From 0bfec6cd1183f4985733e355f01f6e12df2fb2be Mon Sep 17 00:00:00 2001
From: Juha Vuolle <juha.vuolle@qt.io>
Date: Mon, 4 Dec 2023 15:04:43 +0200
Subject: [PATCH] QHttpHeaders: reserve memory for headers when creating from a
 container
MIME-Version: 1.0
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To avoid any potential resizes during append looping

Task-number: QTBUG-119002
Change-Id: I8f4c391f05b5c5bd0b48a4f17b11996652006508
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
---
 src/network/access/qhttpheaders.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/network/access/qhttpheaders.cpp b/src/network/access/qhttpheaders.cpp
index a66adf81617..de2f7e148a4 100644
--- a/src/network/access/qhttpheaders.cpp
+++ b/src/network/access/qhttpheaders.cpp
@@ -528,6 +528,7 @@ QHttpHeaders::QHttpHeaders() : d(new QHttpHeadersPrivate)
 QHttpHeaders QHttpHeaders::fromListOfPairs(const QList<std::pair<QByteArray, QByteArray>> &headers)
 {
     QHttpHeaders h;
+    h.d->headers.reserve(headers.size());
     for (const auto &header : headers)
         h.append(header.first, header.second);
     return h;
@@ -542,6 +543,7 @@ QHttpHeaders QHttpHeaders::fromListOfPairs(const QList<std::pair<QByteArray, QBy
 QHttpHeaders QHttpHeaders::fromMultiMap(const QMultiMap<QByteArray, QByteArray> &headers)
 {
     QHttpHeaders h;
+    h.d->headers.reserve(headers.size());
     for (const auto &[name,value] : headers.asKeyValueRange())
         h.append(name, value);
     return h;
@@ -556,6 +558,7 @@ QHttpHeaders QHttpHeaders::fromMultiMap(const QMultiMap<QByteArray, QByteArray>
 QHttpHeaders QHttpHeaders::fromMultiHash(const QMultiHash<QByteArray, QByteArray> &headers)
 {
     QHttpHeaders h;
+    h.d->headers.reserve(headers.size());
     for (const auto &[name,value] : headers.asKeyValueRange())
         h.append(name, value);
     return h;