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Async working with connection handlers

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This commit is contained in:
Lorenz Stechauner
2022-12-29 01:49:00 +01:00
parent dfc659dec0
commit b90ed61e03
15 changed files with 505 additions and 50 deletions
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18
Makefile
View File

@@ -7,7 +7,7 @@ DEBIAN_OPTS=-D CACHE_MAGIC_FILE="\"/usr/share/file/magic.mgc\"" -D PHP_FPM_SOCKE
.PHONY: all prod debug default debian permit clean test
all: prod
default: bin bin/lib bin/sesimos
default: bin bin/lib bin/worker bin/sesimos
prod: CFLAGS += -O3
prod: default
@@ -29,6 +29,8 @@ bin:
bin/lib:
mkdir -p bin/lib
bin/worker:
mkdir -p bin/worker
bin/test: test/mock_*.c test/test_*.c src/lib/utils.c src/lib/sock.c
$(CC) -o $@ $(CFLAGS) $^ -lcriterion
@@ -40,10 +42,14 @@ bin/%.o: src/%.c
bin/lib/%.o: src/lib/%.c
$(CC) -c -o $@ $(CFLAGS) $<
bin/worker/%.o: src/worker/%.c
$(CC) -c -o $@ $(CFLAGS) $<
bin/sesimos: bin/server.o bin/client.o bin/logger.o bin/cache_handler.o bin/async.o \
bin/worker/request_handler.o bin/worker/tcp_acceptor.o bin/worker/tcp_closer.o \
bin/lib/compress.o bin/lib/config.o bin/lib/fastcgi.o bin/lib/geoip.o \
bin/lib/http.o bin/lib/http_static.o bin/lib/proxy.o bin/lib/sock.o bin/lib/uri.o \
bin/lib/utils.o bin/lib/websocket.o
bin/lib/utils.o bin/lib/websocket.o bin/lib/mpmc.o
$(CC) -o $@ $^ $(CFLAGS) $(LDFLAGS)
@@ -60,6 +66,12 @@ bin/cache_handler.o: src/cache_handler.h src/lib/utils.h src/lib/uri.h src/lib/c
bin/async.o: src/async.h src/logger.h
bin/worker/request_handler.o: src/worker/request_handler.h
bin/worker/tcp_acceptor.o: src/worker/tcp_acceptor.h
bin/worker/tcp_closer.o: src/worker/tcp_closer.h
bin/lib/compress.o: src/lib/compress.h
bin/lib/config.o: src/lib/config.h src/lib/utils.h src/lib/uri.h src/logger.h
@@ -71,6 +83,8 @@ bin/lib/geoip.o: src/lib/geoip.h
bin/lib/http.o: src/lib/http.h src/lib/utils.h src/lib/compress.h src/lib/sock.h src/logger.h
bin/lib/mpmc.o: src/lib/mpmc.h src/logger.h
bin/lib/proxy.o: src/lib/proxy.h src/defs.h src/server.h src/lib/compress.h src/logger.h
bin/lib/sock.o: src/lib/sock.h

10
src/async.c
View File

@@ -13,6 +13,7 @@
#include <signal.h>
#include <errno.h>
#include <memory.h>
#include <pthread.h>
typedef struct {
int fd;
@@ -31,10 +32,12 @@ typedef struct {
static listen_queue_t listen1, listen2, *listen = &listen1;
static volatile sig_atomic_t alive = 1;
static pthread_t thread = -1;
static int async_add_to_queue(evt_listen_t *evt) {
// TODO locking
memcpy(&listen->q[listen->n++], evt, sizeof(*evt));
if (thread != -1) pthread_kill(thread, SIGUSR1);
return 0;
}
@@ -55,6 +58,8 @@ void async_thread(void) {
int num_fds;
struct pollfd fds[256]; // TODO dynamic
thread = pthread_self();
// main event loop
while (alive) {
// swap listen queue
@@ -70,6 +75,7 @@ void async_thread(void) {
if (poll(fds, num_fds, -1) < 0) {
if (errno == EINTR) {
// interrupt
errno = 0;
} else {
// other error
critical("Unable to poll for events");
@@ -101,3 +107,7 @@ void async_thread(void) {
l->n = 0;
}
}
void async_stop(void) {
alive = 0;
}

