static ngx_int_t
ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
{
ngx_int_t rc;
ngx_connection_t *c;
ngx_output_chain_ctx_t *ctx;
ngx_http_core_loc_conf_t *clcf;
ngx_http_copy_filter_conf_t *conf;
c = r->connection;
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter: \"%V?%V\"", &r->uri, &r->args);
ctx = ngx_http_get_module_ctx(r, ngx_http_copy_filter_module);
if (ctx == NULL) {
ctx = ngx_pcalloc(r->pool, sizeof(ngx_output_chain_ctx_t));
if (ctx == NULL) {
return NGX_ERROR;
}
ngx_http_set_ctx(r, ctx, ngx_http_copy_filter_module);
conf = ngx_http_get_module_loc_conf(r, ngx_http_copy_filter_module);
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
ctx->sendfile = c->sendfile;
ctx->need_in_memory = r->main_filter_need_in_memory
|| r->filter_need_in_memory;
ctx->need_in_temp = r->filter_need_temporary;
ctx->alignment = clcf->directio_alignment;
ctx->pool = r->pool;
ctx->bufs = conf->bufs;
ctx->tag = (ngx_buf_tag_t) &ngx_http_copy_filter_module;
ctx->output_filter = (ngx_output_chain_filter_pt) ngx_http_next_filter;
ctx->filter_ctx = r;
#if (NGX_HAVE_FILE_AIO)
if (ngx_file_aio && clcf->aio) {
ctx->aio_handler = ngx_http_copy_aio_handler;
#if (NGX_HAVE_AIO_SENDFILE)
c->aio_sendfile = (clcf->aio == NGX_HTTP_AIO_SENDFILE);
#endif
}
#endif
r->request_output = 1;
}
#if (NGX_HAVE_FILE_AIO)
ctx->aio = r->aio;
#endif
for ( ;; ) {
rc = ngx_output_chain(ctx, in);
if (ctx->in == NULL) {
r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
} else {
r->buffered |= NGX_HTTP_COPY_BUFFERED;
}
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args);
#if (NGX_HAVE_FILE_AIO && NGX_HAVE_AIO_SENDFILE)
if (c->busy_sendfile) {
ssize_t n;
off_t offset;
ngx_file_t *file;
ngx_http_ephemeral_t *e;
file = c->busy_sendfile->file;
offset = c->busy_sendfile->file_pos;
if (file->aio) {
c->aio_sendfile = (offset != file->aio->last_offset);
file->aio->last_offset = offset;
if (c->aio_sendfile == 0) {
ngx_log_error(NGX_LOG_ALERT, c->log, 0,
"sendfile(%V) returned busy again",
&file->name);
}
}
c->busy_sendfile = NULL;
e = (ngx_http_ephemeral_t *) &r->uri_start;
n = ngx_file_aio_read(file, &e->aio_preload, 1, offset, r->pool);
if (n > 0) {
in = NULL;
continue;
}
rc = n;
if (file->aio) {
file->aio->data = r;
file->aio->handler = ngx_http_copy_aio_sendfile_event_handler;
r->main->blocked++;
r->aio = 1;
}
}
#endif
return rc;
}
}
static ngx_int_t
ngx_http_upstream_send_request_body(ngx_http_request_t *r,
ngx_http_upstream_t *u)
{
ngx_int_t rc;
ngx_chain_t *cl;
ajp_msg_t *msg, local_msg;
ngx_connection_t *c;
ngx_http_ajp_ctx_t *a;
ngx_http_ajp_loc_conf_t *alcf;
c = u->peer.connection;
a = ngx_http_get_module_ctx(r, ngx_http_ajp_module);
alcf = ngx_http_get_module_loc_conf(r, ngx_http_ajp_module);
if (a->state > ngx_http_ajp_st_request_body_data_sending) {
ngx_log_error(NGX_LOG_WARN, r->connection->log, 0,
"ngx_http_upstream_send_request_body: bad state(%d)",
a->state);
}
cl = ajp_data_msg_send_body(r, alcf->max_ajp_data_packet_size_conf,
&a->body);
if (u->output.in == NULL && u->output.busy == NULL) {
if (cl == NULL) {
/* If there is no more data in the body (i.e. the servlet
* container is trying to read past the end of the body),
* the server will send back an "empty" packet, which is
* a body packet with a payload length of 0.
