/*
 * Copyright (c) 2009 Mark Heily <mark@heily.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */


#include "common.h"


/*
 * Create a connected TCP socket.
 */
static void
create_socket_connection(int *client, int *server, const short port) 
{ 
    struct sockaddr_in sain;
    socklen_t sa_len = sizeof(sain);
    int one = 1;
    int clnt, srvr, accepted;

    /* Create a passive socket */
    memset(&sain, 0, sizeof(sain));
    sain.sin_family = AF_INET;
    sain.sin_port = htons(port);
    if ((srvr = socket(PF_INET, SOCK_STREAM, 0)) < 0) 
	err(1, "socket");
    if (setsockopt(srvr, SOL_SOCKET, SO_REUSEADDR, 
                (char *) &one, sizeof(one)) != 0) 
	err(1, "setsockopt");
    if (bind(srvr, (struct sockaddr *) &sain, sa_len) < 0) {
        printf("unable to bind to port %d\n", port);
        err(1, "bind-1");
    }
    if (listen(srvr, 100) < 0)
	err(1, "listen");

    /* Simulate a client connecting to the server */
    sain.sin_family = AF_INET;
    sain.sin_port = htons(port);
    sain.sin_addr.s_addr = inet_addr("127.0.0.1");
    if ((clnt = socket(AF_INET, SOCK_STREAM, 0)) < 0)
       err(1, "clnt: socket"); 
    if (connect(clnt, (struct sockaddr *) &sain, sa_len) < 0)
       err(1, "clnt: connect"); 
    if ((accepted = accept(srvr, NULL, 0)) < 0)
       err(1, "srvr: accept"); 

    *client = clnt;
    *server = accepted;
}

static void
kevent_socket_drain(struct test_context *ctx)
{
    char buf[1];

    /* Drain the read buffer, then make sure there are no more events. */
    if (recv(ctx->client_fd, &buf[0], 1, 0) < 1)
        die("recv(2)");
}

static void
kevent_socket_fill(struct test_context *ctx)
{
    if (send(ctx->server_fd, ".", 1, 0) < 1)
        die("send(2)");
}


void
test_kevent_socket_add(struct test_context *ctx)
{
    struct kevent kev;

    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_ADD, 0, 0, &ctx->client_fd);
}

void
test_kevent_socket_add_without_ev_add(struct test_context *ctx)
{
    struct kevent kev;

    /* Try to add a kevent without specifying EV_ADD */
    EV_SET(&kev, ctx->client_fd, EVFILT_READ, 0, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) == 0)
        die("kevent should have failed");

    kevent_socket_fill(ctx);
    test_no_kevents(ctx->kqfd);
    kevent_socket_drain(ctx);

    /* Try to delete a kevent which does not exist */
    kev.flags = EV_DELETE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) == 0)
        die("kevent should have failed");
}

void
test_kevent_socket_get(struct test_context *ctx)
{
    struct kevent kev, ret;

    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_ADD, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent:1");

    kevent_socket_fill(ctx);

    kev.data = 1;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret);

    kevent_socket_drain(ctx);
    test_no_kevents(ctx->kqfd);

    kev.flags = EV_DELETE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent:2");
}

void
test_kevent_socket_clear(struct test_context *ctx)
{
    struct kevent kev, ret;

    test_no_kevents(ctx->kqfd);
    kevent_socket_drain(ctx);

    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent1");

    kevent_socket_fill(ctx);
    kevent_socket_fill(ctx);

/* Solaris does not offer a way to get the amount of data pending */
#if defined(__sun__)
    kev.data = 1;
#else
    kev.data = 2;
#endif
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 

    /* We filled twice, but drain once. Edge-triggered would not generate
       additional events.
     */
    kevent_socket_drain(ctx);
    test_no_kevents(ctx->kqfd);

    kevent_socket_drain(ctx);
    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_DELETE, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent2");
}

void
test_kevent_socket_disable_and_enable(struct test_context *ctx)
{
    struct kevent kev, ret;

