From ee309bafcfae0dd93de5a49063c534461d5a2f04 Mon Sep 17 00:00:00 2001
From: Christopher Faulet <cfaulet@haproxy.com>
Date: Mon, 9 Feb 2026 11:11:41 +0100
Subject: [PATCH] MINOR: http-fetch: Use pointer to HTX DATA block when
 retrieving HTX body

In sample fetch functions retrieving the message payload (req.body,
res.body...), instead of copying the payload in a trash buffer, we know
directely return a pointer the payload in the HTX message. To do so, we must
be sure there is only one HTX DATA block. Thanks to previous patches, it is
possible. However, we must take care to perform a defragmentation if
necessary.
---
 src/http_fetch.c | 53 ++++++++++++++++++++++++++++++++++++------------
 1 file changed, 40 insertions(+), 13 deletions(-)

diff --git a/src/http_fetch.c b/src/http_fetch.c
index 1f8ff8c99..c7f0302e6 100644
--- a/src/http_fetch.c
+++ b/src/http_fetch.c
@@ -624,14 +624,17 @@ static int smp_fetch_body(const struct arg *args, struct sample *smp, const char
 	struct channel *chn = ((kw[2] == 'q') ? SMP_REQ_CHN(smp) : SMP_RES_CHN(smp));
 	struct check *check = ((kw[2] == 's') ? objt_check(smp->sess->origin) : NULL);
 	struct htx *htx = smp_prefetch_htx(smp, chn, check, 1);
-	struct buffer *temp;
+	struct buffer *chk = NULL;
+	struct ist body = IST_NULL;
 	int32_t pos;
 	int finished = 0;
 
 	if (!htx)
 		return 0;
 
-	temp = get_trash_chunk();
+	if ((htx->flags & (HTX_FL_FRAGMENTED|HTX_FL_UNORDERED)) || htx_space_wraps(htx))
+		htx_defrag(htx, NULL, 0);
+
 	for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
 		struct htx_blk *blk = htx_get_blk(htx, pos);
 		enum htx_blk_type type = htx_get_blk_type(blk);
@@ -641,14 +644,27 @@ static int smp_fetch_body(const struct arg *args, struct sample *smp, const char
 			break;
 		}
 		if (type == HTX_BLK_DATA) {
-			if (!h1_format_htx_data(htx_get_blk_value(htx, blk), temp, 0))
-				return 0;
+			if (isttest(body)) {
+				/* More than one DATA block we must use a trash */
+				if (!chk) {
+					smp->flags &= ~SMP_F_CONST;
+					chk = get_trash_chunk();
+					chunk_istcat(chk, body);
+				}
+				chunk_istcat(chk, htx_get_blk_value(htx, blk));
+				body = ist2(b_orig(chk), b_data(chk));
+			}
+			else {
+				body = htx_get_blk_value(htx, blk);
+				smp->flags |= SMP_F_CONST;
+			}
 		}
 	}
 
 	smp->data.type = SMP_T_BIN;
-	smp->data.u.str = *temp;
-	smp->flags = SMP_F_VOL_TEST;
+	smp->data.u.str.area = istptr(body);
+	smp->data.u.str.data = istlen(body);
+	smp->flags |= SMP_F_VOL_TEST;
 
 	if (!finished && (check || (chn && !channel_full(chn, global.tune.maxrewrite) &&
 				    !(chn_prod(chn)->flags & (SC_FL_EOI|SC_FL_EOS|SC_FL_ABRT_DONE)))))
@@ -2056,13 +2072,16 @@ static int smp_fetch_body_param(const struct arg *args, struct sample *smp, cons
 
 	if (!smp->ctx.a[0]) { // first call, find the query string
 		struct htx *htx = smp_prefetch_htx(smp, chn, NULL, 1);
-		struct buffer *temp;
+		struct buffer *chk = NULL;
+		struct ist body = IST_NULL;
 		int32_t pos;
 
 		if (!htx)
 			return 0;
 
-		temp   = get_trash_chunk();
+		if ((htx->flags & (HTX_FL_FRAGMENTED|HTX_FL_UNORDERED)) || htx_space_wraps(htx))
+			htx_defrag(htx, NULL, 0);
+
 		for (pos = htx_get_first(htx); pos != -1; pos = htx_get_next(htx, pos)) {
 			struct htx_blk   *blk  = htx_get_blk(htx, pos);
 			enum htx_blk_type type = htx_get_blk_type(blk);
@@ -2070,20 +2089,28 @@ static int smp_fetch_body_param(const struct arg *args, struct sample *smp, cons
 			if (type == HTX_BLK_TLR || type == HTX_BLK_EOT)
 				break;
 			if (type == HTX_BLK_DATA) {
-				if (!h1_format_htx_data(htx_get_blk_value(htx, blk), temp, 0))
-					return 0;
+				if (isttest(body)) {
+					/* More than one DATA block we must use a trash */
+					if (!chk) {
+						chk = get_trash_chunk();
+						chunk_istcat(chk, body);
+					}
+					chunk_istcat(chk, htx_get_blk_value(htx, blk));
+					body = ist2(b_orig(chk), b_data(chk));
+				}
+				else
+					body = htx_get_blk_value(htx, blk);
 			}
 		}
 
-		smp->ctx.a[0] = temp->area;
-		smp->ctx.a[1] = temp->area + temp->data;
+		smp->ctx.a[0] = istptr(body);
+		smp->ctx.a[1] = istend(body);
 
 		/* Assume that the context is filled with NULL pointer
 		 * before the first call.
 		 * smp->ctx.a[2] = NULL;
 		 * smp->ctx.a[3] = NULL;
 		 */
-
 	}
 
 	return smp_fetch_param('&', name, name_len, args, smp, kw, private, insensitive);