Files
agila_open_tool/tools/v/vlib/fasthttp/fasthttp_linux.v
T

886 lines
30 KiB
V

module fasthttp
import net
import sync.stdatomic
import time
#include <sys/epoll.h>
#include <sys/sendfile.h>
#include <sys/stat.h>
#include <netinet/tcp.h>
const epoll_wait_timeout_ms = 100
const status_408_response = 'HTTP/1.1 408 Request Timeout\r\nContent-Type: text/plain\r\nContent-Length: 19\r\nConnection: close\r\n\r\n408 Request Timeout'.bytes()
fn C.accept4(sockfd i32, addr &net.Addr, addrlen &u32, flags i32) i32
fn C.epoll_create1(__flags i32) i32
fn C.epoll_ctl(__epfd i32, __op i32, __fd i32, __event &C.epoll_event) i32
fn C.epoll_wait(__epfd i32, __events &C.epoll_event, __maxevents i32, __timeout i32) i32
fn C.sendfile(out_fd i32, in_fd i32, offset &i64, count usize) i32
fn C.fstat(fd i32, buf &C.stat) i32
@[typedef]
union C.epoll_data_t {
mut:
ptr voidptr
fd int
u32 u32
u64 u64
}
struct C.epoll_event {
mut:
events u32
data C.epoll_data_t
}
pub struct Server {
pub:
family net.AddrFamily = .ip6
port int = 3000
max_request_buffer_size int = 8192
timeout_in_seconds int = 30
user_data voidptr
mut:
listen_fds []int = []int{len: max_thread_pool_size, cap: max_thread_pool_size, init: -1}
epoll_fds []int = []int{len: max_thread_pool_size, cap: max_thread_pool_size, init: -1}
threads []thread = []thread{len: max_thread_pool_size, cap: max_thread_pool_size}
request_handler fn (HttpRequest) !HttpResponse @[required]
running &stdatomic.AtomicVal[bool] = stdatomic.new_atomic(false)
shutting_down &stdatomic.AtomicVal[bool] = stdatomic.new_atomic(false)
stopped &stdatomic.AtomicVal[bool] = stdatomic.new_atomic(true)
active_requests &stdatomic.AtomicVal[int] = stdatomic.new_atomic(0)
}
// new_server creates and initializes a new Server instance.
pub fn new_server(config ServerConfig) !&Server {
if config.max_request_buffer_size <= 0 {
return error('max_request_buffer_size must be greater than 0')
}
mut server := &Server{
family: config.family
port: config.port
max_request_buffer_size: config.max_request_buffer_size
timeout_in_seconds: config.timeout_in_seconds
user_data: config.user_data
request_handler: config.handler
running: stdatomic.new_atomic(false)
shutting_down: stdatomic.new_atomic(false)
stopped: stdatomic.new_atomic(true)
active_requests: stdatomic.new_atomic(0)
}
unsafe {
server.listen_fds.flags.set(.noslices | .noshrink | .nogrow)
server.epoll_fds.flags.set(.noslices | .noshrink | .nogrow)
server.threads.flags.set(.noslices | .noshrink | .nogrow)
}
return server
}
fn set_blocking(fd int, blocking bool) {
flags := C.fcntl(fd, C.F_GETFL, 0)
if flags == -1 {
// TODO: better error handling
eprintln(@LOCATION)
return
}
if blocking {
// This removes the O_NONBLOCK flag from flags and set it.
C.fcntl(fd, C.F_SETFL, flags & ~C.O_NONBLOCK)
} else {
// This adds the O_NONBLOCK flag from flags and set it.
C.fcntl(fd, C.F_SETFL, flags | C.O_NONBLOCK)
}
}
// ClientWriteState carries the pending response bytes plus optional file data
// for a connection that could not be drained in a single non-blocking write.
