The libfiber project comes from the coroutine module of the acl project in lib_fiber directory of which. It can be used on OS platfroms including Linux, FreeBSD, MacOS, and Windows, which supports select, poll, epoll, io-uring, kqueue, iocp, and even Windows GUI messages for different platfrom. With libfiber, you can write network application services having the high performance and large cocurrent more easily than the traditional asynchronus framework with event-driven model. What's more, with the help of libfiber, you can even write network module of the Windows GUI application written by MFC, wtl or other GUI framework on Windows in coroutine way. That's realy amazing.
The libfiber supports many events including select/poll/epoll/io-uring/kqueue/iocp, and Windows GUI messages.
| Platform | Event type |
|---|---|
| Linux | select, poll, epoll, io-uring |
| BSD | select, poll, kqueue |
| Mac | select, poll, kqueue |
| Windows | select, poll, iocp, GUI Message |
// fiber_server.c
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "fiber/lib_fiber.h"
#include "patch.h" // in the samples path
static size_t __stack_size = 128000;
static const char *__listen_ip = "127.0.0.1";
static int __listen_port = 9001;
static void fiber_client(ACL_FIBER *fb, void *ctx)
{
SOCKET *pfd = (SOCKET *) ctx;
char buf[8192];
while (1) {
#if defined(_WIN32)
int ret = acl_fiber_recv(*pfd, buf, sizeof(buf), 0);
#else
int ret = recv(*pfd, buf, sizeof(buf), 0);
#endif
if (ret == 0) {
break;
} else if (ret < 0) {
if (acl_fiber_last_error() == FIBER_EINTR) {
continue;
}
break;
}
#if defined(_WIN32)
if (acl_fiber_send(*pfd, buf, ret, 0) < 0) {
#else
if (send(*pfd, buf, ret, 0) < 0) {
#endif
break;
}
}
socket_close(*pfd);
free(pfd);
}
static void fiber_accept(ACL_FIBER *fb, void *ctx)
{
const char *addr = (const char *) ctx;
SOCKET lfd = socket_listen(__listen_ip, __listen_port);
assert(lfd >= 0);
for (;;) {
SOCKET *pfd, cfd = socket_accept(lfd);
if (cfd == INVALID_SOCKET) {
printf("accept error %s\r\n", acl_fiber_last_serror());
break;
}
pfd = (SOCKET *) malloc(sizeof(SOCKET));
*pfd = cfd;
// create and start one fiber to handle the client socket IO
acl_fiber_create(fiber_client, pfd, __stack_size);
}
socket_close(lfd);
exit (0);
}
// FIBER_EVENT_KERNEL represents the event type on
// Linux(epoll), BSD(kqueue), Mac(kqueue), Windows(iocp)
// FIBER_EVENT_POLL: poll on Linux/BSD/Mac/Windows
// FIBER_EVENT_SELECT: select on Linux/BSD/Mac/Windows
// FIBER_EVENT_WMSG: Win GUI message on Windows
// acl_fiber_create/acl_fiber_schedule_with are in `lib_fiber.h`.
// socket_listen/socket_accept/socket_close are in patch.c of the samples path.
int main(void)
{
int event_mode = FIBER_EVENT_KERNEL;
#if defined(_WIN32)
socket_init();
#endif
// create one fiber to accept connections
acl_fiber_create(fiber_accept, NULL, __stack_size);
// start the fiber schedule process
acl_fiber_schedule_with(event_mode);
#if defined(_WIN32)
socket_end();
#endif
return 0;
}// fiber_client.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "fiber/lib_fiber.h"
#include "patch.h" // in the samples path
static const char *__server_ip = "127.0.0.1";
static int __server_port = 9001;
// socket_init/socket_end/socket_connect/socket_close are in patch.c of the samples path
static void fiber_client(ACL_FIBER *fb, void *ctx)
{
SOCKET cfd = socket_connect(__server_ip, __server_port);
const char *s = "hello world\r\n";
char buf[8192];
int i, ret;
if (cfd == INVALID_SOCKET) {
return;
}
for (i = 0; i < 1024; i++) {
#if defined(_WIN32)
if (acl_fiber_send(cfd, s, strlen(s), 0) <= 0) {
#else
if (send(cfd, s, strlen(s), 0) <= 0) {
#endif
printf("send error %s\r\n", acl_fiber_last_serror());
break;
}
#if defined(_WIN32)
ret = acl_fiber_recv(cfd, buf, sizeof(buf), 0);
#else
ret = recv(cfd, buf, sizeof(buf), 0);
#endif
if (ret <= 0) {
break;
}
