From: Daniel Stenberg <daniel@haxx.se>
Date: Tue, 5 Aug 2025 22:52:04 +0000 (+0200)
Subject: dynbuf: assert on curlx_dyn_addf use with just "%s"
X-Git-Tag: curl-8_16_0~239
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=bf5265ad110596c2c4acf0548d5dc9162b4ddc24;p=thirdparty%2Fcurl.git

dynbuf: assert on curlx_dyn_addf use with just "%s"

Because it is wasteful and should be done better.

Closes #18194
---

diff --git a/lib/curlx/dynbuf.c b/lib/curlx/dynbuf.c
index cd4f4635a6..447203e42a 100644
--- a/lib/curlx/dynbuf.c
+++ b/lib/curlx/dynbuf.c
@@ -231,6 +231,7 @@ CURLcode curlx_dyn_addf(struct dynbuf *s, const char *fmt, ...)
   DEBUGASSERT(s);
   DEBUGASSERT(s->init == DYNINIT);
   DEBUGASSERT(!s->leng || s->bufr);
+  DEBUGASSERT(strcmp(fmt, "%s")); /* use curlx_dyn_add instead */
   va_start(ap, fmt);
   result = curlx_dyn_vaddf(s, fmt, ap);
   va_end(ap);