Mercurial > hg > nginx
view src/os/unix/ngx_sunpro_atomic_sparc64.h @ 7784:8cc5b0365ee5
Improved maximum errno detection.
Previously, systems without sys_nerr (or _sys_nerr) were handled with an
assumption that errors start at 0 and continuous. This is, however, not
something POSIX requires, and not true on some platforms.
Notably, on Linux, where sys_nerr is no longer available for newly linked
binaries starting with glibc 2.32, there are gaps in error list, which
used to stop us from properly detecting maximum errno. Further, on
GNU/Hurd errors start at 0x40000001.
With this change, maximum errno detection is moved to the runtime code,
now able to ignore gaps, and also detects the first error if needed.
This fixes observed "Unknown error" messages as seen on Linux with
glibc 2.32 and on GNU/Hurd.
| author | Maxim Dounin <mdounin@mdounin.ru> |
|---|---|
| date | Mon, 01 Mar 2021 20:00:43 +0300 |
| parents | d620f497c50f |
| children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #if (NGX_PTR_SIZE == 4) #define NGX_CASA ngx_casa #else #define NGX_CASA ngx_casxa #endif ngx_atomic_uint_t ngx_casa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, ngx_atomic_t *lock); ngx_atomic_uint_t ngx_casxa(ngx_atomic_uint_t set, ngx_atomic_uint_t old, ngx_atomic_t *lock); /* the code in src/os/unix/ngx_sunpro_sparc64.il */ static ngx_inline ngx_atomic_uint_t ngx_atomic_cmp_set(ngx_atomic_t *lock, ngx_atomic_uint_t old, ngx_atomic_uint_t set) { set = NGX_CASA(set, old, lock); return (set == old); } static ngx_inline ngx_atomic_int_t ngx_atomic_fetch_add(ngx_atomic_t *value, ngx_atomic_int_t add) { ngx_atomic_uint_t old, res; old = *value; for ( ;; ) { res = old + add; res = NGX_CASA(res, old, value); if (res == old) { return res; } old = res; } } #define ngx_memory_barrier() \ __asm (".volatile"); \ __asm ("membar #LoadLoad | #LoadStore | #StoreStore | #StoreLoad"); \ __asm (".nonvolatile") #define ngx_cpu_pause()