4
src/async.h
View File

@@ -9,10 +9,14 @@
#ifndef SESIMOS_ASYNC_H
#define SESIMOS_ASYNC_H
#include <poll.h>
#define ASYNC_KEEP 1
int async(int fd, short events, int flags, void cb(void *), void *arg, void err_cb(void *), void *err_arg);
void async_thread(void);
void async_stop(void);
#endif //SESIMOS_ASYNC_H

8
src/cache_handler.c
View File

@@ -203,7 +203,7 @@ static void cache_process_entry(cache_entry_t *entry) {
static void *cache_thread(void *arg) {
logger_set_name("cache");
while (alive) {
while (server_alive) {
pthread_testcancel();
if (sem_wait(&sem_used) != 0) {
if (errno == EINTR) {
@@ -257,10 +257,14 @@ int cache_init(void) {
}
close(fd);
errno = 0;
}
// try to initialize all three semaphores
if (sem_init(&sem_lock, 0, 1) != 0|| sem_init(&sem_free, 0, 1) != 0 || sem_init(&sem_used, 0, 0) != 0) {
if (sem_init(&sem_lock, 0, 1) != 0 ||
sem_init(&sem_free, 0, 1) != 0 ||
sem_init(&sem_used, 0, 0) != 0)
{
critical("Unable to initialize semaphore");
return -1;
}

15
src/client.h
View File

@@ -16,14 +16,13 @@
typedef struct {
sock socket;
char *addr;
char *s_addr;
unsigned char s_keep_alive:1;
unsigned char c_keep_alive:1;
char cc[3];
char host[256];
char _c_addr[INET6_ADDRSTRLEN + 1];
char _s_addr[INET6_ADDRSTRLEN + 1];
int req_num;
char *addr, *s_addr;
unsigned char in_use: 1, s_keep_alive:1, c_keep_alive:1;
char cc[3], host[256];
char log_prefix[512];
char _c_addr[INET6_ADDRSTRLEN + 1], _s_addr[INET6_ADDRSTRLEN + 1];
struct timespec begin, end;
} client_ctx_t;
host_config_t *get_host_config(const char *host);

158
src/lib/mpmc.c Normal file
View File

@@ -0,0 +1,158 @@
#include "mpmc.h"
#include "../logger.h"
#include <errno.h>
#include <malloc.h>
#include <memory.h>
#include <pthread.h>
#include <signal.h>
static void *mpmc_worker(void *arg);
int mpmc_init(mpmc_t *ctx, int n_workers, int buf_size, void (*consumer)(void *obj), const char *prefix) {
ctx->alive = 1;
ctx->n_workers = n_workers;
ctx->size = buf_size, ctx->max_size = buf_size;
ctx->rd = 0, ctx->wr = 0;
ctx->buffer = NULL, ctx->workers = NULL;
ctx->consumer = consumer;
if (sem_init(&ctx->free, 0, ctx->size) != 0 ||
sem_init(&ctx->used, 0, 0) != 0 ||
sem_init(&ctx->lck_rd, 0, 1) != 0 ||
sem_init(&ctx->lck_wr, 0, 1) != 0)
{
mpmc_destroy(ctx);
return -1;
}
if ((ctx->buffer = malloc(ctx->size * sizeof(void *))) == NULL ||
(ctx->workers = malloc(ctx->n_workers * sizeof(pthread_t))) == NULL)
{
mpmc_destroy(ctx);
return -1;
}
memset(ctx->buffer, 0, ctx->size * sizeof(void *));
memset(ctx->workers, 0, ctx->n_workers * sizeof(pthread_t));
for (int i = 0; i < ctx->n_workers; i++) {
int ret;
if ((ret = pthread_create(&ctx->workers[i], NULL, mpmc_worker, ctx)) != 0) {
mpmc_destroy(ctx);
errno = ret;
return -1;
}
}
return 0;
}
int mpmc_queue(mpmc_t *ctx, void *obj) {
// wait for buffer to be emptied
try_again_1:
if (sem_wait(&ctx->free) != 0) {
if (errno == EINTR) {
goto try_again_1;
} else {
return -1;
}
}
// lock rd field
try_again_2:
if (sem_wait(&ctx->lck_rd) != 0) {
if (errno == EINTR) {
goto try_again_2;
} else {
sem_post(&ctx->free);
return -1;
}
}
int p = ctx->rd;
ctx->rd = (ctx->rd + 1) % ctx->size;
// unlock rd field
sem_post(&ctx->lck_rd);
// fill buffer with object
ctx->buffer[p] = obj;
// inform worker
sem_post(&ctx->used);
return 0;
}
static void *mpmc_worker(void *arg) {
mpmc_t *ctx = arg;
while (ctx->alive) {
// wait for buffer to be filled
if (sem_wait(&ctx->used) != 0) {
if (errno == EINTR) {
continue;
} else {
critical("Unable to lock semaphore");
break;
}
}
// lock wr field
if (sem_wait(&ctx->lck_wr) != 0) {
if (errno == EINTR) {
sem_post(&ctx->used);
continue;
} else {
critical("Unable to lock semaphore");
sem_post(&ctx->used);
break;
}
}
int p = ctx->wr;
ctx->wr = (ctx->wr + 1) % ctx->size;
// unlock wr field
sem_post(&ctx->lck_wr);
// consume object
ctx->consumer(ctx->buffer[p]);
logger_set_prefix("");
// unlock slot in buffer
sem_post(&ctx->free);
}
return NULL;
}
void mpmc_stop(mpmc_t *ctx) {
ctx->alive = 0;
}
void mpmc_destroy(mpmc_t *ctx) {
int e = errno;
// stop threads, if running
mpmc_stop(ctx);
for (int i = 0; i < ctx->n_workers; i++) {
if (ctx->workers[i] == 0) break;
// FIXME
pthread_kill(ctx->workers[i], SIGUSR1);
//pthread_join(ctx->workers[i], NULL);
pthread_cancel(ctx->workers[i]);
}
sem_destroy(&ctx->free);
sem_destroy(&ctx->used);
sem_destroy(&ctx->lck_rd);
sem_destroy(&ctx->lck_wr);
free(ctx->buffer);
free(ctx->workers);
// reset errno
errno = e;
}

