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, 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/kqueue/iocp, and Windows GUI messages.
| Event | Linux | BSD | Mac | Windows |
|---|---|---|---|---|
| select | yes | yes | yes | yes |
| poll | yes | yes | yes | yes |
| epoll | yes | no | no | no |
| kqueue | no | yes | yes | no |
| iocp | no | no | no | yes |
| Win GUI message | no | no | no | yes |
// 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) {
#ifdef _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;
}
#ifdef _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;
#ifdef _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);
#ifdef _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++) {
#ifdef _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;
}
#ifdef _WIN32
ret = acl_fiber_recv(cfd, buf, sizeof(buf), 0);
#else
ret = recv(cfd, buf, sizeof(buf), 0);
#endif
if (ret <= 0) {
break;
}
}
#ifdef _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;
#ifdef _WIN32
socket_init();
#endif
for (i = 0; i < 100; i++) {
acl_fiber_create(fiber_client, NULL, stack_size);
}
acl_fiber_schedule_with(event_mode);
#ifdef _WIN32
socket_end();
#endif
return 0;
}The rfc1035 for DNS has been implement in libfiber, so you can call gethostbyname or getaddrinfo to get the givent domain's IP addresses in coroutine.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include "fiber/lib_fiber.h"
static void lookup(ACL_FIBER *fiber, void *ctx) {
char *name = (char *) ctx;
struct addrinfo hints, *res0;
int ret;
(void) fiber; // avoid compiler warning
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_V4MAPPED | AI_ADDRCONFIG;
ret = getaddrinfo(name, "80", &hints, &res0);
free(name);
if (ret != 0) {
printf("getaddrinfo error %s\r\n", gai_strerror(ret));
} else {
printf("getaddrinfo ok\r\n");
freeaddrinfo(res0);
}
}
int main(void) {
char *name1 = strdup("www.iqiyi.com");
char *name2 = strdup("www.baidu.com");
acl_fiber_create(lookup, name1, 128000);
acl_fiber_create(lookup, name2, 128000);
acl_fiber_schedule();
return 0;
}You can create one coroutine with standard C++ API in libfiber:
#include <stdio.h>
#include "fiber/libfiber.hpp"
class myfiber : public acl::fiber {
public:
myfiber(void) {}
private:
~myfiber(void) {}
protected:
// @override from acl::fiber
void run(void) {
printf("hello world!\r\n");
delete this;
}
};
int main(void) {
for (int i = 0; i < 10; i++) {
acl::fiber* fb = new myfiber();
fb->start();
}
acl::fiber::schedule();
return 0;
}You can also create one coroutine with c++11 API in libfiber:
#include <stdio.h>
#include "fiber/libfiber.hpp"
#include "fiber/go_fiber.hpp"
static void fiber_routine(int i) {
printf("hi, i=%d, curr fiber=%u\r\n", i, acl::fiber::self());
}
int main(void) {
for (int i = 0; i < 10; i++) {
go[=] {
fiber_routine(i);
};
}
acl::fiber::schedule();
return 0;
}#include <stdio.h>
#include <unistd.h>
#include "fiber/go_fiber.hpp"
static void fiber_routine(int i) {
go_wait[&] { // running in another thread
i += 100;
usleep(10000);
};
printf("i is %d\r\n", i);
}
int main(void) {
// create ten fibers
for (int i = 0; i < 10; i++) {
go[=] {
fiber_routine(i);
};
}
acl::fiber::schedule();
return 0;
}One http server written with libfiber and http module of acl supports http handler route which is in http server.
#include <acl-lib/acl_cpp/lib_acl.hpp> // must before http_server.hpp
#include <acl-lib/fiber/http_server.hpp>
static char *var_cfg_debug_msg;
static acl::master_str_tbl var_conf_str_tab[] = {
{ "debug_msg", "test_msg", &var_cfg_debug_msg },
{ 0, 0, 0 }
};
static int var_cfg_io_timeout;
static acl::master_int_tbl var_conf_int_tab[] = {
{ "io_timeout", 120, &var_cfg_io_timeout, 0, 0 },
{ 0, 0 , 0 , 0, 0 }
};
int main(void) {
acl::acl_cpp_init();
acl::http_server server;
// set the configure variables
server.set_cfg_int(var_conf_int_tab)
.set_cfg_str(var_conf_str_tab);
// set http handler route
server.Get("/", [](acl::HttpRequest&, acl::HttpResponse& res) {
acl::string buf("hello world1!\r\n");
res.setContentLength(buf.size());
return res.write(buf.c_str(), buf.size());
}).Post("/ok", [](acl::HttpRequest& req, acl::HttpResponse& res) {
acl::string buf;
req.getBody(buf);
res.setContentLength(buf.size());
return res.write(buf.c_str(), buf.size());
}).Get("/json", [&](acl::HttpRequest&, acl::HttpResponse& res) {
acl::json json;
acl::json_node& root = json.get_root();
root.add_number("code", 200)
.add_text("status", "+ok")
.add_child("data",
json.create_node()
.add_text("name", "value")
.add_bool("success", true)
.add_number("number", 200));
return res.write(json);
});
// start the server in alone mode
server.run_alone("0.0.0.0|8194, 127.0.0.1|8195", "./httpd.cf");
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 open the fiber_vc2012.sln/ fiber_vc2013.sln/c/fiber_vc2015.sln with vc2012/vc2013/vc2015, and build the libfiber library and the samples included.
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.