// It lives in `client_write_states` until both the in-memory content and the
// file body have been fully transferred. While a state exists, the connection
// is also armed for EPOLLOUT so process_events can resume the write without
// blocking the worker.
struct ClientWriteState {
mut:
content []u8
content_pos int
content_owned bool
file_fd int = -1
file_len i64
file_pos i64
should_close bool
request_arena voidptr
request_active bool
start_ns i64
// epollout_armed records whether we actually had to register EPOLLOUT for
// this connection. When set, complete_write performs a DEL+ADD on the fd to
// re-deliver any pipelined request bytes that arrived during the write as a
// fresh EPOLLIN edge (level-triggered semantics are not used here).
epollout_armed bool
}
// drain_status describes the outcome of one try_drain_write() pass.
enum DrainStatus {
done // all bytes (content + file) have been sent
blocked // the kernel send buffer is full; come back on EPOLLOUT
failed // unrecoverable error or peer closed mid-transfer
}
fn close_socket(fd int) bool {
ret := C.close(fd)
if ret == -1 {
if C.errno == C.EINTR {
// Interrupted by signal, retry is safe
return close_socket(fd)
}
eprintln('ERROR: close(fd=${fd}) failed with errno=${C.errno}')
return false
}
return true
}
fn create_server_socket(server Server) int {
// Create a socket with non-blocking mode
server_fd := C.socket(i32(server.family), i32(net.SocketType.tcp), 0)
if server_fd < 0 {
eprintln(@LOCATION)
C.perror(c'Socket creation failed')
return -1
}
set_blocking(server_fd, false)
// Enable SO_REUSEADDR and SO_REUSEPORT
opt := 1
if C.setsockopt(server_fd, C.SOL_SOCKET, C.SO_REUSEADDR, &opt, sizeof(opt)) < 0 {
eprintln(@LOCATION)
C.perror(c'setsockopt SO_REUSEADDR failed')
close_socket(server_fd)
return -1
}
if C.setsockopt(server_fd, C.SOL_SOCKET, C.SO_REUSEPORT, &opt, sizeof(opt)) < 0 {
eprintln(@LOCATION)
C.perror(c'setsockopt SO_REUSEPORT failed')
close_socket(server_fd)
return -1
}
addr := if server.family == .ip6 {
net.new_ip6(u16(server.port), [u8(0), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]!)
} else {
net.new_ip(u16(server.port), [u8(0), 0, 0, 0]!)
}
alen := addr.len()
if C.bind(server_fd, voidptr(&addr), alen) < 0 {
eprintln(@LOCATION)
C.perror(c'Bind failed')
close_socket(server_fd)
return -1
}
if C.listen(server_fd, max_connection_size) < 0 {
eprintln(@LOCATION)
C.perror(c'Listen failed')
close_socket(server_fd)
return -1
}
return server_fd
}
// add_fd_to_epoll adds a file descriptor to the epoll instance
fn add_fd_to_epoll(epoll_fd int, fd int, events u32) int {
mut ev := C.epoll_event{
events: events
}
ev.data.fd = fd
if C.epoll_ctl(epoll_fd, C.EPOLL_CTL_ADD, fd, &ev) == -1 {
eprintln(@LOCATION)
C.perror(c'epoll_ctl')
return -1
}
return 0
}
// remove_fd_from_epoll removes a file descriptor from the epoll instance
fn remove_fd_from_epoll(epoll_fd int, fd int) bool {
ret := C.epoll_ctl(epoll_fd, C.EPOLL_CTL_DEL, fd, C.NULL)
if ret == -1 {
eprintln('ERROR: epoll_ctl(DEL, fd=${fd}) failed with errno=${C.errno}')
return false
}
return true
}
fn handle_accept_loop(epoll_fd int, listen_fd int, mut client_fds map[int]bool) {
for {
client_fd := C.accept4(listen_fd, C.NULL, C.NULL, C.SOCK_NONBLOCK)
if client_fd < 0 {
if C.errno == C.EAGAIN || C.errno == C.EWOULDBLOCK {
break // No more incoming connections; exit loop.
