
*/
|
|
handle_type file_handle() const noexcept
|
|
{
|
|
return pimpl_ ? pimpl_->file_handle() : invalid_handle;
|
|
}
|
|
|
|
handle_type mapping_handle() const noexcept
|
|
{
|
|
return pimpl_ ? pimpl_->mapping_handle() : invalid_handle;
|
|
}
|
|
|
|
/** Returns whether a valid memory mapping has been created. */
|
|
bool is_open() const noexcept { return pimpl_ && pimpl_->is_open(); }
|
|
|
|
/**
|
|
* Returns true if no mapping was established, that is, conceptually the
|
|
* same as though the length that was mapped was 0. This function is
|
|
* provided so that this class has Container semantics.
|
|
*/
|
|
bool empty() const noexcept { return !pimpl_ || pimpl_->empty(); }
|
|
|
|
/**
|
|
* `size` and `length` both return the logical length, i.e. the number of bytes
|
|
* user requested to be mapped, while `mapped_length` returns the actual number of
|
|
* bytes that were mapped which is a multiple of the underlying operating system's
|
|
* page allocation granularity.
|
|
*/
|
|
size_type size() const noexcept { return pimpl_ ? pimpl_->length() : 0; }
|
|
size_type length() const noexcept { return pimpl_ ? pimpl_->length() : 0; }
|
|
size_type mapped_length() const noexcept
|
|
{
|
|
return pimpl_ ? pimpl_->mapped_length() : 0;
|
|
}
|
|
|
|
/**
|
|
* Returns a pointer to the first requested byte, or `nullptr` if no memory mapping
|
|
* exists.
|
|
*/
|
|
template<
|
|
access_mode A = AccessMode,
|
|
typename = typename std::enable_if<A == access_mode::write>::type
|
|
> pointer data() noexcept { return pimpl_->data(); }
|
|
const_pointer data() const noexcept { return pimpl_ ? pimpl_->data() : nullptr; }
|
|
|
|
/**
|
|
* Returns an iterator to the first requested byte, if a valid memory mapping
|
|
* exists, otherwise this function call is undefined behaviour.
|
|
*/
|
|
iterator begin() noexcept { return pimpl_->begin(); }
|
|
const_iterator begin() const noexcept { return pimpl_->begin(); }
|
|
const_iterator cbegin() const noexcept { return pimpl_->cbegin(); }
|
|
|
|
/**
|
|
* Returns an iterator one past the last requested byte, if a valid memory mapping
|
|
* exists, otherwise this function call is undefined behaviour.
|
|
*/
|
|
template<
|
|
access_mode A = AccessMode,
|
|
typename = typename std::enable_if<A == access_mode::write>::type
|
|
> iterator end() noexcept { return pimpl_->end(); }
|
|
const_iterator end() const noexcept { return pimpl_->end(); }
|
|
const_iterator cend() const noexcept { return pimpl_->cend(); }
|
|
|
|
/**
|
|
* Returns a reverse iterator to the last memory mapped byte, if a valid
|
|
* memory mapping exists, otherwise this function call is undefined
|
|
* behaviour.
|
|
*/
|
|
template<
|
|
access_mode A = AccessMode,
|
|
typename = typename std::enable_if<A == access_mode::write>::type
|
|
> reverse_iterator rbegin() noexcept { return pimpl_->rbegin(); }
|
|
const_reverse_iterator rbegin() const noexcept { return pimpl_->rbegin(); }
|
|
const_reverse_iterator crbegin() const noexcept { return pimpl_->crbegin(); }
|
|
|
|
/**
|
|
* Returns a reverse iterator past the first mapped byte, if a valid memory
|
|
* mapping exists, otherwise this function call is undefined behaviour.