* (0x12,0x34,0x00,0x00)
*/
msg = ajp_msg_reuse(&local_msg);
if (ajp_alloc_data_msg(r->pool, msg) != NGX_OK) {
return NGX_ERROR;
}
ajp_data_msg_end(msg, 0);
cl = ngx_alloc_chain_link(r->pool);
if (cl == NULL) {
return NGX_ERROR;
}
cl->buf = msg->buf;
cl->next = NULL;
}
}
if (a->body) {
a->state = ngx_http_ajp_st_request_body_data_sending;
} else {
a->state = ngx_http_ajp_st_request_send_all_done;
}
c->log->action = "sending request body again to upstream";
rc = ngx_output_chain(&u->output, cl);
if (rc == NGX_ERROR) {
return NGX_ERROR;
}
if (c->write->timer_set) {
ngx_del_timer(c->write);
}
if (rc == NGX_AGAIN) {
ngx_add_timer(c->write, u->conf->send_timeout);
if (ngx_handle_write_event(c->write, u->conf->send_lowat) != NGX_OK) {
return NGX_ERROR;
}
u->write_event_handler = ngx_http_upstream_send_request_body_handler;
return NGX_AGAIN;
}
/* rc == NGX_OK */
if (c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
if (ngx_tcp_push(c->fd) == NGX_ERROR) {
ngx_log_error(NGX_LOG_CRIT, c->log, ngx_socket_errno,
ngx_tcp_push_n " failed");
return NGX_ERROR;
}
c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
}
ngx_add_timer(c->read, u->conf->read_timeout);
if (ngx_handle_write_event(c->write, 0) != NGX_OK) {
return NGX_ERROR;
}
u->write_event_handler = ngx_http_upstream_dummy_handler;
return NGX_OK;
}
static ngx_int_t
ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
{
ngx_int_t rc;
ngx_connection_t *c;
ngx_output_chain_ctx_t *ctx;
ngx_http_copy_filter_conf_t *conf;
c = r->connection;
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
"copy filter: \"%V?%V\"", &r->uri, &r->args);
ctx = ngx_http_get_module_ctx(r, ngx_http_copy_filter_module);
if (ctx == NULL) {
conf = ngx_http_get_module_loc_conf(r, ngx_http_copy_filter_module);
ctx = ngx_pcalloc(r->pool, sizeof(ngx_output_chain_ctx_t));
if (ctx == NULL) {
return NGX_ERROR;
}
ngx_http_set_ctx(r, ctx, ngx_http_copy_filter_module);
ctx->sendfile = c->sendfile;
ctx->need_in_memory = r->main_filter_need_in_memory
|| r->filter_need_in_memory;
ctx->need_in_temp = r->filter_need_temporary;
ctx->pool = r->pool;
ctx->bufs = conf->bufs;
ctx->tag = (ngx_buf_tag_t) &ngx_http_copy_filter_module;
ctx->output_filter = (ngx_output_chain_filter_pt) ngx_http_next_filter;
ctx->filter_ctx = r;
r->request_output = 1;
}
rc = ngx_output_chain(ctx, in);
if (!c->destroyed) {
if (ctx->in == NULL) {
r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
} else {
r->buffered |= NGX_HTTP_COPY_BUFFERED;
}
if (r != r->main) {
r->out = ctx->in;
}
#if (NGX_DEBUG)
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args);
#endif
}
return rc;
}
static ngx_int_t
ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
{
ngx_int_t rc;
ngx_connection_t *c;
ngx_output_chain_ctx_t *ctx;
ngx_http_core_loc_conf_t *clcf;
ngx_http_copy_filter_conf_t *conf;
c = r->connection;
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter: \"%V?%V\"", &r->uri, &r->args);
ctx = ngx_http_get_module_ctx(r, ngx_http_copy_filter_module);
if (ctx == NULL) {
ctx = ngx_pcalloc(r->pool, sizeof(ngx_output_chain_ctx_t));
if (ctx == NULL) {
return NGX_ERROR;
}
ngx_http_set_ctx(r, ctx, ngx_http_copy_filter_module);
conf = ngx_http_get_module_loc_conf(r, ngx_http_copy_filter_module);
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
ctx->sendfile = c->sendfile;
ctx->need_in_memory = r->main_filter_need_in_memory
|| r->filter_need_in_memory;
ctx->need_in_temp = r->filter_need_temporary;
ctx->alignment = clcf->directio_alignment;
ctx->pool = r->pool;
ctx->bufs = conf->bufs;
ctx->tag = (ngx_buf_tag_t) &ngx_http_copy_filter_module;
ctx->output_filter = (ngx_output_chain_filter_pt)
ngx_http_next_body_filter;
ctx->filter_ctx = r;
#if (NGX_HAVE_FILE_AIO)
if (ngx_file_aio && clcf->aio == NGX_HTTP_AIO_ON) {
ctx->aio_handler = ngx_http_copy_aio_handler;
#if (NGX_HAVE_AIO_SENDFILE)
ctx->aio_preload = ngx_http_copy_aio_sendfile_preload;
#endif
}
#endif
#if (NGX_THREADS)
