MEDIUM: http: only allocate the temporary compression buffer when needed

Since we know when the buffer is needed, only check for its allocation
at the same place in order to avoid useless tests on the normal path.

diff --git a/src/proto_http.c b/src/proto_http.c
index 114efef89d9d96f99b2236438979f09ee5b2c53c..680e15a0eeea15081629d588ea0735d7f79c2ecb 100644 (file)
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -6179,12 +6179,6 @@ int http_response_forward_body(struct session *s, struct channel *res, int an_bi
        /* in most states, we should abort in case of early close */
        channel_auto_close(res);
 
-       /* this is the first time we need the compression buffer */
-       if (s->comp_algo != NULL && tmpbuf == NULL) {
-               if ((tmpbuf = pool_alloc2(pool2_buffer)) == NULL)
-                       goto aborted_xfer; /* no memory */
-       }
-
        if (msg->sov) {
                /* we have msg->sov which points to the first byte of message
                 * body, and res->buf.p still points to the beginning of the
@@ -6207,8 +6201,19 @@ int http_response_forward_body(struct session *s, struct channel *res, int an_bi
                }
        }
 
-       if (s->comp_algo != NULL && msg->msg_state < HTTP_MSG_TRAILERS) {
-               ret = http_compression_buffer_init(s, res->buf, tmpbuf); /* init a buffer with headers */
+       if (unlikely(s->comp_algo != NULL) && msg->msg_state < HTTP_MSG_TRAILERS) {
+               /* We need a compression buffer in the DATA state to put the
+                * output of compressed data, and in CRLF state to let the
+                * TRAILERS state finish the job of removing the trailing CRLF.
+                */
+               if (unlikely(tmpbuf == NULL)) {
+                       /* this is the first time we need the compression buffer */
+                       tmpbuf = pool_alloc2(pool2_buffer);
+                       if (tmpbuf == NULL)
+                               goto aborted_xfer; /* no memory */
+               }
+
+               ret = http_compression_buffer_init(s, res->buf, tmpbuf);
                if (ret < 0) {
                        res->flags |= CF_WAKE_WRITE;
                        goto missing_data; /* not enough spaces in buffers */