Syslog: introduced ngx_syslog_send() error logging moderation. Errors when logging to syslog are now logged at most once per second. This ensures that persistent errors won't flood other logs, and spontaneous errors, such as ENOBUFS as observed on BSD systems when syslogd cannot cope with load, or EAGAIN as seen in similar situation on Linux, won't further overload logging subsystem, leading to more errors. Further, errors now can only trigger reconnects at most once per second. This ensures that persistent errors, which cannot be fixed with reconnects, don't trigger too much unneeded work. Additionally, in case of connection errors, such as when syslogd is not running, connection attempts are only made once per second.

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


#ifndef _NGX_SHA1_H_INCLUDED_
#define _NGX_SHA1_H_INCLUDED_


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


typedef struct {
    uint64_t  bytes;
    uint32_t  a, b, c, d, e, f;
    u_char    buffer[64];
} ngx_sha1_t;


void ngx_sha1_init(ngx_sha1_t *ctx);
void ngx_sha1_update(ngx_sha1_t *ctx, const void *data, size_t size);
void ngx_sha1_final(u_char result[20], ngx_sha1_t *ctx);


#endif /* _NGX_SHA1_H_INCLUDED_ */