view src/os/unix/ngx_udp_recv.c @ 4723:68ac485abbba stable-1.2

Merge of r4654, r4672, r4684, r4685, r4692: resolver changes. *) Resolver: fixed format specification. Patch by Yichun Zhang (agentzh). *) Support for IPv6 literals and an optional port in resolver. *) Fixed crash in ngx_resolver_cleanup_tree(). If sending a DNS request fails with an error (e.g., when mistakenly trying to send it to a local IP broadcast), such a request is not deleted if there are clients waiting on it. However, it was still erroneously removed from the queue. Later ngx_resolver_cleanup_tree() attempted to remove it from the queue again that resulted in a NULL pointer dereference. *) When "resolver" is configured with a domain name, only the first resolved address was used. Now all addresses will be used. *) Fixed segfault with poll and resolver used. Poll event method needs ngx_cycle->files to work, and use of ngx_exit_cycle without files set caused null pointer dereference in resolver's cleanup on udp socket close.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 02 Jul 2012 16:23:14 +0000
parents d620f497c50f
children f01ab2dbcfdc
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>


#if (NGX_HAVE_KQUEUE)

ssize_t
ngx_udp_unix_recv(ngx_connection_t *c, u_char *buf, size_t size)
{
    ssize_t       n;
    ngx_err_t     err;
    ngx_event_t  *rev;

    rev = c->read;

    do {
        n = recv(c->fd, buf, size, 0);

        ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
                       "recv: fd:%d %d of %d", c->fd, n, size);

        if (n >= 0) {
            if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) {
                rev->available -= n;

                /*
                 * rev->available may be negative here because some additional
                 * bytes may be received between kevent() and recv()
                 */

                if (rev->available <= 0) {
                    rev->ready = 0;
                    rev->available = 0;
                }
            }

            return n;
        }

        err = ngx_socket_errno;

        if (err == NGX_EAGAIN || err == NGX_EINTR) {
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err,
                           "recv() not ready");
            n = NGX_AGAIN;

        } else {
            n = ngx_connection_error(c, err, "recv() failed");
            break;
        }

    } while (err == NGX_EINTR);

    rev->ready = 0;

    if (n == NGX_ERROR) {
        rev->error = 1;
    }

    return n;
}

#else /* ! NGX_HAVE_KQUEUE */

ssize_t
ngx_udp_unix_recv(ngx_connection_t *c, u_char *buf, size_t size)
{
    ssize_t       n;
    ngx_err_t     err;
    ngx_event_t  *rev;

    rev = c->read;

    do {
        n = recv(c->fd, buf, size, 0);

        ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
                       "recv: fd:%d %d of %d", c->fd, n, size);

        if (n >= 0) {
            return n;
        }

        err = ngx_socket_errno;

        if (err == NGX_EAGAIN || err == NGX_EINTR) {
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err,
                           "recv() not ready");
            n = NGX_AGAIN;

        } else {
            n = ngx_connection_error(c, err, "recv() failed");
            break;
        }

    } while (err == NGX_EINTR);

    rev->ready = 0;

    if (n == NGX_ERROR) {
        rev->error = 1;
    }

    return n;
}

#endif /* NGX_HAVE_KQUEUE */