Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_sub_filter_module.c @ 4622:0dfdc3f732cb
Upstream: fixed ip_hash rebalancing with the "down" flag.
Due to weight being set to 0 for down peers, order of peers after sorting
wasn't the same as without the "down" flag (with down peers at the end),
resulting in client rebalancing for clients on other servers. The only
rebalancing which should happen after adding "down" to a server is one
for clients on the server.
The problem was introduced in r1377 (which fixed endless loop by setting
weight to 0 for down servers). The loop is no longer possible with new
smooth algorithm, so preserving original weight is safe.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 14 May 2012 09:58:07 +0000 |
parents | d620f497c50f |
children | 4a18bf1833a9 05beaa2d87b3 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_str_t match; ngx_http_complex_value_t value; ngx_hash_t types; ngx_flag_t once; ngx_array_t *types_keys; } ngx_http_sub_loc_conf_t; typedef enum { sub_start_state = 0, sub_match_state, } ngx_http_sub_state_e; typedef struct { ngx_str_t match; ngx_str_t saved; ngx_str_t looked; ngx_uint_t once; /* unsigned once:1 */ ngx_buf_t *buf; u_char *pos; u_char *copy_start; u_char *copy_end; ngx_chain_t *in; ngx_chain_t *out; ngx_chain_t **last_out; ngx_chain_t *busy; ngx_chain_t *free; ngx_str_t sub; ngx_uint_t state; } ngx_http_sub_ctx_t; static ngx_int_t ngx_http_sub_output(ngx_http_request_t *r, ngx_http_sub_ctx_t *ctx); static ngx_int_t ngx_http_sub_parse(ngx_http_request_t *r, ngx_http_sub_ctx_t *ctx); static char * ngx_http_sub_filter(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static void *ngx_http_sub_create_conf(ngx_conf_t *cf); static char *ngx_http_sub_merge_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_int_t ngx_http_sub_filter_init(ngx_conf_t *cf); static ngx_command_t ngx_http_sub_filter_commands[] = { { ngx_string("sub_filter"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2, ngx_http_sub_filter, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("sub_filter_types"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, ngx_http_types_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_sub_loc_conf_t, types_keys), &ngx_http_html_default_types[0] }, { ngx_string("sub_filter_once"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_sub_loc_conf_t, once), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_sub_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_sub_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_sub_create_conf, /* create location configuration */ ngx_http_sub_merge_conf /* merge location configuration */ }; ngx_module_t ngx_http_sub_filter_module = { NGX_MODULE_V1, &ngx_http_sub_filter_module_ctx, /* module context */ ngx_http_sub_filter_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_http_output_header_filter_pt ngx_http_next_header_filter; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_sub_header_filter(ngx_http_request_t *r) { ngx_http_sub_ctx_t *ctx; ngx_http_sub_loc_conf_t *slcf; slcf = ngx_http_get_module_loc_conf(r, ngx_http_sub_filter_module); if (slcf->match.len == 0 || r->headers_out.content_length_n == 0 || ngx_http_test_content_type(r, &slcf->types) == NULL) { return ngx_http_next_header_filter(r); } ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_sub_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ctx->saved.data = ngx_pnalloc(r->pool, slcf->match.len); if (ctx->saved.data == NULL) { return NGX_ERROR; } ctx->looked.data = ngx_pnalloc(r->pool, slcf->match.len); if (ctx->looked.data == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_sub_filter_module); ctx->match = slcf->match; ctx->last_out = &ctx->out; r->filter_need_in_memory = 1; if (r == r->main) { ngx_http_clear_content_length(r); ngx_http_clear_last_modified(r); } return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_sub_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { ngx_int_t rc; ngx_buf_t *b; ngx_chain_t *cl; ngx_http_sub_ctx_t *ctx; ngx_http_sub_loc_conf_t *slcf; ctx = ngx_http_get_module_ctx(r, ngx_http_sub_filter_module); if (ctx == NULL) { return ngx_http_next_body_filter(r, in); } if ((in == NULL && ctx->buf == NULL && ctx->in == NULL && ctx->busy == NULL)) { return ngx_http_next_body_filter(r, in); } if (ctx->once && (ctx->buf == NULL || ctx->in == NULL)) { if (ctx->busy) { if (ngx_http_sub_output(r, ctx) == NGX_ERROR) { return NGX_ERROR; } } return ngx_http_next_body_filter(r, in); } /* add the incoming chain to the chain ctx->in */ if (in) { if (ngx_chain_add_copy(r->pool, &ctx->in, in) != NGX_OK) { return NGX_ERROR; } } ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http sub filter \"%V\"", &r->uri); while (ctx->in || ctx->buf) { if (ctx->buf == NULL) { ctx->buf = ctx->in->buf; ctx->in = ctx->in->next; ctx->pos = ctx->buf->pos; } if (ctx->state == sub_start_state) { ctx->copy_start = ctx->pos; ctx->copy_end = ctx->pos; } b = NULL; while (ctx->pos < ctx->buf->last) { ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "saved: \"%V\" state: %d", &ctx->saved, ctx->state); rc = ngx_http_sub_parse(r, ctx); ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "parse: %d, looked: \"%V\" %p-%p", rc, &ctx->looked, ctx->copy_start, ctx->copy_end); if (rc == NGX_ERROR) { return rc; } if (ctx->copy_start != ctx->copy_end) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "saved: \"%V\"", &ctx->saved); if (ctx->saved.len) { if (ctx->free) { cl = ctx->free; ctx->free = ctx->free->next; b = cl->buf; ngx_memzero(b, sizeof(ngx_buf_t)); } else { b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; } b->pos = ngx_pnalloc(r->pool, ctx->saved.len); if (b->pos == NULL) { return NGX_ERROR; } ngx_memcpy(b->pos, ctx->saved.data, ctx->saved.len); b->last = b->pos + ctx->saved.len; b->memory = 1; *ctx->last_out = cl; ctx->last_out = &cl->next; ctx->saved.len = 0; } if (ctx->free) { cl = ctx->free; ctx->free = ctx->free->next; b = cl->buf; } else { b = ngx_alloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; } ngx_memcpy(b, ctx->buf, sizeof(ngx_buf_t)); b->pos = ctx->copy_start; b->last = ctx->copy_end; b->shadow = NULL; b->last_buf = 0; b->recycled = 0; if (b->in_file) { b->file_last = b->file_pos + (b->last - ctx->buf->pos); b->file_pos += b->pos - ctx->buf->pos; } cl->next = NULL; *ctx->last_out = cl; ctx->last_out = &cl->next; } if (ctx->state == sub_start_state) { ctx->copy_start = ctx->pos; ctx->copy_end = ctx->pos; } else { ctx->copy_start = NULL; ctx->copy_end = NULL; } if (rc == NGX_AGAIN) { continue; } /* rc == NGX_OK */ b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } slcf = ngx_http_get_module_loc_conf(r, ngx_http_sub_filter_module); if (ctx->sub.data == NULL) { if (ngx_http_complex_value(r, &slcf->value, &ctx->sub) != NGX_OK) { return NGX_ERROR; } } if (ctx->sub.len) { b->memory = 1; b->pos = ctx->sub.data; b->last = ctx->sub.data + ctx->sub.len; } else { b->sync = 1; } cl->buf = b; cl->next = NULL; *ctx->last_out = cl; ctx->last_out = &cl->next; ctx->once = slcf->once; continue; } if (ctx->buf->last_buf || ngx_buf_in_memory(ctx->buf)) { if (b == NULL) { if (ctx->free) { cl = ctx->free; ctx->free = ctx->free->next; b = cl->buf; ngx_memzero(b, sizeof(ngx_buf_t)); } else { b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; } b->sync = 1; cl->next = NULL; *ctx->last_out = cl; ctx->last_out = &cl->next; } b->last_buf = ctx->buf->last_buf; b->shadow = ctx->buf; b->recycled = ctx->buf->recycled; } ctx->buf = NULL; ctx->saved.len = ctx->looked.len; ngx_memcpy(ctx->saved.data, ctx->looked.data, ctx->looked.len); } if (ctx->out == NULL && ctx->busy == NULL) { return NGX_OK; } return ngx_http_sub_output(r, ctx); } static ngx_int_t ngx_http_sub_output(ngx_http_request_t *r, ngx_http_sub_ctx_t *ctx) { ngx_int_t rc; ngx_buf_t *b; ngx_chain_t *cl; #if 1 b = NULL; for (cl = ctx->out; cl; cl = cl->next) { ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "sub out: %p %p", cl->buf, cl->buf->pos); if (cl->buf == b) { ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0, "the same buf was used in sub"); ngx_debug_point(); return NGX_ERROR; } b = cl->buf; } #endif rc = ngx_http_next_body_filter(r, ctx->out); if (ctx->busy == NULL) { ctx->busy = ctx->out; } else { for (cl = ctx->busy; cl->next; cl = cl->next) { /* void */ } cl->next = ctx->out; } ctx->out = NULL; ctx->last_out = &ctx->out; while (ctx->busy) { cl = ctx->busy; b = cl->buf; if (ngx_buf_size(b) != 0) { break; } if (b->shadow) { b->shadow->pos = b->shadow->last; } ctx->busy = cl->next; if (ngx_buf_in_memory(b) || b->in_file) { /* add data bufs only to the free buf chain */ cl->next = ctx->free; ctx->free = cl; } } if (ctx->in || ctx->buf) { r->buffered |= NGX_HTTP_SUB_BUFFERED; } else { r->buffered &= ~NGX_HTTP_SUB_BUFFERED; } return rc; } static ngx_int_t ngx_http_sub_parse(ngx_http_request_t *r, ngx_http_sub_ctx_t *ctx) { u_char *p, *last, *copy_end, ch, match; size_t looked; ngx_http_sub_state_e state; if (ctx->once) { ctx->copy_start = ctx->pos; ctx->copy_end = ctx->buf->last; ctx->pos = ctx->buf->last; ctx->looked.len = 0; ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "once"); return NGX_AGAIN; } state = ctx->state; looked = ctx->looked.len; last = ctx->buf->last; copy_end = ctx->copy_end; for (p = ctx->pos; p < last; p++) { ch = *p; ch = ngx_tolower(ch); if (state == sub_start_state) { /* the tight loop */ match = ctx->match.data[0]; for ( ;; ) { if (ch == match) { copy_end = p; ctx->looked.data[0] = *p; looked = 1; state = sub_match_state; goto match_started; } if (++p == last) { break; } ch = *p; ch = ngx_tolower(ch); } ctx->state = state; ctx->pos = p; ctx->looked.len = looked; ctx->copy_end = p; if (ctx->copy_start == NULL) { ctx->copy_start = ctx->buf->pos; } return NGX_AGAIN; match_started: continue; } /* state == sub_match_state */ if (ch == ctx->match.data[looked]) { ctx->looked.data[looked] = *p; looked++; if (looked == ctx->match.len) { if ((size_t) (p - ctx->pos) < looked) { ctx->saved.len = 0; } ctx->state = sub_start_state; ctx->pos = p + 1; ctx->looked.len = 0; ctx->copy_end = copy_end; if (ctx->copy_start == NULL && copy_end) { ctx->copy_start = ctx->buf->pos; } return NGX_OK; } } else if (ch == ctx->match.data[0]) { copy_end = p; ctx->looked.data[0] = *p; looked = 1; } else { copy_end = p; looked = 0; state = sub_start_state; } } ctx->state = state; ctx->pos = p; ctx->looked.len = looked; ctx->copy_end = (state == sub_start_state) ? p : copy_end; if (ctx->copy_start == NULL && ctx->copy_end) { ctx->copy_start = ctx->buf->pos; } return NGX_AGAIN; } static char * ngx_http_sub_filter(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_sub_loc_conf_t *slcf = conf; ngx_str_t *value; ngx_http_compile_complex_value_t ccv; if (slcf->match.len) { return "is duplicate"; } value = cf->args->elts; ngx_strlow(value[1].data, value[1].data, value[1].len); slcf->match = value[1]; ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[2]; ccv.complex_value = &slcf->value; if (ngx_http_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } return NGX_CONF_OK; } static void * ngx_http_sub_create_conf(ngx_conf_t *cf) { ngx_http_sub_loc_conf_t *slcf; slcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_sub_loc_conf_t)); if (slcf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->match = { 0, NULL }; * conf->sub = { 0, NULL }; * conf->sub_lengths = NULL; * conf->sub_values = NULL; * conf->types = { NULL }; * conf->types_keys = NULL; */ slcf->once = NGX_CONF_UNSET; return slcf; } static char * ngx_http_sub_merge_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_sub_loc_conf_t *prev = parent; ngx_http_sub_loc_conf_t *conf = child; ngx_conf_merge_value(conf->once, prev->once, 1); ngx_conf_merge_str_value(conf->match, prev->match, ""); if (conf->value.value.len == 0) { conf->value = prev->value; } if (ngx_http_merge_types(cf, &conf->types_keys, &conf->types, &prev->types_keys, &prev->types, ngx_http_html_default_types) != NGX_OK) { return NGX_CONF_ERROR; } return NGX_CONF_OK; } static ngx_int_t ngx_http_sub_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_sub_header_filter; ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_sub_body_filter; return NGX_OK; }