26
src/lib/mpmc.h Normal file
View File

@@ -0,0 +1,26 @@
#ifndef SESIMOS_MPMC_H
#define SESIMOS_MPMC_H
#include <semaphore.h>
typedef struct {
unsigned char alive;
int n_workers;
int rd, wr;
sem_t free, used, lck_rd, lck_wr;
int size, max_size;
void **buffer;
pthread_t *workers;
void (*consumer)(void *obj);
} mpmc_t;
int mpmc_init(mpmc_t *ctx, int n_workers, int buf_size, void (*consumer)(void *obj), const char *prefix);
int mpmc_queue(mpmc_t *ctx, void *obj);
void mpmc_stop(mpmc_t *ctx);
void mpmc_destroy(mpmc_t *ctx);
#endif //SESIMOS_MPMC_H

66
src/server.c
View File

@@ -11,11 +11,14 @@
#include "client.h"
#include "logger.h"
#include "async.h"
#include "worker/tcp_acceptor.h"
#include "cache_handler.h"
#include "lib/config.h"
#include "lib/proxy.h"
#include "lib/geoip.h"
#include "worker/tcp_closer.h"
#include "worker/request_handler.h"
#include <stdio.h>
#include <getopt.h>
@@ -33,11 +36,10 @@
#include <openssl/conf.h>
volatile sig_atomic_t alive = 1;
volatile sig_atomic_t server_alive = 1;
const char *config_file;
static int sockets[NUM_SOCKETS];
static pthread_t children[MAX_CHILDREN];
static SSL_CTX *contexts[CONFIG_MAX_CERT_CONFIG];
static client_ctx_t clients[MAX_CLIENTS]; // TODO dynamic
@@ -62,10 +64,11 @@ static void accept_cb(void *arg) {
int fd = sockets[i];
int j;
for (j = 0; j < MAX_CHILDREN; j++) {
if (children[j] == 0) break;
for (j = 0; j < MAX_CLIENTS; j++) {
if (clients[j].in_use == 0) break;
}
client_ctx_t *client_ctx = &clients[j];
client_ctx->in_use = 1;
sock *client = &client_ctx->socket;
client->ctx = contexts[0];
@@ -78,11 +81,8 @@ static void accept_cb(void *arg) {
client->socket = client_fd;
client->enc = (i == 1);
pthread_t ret = pthread_create(&children[j], NULL, (void *(*)(void *)) &client_handler, client);
if (ret != 0) {
errno = (int) ret;
critical("Unable to create thread");
}
tcp_accept(client_ctx);
}
static void accept_err_cb(void *arg) {
@@ -95,18 +95,9 @@ static void terminate_forcefully(int sig) {
fprintf(stderr, "\n");
notice("Terminating forcefully!");
int ret;
for (int i = 0; i < MAX_CHILDREN; i++) {
if (children[i] != 0) {
if ((ret = pthread_kill(children[i], SIGKILL)) < 0) {
errno = ret;
error("Unable to wait for child process (PID %i)", children[i]);
errno = 0;
}
}
}
geoip_free();
notice("Goodbye");
exit(2);
}
@@ -114,38 +105,37 @@ static void terminate_gracefully(int sig) {
fprintf(stderr, "\n");
notice("Terminating gracefully...");
alive = 0;
server_alive = 0;
signal(SIGINT, terminate_forcefully);
signal(SIGTERM, terminate_forcefully);
tcp_acceptor_stop();
request_handler_stop();
