tevent_write.c

#include <tevent.h>
#include <stdio.h>
#include <unistd.h>

#ifndef TEVENT_FD_ERROR
#define TEVENT_FD_ERROR 0
#endif /* TEVENT_FD_ERROR */

static int fds[2];
struct tevent_fd *tfd;

static void timer_cb(struct tevent_context *c, struct tevent_timer *e,
                     struct timeval ct, void *data) {
    printf("[timer_cb]; error!\n");
    exit(-1);
}

static void error_cb(struct tevent_context *c, struct tevent_fd *e,
                     uint16_t fl, void *data) {
    printf("blue skied an' clear\n");
    exit(0);
}

static void read_cb(struct tevent_context *c, struct tevent_fd *e,
                    uint16_t fl, void *data) {
    int len;
    char buf[5];
    struct tevent_fd *tfd_new;

    printf("[read_cb]\n");

    /* verto_fire */
    len = read(fds[0], buf, 5);
    close(fds[0]);
    fds[0] = -1;
    tfd_new = tevent_add_fd(c, c, fds[1], TEVENT_FD_ERROR, read_cb,
                            (void *) c);
    if (!tfd_new) {
        printf("tevent_add_fd\n");
        exit(-1);
    }
    tevent_fd_set_flags(tfd_new, TEVENT_FD_WRITE);

    /* delete old CB */
    talloc_free(tfd);

    tfd = tfd_new;
}

static void write_cb(struct tevent_context *c, struct tevent_fd *e,
                     uint16_t fl, void *data) {
    struct tevent_fd *tfd_new;

    printf("[write_cb]\n");

    /* verto_fire */
    write(fds[1], "hello", 5);
    tfd_new = tevent_add_fd(c, c, fds[0], TEVENT_FD_ERROR, read_cb,
                            (void *) c);
    if (!tfd_new) {
        printf("tevent_add_fd\n");
        exit(-1);
    }
    tevent_fd_set_flags(tfd_new, TEVENT_FD_READ);

    /* delete old CB */
    talloc_free(tfd);

    tfd = tfd_new;
}

int main() {
    int ret;
    struct tevent_context *c;
    struct timeval tv;
    struct tevent_timer *timer;

    fds[0] = -1;
    fds[1] = -1;

    ret = pipe(fds);
    if (ret != 0) {
        printf("pipe\n");
        goto done;
    }
    
    c = tevent_context_init(NULL);
    if (!c) {
        printf("tevent_context_init\n");
        goto done;
    }

    /* verto_add_timeout */
    tv = tevent_timeval_current_ofs(1, 1000);
    timer = tevent_add_timer(c, c, tv, timer_cb, (void *) c);
    if (!timer) {
        printf("tevent_add_timer\n");
        goto done;
    }

    /* verto_add_io */
    tfd = tevent_add_fd(c, c, fds[1], TEVENT_FD_ERROR, write_cb, (void *) c);
    if (!tfd) {
        printf("tevent_add_fd\n");
        goto done;
    }
    tevent_fd_set_flags(tfd, TEVENT_FD_WRITE);

    while (1) {
        printf("[tevent_loop_once]\n");
        ret = tevent_loop_once(c);
        if (ret) {
            printf("tevent_loop_once\n");
            goto done;
        }
    }

done:
    return -1;
}