}
#if defined(_WIN32)
acl_fiber_close(cfd);
#else
close(cfd);
#endif
}
int main(void)
{
int event_mode = FIBER_EVENT_KERNEL;
size_t stack_size = 128000;
int i;
#if defined(_WIN32)
socket_init();
#endif
for (i = 0; i < 100; i++) {
acl_fiber_create(fiber_client, NULL, stack_size);
}
acl_fiber_schedule_with(event_mode);
#if defined(_WIN32)
socket_end();
#endif
return 0;
}#include "acl_cpp/lib_acl.hpp"
#include "fiber/libfiber.hpp"
class fiber_client : public acl::fiber {
public:
fiber_client(acl::socket_stream* conn) : conn_(conn) {}
private:
~fiber_client(void) { delete conn_; }
private:
acl::socket_stream* conn_;
// @override
void run(void) {
char buf[256];
while (true) {
int ret = conn_->read(buf, sizeof(buf), false);
if (ret <= 0) {
break;
}
if (conn_->write(buf, ret) != ret) {
break;
}
}
delete this;
}
};
class fiber_server : public acl::fiber {
public:
fiber_server(acl::server_socket& server) : server_(server) {}
private:
~fiber_server(void) {}
private:
acl::server_socket& server_;
// @override
void run(void) {
while (true) {
acl::socket_stream* conn = server_.accept();
if (conn) {
acl::fiber* fb = new fiber_client(conn);
fb->start();
}
}
delete this;
}
};
int main(void) {
const char* addr = "127.0.0.1:8088";
acl::server_socket server;
if (!server.open(addr)) {
return 1;
}
// Create one server coroutine to wait for connection.
acl::fiber* fb = new fiber_server(server);
fb->start();
acl::fiber::schedule(); // Start the coroutine scheculde process.
return 0;
}#include "acl_cpp/lib_acl.hpp"
#include "fiber/go_fiber.hpp"
int main(void) {
const char* addr = "127.0.0.1:8088";
acl::server_socket server;
if (!server.open(addr)) {
return 1;
}
// Create one server coroutine to wait for connection.
go[=, &server] {
while (true) {
acl::socket_stream* conn = server.accept();
if (conn) {
// Create one client coroutine to handle the connection.
go[conn] {
char buf[256];
while (true) {
int ret = conn->read(buf, sizeof(buf), false);
if (ret <= 0) {
break;
}
if (conn->write(buf, ret) != ret) {
break;
}
}
delete conn;
};
}
}
};
// acl::FIBER_EVENT_T_KERNEL,
// acl::FIBER_EVENT_T_POLL,
// acl::FIBER_EVENT_T_SELECT,
// acl::FIBER_EVENT_T_IO_URING(Linux5.1+)
// acl::FIBER_EVENT_T_WMSG(Win GUI)
acl::fiber_event_t type = acl::FIBER_EVENT_T_KERNEL;
acl::fiber::schedule_with(type); // Start the coroutine scheculde process.
return 0;
}There is one Windows GUI sample with libfiber in directory. The screen shot is 
The server coroutine and client coroutine are all running in the same thread as the GUI, so you can operate the GUI object in server and client coroutine without worrying about the memroy collision problem. And you can write network process with sequence way, other than asynchronus callback way which is so horrible. With the libfirber for Windows GUI, the asynchronus API like CAsyncSocket should be discarded. The network APIs are intergrated with the Windows GUI seamlessly because the libfiber using GUI message pump as event driven internal.
You can get more samples in samples, which use many APIs in acl project library.
$cd libfiber
$make
$cd samples
$make
The simple Makefile shown below:
fiber_server: fiber_server.c
gcc -o fiber_server fiber_server.c patch.c -I{path_of_fiber_header} -L{path_of_fiber_lib) -lfiber -ldl -lpthread
fiber_client: fiber_client.c
gcc -o fiber_client fiber_client.c patch.c -I{path_of_fiber_header} -L{path_of_fiber_lib) -lfiber -ldl -lpthread
You can build libfiber with vc2012/vc2013/vc2019.
The picture below show the IOPS (io echo per-second) benchmark written by libfiber, comparing with the samples writen by libmill, golang and libco. The samples written by libmill and libco are in directory, the sample written by golang is in here, and the sample written by libfiber is in server sample directory. The testing client is in here from the acl project.
