module V1

Return the identifier that was used to construct this device

Connect to the device identified by id

Disconnect from the device. While this might take some time to complete, it can never result in an error.

sleep nsec Block the current thread for TODO remove float

Initialize the generator with a random seed chosen in a system-dependent way.

int bound returns a random integer between 0 (inclusive) and bound (exclusive). bound must be greater than 0 and less than 2³⁰.

int32 bound returns a random integer between 0 (inclusive) and bound (exclusive). bound must be greater than 0.

handler h registers the single global handler that will receive entropy. There might be additional, provider-specific blocking semantics.

Return the current time since 00:00:00 GMT, Jan. 1, 1970, in seconds.

Convert a time in seconds, as returned by time, into a date and a time. Assumes UTC (Coordinated Universal Time), also known as GMT.

read flow will block until it either successfully reads a segment of data from the current flow, receives an Eof signifying that the connection is now closed, or an Error.

write flow buffer will block until buffer has been added to the send queue. There is no indication when the buffer has actually been read and, therefore, it must not be reused. The contents may be transmitted in separate packets, depending on the underlying transport. The result `Ok () indicates success, `Eof indicates that the connection is now closed and `Error indicates some other error.

writev flow buffers will block until the buffers have all been added to the send queue. There is no indication when the buffers have actually been read and, therefore, they must not be reused. The result `Ok () indicates success, `Eof indicates that the connection is now closed and `Error indicates some other error.

close flow will flush all pending writes and signal the end of the flow to the remote endpoint. When the result unit io becomes determined, all further calls to read flow will result in a `Eof.

log str writes as much characters of str that can be written in one write operation to the console t, then writes "\r\n" to it.

log_s str is a thread that writes str ^ "\r\n" in the console t.

Query the characteristics of a specific block device

read device sector_start buffers returns a blocking IO operation which attempts to fill buffers with data starting at sector_start. Each of buffers must be a whole number of sectors in length. The list of buffers can be of any length.

write device sector_start buffers returns a blocking IO operation which attempts to write the data contained within buffers to t starting at sector_start. When the IO operation completes then all writes have been persisted.

Once submitted, it is not possible to cancel a request and there is no timeout.

The operation may fail with `Unimplemented: the operation has not been implemented, no data has been written `Is_read_only: the device is read-only, no data has been written `Disconnected: the device has been disconnected at application request, an unknown amount of data has been written `Unknown: some other permanent, fatal error (e.g. disk is on fire), where an unknown amount of data has been written

Each of buffers must be a whole number of sectors in length. The list of buffers can be of any length.

The data will not be copied, so the supplied buffers must not be re-used until the IO operation completes.

write nf buf outputs buf to netfront nf.

writev nf bufs output a list of buffers to netfront nf as a single packet.

listen nf fn is a blocking operation that calls fn buf with every packet that is read from the interface. It returns as soon as it has initialised, and the function can be stopped by calling disconnect in the device layer.

mac nf is the MAC address of nf.

Obtain the most recent snapshot of the device statistics.

Reset the statistics associated with this device to their defaults.

write nf buf outputs buf to netfront nf.

writev nf bufs output a list of buffers to netfront nf as a single packet.

mac nf is the MAC address of nf.

FIXME listen nf fn is a blocking operation that calls fn buf with every packet that is read from the interface. It returns as soon as it has initialised, and the function can be stopped by calling disconnect in the device layer.

input ~tcp ~udp ~default ip buf demultiplexes an incoming buffer that contains an IP frame. It examines the protocol header and passes the result onto either the tcp or udp function, or the default function for unknown IP protocols.

allocate_frame t ~dst ~proto retrurns a pair (pkt, len) such that Cstruct.sub pkt 0 len is the IP header (including the link layer part) of a packet going to dst for protocol proto. The space in pkt after the first len bytes can be used by the client.

write t frame buf writes the packet frame :: buf :: [] to the address dst.

writev t frame bufs writes the packet frame :: bufs.

checksum frame bufs computes the IP checksum of bufs computing the pseudo-header from the actual header frame. It assumes that frame is of the form returned by allocate_frame, i.e., that it contains the link-layer part.

get_source ip ~dst is the source address to be used to send a packet to dst.

Set the IP address associated with this interface. For IPv4, currently only supports a single IPv4 address, and aliases will be added in a future revision.

Get the IP addresses associated with this interface.

Set an IP netmask associated with this interface. For IPv4, currently only supports a single IPv4 netmask, and aliases will be added in a future revision.