if (clcf->aio == NGX_HTTP_AIO_THREADS) {
ctx->thread_handler = ngx_http_copy_thread_handler;
}
#endif
if (in && in->buf && ngx_buf_size(in->buf)) {
r->request_output = 1;
}
}
#if (NGX_HAVE_FILE_AIO || NGX_THREADS)
ctx->aio = r->aio;
#endif
rc = ngx_output_chain(ctx, in);
if (ctx->in == NULL) {
r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
} else {
r->buffered |= NGX_HTTP_COPY_BUFFERED;
}
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter: %i \"%V?%V\"", rc, &r->uri, &r->args);
return rc;
}
//in为需要发送的chain链，上面存储的是实际要发送的数据
static ngx_int_t
ngx_http_copy_filter(ngx_http_request_t *r, ngx_chain_t *in)
{ //实际上在接受完后端数据后，在想客户端发送包体部分的时候，会两次调用该函数，一次是ngx_event_pipe_write_to_downstream-> p->output_filter(),
//另一次是ngx_http_upstream_finalize_request->ngx_http_send_special,可以参考上面的日志打印注释
ngx_int_t rc;
ngx_connection_t *c;
ngx_output_chain_ctx_t *ctx;
ngx_http_core_loc_conf_t *clcf;
ngx_http_copy_filter_conf_t *conf;
int aio = r->aio;
c = r->connection;
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter: \"%V?%V\", r->aio:%d", &r->uri, &r->args, aio);
ctx = ngx_http_get_module_ctx(r, ngx_http_copy_filter_module);
if (ctx == NULL) {
ctx = ngx_pcalloc(r->pool, sizeof(ngx_output_chain_ctx_t));
if (ctx == NULL) {
return NGX_ERROR;
}
ngx_http_set_ctx(r, ctx, ngx_http_copy_filter_module);
conf = ngx_http_get_module_loc_conf(r, ngx_http_copy_filter_module);
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
/*
和后端的ngx_connection_t在ngx_event_connect_peer这里置为1，但在ngx_http_upstream_connect中c->sendfile &= r->connection->sendfile;，
和客户端浏览器的ngx_connextion_t的sendfile需要在ngx_http_update_location_config中判断，因此最终是由是否在configure的时候是否有加
sendfile选项来决定是置1还是置0
*/
ctx->sendfile = c->sendfile;
ctx->need_in_memory = r->main_filter_need_in_memory
|| r->filter_need_in_memory;
ctx->need_in_temp = r->filter_need_temporary;
ctx->alignment = clcf->directio_alignment;
ctx->pool = r->pool;
ctx->bufs = conf->bufs; // 默认值output_buffers 1 32768
ctx->tag = (ngx_buf_tag_t) &ngx_http_copy_filter_module;
ctx->output_filter = (ngx_output_chain_filter_pt)
ngx_http_next_body_filter;
ctx->filter_ctx = r;
#if (NGX_HAVE_FILE_AIO)
if (ngx_file_aio && clcf->aio == NGX_HTTP_AIO_ON) { //./configure的时候加上--with-file-aio并且配置文件中aio on的时候才有效
ctx->aio_handler = ngx_http_copy_aio_handler;
#if (NGX_HAVE_AIO_SENDFILE) //只有freebsd系统才有效 auto/os/freebsd: have=NGX_HAVE_AIO_SENDFILE . auto/have
ctx->aio_preload = ngx_http_copy_aio_sendfile_preload;
#endif
}
#endif
#if (NGX_THREADS)
if (clcf->aio == NGX_HTTP_AIO_THREADS) {
//ngx_output_chain_as_is中赋值给buf->file->thread_handler
ctx->thread_handler = ngx_http_copy_thread_handler;
}
#endif
//一般在调用filter函数的源头，会在in中指定需要发送的数据长度，可以参考ngx_http_cache_send
if (in && in->buf && ngx_buf_size(in->buf)) { //判断in链中是否有数据
r->request_output = 1;
}
}
#if (NGX_HAVE_FILE_AIO || NGX_THREADS)
//实际上在接受完后端数据后，在想客户端发送包体部分的时候，会两次调用该函数，一次是ngx_event_pipe_write_to_downstream-> p->output_filter(),
//另一次是ngx_http_upstream_finalize_request->ngx_http_send_special,
//如果是aio方式，则第一次该值为0，但是第二次从ngx_http_send_special走到这里的时候已经在ngx_output_chain->ngx_file_aio_read->ngx_http_copy_aio_handler置1
//aio方式，当aio读事件完成，会通过ngx_http_copy_aio_event_handler->ngx_http_writer再次走到这里，这时候ngx_http_copy_aio_event_handler已经把r->aio置0
//可以参考上面的日志备注信息
ctx->aio = r->aio;
#endif
rc = ngx_output_chain(ctx, in);//aio on | thread_pool，这里肯定返回NGX_AGAIN,因为他们是由对应的epoll触发读取数据完毕，然后发送。
//sendfile或者内存数据这里返回NGX_OK，通过后面的ngx_linux_sendfile_chain->(ngx_linux_sendfile,ngx_writev)把数据发送出去
if (ctx->in == NULL) {
r->buffered &= ~NGX_HTTP_COPY_BUFFERED;
} else {//说明还有数据未发送到客户端r
//ngx_http_finalize_request->ngx_http_set_write_handler->ngx_http_writer通过这种方式把未发送完毕的响应报文发送出去
r->buffered |= NGX_HTTP_COPY_BUFFERED; //说明ctx->in上还有未发送的数据，函数参数in中指向在ngx_output_chain中已经赋值给了ctx->in
}
ngx_int_t buffered = r->buffered;
ngx_log_debug4(NGX_LOG_DEBUG_HTTP, c->log, 0,
"http copy filter rc: %i, buffered:%i \"%V?%V\"", rc, buffered, &r->uri, &r->args);
return rc;
}
