41 lines
999 B
C
41 lines
999 B
C
struct file {
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enum { FD_NONE, FD_PIPE, FD_INODE, FD_DEVICE } type;
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int ref; // reference count
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char readable;
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char writable;
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struct pipe *pipe; // FD_PIPE
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struct inode *ip; // FD_INODE and FD_DEVICE
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uint off; // FD_INODE
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short major; // FD_DEVICE
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};
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#define major(dev) ((dev) >> 16 & 0xFFFF)
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#define minor(dev) ((dev) & 0xFFFF)
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#define mkdev(m,n) ((uint)((m)<<16| (n)))
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// in-memory copy of an inode
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struct inode {
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uint dev; // Device number
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uint inum; // Inode number
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int ref; // Reference count
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struct sleeplock lock; // protects everything below here
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int valid; // inode has been read from disk?
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short type; // copy of disk inode
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short major;
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short minor;
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short nlink;
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uint size;
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uint addrs[NDIRECT+1];
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};
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// map major device number to device functions.
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struct devsw {
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int (*read)(int, uint64, int);
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int (*write)(int, uint64, int);
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};
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extern struct devsw devsw[];
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#define CONSOLE 1
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