}
eprintln(@LOCATION)
C.perror(c'Accept failed')
break
}
// Enable TCP_NODELAY for lower latency
opt := 1
C.setsockopt(client_fd, C.IPPROTO_TCP, C.TCP_NODELAY, &opt, sizeof(opt))
// Register client socket with epoll
if add_fd_to_epoll(epoll_fd, client_fd, u32(C.EPOLLIN | C.EPOLLET)) == -1 {
close_socket(client_fd)
continue
}
client_fds[client_fd] = true
}
}
fn free_write_state(server &Server, client_fd int, mut client_write_states map[int]&ClientWriteState) {
mut state := client_write_states[client_fd] or { return }
if state.content_owned && state.content.cap > 0 {
unsafe { state.content.free() }
}
state.content = []u8{}
if state.file_fd != -1 {
C.close(state.file_fd)
state.file_fd = -1
}
$if prealloc {
if state.request_arena != unsafe { nil } {
unsafe { prealloc_scope_free_after(state.request_arena) }
}
}
state.request_arena = unsafe { nil }
if state.request_active {
server.end_request()
state.request_active = false
}
client_write_states.delete(client_fd)
unsafe { free(state) }
}
fn handle_client_closure(server &Server, epoll_fd int, client_fd int, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
// Never close the listening socket here
if client_fd == 0 {
return
}
if client_fd <= 0 {
eprintln('ERROR: Invalid FD=${client_fd} for closure')
return
}
client_fds.delete(client_fd)
client_buffers.delete(client_fd)
client_read_starts.delete(client_fd)
closing_client_fds.delete(client_fd)
free_write_state(server, client_fd, mut client_write_states)
remove_fd_from_epoll(epoll_fd, client_fd)
close_socket(client_fd)
}
fn close_worker_clients(server &Server, epoll_fd int, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
for client_fd in client_fds.keys() {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
}
fn drain_closing_client(server &Server, epoll_fd int, client_fd int, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
mut drain_buf := []u8{len: 4096}
for {
bytes_read := C.recv(client_fd, unsafe { &drain_buf[0] }, drain_buf.len, 0)
if bytes_read < 0 {
if C.errno == C.EAGAIN || C.errno == C.EWOULDBLOCK {
return
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
if bytes_read == 0 {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
}
}
fn send_terminal_response_and_drain(client_fd int, response []u8, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool) {
C.send(client_fd, response.data, response.len, C.MSG_NOSIGNAL)
net.shutdown(client_fd, how: .write)
client_buffers.delete(client_fd)
client_read_starts.delete(client_fd)
closing_client_fds[client_fd] = true
}
// try_drain_write attempts to push the remaining bytes of `state.content` and
// (if present) `state.file_fd` to the socket in non-blocking mode. It returns
// `.done` once all data has been transferred, `.blocked` when the kernel send
// buffer is full (EAGAIN/EWOULDBLOCK), or `.failed` on any unrecoverable error.
// The caller is responsible for parking the state until EPOLLOUT fires (when
// `.blocked` is returned) and for cleaning up via `free_write_state` once
// `.done` or `.failed` is reached.
fn try_drain_write(client_fd int, mut state ClientWriteState) DrainStatus {
// 1. Drain in-memory content (response headers + possibly a body).
for state.content_pos < state.content.len {
remaining := state.content.len - state.content_pos
sent := C.send(client_fd, unsafe { &state.content[state.content_pos] }, remaining,
C.MSG_NOSIGNAL)
if sent > 0 {
state.content_pos += sent
continue
}
if sent < 0 {
errno_val := C.errno
if errno_val == C.EAGAIN || errno_val == C.EWOULDBLOCK {
return .blocked
}
if errno_val == C.EINTR {
continue
}
eprintln('ERROR: send() failed with errno=${errno_val}')
return .failed
}
// send() returning 0 on a non-blocking TCP socket is unusual; treat it as
// a failure rather than spin.
return .failed
}
// 2. Drain the optional file body via sendfile(2). sendfile updates the
// offset pointer in place, so `state.file_pos` advances automatically.
