/*
 * a stream socket server demo
 */


#include <arpa/inet.h>
#include <errno.h>
#include <netinet/in.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>


#define MYPORT 1234             // the port users will be connecting to
#define BACKLOG 10              // how many pending connections queue will hold
#define MAXDATASIZE     1065537


static void
sigchld_handler(int s)
{
        while (waitpid(-1, NULL, WNOHANG) > 0) {
        }
}


int
main(int argc, char *argv[])
{
        int sockfd, new_fd;  // listen on sock_fd, new connection on new_fd
        struct sockaddr_in my_addr;     // my address information
        struct sockaddr_in their_addr; // connector's address information
        uint32_t sin_size;
        struct sigaction sa;
        int yes = 1;
        short int port = MYPORT;
        char buf[MAXDATASIZE];

        if (argc >= 2 && atoi(argv[1]) != 0)
                port = atoi(argv[1]);

        if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
                perror("socket");
                exit(1);
        }

        if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
                perror("setsockopt");
                exit(1);
        }

        memset(&my_addr, 0, sizeof(my_addr));
        my_addr.sin_family = AF_INET;
        my_addr.sin_port = htons(port);
        my_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP

        if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) {
                perror("bind");
                exit(1);
        }

        if (listen(sockfd, BACKLOG) == -1) {
                perror("listen");
                exit(1);
        }

        sa.sa_handler = sigchld_handler; // reap all dead processes
        sigemptyset(&sa.sa_mask);
#ifdef HAIKU_TARGET_PLATFORM_HAIKU
        sa.sa_flags = SA_RESTART;
#else
        sa.sa_flags = 0;
#endif
        if (sigaction(SIGCHLD, &sa, NULL) == -1) {
                perror("sigaction");
                exit(1);
        }

        while (1) {
                // main accept() loop
                sin_size = sizeof(struct sockaddr_in);
                if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1) {
                        perror("accept");
                        continue;
                }
                printf("server: got connection from %s\n", inet_ntoa(their_addr.sin_addr));
                if (!fork()) { // this is the child process
                        close(sockfd); // child doesn't need the listener

                        if (!fork()) {
                                while (1) {
                                        // child's child process
                                        if (fgets(buf, MAXDATASIZE, stdin) == NULL) {
                                                perror("fgets");
                                                exit(1);
                                        }

                                        if (!strcmp(buf, "full\n")) {
                                                int i;
puts("HY");
                                                for (i = 0; i < MAXDATASIZE - 2; i++) {
                                                        buf[i] = 'a' + (i % 26);
                                                }
                                                buf[MAXDATASIZE - 2] = '\n';
                                                buf[MAXDATASIZE - 1] = '\0';
                                        }

                                        if (send(new_fd, buf, strlen(buf), 0) == -1) {
                                                perror("send");
                                                exit(1);
                                        }
                                }
                        } else {
                                ssize_t numBytes;
                                while (1) {
                                        // child process
                                        if ((numBytes = recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
                                                perror("recv");
                                                exit(1);
                                        }
                                        if (numBytes == 0)
                                                exit(0);

                                        buf[numBytes] = '\0';

                                        printf("%s:| %s", inet_ntoa(their_addr.sin_addr), buf);
                                }
                        }

                        close(new_fd);
                        exit(0);
                }
                close(new_fd);  // parent doesn't need this
        }

        return 0;
}