Function SysDup

Kernel/src/arch/x86_64/syscalls.cpp:2016–2033

//////////////////////// \brief SysDup(fd) Duplicate a file descriptor \param fd (int) file descriptor to duplicate \return new file descriptor (int) on success, negative error code on failure ////////////////////////

/// \return new file descriptor (int) on success, negative error code on failure
/////////////////////////////
long SysDup(regs64_t* r){
	int fd = static_cast<int>(SC_ARG0(r));
	fs_fd_t* handle;

	process_t* currentProcess = Scheduler::GetCurrentProcess();
	if(static_cast<unsigned>(fd) >= currentProcess->fileDescriptors.get_length() || !(handle = currentProcess->fileDescriptors[fd])){
		return -EBADF;
	}

	fs_fd_t* newHandle = new fs_fd_t;
	*newHandle = *handle;
	newHandle->node->handleCount++;

	int newFd = currentProcess->fileDescriptors.get_length();
	currentProcess->fileDescriptors.add_back(newHandle);

	return newFd;
}

/////////////////////////////
/// \brief SysGetFileStatusFlags(fd) Get a file handle's mode/status flags