Mercurial > hg > nginx
view src/core/ngx_crc.h @ 9225:1c9264603adc
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.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 01 Mar 2024 05:42:12 +0300 |
parents | d620f497c50f |
children |
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/* * 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_ */