Function SysRecvMsg

Kernel/src/arch/x86_64/syscalls.cpp:1702–1758

* SysRecvMsg (sockfd, msg, flags) - Recieve data through socket * sockfd - Socket file descriptor * msg - Message Header * flags - flags * * On Success - return amount of data received * On Failure - return -1 */

 * On Failure - return -1
 */
long SysRecvMsg(regs64_t* r){
	process_t* proc = Scheduler::GetCurrentProcess();

	if(SC_ARG0(r) >= proc->fileDescriptors.get_length()){
		Log::Warning("sys_sendmsg: Invalid File Descriptor: %d", SC_ARG0(r));
		return -1;
	}

	fs_fd_t* handle = proc->fileDescriptors.get_at(SC_ARG0(r));

	msghdr* msg = (msghdr*)SC_ARG1(r);
	uint64_t flags = SC_ARG3(r);

	if(!handle){ 
		Log::Warning("sys_recvmsg: Invalid file descriptor: ", SC_ARG0(r));
		return -1; 
	}

	if((handle->node->flags & FS_NODE_TYPE) != FS_NODE_SOCKET){
		Log::Warning("sys_recvmsg: File (Descriptor: %d) is not a socket", SC_ARG0(r));
		return -2;
	}
	
	if(!Memory::CheckUsermodePointer(SC_ARG1(r), sizeof(msghdr), proc->addressSpace)){
		Log::Warning("sys_recvmsg: Invalid msg ptr");
		return -EFAULT;
	}
	
	if(!Memory::CheckUsermodePointer((uintptr_t)msg->iov, sizeof(iovec) * msg->iovlen, proc->addressSpace)){
		Log::Warning("sys_recvmsg: msg: Invalid iovec ptr");
		return -EFAULT;
	}

	if(msg->name){
		Log::Warning("sys_recvmsg: msg: name ignored");
	}

	long read = 0;
	Socket* sock = (Socket*)handle->node;

	for(unsigned i = 0; i < msg->iovlen; i++){
		if(!Memory::CheckUsermodePointer((uintptr_t)msg->iov[i].base, msg->iov[i].len, proc->addressSpace)){
			Log::Warning("sys_recvmsg: msg: Invalid iovec entry base");
			return -EFAULT;
		}

		long ret = sock->Receive(msg->iov[i].base, msg->iov[i].len, flags);

		if(ret < 0) {
			return ret;
		}

		read += ret;
	}

	return read;
}