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#pragma once
#include "common/types.h"
#include "fs/fs.h"
enum FileType
{
FD_NONE,
FD_INODE,
FD_DEVICE,
FD_PIPE
};
class Pipe;
struct file
{
enum FileType type;
int ref;
char readable;
char writable;
Pipe *pipe; // pipeline pointer
Inode *ip; // VFS Inode
uint32 off; // Current Offset
};
class Pipe
{
public:
static constexpr uint32_t SIZE = 512;
Pipe() : nread(0), nwrite(0), read_open(true), write_open(true)
{
lock.init("pipe");
}
// forbid copy
Pipe(const Pipe &) = delete;
Pipe &operator=(const Pipe &) = delete;
~Pipe()
{
//
}
// creates a pair of connected file objects
static int create_pair(struct file **f0, struct file **f1);
int read(uint64_t addr, int n);
int write(uint64_t addr, int n);
void close(bool is_writer);
private:
Spinlock lock;
char data[SIZE];
uint32_t nread; // read
uint32_t nwrite; // write
bool read_open;
bool write_open;
};
namespace FileTable
{
void init();
struct file *alloc(); // Allocate a free file handle
struct file *dup(struct file *f); // Duplicate handle (sys_dup)
void close(struct file *f); // Close handle
int stat(struct file *f, uint64 addr);
int read(struct file *f, uint64 addr, int n);
int write(struct file *f, uint64 addr, int n);
int lseek(struct file *f, int offset, int whence);
} // namespace FileTable
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