tcp_closer_stop();
tcp_acceptor_destroy();
request_handler_destroy();
tcp_closer_destroy();
for (int i = 0; i < NUM_SOCKETS; i++) {
shutdown(sockets[i], SHUT_RDWR);
close(sockets[i]);
}
int ret;
for (int i = 0; i < MAX_CHILDREN; i++) {
if (children[i] != 0) {
ret = pthread_kill(children[i], SIGKILL);
if (ret < 0) {
critical("Unable to wait for child process (PID %i)", children[i]);
} else if (ret == children[i]) {
children[i] = 0;
}
}
}
info("Goodbye");
notice("Goodbye");
geoip_free();
exit(0);
}
static void nothing(int sig) {}
int main(int argc, char *const argv[]) {
const int YES = 1;
int ret;
memset(sockets, 0, sizeof(sockets));
memset(children, 0, sizeof(children));
memset(clients, 0, sizeof(clients));
const struct sockaddr_in6 addresses[2] = {
{.sin6_family = AF_INET6, .sin6_addr = IN6ADDR_ANY_INIT, .sin6_port = htons(80)},
@@ -221,6 +211,7 @@ int main(int argc, char *const argv[]) {
signal(SIGINT, terminate_gracefully);
signal(SIGTERM, terminate_gracefully);
signal(SIGUSR1, nothing);
if ((ret = geoip_init(config.geoip_dir)) != 0) {
if (ret == -1) {
@@ -271,11 +262,14 @@ int main(int argc, char *const argv[]) {
}
}
tcp_acceptor_init(CNX_HANDLER_WORKERS, 64);
tcp_closer_init(CNX_HANDLER_WORKERS, 64);
request_handler_init(REQ_HANDLER_WORKERS, 64);
for (int i = 0; i < NUM_SOCKETS; i++) {
async(sockets[i], POLLIN, ASYNC_KEEP, accept_cb, &sockets[i], accept_err_cb, &sockets[i]);
}
errno = 0;
notice("Ready to accept connections");
async_thread();

3
src/server.h
View File

@@ -14,7 +14,6 @@
#include <signal.h>
#define NUM_SOCKETS 2
#define MAX_CHILDREN 64
#define LISTEN_BACKLOG 16
#define REQ_PER_CONNECTION 200
#define CLIENT_TIMEOUT 3600
@@ -25,6 +24,6 @@
#define CNX_HANDLER_WORKERS 8
#define REQ_HANDLER_WORKERS 16
extern volatile sig_atomic_t alive;
extern volatile sig_atomic_t server_alive;
#endif //SESIMOS_SERVER_H

31
src/worker/request_handler.c Normal file
View File

@@ -0,0 +1,31 @@
#include "request_handler.h"
#include "../logger.h"
#include "../lib/mpmc.h"
#include "../lib/utils.h"
#include "tcp_closer.h"
static mpmc_t mpmc_ctx;
static void request_handler_func(client_ctx_t *ctx);
int request_handler_init(int n_workers, int buf_size) {
return mpmc_init(&mpmc_ctx, n_workers, buf_size, (void (*)(void *)) request_handler_func, "req");
}
int handle_request(client_ctx_t *ctx) {
return mpmc_queue(&mpmc_ctx, ctx);
}
void request_handler_stop(void) {
mpmc_stop(&mpmc_ctx);
}
void request_handler_destroy(void) {
mpmc_destroy(&mpmc_ctx);
}
static void request_handler_func(client_ctx_t *ctx) {
// TODO
tcp_close(ctx);
}

