git-svn-id: https://profuse.googlecode.com/svn/branches/v2@200 aa027e90-d47c-11dd-86d7-074df07e0730

MappedFile.cpp

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