Get the IP netmasks associated with this interface.

Set an IP gateways associated with this interface.

Get the IP gateways associated with this interface.

input listeners t demultiplexes incoming datagrams based on their destination port. The listeners callback is will either return a concrete handler or a None, which results in the datagram being dropped.

write ~source_port ~dest_ip ~dest_port udp data is a thread that writes data from an optional source_port to a dest_ip and dest_port IPv4 address pair.

Get the destination IPv4 address and destination port that a flow is currently connected to.

write_nodelay flow will block until the contents of buffer list are all successfully transmitted to the remote endpoint. Buffering within the stack is minimized in this mode. Note that this API will change in a future revision to be a per-flow attribute instead of a separately exposed function.

writev_nodelay flow will block until the contents of buffer list are all successfully transmitted to the remote endpoint. Buffering within the stack is minimized in this mode. Note that this API will change in a future revision to be a per-flow attribute instead of a separately exposed function.

create_connection t (addr,port) will open a TCPv4 connection to the specified endpoint.

input t listeners defines a mapping of threads that are willing to accept new flows on a given port. If the callback returns None, the input function will return an RST to refuse connections on a port.

udpv4 t obtains a descriptor for use with the UDPV4 module, usually to transmit traffic.

tcpv4 t obtains a descriptor for use with the TCPV4 module, usually to initiate outgoing connections.

ipv4 t obtains a descriptor for use with the IPV4 module, which can handle raw IPv4 frames, or manipulate IP address configuration on the stack interface.

listen_udpv4 t ~port cb will register the cb callback on the UDPv4 port and immediately return. Multiple bindings to the same port will overwrite previous bindings, so callbacks will not chain if ports clash.

listen_tcpv4 t ~port cb will register the cb callback on the TCPv4 port and immediately return. Multiple bindings to the same port will overwrite previous bindings, so callbacks will not chain if ports clash.

listen t will cause the stack to listen for traffic on the network interface associated with the stack, and demultiplex traffic to the appropriate callbacks.

create flow will allocate send and receive buffers and associated them with the given unbuffered flow.

to_flow t will return the flow that backs this channel.

Read a single character from the channel, blocking if there is no immediately available input data.

read_until t ch will read from the channel until the given ch character is found. It returns a tuple indicating whether the character was found at all (false indicates that an EOF condition occurred before the character was encountered), and the buffer pointing to the position immediately after the character (or the complete scanned buffer if the character was never encountered).

read_stream ?len t will return up to len characters as a stream of buffers. This call will probably be removed in a future revision of the API in favour of read_some.

read_line t will read a line of input, which is terminated either by a CRLF sequence, or the end of the channel (which counts as a line).

write_char t ch writes a single character to the output channel.

write_string t buf off len writes len bytes from a string buf, starting from from offset off.

write_buffer t buf will copy the buffer to the channel's output buffer. The buffer should not be modified after being written, and it will be recycled into the buffer allocation pool at some future point.

write_line t buf will write the string buf to the output channel and append a newline character afterwards.

flush t will flush the output buffer and block if necessary until it is all written out to the flow.

close t will call flush and then close the underlying flow.

read t key offset length reads up to length bytes from the value associated with key. If less data is returned than requested, this indicates the end of the value.

Get the value size.

format t size erases the contents of t and creates an empty filesystem of size size bytes

create t path creates an empty file at path

mkdir t path creates an empty directory at path

destroy t path removes a path (which may be a file or an empty directory) on filesystem t

stat t path returns information about file or directory at path

listdir t path returns the names of files and subdirectories within the directory path

write t path offset data writes data at offset in file path on filesystem t

get n allocates and returns a memory block of n pages. If there is not enough memory, the unikernel will terminate.

get_order i is get (1 lsl i).

pages n allocates a memory block of n pages and return the the list of pages allocated.

pages_order i is pages (1 lsl i).

length t is the size of t, in bytes.

to_pages t is a list of size memory blocks of one page each, where size is the size of t in pages.

string_blit src srcoff dst dstoff len copies len bytes from string src, starting at byte number srcoff, to memory block dst, starting at byte number dstoff.

blit t1 t2 is the same as Bigarray.Array1.blit.

round_to_page_size n returns the number of bytes that will be allocated for storing n bytes in memory

read t key offset length reads up to length bytes from the value associated with key. If less data is returned than requested, this indicates the end of the value.

Get the value size.