15
src/worker/request_handler.h Normal file
View File

@@ -0,0 +1,15 @@
#ifndef SESIMOS_REQUEST_HANDLER_H
#define SESIMOS_REQUEST_HANDLER_H
#include "../client.h"
int request_handler_init(int n_workers, int buf_size);
int handle_request(client_ctx_t *ctx);
void request_handler_stop(void);
void request_handler_destroy(void);
#endif //SESIMOS_REQUEST_HANDLER_H

131
src/worker/tcp_acceptor.c Normal file
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@@ -0,0 +1,131 @@
#include "tcp_acceptor.h"
#include "../logger.h"
#include "../lib/mpmc.h"
#include "../lib/utils.h"
#include "../server.h"
#include "../lib/geoip.h"
#include "../async.h"
#include "tcp_closer.h"
#include "request_handler.h"
#include <string.h>
#include <errno.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
static mpmc_t mpmc_ctx;
static void tcp_acceptor_func(client_ctx_t *ctx);
int tcp_acceptor_init(int n_workers, int buf_size) {
return mpmc_init(&mpmc_ctx, n_workers, buf_size, (void (*)(void *)) tcp_acceptor_func, "tcp/a");
}
int tcp_accept(client_ctx_t *ctx) {
return mpmc_queue(&mpmc_ctx, ctx);
}
void tcp_acceptor_stop(void) {
mpmc_stop(&mpmc_ctx);
}
void tcp_acceptor_destroy(void) {
mpmc_destroy(&mpmc_ctx);
}
static void tcp_acceptor_func(client_ctx_t *ctx) {
struct sockaddr_in6 server_addr;
char log_client_prefix[256];
inet_ntop(ctx->socket.addr.ipv6.sin6_family, &ctx->socket.addr.ipv6.sin6_addr, ctx->_c_addr, sizeof(ctx->_c_addr));
if (strncmp(ctx->_c_addr, "::ffff:", 7) == 0) {
ctx->addr = ctx->_c_addr + 7;
} else {
ctx->addr = ctx->_c_addr;
}
socklen_t len = sizeof(server_addr);
getsockname(ctx->socket.socket, (struct sockaddr *) &server_addr, &len);
inet_ntop(server_addr.sin6_family, (void *) &server_addr.sin6_addr, ctx->_s_addr, sizeof(ctx->_s_addr));
if (strncmp(ctx->_s_addr, "::ffff:", 7) == 0) {
ctx->s_addr = ctx->_s_addr + 7;
} else {
ctx->s_addr = ctx->_s_addr;
}
sprintf(log_client_prefix, "[%s%4i%s]%s[%*s][%5i]%s", (int) ctx->socket.enc ? HTTPS_STR : HTTP_STR,
ntohs(server_addr.sin6_port), CLR_STR, /*color_table[0]*/ "", INET6_ADDRSTRLEN, ctx->addr,
ntohs(ctx->socket.addr.ipv6.sin6_port), CLR_STR);
sprintf(ctx->log_prefix, "[%*s]%s", INET6_ADDRSTRLEN, ctx->s_addr, log_client_prefix);
logger_set_prefix(ctx->log_prefix);
int ret;
char buf[1024];
sock *client = &ctx->socket;
clock_gettime(CLOCK_MONOTONIC, &ctx->begin);
if (config.dns_server[0] != 0) {
sprintf(buf, "dig @%s +short +time=1 -x %s", config.dns_server, ctx->addr);
FILE *dig = popen(buf, "r");
if (dig == NULL) {
error("Unable to start dig: %s", strerror(errno));
goto dig_err;
}
unsigned long read = fread(buf, 1, sizeof(buf), dig);
ret = pclose(dig);
if (ret != 0) {
error("Dig terminated with exit code %i", ret);
goto dig_err;
}
char *ptr = memchr(buf, '\n', read);
if (ptr == buf || ptr == NULL) {
goto dig_err;
}
ptr[-1] = 0;
strncpy(ctx->host, buf, sizeof(ctx->host));
} else {
dig_err:
ctx->host[0] = 0;
}
ctx->cc[0] = 0;
geoip_lookup_country(&client->addr.sock, ctx->cc);
info("Connection accepted from %s %s%s%s[%s]", ctx->addr, ctx->host[0] != 0 ? "(" : "",
ctx->host[0] != 0 ? ctx->host : "", ctx->host[0] != 0 ? ") " : "",
ctx->cc[0] != 0 ? ctx->cc : "N/A");
struct timeval client_timeout = {.tv_sec = CLIENT_TIMEOUT, .tv_usec = 0};
if (setsockopt(client->socket, SOL_SOCKET, SO_RCVTIMEO, &client_timeout, sizeof(client_timeout)) == -1 ||
setsockopt(client->socket, SOL_SOCKET, SO_SNDTIMEO, &client_timeout, sizeof(client_timeout)) == -1)
{
error("Unable to set timeout for socket");
tcp_close(ctx);
return;
}
if (client->enc) {
client->ssl = SSL_new(client->ctx);
SSL_set_fd(client->ssl, client->socket);
SSL_set_accept_state(client->ssl);
ret = SSL_accept(client->ssl);
client->_last_ret = ret;
client->_errno = errno;
client->_ssl_error = ERR_get_error();
if (ret <= 0) {
error("Unable to perform handshake: %s", sock_strerror(client));
tcp_close(ctx);
return;
}
}
ctx->req_num = 0;
ctx->s_keep_alive = 1;
ctx->c_keep_alive = 1;
async(ctx->socket.socket, POLLIN, 0, (void (*)(void *)) handle_request, ctx, (void (*)(void *)) tcp_close, ctx);
}