    /* Add an event, then disable it. */
    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_ADD, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");
    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_DISABLE, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");

    kevent_socket_fill(ctx);
    test_no_kevents(ctx->kqfd);

    /* Re-enable the knote, then see if an event is generated */
    kev.flags = EV_ENABLE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");
    kev.flags = EV_ADD;
    kev.data = 1;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 

    kevent_socket_drain(ctx);

    kev.flags = EV_DELETE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");
}

void
test_kevent_socket_del(struct test_context *ctx)
{
    struct kevent kev;

    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_DELETE, 0, 0, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");

    kevent_socket_fill(ctx);
    test_no_kevents(ctx->kqfd);
    kevent_socket_drain(ctx);
}

void
test_kevent_socket_oneshot(struct test_context *ctx)
{
    struct kevent kev, ret;

    /* Re-add the watch and make sure no events are pending */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, &ctx->client_fd);
    test_no_kevents(ctx->kqfd);

    kevent_socket_fill(ctx);
    kev.data = 1;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 

    test_no_kevents(ctx->kqfd);

    /* Verify that the kernel watch has been deleted */
    kevent_socket_fill(ctx);
    test_no_kevents(ctx->kqfd);
    kevent_socket_drain(ctx);

    /* Verify that the kevent structure does not exist. */
    kev.flags = EV_DELETE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) == 0)
        die("kevent() should have failed");
}

/*
 * Test if the data field returns 1 when a listen(2) socket has
 * a pending connection.
 */
void
test_kevent_socket_listen_backlog(struct test_context *ctx)
{
    struct kevent kev, ret;
    struct sockaddr_in sain;
    socklen_t sa_len = sizeof(sain);
    int one = 1;
    short port;
    int clnt, srvr;

    port = 14973 + ctx->iteration;

    /* Create a passive socket */
    memset(&sain, 0, sizeof(sain));
    sain.sin_family = AF_INET;
    sain.sin_port = htons(port);
    if ((srvr = socket(PF_INET, SOCK_STREAM, 0)) < 0) 
        err(1, "socket()");
    if (setsockopt(srvr, SOL_SOCKET, SO_REUSEADDR, 
                (char *) &one, sizeof(one)) != 0)
        err(1, "setsockopt()");
    if (bind(srvr, (struct sockaddr *) &sain, sa_len) < 0)
        err(1, "bind-2", port);
    if (listen(srvr, 100) < 0)
        err(1, "listen()");

    /* Watch for events on the socket */
    test_no_kevents(ctx->kqfd);
    kevent_add(ctx->kqfd, &kev, srvr, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, NULL);
    test_no_kevents(ctx->kqfd);

    /* Simulate a client connecting to the server */
    sain.sin_family = AF_INET;
    sain.sin_port = htons(port);
    sain.sin_addr.s_addr = inet_addr("127.0.0.1");
    if ((clnt = socket(AF_INET, SOCK_STREAM, 0)) < 0)
        err(1, "socket()");
    if (connect(clnt, (struct sockaddr *) &sain, sa_len) < 0)
        err(1, "connect()");

    /* Verify that data=1 */
    kev.data = 1;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 
    test_no_kevents(ctx->kqfd);
}

#ifdef EV_DISPATCH
void
test_kevent_socket_dispatch(struct test_context *ctx)
{
    struct kevent kev, ret;

    /* Re-add the watch and make sure no events are pending */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_ADD | EV_DISPATCH, 0, 0, &ctx->client_fd);
    test_no_kevents(ctx->kqfd);

    /* The event will occur only once, even though EV_CLEAR is not
       specified. */
    kevent_socket_fill(ctx);
    kev.data = 1;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 
    test_no_kevents(ctx->kqfd);

    /* Re-enable the kevent */
    /* FIXME- is EV_DISPATCH needed when rearming ? */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_ENABLE | EV_DISPATCH, 0, 0, &ctx->client_fd);
    kev.data = 1;
    kev.flags = EV_ADD | EV_DISPATCH;   /* FIXME: may not be portable */
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 
    test_no_kevents(ctx->kqfd);