if state.file_fd != -1 {
for state.file_pos < state.file_len {
remaining := state.file_len - state.file_pos
ssize := C.sendfile(client_fd, state.file_fd, &state.file_pos, usize(remaining))
if ssize > 0 {
continue
}
if ssize == 0 {
// Short transfer: the file shrank between fstat() and now, or the
// peer closed. We have already promised the full Content-Length,
// so the response is now truncated -- closing the connection is
// the only way to keep keep-alive clients in sync.
eprintln('ERROR: sendfile() returned 0 with ${remaining} bytes still pending; closing connection to avoid desync')
return .failed
}
errno_val := C.errno
if errno_val == C.EAGAIN || errno_val == C.EWOULDBLOCK {
return .blocked
}
if errno_val == C.EINTR {
continue
}
match errno_val {
C.EBADF {
eprintln('ERROR: sendfile() EBADF: input fd or socket not open for required access (errno=${errno_val})')
}
C.EFAULT {
eprintln('ERROR: sendfile() EFAULT: bad address for offset (errno=${errno_val})')
}
C.EINVAL {
eprintln('ERROR: sendfile() EINVAL: invalid descriptor state or non-seekable input (errno=${errno_val})')
}
C.EIO {
eprintln('ERROR: sendfile() EIO: I/O error while reading input file (errno=${errno_val})')
}
C.ENOMEM {
eprintln('ERROR: sendfile() ENOMEM: insufficient kernel memory (errno=${errno_val})')
}
C.EOVERFLOW {
eprintln('ERROR: sendfile() EOVERFLOW: count exceeds file/socket limits (errno=${errno_val})')
}
C.ESPIPE {
eprintln('ERROR: sendfile() ESPIPE: input file not seekable with offset (errno=${errno_val})')
}
else {
eprintln('ERROR: sendfile() failed with errno=${errno_val}')
}
}
return .failed
}
// Done with the file -- close the fd eagerly so keep-alive doesn't hold it open.
C.close(state.file_fd)
state.file_fd = -1
}
return .done
}
// arm_epollout switches the connection's epoll mask from EPOLLIN|EPOLLET to
// EPOLLIN|EPOLLOUT|EPOLLET so the next round of pending bytes is delivered as
// an EPOLLOUT event instead of blocking the worker.
fn arm_epollout(epoll_fd int, client_fd int) int {
mut ev := C.epoll_event{
events: u32(C.EPOLLIN | C.EPOLLOUT | C.EPOLLET)
}
ev.data.fd = client_fd
return C.epoll_ctl(epoll_fd, C.EPOLL_CTL_MOD, client_fd, &ev)
}
// complete_write tears down the per-fd write state after a successful drain,
// then either closes the connection or leaves it in keep-alive mode.
fn complete_write(server &Server, epoll_fd int, client_fd int, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
state := client_write_states[client_fd] or { return }
should_close := state.should_close
epollout_was_armed := state.epollout_armed
free_write_state(server, client_fd, mut client_write_states)
client_buffers.delete(client_fd)
if server.is_shutting_down() || should_close {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
// Keep-alive: if EPOLLOUT was registered for the write, drop the fd from
// epoll and re-add it with the original EPOLLIN|EPOLLET mask. The re-add
// causes the kernel to fire a fresh edge for any pipelined request bytes
// that piled up in the recv buffer while we were write-blocked; a plain
// EPOLL_CTL_MOD would not generate that edge.
if epollout_was_armed {
remove_fd_from_epoll(epoll_fd, client_fd)
if add_fd_to_epoll(epoll_fd, client_fd, u32(C.EPOLLIN | C.EPOLLET)) == -1 {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
}
}
// handle_write resumes a blocked write when EPOLLOUT fires for `client_fd`.
fn handle_write(server &Server, epoll_fd int, client_fd int, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
mut state := client_write_states[client_fd] or { return }
status := try_drain_write(client_fd, mut state)
match status {
.done {
complete_write(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
.blocked {
// Still blocked -- stay armed for the next EPOLLOUT.