|
|
*/
|
|
template<
|
|
access_mode A = AccessMode,
|
|
typename = typename std::enable_if<A == access_mode::write>::type
|
|
> reverse_iterator rend() noexcept { return pimpl_->rend(); }
|
|
const_reverse_iterator rend() const noexcept { return pimpl_->rend(); }
|
|
const_reverse_iterator crend() const noexcept { return pimpl_->crend(); }
|
|
|
|
/**
|
|
* Returns a reference to the `i`th byte from the first requested byte (as returned
|
|
* by `data`). If this is invoked when no valid memory mapping has been created
|
|
* prior to this call, undefined behaviour ensues.
|
|
*/
|
|
reference operator[](const size_type i) noexcept { return (*pimpl_)[i]; }
|
|
const_reference operator[](const size_type i) const noexcept { return (*pimpl_)[i]; }
|
|
|
|
/**
|
|
* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
|
|
* reason is reported via `error` and the object remains in a state as if this
|
|
* function hadn't been called.
|
|
*
|
|
* `path`, which must be a path to an existing file, is used to retrieve a file
|
|
* handle (which is closed when the object destructs or `unmap` is called), which is
|
|
* then used to memory map the requested region. Upon failure, `error` is set to
|
|
* indicate the reason and the object remains in an unmapped state.
|
|
*
|
|
* `offset` is the number of bytes, relative to the start of the file, where the
|
|
* mapping should begin. When specifying it, there is no need to worry about
|
|
* providing a value that is aligned with the operating system's page allocation
|
|
* granularity. This is adjusted by the implementation such that the first requested
|
|
* byte (as returned by `data` or `begin`), so long as `offset` is valid, will be at
|
|
* `offset` from the start of the file.
|
|
*
|
|
* `length` is the number of bytes to map. It may be `map_entire_file`, in which
|
|
* case a mapping of the entire file is created.
|
|
*/
|
|
template<typename String>
|
|
void map(const String& path, const size_type offset,
|
|
const size_type length, std::error_code& error)
|
|
{
|
|
map_impl(path, offset, length, error);
|
|
}
|
|
|
|
/**
|
|
* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
|
|
* reason is reported via `error` and the object remains in a state as if this
|
|
* function hadn't been called.
|
|
*
|
|
* `path`, which must be a path to an existing file, is used to retrieve a file
|
|
* handle (which is closed when the object destructs or `unmap` is called), which is
|
|
* then used to memory map the requested region. Upon failure, `error` is set to
|
|
* indicate the reason and the object remains in an unmapped state.
|
|
*
|
|
* The entire file is mapped.
|
|
*/
|
|
template<typename String>
|
|
void map(const String& path, std::error_code& error)
|
|
{
|
|
map_impl(path, 0, map_entire_file, error);
|
|
}
|
|
|
|
/**
|
|
* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
|
|
* reason is reported via `error` and the object remains in a state as if this
|
|
* function hadn't been called.
|
|
*
|
|
* `handle`, which must be a valid file handle, which is used to memory map the
|
|
* requested region. Upon failure, `error` is set to indicate the reason and the
|
|
* object remains in an unmapped state.
|
|
*
|
|
* `offset` is the number of bytes, relative to the start of the file, where the
|
|
* mapping should begin. When specifying it, there is no need to worry about
|
|
* providing a value that is aligned with the operating system's page allocation
|
|
* granularity. This is adjusted by the implementation such that the first requested
|
|
* byte (as returned by `data` or `begin`), so long as `offset` is valid, will be at
|
|
* `offset` from the start of the file.
|
|
*
|
|
* `length` is the number of bytes to map. It may be `map_entire_file`, in which
|
|
* case a mapping of the entire file is created.
|
|
*/
|
|
void map(const handle_type handle, const size_type offset,
|
|
const size_type length, std::error_code& error)
|
|
{
|
|
map_impl(handle, offset, length, error);
|
|
}
|
|
|
|
/**
|
|
* Establishes a memory mapping with AccessMode. If the mapping is unsuccesful, the
|
|
* reason is reported via `error` and the object remains in a state as if this
|
|
* function hadn't been called.
