Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_split_clients_module.c @ 8509:5b0c229ba5fe quic
QUIC: fixed padding calculation.
Sometimes, QUIC packets need to be of certain (or minimal) size. This is
achieved by adding PADDING frames. It is possible, that adding padding will
affect header size, thus forcing us to recalculate padding size once more.
author | Vladimir Homutov <vl@nginx.com> |
---|---|
date | Mon, 05 Jul 2021 13:17:10 +0300 |
parents | b78cf2414fda |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { uint32_t percent; ngx_http_variable_value_t value; } ngx_http_split_clients_part_t; typedef struct { ngx_http_complex_value_t value; ngx_array_t parts; } ngx_http_split_clients_ctx_t; static char *ngx_conf_split_clients_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static char *ngx_http_split_clients(ngx_conf_t *cf, ngx_command_t *dummy, void *conf); static ngx_command_t ngx_http_split_clients_commands[] = { { ngx_string("split_clients"), NGX_HTTP_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE2, ngx_conf_split_clients_block, NGX_HTTP_MAIN_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_split_clients_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_split_clients_module = { NGX_MODULE_V1, &ngx_http_split_clients_module_ctx, /* module context */ ngx_http_split_clients_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_int_t ngx_http_split_clients_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { ngx_http_split_clients_ctx_t *ctx = (ngx_http_split_clients_ctx_t *) data; uint32_t hash; ngx_str_t val; ngx_uint_t i; ngx_http_split_clients_part_t *part; *v = ngx_http_variable_null_value; if (ngx_http_complex_value(r, &ctx->value, &val) != NGX_OK) { return NGX_OK; } hash = ngx_murmur_hash2(val.data, val.len); part = ctx->parts.elts; for (i = 0; i < ctx->parts.nelts; i++) { ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http split: %uD %uD", hash, part[i].percent); if (hash < part[i].percent || part[i].percent == 0) { *v = part[i].value; return NGX_OK; } } return NGX_OK; } static char * ngx_conf_split_clients_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { char *rv; uint32_t sum, last; ngx_str_t *value, name; ngx_uint_t i; ngx_conf_t save; ngx_http_variable_t *var; ngx_http_split_clients_ctx_t *ctx; ngx_http_split_clients_part_t *part; ngx_http_compile_complex_value_t ccv; ctx = ngx_pcalloc(cf->pool, sizeof(ngx_http_split_clients_ctx_t)); if (ctx == NULL) { return NGX_CONF_ERROR; } value = cf->args->elts; ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = &ctx->value; if (ngx_http_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } name = value[2]; if (name.data[0] != '$') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid variable name \"%V\"", &name); return NGX_CONF_ERROR; } name.len--; name.data++; var = ngx_http_add_variable(cf, &name, NGX_HTTP_VAR_CHANGEABLE); if (var == NULL) { return NGX_CONF_ERROR; } var->get_handler = ngx_http_split_clients_variable; var->data = (uintptr_t) ctx; if (ngx_array_init(&ctx->parts, cf->pool, 2, sizeof(ngx_http_split_clients_part_t)) != NGX_OK) { return NGX_CONF_ERROR; } save = *cf; cf->ctx = ctx; cf->handler = ngx_http_split_clients; cf->handler_conf = conf; rv = ngx_conf_parse(cf, NULL); *cf = save; if (rv != NGX_CONF_OK) { return rv; } sum = 0; last = 0; part = ctx->parts.elts; for (i = 0; i < ctx->parts.nelts; i++) { sum = part[i].percent ? sum + part[i].percent : 10000; if (sum > 10000) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "percent total is greater than 100%%"); return NGX_CONF_ERROR; } if (part[i].percent) { last += part[i].percent * (uint64_t) 0xffffffff / 10000; part[i].percent = last; } } return rv; } static char * ngx_http_split_clients(ngx_conf_t *cf, ngx_command_t *dummy, void *conf) { ngx_int_t n; ngx_str_t *value; ngx_http_split_clients_ctx_t *ctx; ngx_http_split_clients_part_t *part; ctx = cf->ctx; value = cf->args->elts; part = ngx_array_push(&ctx->parts); if (part == NULL) { return NGX_CONF_ERROR; } if (value[0].len == 1 && value[0].data[0] == '*') { part->percent = 0; } else { if (value[0].len == 0 || value[0].data[value[0].len - 1] != '%') { goto invalid; } n = ngx_atofp(value[0].data, value[0].len - 1, 2); if (n == NGX_ERROR || n == 0) { goto invalid; } part->percent = (uint32_t) n; } part->value.len = value[1].len; part->value.valid = 1; part->value.no_cacheable = 0; part->value.not_found = 0; part->value.data = value[1].data; return NGX_CONF_OK; invalid: ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid percent value \"%V\"", &value[0]); return NGX_CONF_ERROR; }