}
.failed {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
}
}
fn process_request(server &Server, epoll_fd int, client_fd int, request_buffer []u8, mut client_fds map[int]bool, mut client_buffers map[int][]u8, mut client_read_starts map[int]i64, mut closing_client_fds map[int]bool, mut client_write_states map[int]&ClientWriteState) {
mut request_arena := voidptr(unsafe { nil })
$if prealloc {
request_arena = unsafe { prealloc_scope_begin() }
}
client_read_starts.delete(client_fd)
server.begin_request()
mut request_active := true
mut decoded_http_request := decode_http_request(request_buffer) or {
eprintln('Error decoding request ${err}')
C.send(client_fd, tiny_bad_request_response.data, tiny_bad_request_response.len,
C.MSG_NOSIGNAL)
end_request_arena_current_thread(request_arena)
if request_active {
server.end_request()
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
$if trace_prealloc ? {
unsafe { prealloc_scope_checkpoint(c'fasthttp decoded request') }
}
decoded_http_request.client_conn_fd = client_fd
decoded_http_request.user_data = server.user_data
mut response := server.request_handler(decoded_http_request) or {
eprintln('Error handling request ${err}')
C.send(client_fd, tiny_bad_request_response.data, tiny_bad_request_response.len,
C.MSG_NOSIGNAL)
end_request_arena_current_thread(request_arena)
if request_active {
server.end_request()
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
$if trace_prealloc ? {
unsafe { prealloc_scope_checkpoint(c'fasthttp handler returned') }
}
response.attach_request_arena_if_empty(request_arena)
match response.takeover_mode {
.manual {
// The handler has taken ownership of the connection.
// Remove from epoll and tracking, but do NOT close the fd.
client_fds.delete(client_fd)
client_buffers.delete(client_fd)
client_read_starts.delete(client_fd)
closing_client_fds.delete(client_fd)
remove_fd_from_epoll(epoll_fd, client_fd)
response.abandon_request_arena_current_thread()
response.free_owned_content()
if request_active {
server.end_request()
}
return
}
.reusable {
set_blocking(client_fd, false)
client_buffers.delete(client_fd)
response.free_owned_content()
response.end_request_arena_current_thread()
if request_active {
server.end_request()
}
if server.is_shutting_down() || response.should_close {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
}
return
}
.none {}
}
// Open the file (if any) before constructing the state so we can fail fast
// while we still own the request arena via response.
mut file_fd := -1
mut file_len := i64(0)
if response.file_path != '' {
fd := C.open(response.file_path.str, C.O_RDONLY, 0)
if fd == -1 {
eprintln('ERROR: open file failed')
response.free_owned_content()
response.end_request_arena_current_thread()
if request_active {
server.end_request()
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
mut st := C.stat{}
if C.fstat(fd, &st) != 0 {
eprintln('ERROR: fstat failed')
C.close(fd)
response.free_owned_content()
response.end_request_arena_current_thread()
if request_active {
server.end_request()
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
file_fd = fd
file_len = i64(st.st_size)
}
// Move content + arena ownership into the per-fd state. After this point we
// must not touch the response's arena via end/free (it will be released by
// free_write_state once the drain completes).
content_bytes := response.take_or_clone_content()
arena_ptr := response.take_request_arena()
leave_request_arena_current_thread(arena_ptr)
mut state := &ClientWriteState{
content: content_bytes
content_pos: 0
content_owned: true
file_fd: file_fd
file_len: file_len
file_pos: 0
should_close: response.should_close
request_arena: arena_ptr
request_active: request_active
start_ns: time.sys_mono_now()
}
// From here on, the state owns end_request bookkeeping.
request_active = false
client_write_states[client_fd] = state
status := try_drain_write(client_fd, mut state)
match status {
.done {
complete_write(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
.blocked {
// Kernel send buffer is full. Park the state and resume on EPOLLOUT.