- acl_fiber_create
- acl_fiber_self
- acl_fiber_status
- acl_fiber_kill
- acl_fiber_killed
- acl_fiber_signal
- acl_fiber_yield
- acl_fiber_ready
- acl_fiber_switch
- acl_fiber_schedule_init
- acl_fiber_schedule
- acl_fiber_schedule_with
- acl_fiber_scheduled
- acl_fiber_schedule_stop
- acl_fiber_set_specific
- acl_fiber_get_specific
- acl_fiber_delay
- acl_fiber_last_error
- acl_fiber_last_serror
- acl_fiber_recv
- acl_fiber_recvfrom
- acl_fiber_read
- acl_fiber_readv
- acl_fiber_recvmsg
- acl_fiber_write
- acl_fiber_writev
- acl_fiber_send
- acl_fiber_sendto
- acl_fiber_sendmsg
- acl_fiber_select
- acl_fiber_poll
- acl_fiber_close
- acl_fiber_socket
- acl_fiber_listen
- acl_fiber_accept
- acl_fiber_connect
- acl_fiber_gethostbyname_r
- acl_fiber_getaddrinfo
- acl_fiber_freeaddrinfo
- acl_channel_create
- acl_channel_free
- acl_channel_send
- acl_channel_send_nb
- acl_channel_recv
- acl_channel_recv_nb
- acl_channel_sendp
- acl_channel_recvp
- acl_channel_sendp_nb
- acl_channel_recvp_nb
- acl_channel_sendul
- acl_channel_recvul
- acl_channel_sendul_nb
- acl_channel_recvul_nb
ACL_FIBER_MUTEX
- acl_fiber_mutex_create
- acl_fiber_mutex_free
- acl_fiber_mutex_lock
- acl_fiber_mutex_trylock
- acl_fiber_mutex_unlock
ACL_FIBER_RWLOCK
- acl_fiber_rwlock_create
- acl_fiber_rwlock_free
- acl_fiber_rwlock_rlock
- acl_fiber_rwlock_tryrlock
- acl_fiber_rwlock_wlock
- acl_fiber_rwlock_trywlock
- acl_fiber_rwlock_runlock
- acl_fiber_rwlock_wunlock
ACL_FIBER_EVENT
- acl_fiber_event_create
- acl_fiber_event_free
- acl_fiber_event_wait
- acl_fiber_event_trywait
- acl_fiber_event_notify
ACL_FIBER_SEM
- acl_fiber_sem_create
- acl_fiber_sem_free
- acl_fiber_sem_wait
- acl_fiber_sem_post
- acl_fiber_sem_num
On Linux/BSD/Mac, many IO and Net APIs are hooked. So you can just use the System standard APIs in your applications with libfiber, the hooked APIs will be replaced with libfiber APIs. In this case, you can coroutine your DB application with mysql driven and change nothing in mysql driven.
The standard APIs been hooked are shown below:
- close
- sleep
- read
- readv
- recv
- recvfrom
- recvmsg
- write
- writev
- send
- sendto
- sendmsg
- sendfile64
- socket
- listen
- accept
- connect
- select
- poll
- epoll: epoll_create, epoll_ctl, epoll_wait
- gethostbyname(_r)
- getaddrinfo/freeaddrinfo
- Is the coroutine schedule in multi-threads?
No. The coroutine schedule of libfiber is in one single thread. But you can start multiple threads that one one thread has one schedule process. - How are the multi-cores of CPU used?
multiple threads can be started with its own coroutine schedule, each thread can ocpupy one CPU. - How does different threads mutex in coroutine schedule status?
Even though the OS system mutex APIs, such as pthread_mutex_t's APIs can be used, the ACL_FIBER_EVENT's APIs are recommended. It's safety when the OS system mutex APIs are used in short time without recursive invocation. But it's unsafety using system mutex APIs in this case: One coroutine A1 of thread A had locked the thread-mutex-A, the coroutine A2 of thread A wanted to lock the thread-mutex-B which had been locked by one coroutine B1 of thread B, when the coroutine B2 of thread B wanted to lock the thread-mutex-A, thread deadlock happened! So, the coroutine mutex for threads and coroutines named ACL_FIBER_EVENT's APIs of libfiber were created, which can be used to make critical region between multiple coroutines in different threads(multiple continues in the same thread or not; it can also be used for different threads without coroutines). - Should the mysql-driven source codes be changed when used with libfiber?
In UNIX OS, the System IO APIs are hooked by libfiber, so nothing should be changed in mysql-driven. - How to avoid make the mysqld overloaded when many coroutines started?
The ACL_FIBER_SEM's APIs can be used to protect the mysqld being overloaded by many connections of many coroutines. These APIs can limit the connections number to the mysqld from coroutines. - Does the DNS domain resolving block the coroutine schedule?
No, because the System domain-resolving APIs such as gethostbyname(_r) and getaddrinfo are also hooked in libfiber.