nginx 1.0.9 *) Change: now the 0x7F-0x1F characters are escaped as \xXX in an access_log. *) Change: now SIGWINCH signal works only in daemon mode. *) Feature: "proxy/fastcgi/scgi/uwsgi_ignore_headers" directives support the following additional values: X-Accel-Limit-Rate, X-Accel-Buffering, X-Accel-Charset. *) Feature: decrease of memory consumption if SSL is used. *) Feature: accept filters are now supported on NetBSD. *) Feature: the "uwsgi_buffering" and "scgi_buffering" directives. Thanks to Peter Smit. *) Bugfix: a segmentation fault occurred on start or while reconfiguration if the "ssl" directive was used at http level and there was no "ssl_certificate" defined. *) Bugfix: some UTF-8 characters were processed incorrectly. Thanks to Alexey Kuts. *) Bugfix: the ngx_http_rewrite_module directives specified at "server" level were executed twice if no matching locations were defined. *) Bugfix: a socket leak might occurred if "aio sendfile" was used. *) Bugfix: connections with fast clients might be closed after send_timeout if file AIO was used. *) Bugfix: in the ngx_http_autoindex_module. *) Bugfix: the module ngx_http_mp4_module did not support seeking on 32-bit platforms. *) Bugfix: non-cacheable responses might be cached if "proxy_cache_bypass" directive was used. Thanks to John Ferlito. *) Bugfix: cached responses with an empty body were returned incorrectly; the bug had appeared in 0.8.31. *) Bugfix: 201 responses of the ngx_http_dav_module were incorrect; the bug had appeared in 0.8.32. *) Bugfix: in the "return" directive. *) Bugfix: the "ssl_verify_client", "ssl_verify_depth", and "ssl_prefer_server_ciphers" directives might work incorrectly if SNI was used.

/*
 * Copyright (C) Igor Sysoev
 */


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


/*
 * find the middle queue element if the queue has odd number of elements
 * or the first element of the queue's second part otherwise
 */

ngx_queue_t *
ngx_queue_middle(ngx_queue_t *queue)
{
    ngx_queue_t  *middle, *next;

    middle = ngx_queue_head(queue);

    if (middle == ngx_queue_last(queue)) {
        return middle;
    }

    next = ngx_queue_head(queue);

    for ( ;; ) {
        middle = ngx_queue_next(middle);

        next = ngx_queue_next(next);

        if (next == ngx_queue_last(queue)) {
            return middle;
        }

        next = ngx_queue_next(next);

        if (next == ngx_queue_last(queue)) {
            return middle;
        }
    }
}


/* the stable insertion sort */

void
ngx_queue_sort(ngx_queue_t *queue,
    ngx_int_t (*cmp)(const ngx_queue_t *, const ngx_queue_t *))
{
    ngx_queue_t  *q, *prev, *next;

    q = ngx_queue_head(queue);

    if (q == ngx_queue_last(queue)) {
        return;
    }

    for (q = ngx_queue_next(q); q != ngx_queue_sentinel(queue); q = next) {

        prev = ngx_queue_prev(q);
        next = ngx_queue_next(q);

        ngx_queue_remove(q);

        do {
            if (cmp(prev, q) <= 0) {
                break;
            }

            prev = ngx_queue_prev(prev);

        } while (prev != ngx_queue_sentinel(queue));

        ngx_queue_insert_after(prev, q);
    }
}