update code

Makefile

@@ -1,6 +1,6 @@
 
 BIN=smartdns 
-OBJS=smartdns.o fast_ping.o lib/bitops.o dns_client.o
+OBJS=smartdns.o fast_ping.o lib/bitops.o dns_client.o dns_server.o
 CFLAGS=-g -O0 -Wall
 CFLAGS +=-Iinclude
 CXXFLAGS=-g -O0 -Wall -std=c++11

dns_server.c

@@ -0,0 +1,219 @@
+#include "dns_server.h"
+#include "hashtable.h"
+#include <arpa/inet.h>
+#include <errno.h>
+#include <linux/filter.h>
+#include <netdb.h>
+#include <netinet/icmp6.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/ip_icmp.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/epoll.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#define DNS_MAX_EVENTS 256
+
+#define DNS_INPACKET_SIZE 512
+
+struct dns_server {
+    int run;
+    int epoll_fd;
+
+    int fd;
+
+    pthread_mutex_t map_lock;
+    DECLARE_HASHTABLE(hostmap, 6);
+};
+
+static struct dns_server server;
+
+static void tv_sub(struct timeval *out, struct timeval *in)
+{
+    if ((out->tv_usec -= in->tv_usec) < 0) { /* out -= in */
+        --out->tv_sec;
+        out->tv_usec += 1000000;
+    }
+    out->tv_sec -= in->tv_sec;
+}
+
+void _dns_server_period_run()
+{
+}
+
+static int _dns_server_process(struct timeval *now)
+{
+    int len;
+    u_char inpacket[DNS_INPACKET_SIZE];
+    struct sockaddr_storage from;
+    socklen_t from_len = sizeof(from);
+
+    len = recvfrom(server.fd, inpacket, sizeof(inpacket), 0, (struct sockaddr *)&from, (socklen_t *)&from_len);
+    if (len < 0) {
+        fprintf(stderr, "recvfrom failed, %s\n", strerror(errno));
+        goto errout;
+    }
+
+    return 0;
+errout:
+    return -1;
+}
+
+int dns_server_run(void)
+{
+    struct epoll_event events[DNS_MAX_EVENTS + 1];
+    int num;
+    int i;
+    struct timeval last = { 0 };
+    struct timeval now = { 0 };
+    struct timeval diff = { 0 };
+    uint millisec = 0;
+
+    while (server.run) {
+        diff = now;
+        tv_sub(&diff, &last);
+        millisec = diff.tv_sec * 1000 + diff.tv_usec / 1000;
+        if (millisec >= 100) {
+            _dns_server_period_run();
+            last = now;
+        }
+
+        num = epoll_wait(server.epoll_fd, events, DNS_MAX_EVENTS, 100);
+        if (num < 0) {
+            gettimeofday(&now, 0);
+            usleep(100000);
+            continue;
+        }
+
+        if (num == 0) {
+            gettimeofday(&now, 0);
+            continue;
+        }
+
+        gettimeofday(&now, 0);
+        for (i = 0; i < num; i++) {
+            struct epoll_event *event = &events[i];
+            _dns_server_process(&now);
+        }
+    }
+
+    close(server.epoll_fd);
+    server.epoll_fd = -1;
+
+    return 0;
+}
+
+static struct addrinfo *_dns_server_getaddr(const char *host, int port, int type, int protocol)
+{
+    struct addrinfo hints;
+    struct addrinfo *result = NULL;
+
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = type;
+    hints.ai_protocol = protocol;
+    if (getaddrinfo(host, port, &hints, &result) != 0) {
+        fprintf(stderr, "get addr info failed. %s\n", strerror(errno));
+        goto errout;
+    }
+
+    return result;
+errout:
+    if (result) {
+        freeaddrinfo(result);
+    }
+    return NULL;
+}
+
+int dns_server_socket(void)
+{
+    int fd = -1;
+    struct addrinfo *gai = NULL;
+
+    gai = _dns_server_getaddr(NULL, 53, SOCK_DGRAM, 0);
+
+    fd = socket(gai->ai_family, gai->ai_socktype, gai->ai_protocol);
+    if (fd < 0) {
+        fprintf(stderr, "create socket failed.\n");
+        goto errout;
+    }
+
+    if (bind() != 0) {
+        fprintf(stderr, "bind failed.\n");
+        goto errout;
+    }
+
+    server.fd = fd;
+    freeaddrinfo(gai);
+
+    return 0;
+errout:
+    if (fd > 0) {
+        close(fd);
+    }
+
+    if (gai) {
+        freeaddrinfo(gai);
+    }
+    return -1;
+}
+
+int dns_server_init(void)
+{
+    pthread_attr_t attr;
+    int epollfd = -1;
+    int fd = -1;
+
+    if (server.epoll_fd > 0) {
+        return -1;
+    }
+
+    memset(&server, 0, sizeof(server));
+    pthread_attr_init(&attr);
+
+    epollfd = epoll_create1(EPOLL_CLOEXEC);
+    if (epollfd < 0) {
+        fprintf(stderr, "create epoll failed, %s\n", strerror(errno));
+        goto errout;
+    }
+
+    pthread_mutex_init(&server.map_lock, 0);
+    hash_init(server.hostmap);
+    server.epoll_fd = epollfd;
+    server.fd = fd;
+    server.run = 1;
+
+    return 0;
+errout:
+    server.run = 0;
+
+    if (fd > 0) {
+        close(fd);
+    }
+
+    if (epollfd) {
+        close(epollfd);
+    }
+
+    pthread_mutex_destroy(&server.map_lock);
+
+    return -1;
+}
+
+void dns_server_exit(void)
+{
+    server.run = 0;
+
+    if (server.fd > 0) {
+        close(server.fd);
+        server.fd = -1;
+    }
+
+    pthread_mutex_destroy(&server.map_lock);
+}

dns_server.h

@@ -0,0 +1,10 @@
+#ifndef _SMART_DNS_SERVER_H
+#define _SMART_DNS_SERVER_H
+
+int dns_server_init(void);
+
+int dns_server_run(void);
+
+void dns_server_exit(void);
+
+#endif

smartdns.c

@@ -1,4 +1,6 @@
 #include "fast_ping.h"
+#include "dns_client.h"
+#include "dns_server.h"
 #include "hashtable.h"
 #include "list.h"
 #include <stdio.h>
@@ -26,6 +28,12 @@ int smartdns_init()
 
     fast_ping_result_callback(smartdns_ping_result);
 
+    ret = dns_server_init();
+    if (ret != 0) {
+        fprintf(stderr, "start dns server failed.\n");
+        goto errout;
+    }
+
     ret = dns_client_init();
     if (ret != 0) {
         fprintf(stderr, "start dns client failed.\n");
@@ -40,16 +48,7 @@ errout:
 
 int smartdns_run()
 {
-    fast_ping_start("192.168.1.1", 2000, 0);
-    fast_ping_start("192.168.1.35", 2000, 0);
-    fast_ping_start("14.215.177.38", 2000, 0);
-    fast_ping_start("113.96.161.87", 2000, 0);
-    fast_ping_start("::1", 2000, 0);
-    fast_ping_start("12.4.3.1", 1000, 0);
-    while (1) {
-        sleep(10);
-        //fast_ping_stop("192.168.1.35");
-    }
+    return dns_server_run();
 }
 
 void smartdns_exit()
@@ -57,6 +56,8 @@ void smartdns_exit()
     fast_ping_exit();
 
     dns_client_exit();
+
+    dns_server_exit();
 }
 
 struct data {