29 lines
700 B
C++
29 lines
700 B
C++
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#include "Log.h"
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#include "fs/VFS.h"
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#include "memory/MemoryManager.h"
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#include "sys/Syscall.h"
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#include "thread/Scheduler.h"
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Result<u64> sys_read(Registers*, SyscallArgs args)
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{
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int fd = (int)args[0];
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u8* buf = (u8*)args[1];
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usize size = (usize)args[2];
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if (!MemoryManager::validate_user_write(buf, size)) return err(EFAULT);
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if (fd < 0 || fd >= FD_MAX) return err(EBADF);
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Thread* current = Scheduler::current();
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Option<FileDescriptor>& descriptor = current->fd_table->fds[fd];
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if (!descriptor.has_value()) return err(EBADF);
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usize nread = TRY(descriptor->inode->read(buf, descriptor->offset, size));
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descriptor->offset += nread;
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return nread;
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}
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