From: Henrik Holst <henrik.holst@millistream.com>
Date: Thu, 10 Feb 2022 17:47:08 +0000 (+0100)
Subject: mprintf: remove strlen calls on empty strings in dprintf_formatf
X-Git-Tag: curl-7_82_0~90
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=186340c9cd02ae383bc6b39c353ad5317d4ee574;p=thirdparty%2Fcurl.git

mprintf: remove strlen calls on empty strings in dprintf_formatf

Turns out that in dprintf_formatf we did a strlen on empty strings, a
bit strange is how common this actually is, 24 alone when doing a simple
GET from https://curl.se

Closes #8427
---

diff --git a/lib/mprintf.c b/lib/mprintf.c
index b109379bf2..13812010b3 100644
--- a/lib/mprintf.c
+++ b/lib/mprintf.c
@@ -829,6 +829,8 @@ static int dprintf_formatf(
         }
         else if(prec != -1)
           len = (size_t)prec;
+        else if(*str == '\0')
+          len = 0;
         else
           len = strlen(str);