client_buffers.delete(client_fd)
client_read_starts.delete(client_fd)
if arm_epollout(epoll_fd, client_fd) == -1 {
eprintln('ERROR: epoll_ctl(MOD, EPOLLOUT) failed errno=${C.errno}')
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
} else {
state.epollout_armed = true
}
}
.failed {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
}
}
}
fn process_events(server &Server, epoll_fd int, listen_fd int) {
mut events := [max_connection_size]C.epoll_event{}
mut request_buffer := []u8{len: server.max_request_buffer_size, cap: server.max_request_buffer_size}
mut client_fds := map[int]bool{}
mut client_buffers := map[int][]u8{}
mut client_read_starts := map[int]i64{}
mut closing_client_fds := map[int]bool{}
mut client_write_states := map[int]&ClientWriteState{}
unsafe {
request_buffer.flags.set(.noslices | .nogrow | .noshrink)
}
for {
if server.is_shutting_down() && server.active_request_count() == 0 {
close_worker_clients(server, epoll_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
return
}
num_events := C.epoll_wait(epoll_fd, &events[0], max_connection_size, epoll_wait_timeout_ms)
if num_events < 0 {
if C.errno == C.EINTR {
continue
}
if server.is_shutting_down() {
continue
}
eprintln('ERROR: epoll_wait() failed with errno=${C.errno}')
continue
}
for i := 0; i < num_events; i++ {
client_fd := unsafe { events[i].data.fd }
// Accept new connections when the listening socket is readable
if client_fd == listen_fd {
if server.is_shutting_down() {
continue
}
handle_accept_loop(epoll_fd, listen_fd, mut client_fds)
continue
}
if events[i].events & u32((C.EPOLLHUP | C.EPOLLERR)) != 0 {
if client_fd == listen_fd {
eprintln('ERROR: listen fd had HUP/ERR')
continue
}
if client_fd > 0 {
// Don't bother sending 444 if there is an in-flight write -- the
// peer is already disconnected and we want to tear down promptly.
if client_fd !in client_write_states {
C.send(client_fd, status_444_response.data, status_444_response.len,
C.MSG_NOSIGNAL)
}
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
} else {
eprintln('ERROR: Invalid FD from epoll: ${client_fd}')
}
continue
}
if events[i].events & u32(C.EPOLLOUT) != 0 {
handle_write(server, epoll_fd, client_fd, mut client_fds, mut client_buffers, mut
client_read_starts, mut closing_client_fds, mut client_write_states)
// If both EPOLLIN and EPOLLOUT fired, we still want to drain the
// socket -- fall through to the EPOLLIN branch below.
if client_fd !in client_fds {
continue
}
}
if events[i].events & u32(C.EPOLLIN) != 0 {
if server.is_shutting_down() {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
continue
}
if closing_client_fds[client_fd] or { false } {
drain_closing_client(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
continue
}
if client_fd in client_write_states {
// A response is still being drained for this fd. Reading a new
// request now would overwrite the in-flight ClientWriteState and
// silently drop the response/file transfer. Defer until the write
// completes -- on keep-alive completion we re-arm EPOLLIN below so
// any bytes that arrived during the write get delivered as a fresh
// edge.
continue
}
// Read all available data from the socket
mut total_bytes_read := 0
mut readed_request_buffer := client_buffers[client_fd] or {
[]u8{cap: server.max_request_buffer_size}
}
mut headers_complete := false
mut header_too_large := false
mut header_end_pos := -1
mut request_complete := false
mut peer_closed := false
mut recv_error := false
for {
bytes_read := C.recv(client_fd, unsafe { &request_buffer[0] },
server.max_request_buffer_size - 1, 0)
if bytes_read < 0 {
if C.errno == C.EAGAIN || C.errno == C.EWOULDBLOCK {
// No more data available right now
break
}
// Error occurred
eprintln('ERROR: recv() failed with errno=${C.errno}')
recv_error = true
break
} else if bytes_read == 0 {
// Connection closed by client
peer_closed = true
break
}
unsafe {
readed_request_buffer.push_many(&request_buffer[0], bytes_read)
}
total_bytes_read += bytes_read
if client_fd !in client_read_starts {
client_read_starts[client_fd] = time.sys_mono_now()
}
// Enforce the configured limit on request headers, not on the whole body.
