Mercurial > hg > nginx
view src/core/ngx_buf.c @ 8514:52c88f41d24c quic
QUIC: handling packets with send time equal to lost send time.
Previously, such packets weren't handled as the resulting zero remaining time
prevented setting the loss detection timer, which, instead, could be disarmed.
For implementation details, see quic-recovery draft 29, appendix A.10.
author | Sergey Kandaurov <pluknet@nginx.com> |
---|---|
date | Wed, 19 Aug 2020 13:24:30 +0300 |
parents | da9941c9b01b |
children | c7a8bdf5af55 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> ngx_buf_t * ngx_create_temp_buf(ngx_pool_t *pool, size_t size) { ngx_buf_t *b; b = ngx_calloc_buf(pool); if (b == NULL) { return NULL; } b->start = ngx_palloc(pool, size); if (b->start == NULL) { return NULL; } /* * set by ngx_calloc_buf(): * * b->file_pos = 0; * b->file_last = 0; * b->file = NULL; * b->shadow = NULL; * b->tag = 0; * and flags */ b->pos = b->start; b->last = b->start; b->end = b->last + size; b->temporary = 1; return b; } ngx_chain_t * ngx_alloc_chain_link(ngx_pool_t *pool) { ngx_chain_t *cl; cl = pool->chain; if (cl) { pool->chain = cl->next; return cl; } cl = ngx_palloc(pool, sizeof(ngx_chain_t)); if (cl == NULL) { return NULL; } return cl; } ngx_chain_t * ngx_create_chain_of_bufs(ngx_pool_t *pool, ngx_bufs_t *bufs) { u_char *p; ngx_int_t i; ngx_buf_t *b; ngx_chain_t *chain, *cl, **ll; p = ngx_palloc(pool, bufs->num * bufs->size); if (p == NULL) { return NULL; } ll = &chain; for (i = 0; i < bufs->num; i++) { b = ngx_calloc_buf(pool); if (b == NULL) { return NULL; } /* * set by ngx_calloc_buf(): * * b->file_pos = 0; * b->file_last = 0; * b->file = NULL; * b->shadow = NULL; * b->tag = 0; * and flags * */ b->pos = p; b->last = p; b->temporary = 1; b->start = p; p += bufs->size; b->end = p; cl = ngx_alloc_chain_link(pool); if (cl == NULL) { return NULL; } cl->buf = b; *ll = cl; ll = &cl->next; } *ll = NULL; return chain; } ngx_int_t ngx_chain_add_copy(ngx_pool_t *pool, ngx_chain_t **chain, ngx_chain_t *in) { ngx_chain_t *cl, **ll; ll = chain; for (cl = *chain; cl; cl = cl->next) { ll = &cl->next; } while (in) { cl = ngx_alloc_chain_link(pool); if (cl == NULL) { *ll = NULL; return NGX_ERROR; } cl->buf = in->buf; *ll = cl; ll = &cl->next; in = in->next; } *ll = NULL; return NGX_OK; } ngx_chain_t * ngx_chain_get_free_buf(ngx_pool_t *p, ngx_chain_t **free) { ngx_chain_t *cl; if (*free) { cl = *free; *free = cl->next; cl->next = NULL; return cl; } cl = ngx_alloc_chain_link(p); if (cl == NULL) { return NULL; } cl->buf = ngx_calloc_buf(p); if (cl->buf == NULL) { return NULL; } cl->next = NULL; return cl; } void ngx_chain_update_chains(ngx_pool_t *p, ngx_chain_t **free, ngx_chain_t **busy, ngx_chain_t **out, ngx_buf_tag_t tag) { ngx_chain_t *cl; if (*out) { if (*busy == NULL) { *busy = *out; } else { for (cl = *busy; cl->next; cl = cl->next) { /* void */ } cl->next = *out; } *out = NULL; } while (*busy) { cl = *busy; if (ngx_buf_size(cl->buf) != 0) { break; } if (cl->buf->tag != tag) { *busy = cl->next; ngx_free_chain(p, cl); continue; } cl->buf->pos = cl->buf->start; cl->buf->last = cl->buf->start; *busy = cl->next; cl->next = *free; *free = cl; } } off_t ngx_chain_coalesce_file(ngx_chain_t **in, off_t limit) { off_t total, size, aligned, fprev; ngx_fd_t fd; ngx_chain_t *cl; total = 0; cl = *in; fd = cl->buf->file->fd; do { size = cl->buf->file_last - cl->buf->file_pos; if (size > limit - total) { size = limit - total; aligned = (cl->buf->file_pos + size + ngx_pagesize - 1) & ~((off_t) ngx_pagesize - 1); if (aligned <= cl->buf->file_last) { size = aligned - cl->buf->file_pos; } total += size; break; } total += size; fprev = cl->buf->file_pos + size; cl = cl->next; } while (cl && cl->buf->in_file && total < limit && fd == cl->buf->file->fd && fprev == cl->buf->file_pos); *in = cl; return total; } ngx_chain_t * ngx_chain_update_sent(ngx_chain_t *in, off_t sent) { off_t size; for ( /* void */ ; in; in = in->next) { if (ngx_buf_special(in->buf)) { continue; } if (sent == 0) { break; } size = ngx_buf_size(in->buf); if (sent >= size) { sent -= size; if (ngx_buf_in_memory(in->buf)) { in->buf->pos = in->buf->last; } if (in->buf->in_file) { in->buf->file_pos = in->buf->file_last; } continue; } if (ngx_buf_in_memory(in->buf)) { in->buf->pos += (size_t) sent; } if (in->buf->in_file) { in->buf->file_pos += sent; } break; } return in; }