diff options
Diffstat (limited to 'manual/examples/inetsrv.c')
-rw-r--r-- | manual/examples/inetsrv.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/manual/examples/inetsrv.c b/manual/examples/inetsrv.c new file mode 100644 index 0000000000..bd86e80f36 --- /dev/null +++ b/manual/examples/inetsrv.c @@ -0,0 +1,103 @@ +#include <stdio.h> +#include <errno.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <netdb.h> + +#define PORT 5555 +#define MAXMSG 512 + +int +read_from_client (int filedes) +{ + char buffer[MAXMSG]; + int nbytes; + + nbytes = read (filedes, buffer, MAXMSG); + if (nbytes < 0) + { + /* Read error. */ + perror ("read"); + exit (EXIT_FAILURE); + } + else if (nbytes == 0) + /* End-of-file. */ + return -1; + else + { + /* Data read. */ + fprintf (stderr, "Server: got message: `%s'\n", buffer); + return 0; + } +} + +int +main (void) +{ + extern int make_socket (unsigned short int port); + int sock; + fd_set active_fd_set, read_fd_set; + int i; + struct sockaddr_in clientname; + size_t size; + + /* Create the socket and set it up to accept connections. */ + sock = make_socket (PORT); + if (listen (sock, 1) < 0) + { + perror ("listen"); + exit (EXIT_FAILURE); + } + + /* Initialize the set of active sockets. */ + FD_ZERO (&active_fd_set); + FD_SET (sock, &active_fd_set); + + while (1) + { + /* Block until input arrives on one or more active sockets. */ + read_fd_set = active_fd_set; + if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) < 0) + { + perror ("select"); + exit (EXIT_FAILURE); + } + + /* Service all the sockets with input pending. */ + for (i = 0; i < FD_SETSIZE; ++i) + if (FD_ISSET (i, &read_fd_set)) + { + if (i == sock) + { + /* Connection request on original socket. */ + int new; + size = sizeof (clientname); + new = accept (sock, + (struct sockaddr *) &clientname, + &size); + if (new < 0) + { + perror ("accept"); + exit (EXIT_FAILURE); + } + fprintf (stderr, + "Server: connect from host %s, port %hd.\n", + inet_ntoa (clientname.sin_addr), + ntohs (clientname.sin_port)); + FD_SET (new, &active_fd_set); + } + else + { + /* Data arriving on an already-connected socket. */ + if (read_from_client (i) < 0) + { + close (i); + FD_CLR (i, &active_fd_set); + } + } + } + } +} |