client.c

unix环境高级编程的源代码

#include    "calld.h"

static void
client_alloc(void)        /* alloc more entries in the client[] array */
{
    int        i;

    if (client == NULL)
        client = malloc(NALLOC * sizeof(Client));
    else
        client = realloc(client, (client_size + NALLOC) * sizeof(Client));
    if (client == NULL)
        err_sys("can't alloc for client array");

            /* have to initialize the new entries */
    for (i = client_size; i < client_size + NALLOC; i++)
        client[i].fd = -1;    /* fd of -1 means entry available */

    client_size += NALLOC;
}

/* Called by loop() when connection request from a new client arrives */

int
client_add(int fd, uid_t uid)
{
    int        i;

    if (client == NULL)        /* first time we're called */
        client_alloc();
again:
    for (i = 0; i < client_size; i++) {
        if (client[i].fd == -1) {    /* find an available entry */
            client[i].fd = fd;
            client[i].uid = uid;
            return(i);    /* return index in client[] array */
        }
    }
            /* client array full, time to realloc for more */
    client_alloc();
    goto again;        /* and search again (will work this time) */
}

/* Called by loop() when we're done with a client */

void
client_del(int fd)
{
    int        i;

    for (i = 0; i < client_size; i++) {
        if (client[i].fd == fd) {
            client[i].fd = -1;
            return;
        }
    }
    log_quit("can't find client entry for fd %d", fd);
}

/* Find the client entry corresponding to a process ID.
 * This function is called by the sig_chld() signal
 * handler only after a child has terminated. */

void
client_sigchld(pid_t pid, int stat)
{
    int        i;

    for (i = 0; i < client_size; i++) {
        if (client[i].pid == pid) {
            client[i].childdone = stat;    /* child's exit() status +1 */
            return;
        }
    }
    log_quit("can't find client entry for pid %d", pid);
}