Mercurial > hg > nginx
view src/core/ngx_queue.h @ 4576:876e6b0814a5
Fixed signed integer overflows in timer code (ticket #145).
Integer overflow is undefined behaviour in C and this indeed caused
problems on Solaris/SPARC (at least in some cases). Fix is to
subtract unsigned integers instead, and then cast result to a signed
one, which is implementation-defined behaviour and used to work.
Strictly speaking, we should compare (unsigned) result with the maximum
value of the corresponding signed integer type instead, this will be
defined behaviour. This will require much more changes though, and
considered to be overkill for now.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Fri, 06 Apr 2012 23:46:09 +0000 |
parents | d620f497c50f |
children | 3038bd4d7816 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #ifndef _NGX_QUEUE_H_INCLUDED_ #define _NGX_QUEUE_H_INCLUDED_ typedef struct ngx_queue_s ngx_queue_t; struct ngx_queue_s { ngx_queue_t *prev; ngx_queue_t *next; }; #define ngx_queue_init(q) \ (q)->prev = q; \ (q)->next = q #define ngx_queue_empty(h) \ (h == (h)->prev) #define ngx_queue_insert_head(h, x) \ (x)->next = (h)->next; \ (x)->next->prev = x; \ (x)->prev = h; \ (h)->next = x #define ngx_queue_insert_after ngx_queue_insert_head #define ngx_queue_insert_tail(h, x) \ (x)->prev = (h)->prev; \ (x)->prev->next = x; \ (x)->next = h; \ (h)->prev = x #define ngx_queue_head(h) \ (h)->next #define ngx_queue_last(h) \ (h)->prev #define ngx_queue_sentinel(h) \ (h) #define ngx_queue_next(q) \ (q)->next #define ngx_queue_prev(q) \ (q)->prev #if (NGX_DEBUG) #define ngx_queue_remove(x) \ (x)->next->prev = (x)->prev; \ (x)->prev->next = (x)->next; \ (x)->prev = NULL; \ (x)->next = NULL #else #define ngx_queue_remove(x) \ (x)->next->prev = (x)->prev; \ (x)->prev->next = (x)->next #endif #define ngx_queue_split(h, q, n) \ (n)->prev = (h)->prev; \ (n)->prev->next = n; \ (n)->next = q; \ (h)->prev = (q)->prev; \ (h)->prev->next = h; \ (q)->prev = n; #define ngx_queue_add(h, n) \ (h)->prev->next = (n)->next; \ (n)->next->prev = (h)->prev; \ (h)->prev = (n)->prev; \ (h)->prev->next = h; #define ngx_queue_data(q, type, link) \ (type *) ((u_char *) q - offsetof(type, link)) ngx_queue_t *ngx_queue_middle(ngx_queue_t *queue); void ngx_queue_sort(ngx_queue_t *queue, ngx_int_t (*cmp)(const ngx_queue_t *, const ngx_queue_t *)); #endif /* _NGX_QUEUE_H_INCLUDED_ */