Libuv Internal Architecture

Libuv

its a cross -plateform async IO libery . its c++ small libery

Features:

• event loop
• TCP/UDP sockets
• file system operations
• threading utilities

Libuv Architecture

• Event Loop : uv_loop_t - single threaded event loop
• handles : uv_handles_t - handler is resouces .its a entity that is able to do certain type of works .
• timers handler:- call a callback a certtain amount of time
• tcp handles : handle your connections . reading and writing over the connections
• Requests: uv_req_t : request are operations(standalone and with handler both ) , uv write a write some data over a string connections , fs open : request for open a file(standalone operation)

other utilities

three main block

Os Dependent

1. network IO
2. File IO
3. other stuff

Os Independent Block

1. os independent stuff

Os Independent Block

• uv_TCP_t
• uv_PIPE_t
• uv_TTY_t
• uv_UDP_t
• uv_POLL_t
• uv_IOT_t
• uv_stream_t
• Operating System

Network IO

uv_TCP_t , PIPE , TTY , UDP , POLL > handle low level IO
TCP pipes , tty : stream based > stream of data -> tcp.c -> less code even string.c have full code of how handle tcp
uv IOT -> in unix (linuc.court.c)
in mac > darwin.c

The I/O loop

The input and output is the central part of libuv Arc. It implemented the code for all I/O operations, and it’s basically tied to a single thread. if run multiple of event loops then each runs in a different thread. The libuv event loop is not thread-safe The event loop uses usually single threaded asynchronous approach event loop will block waiting for Input and output activity on sockets As part of a loop iteration the loop :

File IO

for uv fs requests

uv_work_t,uv_fs_t,uv_getaddr_info,uv_get_name_info,thread pool
uv_work_t : user supplied funtion to do custom works
uv_getaddr_info,uv_get_name_info : DNS request : like name resolutions

all these run on the thread pool
thread pool : build with our os independently utility
we use thread only for
thread fileio
getAddrinfo
default size is 4

Others

os_independent
uv_timer_t , idle , prepain , check
os_dependent
uv_singnal_t
uv_process_t

libuv : event_loop

LIBUV CODE FOR EVENT LOOP