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webserver using libuv
An hello-world webserver in C using libuv ( and
http-parser ( based on Ryan Dahl's tutorial and updated to make it work with the most recent
libuv API.
Build it
git clone
git clone
Run it
Stress-test it
ab -n 5000 -c 500
Call for coders!
I have this insane idea of writing a lightweight c++ web framework on top of
libuv. But. I can't do it by myself.
Anyone crazy enough to join me? Drop me a tweet / email.
- Andrea
webserver: webserver.c libuv/uv.a http-parser/http_parser.o
gcc -I libuv/include \
-lrt -lm -lpthread -o \
webserver webserver.c \
libuv/uv.a http-parser/http_parser.o
$(MAKE) -C libuv
$(MAKE) -C http-parser http_parser.o
rm libuv/uv.a
rm http-parser/http_parser.o
rm webserver
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "libuv/include/uv.h"
#include "http-parser/http_parser.h"
#define CHECK(r, msg) \
if (r) { \
uv_err_t err = uv_last_error(uv_loop); \
fprintf(stderr, "%s: %s\n", msg, uv_strerror(err)); \
exit(1); \
#define UVERR(err, msg) fprintf(stderr, "%s: %s\n", msg, uv_strerror(err))
#define LOG(msg) puts(msg);
#define LOGF(fmt, params...) printf(fmt "\n", params);
#define LOG_ERROR(msg) puts(msg);
#define RESPONSE \
"HTTP/1.1 200 OK\r\n" \
"Content-Type: text/plain\r\n" \
"Content-Length: 12\r\n" \
"\r\n" \
"hello world\n"
static uv_loop_t* uv_loop;
static uv_tcp_t server;
static http_parser_settings parser_settings;
static uv_buf_t resbuf;
typedef struct {
uv_tcp_t handle;
http_parser parser;
uv_write_t write_req;
int request_num;
} client_t;
void on_close(uv_handle_t* handle) {
client_t* client = (client_t*) handle->data;
LOGF("[ %5d ] connection closed", client->request_num);
uv_buf_t on_alloc(uv_handle_t* client, size_t suggested_size) {
uv_buf_t buf;
buf.base = malloc(suggested_size);
buf.len = suggested_size;
return buf;
void on_read(uv_stream_t* tcp, ssize_t nread, uv_buf_t buf) {
size_t parsed;
client_t* client = (client_t*) tcp->data;
if (nread >= 0) {
parsed = http_parser_execute(
&client->parser, &parser_settings, buf.base, nread);
if (parsed < nread) {
LOG_ERROR("parse error");
uv_close((uv_handle_t*) &client->handle, on_close);
} else {
uv_err_t err = uv_last_error(uv_loop);
if (err.code != UV_EOF) {
UVERR(err, "read");
static int request_num = 1;
void on_connect(uv_stream_t* server_handle, int status) {
CHECK(status, "connect");
int r;
assert((uv_tcp_t*)server_handle == &server);
client_t* client = malloc(sizeof(client_t));
client->request_num = request_num;
LOGF("[ %5d ] new connection", request_num++);
uv_tcp_init(uv_loop, &client->handle);
http_parser_init(&client->parser, HTTP_REQUEST);
client-> = client;
client-> = client;
r = uv_accept(server_handle, (uv_stream_t*)&client->handle);
CHECK(r, "accept");
uv_read_start((uv_stream_t*)&client->handle, on_alloc, on_read);
void after_write(uv_write_t* req, int status) {
CHECK(status, "write");
uv_close((uv_handle_t*)req->handle, on_close);
int on_headers_complete(http_parser* parser) {
client_t* client = (client_t*) parser->data;
LOGF("[ %5d ] http message parsed", client->request_num);
return 1;
int main() {
int r;
parser_settings.on_headers_complete = on_headers_complete;
resbuf.base = RESPONSE;
resbuf.len = sizeof(RESPONSE);
uv_loop = uv_default_loop();
r = uv_tcp_init(uv_loop, &server);
CHECK(r, "bind");
struct sockaddr_in address = uv_ip4_addr("", 8000);
r = uv_tcp_bind(&server, address);
CHECK(r, "bind");
uv_listen((uv_stream_t*)&server, 128, on_connect);
LOG("listening on port 8000");

btw, I'm keeping a template server up to date with latest libuv here:


uv_run(uv_loop) need to add UV_RUN_DEFAULT as second parameter


You should update this demo, it doesn't compiles with the new version of libuv.

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