61 lines
1009 B
C++
61 lines
1009 B
C++
#include <unistd.h>
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#include <sys/mman.h>
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#include <cerrno>
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class MappedFile
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{
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public:
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MappedFile(int fd, bool readOnly)
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{
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_fd = fd;
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_length = ::lseek(fd, 0, SEEK_END);
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_address = MAP_FAILED;
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if (_length > 0)
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{
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_address = ::mmap(0, _length,
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readOnly ? PROT_READ : PROT_READ | PROT_WRITE,
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MAP_FILE, fd, 0);
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}
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}
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MappedFile(void *address, size_t size)
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{
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_fd = -1;
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_address = address;
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_size = size;
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}
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~MappedFile()
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{
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if (_address != MAP_FAILED) ::munmap(_address, _length);
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if (_fd != -1) ::close(_fd);
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}
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void *address() const
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{
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return _address;
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}
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size_t length()
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{
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return _length;
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}
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int sync()
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{
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if (::msync(_address, _length, MS_SYNC) == 0)
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return 0;
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return errno;
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}
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private:
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int _fd;
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void *_address;
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size_t _length;
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}; |