|
|
*
|
|
* `handle`, which must be a valid file handle, which is used to memory map the
|
|
* requested region. Upon failure, `error` is set to indicate the reason and the
|
|
* object remains in an unmapped state.
|
|
*
|
|
* The entire file is mapped.
|
|
*/
|
|
void map(const handle_type handle, std::error_code& error)
|
|
{
|
|
map_impl(handle, 0, map_entire_file, error);
|
|
}
|
|
|
|
/**
|
|
* If a valid memory mapping has been created prior to this call, this call
|
|
* instructs the kernel to unmap the memory region and disassociate this object
|
|
* from the file.
|
|
*
|
|
* The file handle associated with the file that is mapped is only closed if the
|
|
* mapping was created using a file path. If, on the other hand, an existing
|
|
* file handle was used to create the mapping, the file handle is not closed.
|
|
*/
|
|
void unmap() { if(pimpl_) pimpl_->unmap(); }
|
|
|
|
void swap(basic_shared_mmap& other) { pimpl_.swap(other.pimpl_); }
|
|
|
|
/** Flushes the memory mapped page to disk. Errors are reported via `error`. */
|
|
template<
|
|
access_mode A = AccessMode,
|
|
typename = typename std::enable_if<A == access_mode::write>::type
|
|
> void sync(std::error_code& error) { if(pimpl_) pimpl_->sync(error); }
|
|
|
|
/** All operators compare the underlying `basic_mmap`'s addresses. */
|
|
|
|
friend bool operator==(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return a.pimpl_ == b.pimpl_;
|
|
}
|
|
|
|
friend bool operator!=(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return !(a == b);
|
|
}
|
|
|
|
friend bool operator<(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return a.pimpl_ < b.pimpl_;
|
|
}
|
|
|
|
friend bool operator<=(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return a.pimpl_ <= b.pimpl_;
|
|
}
|
|
|
|
friend bool operator>(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return a.pimpl_ > b.pimpl_;
|
|
}
|
|
|
|
friend bool operator>=(const basic_shared_mmap& a, const basic_shared_mmap& b)
|
|
{
|
|
return a.pimpl_ >= b.pimpl_;
|
|
}
|
|
|
|
private:
|
|
template<typename MappingToken>
|
|
void map_impl(const MappingToken& token, const size_type offset,
|
|
const size_type length, std::error_code& error)
|
|
{
|
|
if(!pimpl_)
|
|
{
|
|
mmap_type mmap = make_mmap<mmap_type>(token, offset, length, error);
|
|
if(error) { return; }
|
|
pimpl_ = std::make_shared<mmap_type>(std::move(mmap));
|
|
}
|
|
else
|
|
{
|
|
pimpl_->map(token, offset, length, error);
|
|
}
|
|
}
|
|
};
|
|
|
|
/**
|
|
* This is the basis for all read-only mmap objects and should be preferred over
|
|
* directly using basic_shared_mmap.
|
|
*/
|
|
template<typename ByteT>
|
|
using basic_shared_mmap_source = basic_shared_mmap<access_mode::read, ByteT>;
|
|
|
|
/**
|
|
* This is the basis for all read-write mmap objects and should be preferred over
|
|
* directly using basic_shared_mmap.
|
|
*/
|
|
template<typename ByteT>
|
|
using basic_shared_mmap_sink = basic_shared_mmap<access_mode::write, ByteT>;
|
|
|
|
/**
|
|
* These aliases cover the most common use cases, both representing a raw byte stream
|
|
* (either with a char or an unsigned char/uint8_t).
|
|
*/
|
|
using shared_mmap_source = basic_shared_mmap_source<char>;
|
|
using shared_ummap_source = basic_shared_mmap_source<unsigned char>;
|
|
|
|
using shared_mmap_sink = basic_shared_mmap_sink<char>;
|
|
using shared_ummap_sink = basic_shared_mmap_sink<unsigned char>;
|
|
|
|
} // namespace mio
|
|
|
|
#endif // MIO_SHARED_MMAP_HEADER
|