Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_chunked_filter_module.c @ 6133:af7eba90645d
Win32: shared memory base addresses and remapping.
Two mechanisms are implemented to make it possible to store pointers
in shared memory on Windows, in particular on Windows Vista and later
versions with ASLR:
- The ngx_shm_remap() function added to allow remapping of a shared memory
zone to the address originally used for it in the master process. While
important, it doesn't solve the problem by itself as in many cases it's
not possible to use the address because of conflicts with other
allocations.
- We now create mappings at the same address in all processes by starting
mappings at predefined addresses normally unused by newborn processes.
These two mechanisms combined allow to use shared memory on Windows
almost without problems, including reloads.
Based on the patch by Sergey Brester:
http://mailman.nginx.org/pipermail/nginx-devel/2015-April/006836.html
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 27 Apr 2015 18:25:42 +0300 |
parents | 7fa7e60a7f66 |
children | b1858fc47e3b |
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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_chain_t *free; ngx_chain_t *busy; } ngx_http_chunked_filter_ctx_t; static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf); static ngx_http_module_t ngx_http_chunked_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_chunked_filter_init, /* 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_chunked_filter_module = { NGX_MODULE_V1, &ngx_http_chunked_filter_module_ctx, /* module context */ NULL, /* 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_chunked_header_filter(ngx_http_request_t *r) { ngx_http_core_loc_conf_t *clcf; ngx_http_chunked_filter_ctx_t *ctx; if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED || r->headers_out.status == NGX_HTTP_NO_CONTENT || r->headers_out.status < NGX_HTTP_OK || r != r->main || (r->method & NGX_HTTP_HEAD)) { return ngx_http_next_header_filter(r); } if (r->headers_out.content_length_n == -1) { if (r->http_version < NGX_HTTP_VERSION_11) { r->keepalive = 0; } else { clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (clcf->chunked_transfer_encoding) { r->chunked = 1; ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_chunked_filter_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_chunked_filter_module); } else { r->keepalive = 0; } } } return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { u_char *chunk; off_t size; ngx_int_t rc; ngx_buf_t *b; ngx_chain_t *out, *cl, *tl, **ll; ngx_http_chunked_filter_ctx_t *ctx; if (in == NULL || !r->chunked || r->header_only) { return ngx_http_next_body_filter(r, in); } ctx = ngx_http_get_module_ctx(r, ngx_http_chunked_filter_module); out = NULL; ll = &out; size = 0; cl = in; for ( ;; ) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http chunk: %d", ngx_buf_size(cl->buf)); size += ngx_buf_size(cl->buf); if (cl->buf->flush || cl->buf->sync || ngx_buf_in_memory(cl->buf) || cl->buf->in_file) { tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = cl->buf; *ll = tl; ll = &tl->next; } if (cl->next == NULL) { break; } cl = cl->next; } if (size) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; chunk = b->start; if (chunk == NULL) { /* the "0000000000000000" is 64-bit hexadecimal string */ chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1); if (chunk == NULL) { return NGX_ERROR; } b->start = chunk; b->end = chunk + sizeof("0000000000000000" CRLF) - 1; } b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->memory = 0; b->temporary = 1; b->pos = chunk; b->last = ngx_sprintf(chunk, "%xO" CRLF, size); tl->next = out; out = tl; } if (cl->buf->last_buf) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->temporary = 0; b->memory = 1; b->last_buf = 1; b->pos = (u_char *) CRLF "0" CRLF CRLF; b->last = b->pos + 7; cl->buf->last_buf = 0; *ll = tl; if (size == 0) { b->pos += 2; } } else if (size > 0) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->temporary = 0; b->memory = 1; b->pos = (u_char *) CRLF; b->last = b->pos + 2; *ll = tl; } else { *ll = NULL; } rc = ngx_http_next_body_filter(r, out); ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out, (ngx_buf_tag_t) &ngx_http_chunked_filter_module); return rc; } static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_chunked_header_filter; ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_chunked_body_filter; return NGX_OK; }