buffer_len := readed_request_buffer.len
if !headers_complete && buffer_len >= 4 {
header_end_pos = find_header_end_in_buf(readed_request_buffer.data,
buffer_len)
if header_end_pos == -1 {
if buffer_len >= server.max_request_buffer_size {
header_too_large = true
break
}
} else {
headers_complete = true
if header_end_pos > server.max_request_buffer_size {
header_too_large = true
break
}
}
}
if headers_complete && has_complete_body(readed_request_buffer.data, buffer_len) {
request_complete = true
break
}
}
if header_too_large {
send_terminal_response_and_drain(client_fd, status_413_response, mut
client_buffers, mut client_read_starts, mut closing_client_fds)
continue
}
if request_complete {
process_request(server, epoll_fd, client_fd, readed_request_buffer, mut
client_fds, mut client_buffers, mut client_read_starts, mut
closing_client_fds, mut client_write_states)
} else if recv_error {
// Unexpected recv error - send 444 No Response
C.send(client_fd, status_444_response.data, status_444_response.len,
C.MSG_NOSIGNAL)
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
} else if peer_closed || (total_bytes_read == 0 && readed_request_buffer.len == 0) {
// Normal client closure (FIN received)
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
} else if readed_request_buffer.len > 0 {
client_buffers[client_fd] = readed_request_buffer
}
}
}
if server.timeout_in_seconds > 0 {
now := time.sys_mono_now()
timeout_ns := i64(server.timeout_in_seconds) * 1_000_000_000
for client_fd in client_read_starts.keys() {
started := client_read_starts[client_fd] or { continue }
if now - started >= timeout_ns {
send_terminal_response_and_drain(client_fd, status_408_response, mut
client_buffers, mut client_read_starts, mut closing_client_fds)
}
}
// Sweep write-side stalls: a client that armed EPOLLOUT but never
// drains within `timeout_in_seconds` gets the connection torn down so
// the worker isn't pinned waiting for a dead peer.
for client_fd in client_write_states.keys() {
state := client_write_states[client_fd] or { continue }
if state.start_ns > 0 && now - state.start_ns >= timeout_ns {
handle_client_closure(server, epoll_fd, client_fd, mut client_fds, mut
client_buffers, mut client_read_starts, mut closing_client_fds, mut
client_write_states)
}
}
}
}
}
fn (mut server Server) stop_accepting() {
for i := 0; i < max_thread_pool_size; i++ {
if server.listen_fds[i] < 0 {
continue
}
if server.epoll_fds[i] >= 0 {
remove_fd_from_epoll(server.epoll_fds[i], server.listen_fds[i])
}
close_socket(server.listen_fds[i])
server.listen_fds[i] = -1
}
}
// run starts the server and begins listening for incoming connections.
pub fn (mut server Server) run() ! {
$if windows {
eprintln('Windows is not supported yet')
return
}
for i := 0; i < max_thread_pool_size; i++ {
server.listen_fds[i] = create_server_socket(server)
if server.listen_fds[i] < 0 {
return
}
server.epoll_fds[i] = C.epoll_create1(0)
if server.epoll_fds[i] < 0 {
C.perror(c'epoll_create1 failed')
close_socket(server.listen_fds[i])
return
}
// Register the listening socket with each worker epoll for distributed accepts (edge-triggered)
if add_fd_to_epoll(server.epoll_fds[i], server.listen_fds[i], u32(C.EPOLLIN | C.EPOLLET)) == -1 {
close_socket(server.listen_fds[i])
close_socket(server.epoll_fds[i])
return
}
server.threads[i] = spawn process_events(server, server.epoll_fds[i], server.listen_fds[i])
}
server.mark_running()
println('listening on http://0.0.0.0:${server.port}/')
// Main thread waits for workers; accepts are handled in worker epoll loops
for i in 0 .. max_thread_pool_size {
server.threads[i].wait()
if server.epoll_fds[i] >= 0 {
close_socket(server.epoll_fds[i])
server.epoll_fds[i] = -1
}
}
server.mark_stopped()
}