Морозов Евгений, 3530901/70203 lab1b

CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.0)
+project(messenger)
+add_executable(client src/client.cpp)
+add_executable(server src/server.cpp)
+find_library(PH pthread)
+target_link_libraries(server ${PH})
+target_link_libraries(client ${PH})

src/client.cpp

@@ -0,0 +1,126 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <pthread.h>
+
+
+#define DEF_PORT 8888
+#define DEF_IP "127.0.0.1"
+int readFix(int sock, char** buf, char** name, long* time, int flags);
+int sendFix(int sock, char* buf, char* name, int flags);
+void* reader(void* arg) {
+    for (;;) {
+        int sock = *(int *) arg;
+        char* buf = nullptr;
+        char* name = nullptr;
+        time_t time;
+        int res = readFix(sock, &buf, &name, &time, 0);
+        if (res <= 0) {
+            perror("Error while receiving:");
+            exit(1);
+        }
+        time -= timezone;
+        printf("%s\t%10s:\t%s\n", ctime(&time),name,buf);
+        free(buf);
+        free(name);
+    }
+}
+int main( int argc, char** argv) {
+    tzset();
+    char* addr;
+    int port;
+    char* readbuf;
+    if(argc <3) {
+        printf("Using default port %d\n",DEF_PORT);
+        port = DEF_PORT;
+    } else
+        port = atoi(argv[2]);
+    if(argc < 2) {
+        printf("Using default addr %s\n",DEF_IP);
+        addr = DEF_IP;
+    } else
+        addr = argv[1];
+    // создаем сокет
+    struct sockaddr_in peer;
+    peer.sin_family = AF_INET;
+    peer.sin_port = htons( port );
+    peer.sin_addr.s_addr = inet_addr( addr );
+    int sock = socket( AF_INET, SOCK_STREAM, 0 );
+    if ( sock < 0 ){
+        perror( "Can't create socket\n" );
+        exit( 1 );
+    }
+    // присоединяемся к серверу
+    int res = connect( sock, ( struct sockaddr * )&peer, sizeof(peer ) );
+    if (res) {
+        perror( "Can't connect to server:" );
+        exit( 1 );
+    }
+    // основной цикл программы
+    char buf[100];
+    char name[20];
+    printf("Enter your name\n");
+    bzero(name, 20);
+    fgets(name, 20, stdin);
+    name[strlen(name)-1] = '\0';
+    pthread_t thr;
+    res = pthread_create(&thr,NULL,reader,(void*)&sock);
+    if (res) {
+        printf("Error while creating new thread\n");
+    }
+    for(;;) {
+        printf("Input request (empty to exit)\n");
+        bzero(buf,100);
+        fgets(buf, 100, stdin);
+        buf[strlen(buf)-1] = '\0';
+        if(strlen(buf) == 0) {
+            printf("Bye-bye\n");
+            return 0;
+        }
+        res = sendFix(sock, buf, name, 0);
+        if ( res <= 0 ) {
+            perror( "Error while sending:" );
+            exit( 1 );
+        }
+
+    }
+}
+int readFix(int sock, char** buf, char** name, long* time, int flags) {
+    // читаем "заголовок" - сколько байт составляет наше сообщение
+    unsigned msgLength = 0;
+    unsigned nameLength = 0;
+    int res=recv(sock,&msgLength,sizeof(unsigned),flags|MSG_WAITALL);
+    if (res <= 0)return res;
+    // читаем само сообщение
+    *buf = new char[msgLength+1];
+    bzero(*buf, msgLength+1);
+    res = recv(sock, *buf, msgLength, flags | MSG_WAITALL);
+    if (res <= 0) return res;
+    res = recv(sock, &nameLength, sizeof(unsigned), flags | MSG_WAITALL);
+    if (res <= 0) return res;
+    *name = new char[nameLength+1];
+    bzero(*name, nameLength+1);
+    res = recv(sock, *name, nameLength, flags | MSG_WAITALL);
+    if (res <= 0) return res;
+    res = recv(sock, time, sizeof(long), flags | MSG_WAITALL);
+    if (res <= 0) return res;
+    return 1;
+}
+int sendFix(int sock, char* buf, char* name, int flags) {
+    // число байт в сообщении
+    unsigned msgLength = strlen(buf);
+    unsigned nameLength = strlen(name);
+    int res = send(sock, &msgLength, sizeof(unsigned), flags );
+    if (res <= 0) return res;
+    res = send(sock, buf, msgLength, flags);
+    if (res <= 0) return res;
+    res = send(sock, &nameLength, sizeof(unsigned), flags);
+    if (res <= 0) return res;
+    res = send(sock, name, nameLength, flags);
+    if (res <= 0) return res;
+    return 1;
+}

