Upstream: fixed running posted requests (ticket #788). Previously, the upstream resolve handler always called ngx_http_run_posted_requests() to run posted requests after processing the resolver response. However, if the handler was called directly from the ngx_resolve_name() function (for example, if the resolver response was cached), running posted requests from the handler could lead to the following errors: - If the request was scheduled for termination, it could actually be terminated in the resolve handler. Upper stack frames could reference the freed request object in this case. - If a significant number of requests were posted, and for each of them the resolve handler was called directly from the ngx_resolve_name() function, posted requests could be run recursively and lead to stack overflow. Now ngx_http_run_posted_requests() is only called from asynchronously invoked resolve handlers.

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


#ifndef _NGX_CRC_H_INCLUDED_
#define _NGX_CRC_H_INCLUDED_


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


/* 32-bit crc16 */

static ngx_inline uint32_t
ngx_crc(u_char *data, size_t len)
{
    uint32_t  sum;

    for (sum = 0; len; len--) {

        /*
         * gcc 2.95.2 x86 and icc 7.1.006 compile
         * that operator into the single "rol" opcode,
         * msvc 6.0sp2 compiles it into four opcodes.
         */
        sum = sum >> 1 | sum << 31;

        sum += *data++;
    }

    return sum;
}


#endif /* _NGX_CRC_H_INCLUDED_ */