15
src/worker/tcp_acceptor.h Normal file
View File

@@ -0,0 +1,15 @@
#ifndef SESIMOS_TCP_ACCEPTOR_H
#define SESIMOS_TCP_ACCEPTOR_H
#include "../client.h"
int tcp_acceptor_init(int n_workers, int buf_size);
int tcp_accept(client_ctx_t *ctx);
void tcp_acceptor_stop(void);
void tcp_acceptor_destroy(void);
#endif //SESIMOS_TCP_ACCEPTOR_H

40
src/worker/tcp_closer.c Normal file
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@@ -0,0 +1,40 @@
#include "tcp_closer.h"
#include "../logger.h"
#include "../lib/mpmc.h"
#include "../lib/utils.h"
#include <memory.h>
static mpmc_t mpmc_ctx;
static void tcp_closer_func(client_ctx_t *ctx);
int tcp_closer_init(int n_workers, int buf_size) {
return mpmc_init(&mpmc_ctx, n_workers, buf_size, (void (*)(void *)) tcp_closer_func, "tcp/c");
}
int tcp_close(client_ctx_t *ctx) {
return mpmc_queue(&mpmc_ctx, ctx);
}
void tcp_closer_stop(void) {
mpmc_stop(&mpmc_ctx);
}
void tcp_closer_destroy(void) {
mpmc_destroy(&mpmc_ctx);
}
static void tcp_closer_func(client_ctx_t *ctx) {
logger_set_prefix(ctx->log_prefix);
sock_close(&ctx->socket);
char buf[32];
clock_gettime(CLOCK_MONOTONIC, &ctx->end);
unsigned long micros = (ctx->end.tv_nsec - ctx->begin.tv_nsec) / 1000 + (ctx->end.tv_sec - ctx->begin.tv_sec) * 1000000;
info("Connection closed (%s)", format_duration(micros, buf));
memset(ctx, 0, sizeof(*ctx));
}

15
src/worker/tcp_closer.h Normal file
View File

@@ -0,0 +1,15 @@
#ifndef SESIMOS_TCP_CLOSER_H
#define SESIMOS_TCP_CLOSER_H
#include "../client.h"
int tcp_closer_init(int n_workers, int buf_size);
int tcp_close(client_ctx_t *ctx);
void tcp_closer_stop(void);
void tcp_closer_destroy(void);
#endif //SESIMOS_TCP_CLOSER_H