Mercurial > hg > nginx
diff src/core/ngx_output_chain.c @ 160:e7e094d34162
nginx-0.0.1-2003-10-27-11:53:49 import
author | Igor Sysoev <igor@sysoev.ru> |
---|---|
date | Mon, 27 Oct 2003 08:53:49 +0000 |
parents | |
children | 96993d4d5067 |
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new file mode 100644 --- /dev/null +++ b/src/core/ngx_output_chain.c @@ -0,0 +1,252 @@ + +#include <ngx_config.h> +#include <ngx_core.h> + + +#define NGX_NONE 1 + + +ngx_inline static int ngx_output_chain_need_to_copy(ngx_output_chain_ctx_t *ctx, + ngx_hunk_t *hunk); +static int ngx_output_chain_copy_hunk(ngx_hunk_t *dst, ngx_hunk_t *src, + int sendfile); + + +int ngx_output_chain(ngx_output_chain_ctx_t *ctx, ngx_chain_t *in) +{ + int rc, last; + ssize_t size, hsize; + ngx_chain_t *cl, *out, **last_out; + + /* + * the short path for the case when the chain ctx->in is empty + * and the incoming chain is empty too or it has the single hunk + * that does not require the copy + */ + + if (ctx->in == NULL) { + + if (in == NULL) { + return ctx->output_filter(ctx->output_ctx, in); + } + + if (!ctx->copy_chain + && in->next == NULL + && (!ngx_output_chain_need_to_copy(ctx, in->hunk))) + { + return ctx->output_filter(ctx->output_ctx, in); + } + } + + /* add the incoming hunk to the chain ctx->in */ + + if (in) { + if (ngx_chain_add_copy(ctx->pool, &ctx->in, in) == NGX_ERROR) { + return NGX_ERROR; + } + } + + last = NGX_NONE; + last_out = &out; + + for ( ;; ) { + + while (ctx->in) { + + if (!ngx_output_chain_need_to_copy(ctx, ctx->in->hunk)) { + + /* move the chain link to the chain out */ + + cl = ctx->in; + ctx->in = cl->next; + + *last_out = cl; + last_out = &cl->next; + cl->next = NULL; + + continue; + } + + if (ctx->hunk == NULL) { + + /* get the free hunk */ + + if (ctx->free) { + ctx->hunk = ctx->free->hunk; + ctx->free = ctx->free->next; + + } else if (ctx->hunks < ctx->bufs.num) { + + size = ctx->bufs.size; + + if (ctx->in->hunk->type & NGX_HUNK_LAST) { + + hsize = ngx_hunk_size(ctx->in->hunk); + + if (hsize < ctx->bufs.size) { + + /* + * allocate small temp hunk for the small last hunk + * or its small last part + */ + + size = hsize; + + } else if (ctx->bufs.num == 1 + && (hsize < ctx->bufs.size + + (ctx->bufs.size >> 2))) + { + /* + * allocate a temp hunk that equals + * to the last hunk if the last hunk size is lesser + * than 1.25 of bufs.size and a temp hunk is single + */ + + size = hsize; + } + } + + ngx_test_null(ctx->hunk, + ngx_create_temp_hunk(ctx->pool, size, 0, 0), + NGX_ERROR); + ctx->hunk->tag = ctx->tag; + ctx->hunk->type |= NGX_HUNK_RECYCLED; + ctx->hunks++; + + } else { + break; + } + } + + rc = ngx_output_chain_copy_hunk(ctx->hunk, ctx->in->hunk, + ctx->sendfile); + + if (rc == NGX_ERROR) { + return rc; + } + + if (rc == NGX_AGAIN) { + if (out) { + break; + } + return rc; + } + + /* delete the completed hunk from the chain ctx->in */ + + if (ngx_hunk_size(ctx->in->hunk) == 0) { + ctx->in = ctx->in->next; + } + + ngx_alloc_link_and_set_hunk(cl, ctx->hunk, ctx->pool, NGX_ERROR); + *last_out = cl; + last_out = &cl->next; + ctx->hunk = NULL; + + if (ctx->free == NULL) { + break; + } + } + + if (out == NULL && last != NGX_NONE) { + return last; + } + + last = ctx->output_filter(ctx->output_ctx, out); + + ngx_chain_update_chains(&ctx->free, &ctx->busy, &out, ctx->tag); + last_out = &out; + } +} + + +ngx_inline static int ngx_output_chain_need_to_copy(ngx_output_chain_ctx_t *ctx, + ngx_hunk_t *hunk) +{ + if (ngx_hunk_special(hunk)) { + return 0; + } + + if (!ctx->sendfile) { + return 1; + } + + if (ctx->need_in_memory && (!(hunk->type & NGX_HUNK_IN_MEMORY))) { + return 1; + } + + + if (ctx->need_in_temp && (hunk->type & (NGX_HUNK_MEMORY|NGX_HUNK_MMAP))) { + return 1; + } + + return 0; +} + + +static int ngx_output_chain_copy_hunk(ngx_hunk_t *dst, ngx_hunk_t *src, + int sendfile) +{ + ssize_t n, size; + + size = ngx_hunk_size(src); + + if (size > (dst->end - dst->pos)) { + size = dst->end - dst->pos; + } + + if (src->type & NGX_HUNK_IN_MEMORY) { + ngx_memcpy(dst->pos, src->pos, size); + src->pos += size; + dst->last += size; + + if (src->type & NGX_HUNK_FILE) { + src->file_pos += size; + } + + if ((src->type & NGX_HUNK_LAST) && src->pos == src->last) { + dst->type |= NGX_HUNK_LAST; + } + + } else { + n = ngx_read_file(src->file, dst->pos, size, src->file_pos); + +if (n == 0) { +ngx_log_debug(src->file->log, "READ: %qd:%qd %X:%X %X:%X" _ + src->file_pos _ src->file_last _ + dst->pos _ dst->last _ dst->start _ dst->end); +} + + if (n == NGX_ERROR) { + return n; + } + +#if (NGX_FILE_AIO_READ) + if (n == NGX_AGAIN) { + return n; + } +#endif + + if (n != size) { + ngx_log_error(NGX_LOG_ALERT, src->file->log, 0, + ngx_read_file_n " reads only %d of %d from file", + n, size); + if (n == 0) { + return NGX_ERROR; + } + } + + src->file_pos += n; + dst->last += n; + + if (!sendfile) { + dst->type &= ~NGX_HUNK_FILE; + } + + if ((src->type & NGX_HUNK_LAST) && src->file_pos == src->file_last) { + dst->type |= NGX_HUNK_LAST; + } + } + + return NGX_OK; +}