server.c: a basic multithreaded server to handle connectionsHEADmain

Signed-off-by: Anna (navi) Figueiredo Gomes <navi@vlhl.dev>

1 files changed, 160 insertions, 0 deletions

diff --git a/src/server.c b/src/server.c
new file mode 100644
index 0000000..66c1ac5
--- /dev/null
+++ b/src/server.c
@@ -0,0 +1,160 @@
+#include <assert.h>
+#include <stdbool.h>
+#include <pthread.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "server.h"
+#include "buffer.h"
+#include "http.h"
+
+static bool enqueue(struct fd_queue *queue, int fd) {
+	if (queue->count == MAX_FD_QUEUE) {
+		return false;
+	}
+
+	queue->queue[queue->back] = fd;
+	queue->count++;
+	queue->back = (queue->back + 1) % MAX_FD_QUEUE;
+
+	return true;
+}
+
+static int dequeue(struct fd_queue *queue) {
+	if (queue->count == 0) {
+		return -1;
+	}
+
+	int fd = queue->queue[queue->front];
+	queue->count--;
+	queue->front = (queue->front + 1) % MAX_FD_QUEUE;
+
+	return fd;
+}
+
+static void *handle_connection(void *data) {
+	assert(data);
+	struct thread_data *tdata = (struct thread_data*)data;
+	int fd = -1;
+	char buf[BUFSIZ + 1];
+	ssize_t rlen;
+	struct buffer *request_buf, *reply_buf;
+	struct reply *reply;
+
+	while(true) {
+		pthread_mutex_lock(&tdata->lock);
+		fd = dequeue(&tdata->queue);
+		if (fd == -1) {
+			pthread_cond_wait(&tdata->cond, &tdata->lock);
+			fd = dequeue(&tdata->queue);
+		}
+		pthread_mutex_unlock(&tdata->lock);
+
+		printf("got fd %d\n", fd);
+
+		if ((rlen = read(fd, buf, BUFSIZ)) < 0) {
+			perror("read failed");
+			close(fd);
+			continue;
+		}
+
+		buf[rlen] = '\0';
+		request_buf = buf_new(buf);
+		
+		while (rlen >= BUFSIZ) {
+			if ((rlen = read(fd, buf, BUFSIZ)) < 0) {
+				perror("read failed");
+				close(fd);
+				continue;
+			}
+			buf[rlen] = '\0';
+			buf_append(request_buf, buf);
+		}
+
+		reply = http_handle_request(tdata->http, request_buf);
+		reply_buf = http_build_reply(reply);
+		free(reply);
+
+		write(fd, reply_buf->data, reply_buf->size);
+
+		buf_del(&reply_buf);
+		buf_del(&request_buf);
+
+		close(fd);
+	}
+}
+
+struct server *server_init(struct http *http) {
+	struct server *server = malloc(sizeof(struct server));
+
+	server->server_fd = socket(AF_INET, SOCK_STREAM, 0);
+	if (server->server_fd < 0) {
+		perror("socket failure");
+		return NULL;
+	}
+
+	struct sockaddr_in addr = {
+		.sin_family = AF_INET,
+		.sin_addr.s_addr = INADDR_ANY,
+		.sin_port = htons(45748),
+	};
+
+	int addrlen = sizeof(addr);
+	int opt = 1;
+
+	if (setsockopt(server->server_fd, SOL_SOCKET, SO_REUSEADDR,
+				&opt, sizeof(opt)) < 0) {
+		perror("setsockopt failed");
+		return NULL;
+	}
+
+	if (bind(server->server_fd, (struct sockaddr*)&addr, addrlen) < 0) {
+		perror("bind failed");
+		return NULL;
+	}
+
+	if (listen(server->server_fd, 16) < 0) {
+		perror("listen failed");
+		return NULL;
+	}
+
+	server->addr = addr;
+	server->addrlen = addrlen;
+	server->thread_pool_size = THREAD_POOL_NUM;
+	server->data.http = http;
+	server->pool = calloc(server->thread_pool_size, sizeof(pthread_t));
+	pthread_mutex_init(&server->data.lock, NULL);
+	pthread_cond_init(&server->data.cond, NULL);
+	server->data.queue.back = -1;
+	server->data.queue.front = -1;
+	server->data.queue.count = 0;
+
+	for (size_t i = 0; i < server->thread_pool_size; i++) {
+		pthread_create(&server->pool[i], NULL, handle_connection, &server->data);
+	}
+
+	return server;
+}
+
+void server_poll(struct server *server) {
+	int client_fd;
+
+	while (true) {
+		if ((client_fd = accept(server->server_fd, (struct sockaddr*)&server->addr,
+						(socklen_t*)&server->addrlen)) < 0) {
+			perror("accept failed");
+			return;
+		}
+
+		printf("connection accepted on fd %d\n", client_fd);
+
+		pthread_mutex_lock(&server->data.lock);
+		enqueue(&server->data.queue, client_fd);
+		pthread_cond_signal(&server->data.cond);
+		pthread_mutex_unlock(&server->data.lock);
+
+	}
+}