src/server.cpp

@@ -0,0 +1,191 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <pthread.h>
+#include <set>
+#include <fcntl.h>
+#include <algorithm>
+#include <zconf.h>
+#include <cerrno>
+
+#define DEF_PORT 8888
+#define DEF_IP "127.0.0.1"
+std::set<int> clients;
+
+// обработка одного клиента
+int readFix(int sock, char **msg, char **name, long *time, int flags);
+
+int sendFix(int sock, char *buf, char *name, long *time, int flags);
+
+void *main_cycle(void *args) {
+    while (true) {
+        int listener = *(int *) args;
+        fd_set readset;
+        FD_ZERO(&readset);
+        FD_SET(listener, &readset);
+        for (auto it = clients.begin(); it != clients.end(); it++) {
+            FD_SET(*it, &readset);
+        }
+        timeval timeout;
+        timeout.tv_sec = 1;
+        timeout.tv_usec = 0;
+        int mx = std::max(listener, *std::max_element(clients.begin(), clients.end()));
+        int cnt = select(mx + 1, &readset, nullptr, nullptr, &timeout);
+        if (cnt == -1) {
+            perror("Failed select\n");
+            exit(5);
+        } else if (cnt == 0) continue;
+        if (FD_ISSET(listener, &readset)) {
+            int client = accept(listener, nullptr, nullptr);
+            if (client <= 0) {
+                perror("Failed accept\n");
+                exit(5);
+            }
+            fcntl(client, F_SETFL, O_NONBLOCK);
+            clients.insert(client);
+        }
+        for (auto it = clients.begin(); it != clients.end(); it++) {
+            if (FD_ISSET(*it, &readset)) {
+                char *buf = nullptr;
+                char *name = nullptr;
+                int res = 0;
+                long time;
+                res = readFix(*it, &buf, &name, &time, 0);
+                int err = errno; // save off errno, because because the printf statement might reset it
+                if (res < 0){
+                    if (err == EAGAIN){
+                        printf("non-blocking operation returned EAGAIN or EWOULDBLOCK\n");
+                        continue;
+                    }else{
+                        printf("recv returned unrecoverable error(errno=%d)\n", err);
+                        break;
+                    }
+                }
+                if (res < 0) {
+                    perror("Can't recv data from client\n");
+                    close(listener);
+                    clients.erase(*it);
+                    exit(1);
+                } else if (res == 0) {
+                    FD_CLR(*it, &readset);
+                    close(*it);
+                    printf("Disconnected client(%d)\n",*it);
+                    continue;
+                }
+                printf("%s\t%10s:%s\n", ctime(&time), name, buf);
+                for (int client : clients) {
+                    res = sendFix(client, buf, name, &time, 0);
+                    if (res < 0) {
+                        perror("send call failed");
+                        continue;
+                    }
+                }
+                free(name);
+                free(buf);
+
+            }
+        }
+    }
+}
+
+int main(int argc, char **argv) {
+    int port = 0;
+    if (argc < 2) {
+        printf("Using default port %d\n", DEF_PORT);
+        port = DEF_PORT;
+    } else
+        port = atoi(argv[1]);
+    struct sockaddr_in listenerInfo;
+    listenerInfo.sin_family = AF_INET;
+    listenerInfo.sin_port = htons(port);
+    listenerInfo.sin_addr.s_addr = htonl(INADDR_ANY);
+    int listener = socket(AF_INET, SOCK_STREAM, 0);
+    fcntl(listener, F_SETFL, O_NONBLOCK);
+    if (listener < 0) {
+        perror("Can't create socket to listen: ");
+        exit(1);
+    }
+    int res = bind(listener, (struct sockaddr *) &listenerInfo, sizeof(listenerInfo));
+    if (res < 0) {
+        perror("Can't bind socket");
+        exit(1);
+    }
+    // слушаем входящие соединения
+    res = listen(listener, 5);
+    if (res) {
+        perror("Error while listening:");
+        exit(1);
+    }
+    // основной цикл работы
+    pthread_t cycle;
+    res = pthread_create(&cycle, nullptr, main_cycle, (void *) (&listener));
+    if (res) {
+        printf("Error while creating new thread\n");
+    }
+    char input;
+    for (;;) {
+        input = (char) getchar();
+        if (input == 'q') {
+            exit(0);
+        }
+    }
+}
+ssize_t rec(int sock, void* data, size_t n, int flags) {
+    int res = 0;
+    int err = 0;
+    do {
+        res = recv(sock, data, n, flags);
+        err = errno; // save off errno, because because the printf statement might reset it
+        if (res < 0){
+            if (err == EAGAIN){
+            }else{
+                printf("recv returned unrecoverable error(errno=%d)\n", err);
+                break;
+            }
+        }
+    } while (err == EAGAIN && res < 0);
+    return res;
+}
+
+int readFix(int sock, char **msg, char **name, long *time, int flags) {
+    // читаем "заголовок" - сколько байт составляет наше сообщение
+    unsigned msgLength = 0;
+    unsigned nameLength = 0;
+    struct tm *t;
+    int res = rec(sock, &msgLength, sizeof(unsigned), flags);
+    if (res <= 0)return res;
+    // читаем само сообщение
+    *msg = new char[msgLength + 1];
+    bzero(*msg, msgLength + 1);
+    res = rec(sock, *msg, msgLength, flags);
+    if (res <= 0) return res;
+    res = rec(sock, &nameLength, sizeof(unsigned), flags);
+    if (res <= 0) return res;
+    *name = new char[nameLength + 1];
+    bzero(*name, nameLength + 1);
+    res = rec(sock, *name, nameLength, flags);
+    if (res <= 0) return res;
+    *time = ::time(nullptr);
+    t = gmtime(time);
+    *time = mktime(t);
+    return 1;
+}
+int sendFix(int sock, char *buf, char *name, long *time, int flags) {
+    // шлем число байт в сообщении
+    unsigned msgLength = strlen(buf);
+    unsigned nameLength = strlen(name);
+    int res = send(sock, &msgLength, sizeof(unsigned), flags);
+    if (res <= 0) return res;
+    res = send(sock, buf, msgLength, flags);
+    if (res <= 0) return res;
+    res = send(sock, &nameLength, sizeof(unsigned), flags);
+    if (res <= 0) return res;
+    res = send(sock, name, nameLength, flags);
+    if (res <= 0) return res;
+    res = send(sock, time, sizeof(long), flags);
+    if (res <= 0) return res;
+    return 1;
+}