    /* Since the knote is disabled, the EV_DELETE operation succeeds. */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_DELETE, 0, 0, &ctx->client_fd);

    kevent_socket_drain(ctx);
}
#endif  /* EV_DISPATCH */

#if BROKEN_ON_LINUX
void
test_kevent_socket_lowat(struct test_context *ctx)
{
    struct kevent kev;

    test_begin(test_id);

    /* Re-add the watch and make sure no events are pending */
    puts("-- re-adding knote, setting low watermark to 2 bytes");
    EV_SET(&kev, ctx->client_fd, EVFILT_READ, EV_ADD | EV_ONESHOT, NOTE_LOWAT, 2, &ctx->client_fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("%s", test_id);
    test_no_kevents();

    puts("-- checking that one byte does not trigger an event..");
    kevent_socket_fill(ctx);
    test_no_kevents();

    puts("-- checking that two bytes triggers an event..");
    kevent_socket_fill(ctx);
    if (kevent(ctx->kqfd, NULL, 0, &kev, 1, NULL) != 1)
        die("%s", test_id);
    KEV_CMP(kev, ctx->client_fd, EVFILT_READ, 0);
    test_no_kevents();

    kevent_socket_drain(ctx);
    kevent_socket_drain(ctx);
}
#endif

void
test_kevent_socket_eof(struct test_context *ctx)
{
    struct kevent kev, ret;

    /* Re-add the watch and make sure no events are pending */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_ADD, 0, 0, &ctx->client_fd);
    test_no_kevents(ctx->kqfd);

    //if (shutdown(ctx->server_fd, SHUT_RDWR) < 0)
    //    die("close(2)");
    if (close(ctx->server_fd) < 0)
        die("close(2)");

    kev.flags |= EV_EOF;
    kevent_get(&ret, ctx->kqfd);
    kevent_cmp(&kev, &ret); 

    /* Delete the watch */
    kevent_add(ctx->kqfd, &kev, ctx->client_fd, EVFILT_READ, EV_DELETE, 0, 0, &ctx->client_fd);
}

/* Test if EVFILT_READ works with regular files */
void
test_kevent_regular_file(struct test_context *ctx)
{
    struct kevent kev, ret;
    off_t curpos;
    int fd;

    fd = open("/etc/hosts", O_RDONLY);
    if (fd < 0)
        abort();

    EV_SET(&kev, fd, EVFILT_READ, EV_ADD, 0, 0, &fd);
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");

    kevent_get(&ret, ctx->kqfd);

    /* Set file position to EOF-1 */
    ret.data--;
    if ((curpos = lseek(fd, ret.data, SEEK_SET)) != ret.data) {
        printf("seek to %u failed with rv=%lu\n", 
                (unsigned int) ret.data, (unsigned long) curpos);
        abort();
    }

    /* Set file position to EOF */
    kevent_get(NULL, ctx->kqfd);
    ret.data = curpos + 1;
    if ((curpos = lseek(fd, ret.data, SEEK_SET)) != ret.data) {
        printf("seek to %u failed with rv=%lu\n",
                (unsigned int) ret.data, (unsigned long) curpos);
        abort();
    }

    test_no_kevents(ctx->kqfd);

    kev.flags = EV_DELETE;
    if (kevent(ctx->kqfd, &kev, 1, NULL, 0, NULL) < 0)
        die("kevent");
    close(fd);
}

void
test_evfilt_read(struct test_context *ctx)
{
    create_socket_connection(&ctx->client_fd, &ctx->server_fd, ctx->iteration + 23456);

    test(kevent_socket_add, ctx);
    test(kevent_socket_del, ctx);
    test(kevent_socket_add_without_ev_add, ctx);
    test(kevent_socket_get, ctx);
    test(kevent_socket_disable_and_enable, ctx);
    test(kevent_socket_oneshot, ctx);
    test(kevent_socket_clear, ctx);
#ifdef EV_DISPATCH
    test(kevent_socket_dispatch, ctx);
#endif
    test(kevent_socket_listen_backlog, ctx);
    test(kevent_socket_eof, ctx);
    test(kevent_regular_file, ctx);
    close(ctx->client_fd);
    close(ctx->server_fd);
}