From ab7932ad04c44cd94f1d3392ca661293ac08c1cd Mon Sep 17 00:00:00 2001
From: Ivailo Monev <xakepa10@gmail.com>
Date: Mon, 3 Jun 2024 18:05:49 +0300
Subject: [PATCH] effectively revert facd387374612149bee85c0418e77cb02c595caa

Signed-off-by: Ivailo Monev <xakepa10@gmail.com>
---
 src/core/tools/qbytearray.cpp | 29 ++++++++++++++++++++++-----
 src/core/tools/qhash.cpp      | 37 +++++++++++++++++++++++++++++++++--
 src/core/tools/qhash.h        | 10 ++--------
 src/tools/moc/CMakeLists.txt  |  3 +--
 4 files changed, 62 insertions(+), 17 deletions(-)

diff --git a/src/core/tools/qbytearray.cpp b/src/core/tools/qbytearray.cpp
index e02a0d736..125d83945 100644
--- a/src/core/tools/qbytearray.cpp
+++ b/src/core/tools/qbytearray.cpp
@@ -35,7 +35,9 @@
 #include <string.h>
 #include <stdlib.h>
 
-#include <libdeflate.h>
+#ifndef QT_BOOTSTRAPPED
+#  include <libdeflate.h>
+#endif
 
 #define IS_RAW_DATA(d) ((d)->data != (d)->array)
 
@@ -296,6 +298,7 @@ QByteArray qRandomUuid()
 */
 QByteArray qCompress(const char* data, int nbytes, int compressionLevel)
 {
+#ifndef QT_BOOTSTRAPPED
     if (Q_UNLIKELY(!data)) {
         qWarning("qCompress: Data is null");
         return QByteArray();
@@ -328,6 +331,13 @@ QByteArray qCompress(const char* data, int nbytes, int compressionLevel)
 
     result.resize(compresult);
     return result;
+#else
+    Q_UNUSED(data);
+    Q_UNUSED(nbytes);
+    Q_UNUSED(compressionLevel);
+    Q_ASSERT_X(false, "qCompress", "internal error");
+    return QByteArray();
+#endif
 }
 
 /*!
@@ -354,6 +364,7 @@ QByteArray qCompress(const char* data, int nbytes, int compressionLevel)
 */
 QByteArray qUncompress(const char* data, int nbytes)
 {
+#ifndef QT_BOOTSTRAPPED
     if (Q_UNLIKELY(!data)) {
         qWarning("qUncompress: Data is null");
         return QByteArray();
@@ -402,12 +413,20 @@ QByteArray qUncompress(const char* data, int nbytes)
         }
     }
     return result;
+#else
+    Q_UNUSED(data);
+    Q_UNUSED(nbytes);
+    Q_ASSERT_X(false, "qUncompress", "internal error");
+    return QByteArray();
+#endif
 }
 
-QByteArray::Data QByteArray::shared_null = { QAtomicInt(1),
-                                             0, 0, shared_null.array, {0} };
-QByteArray::Data QByteArray::shared_empty = { QAtomicInt(1),
-                                              0, 0, shared_empty.array, {0} };
+QByteArray::Data QByteArray::shared_null = {
+    QAtomicInt(1), 0, 0, shared_null.array, {0}
+};
+QByteArray::Data QByteArray::shared_empty = {
+    QAtomicInt(1), 0, 0, shared_empty.array, {0}
+};
 
 /*!
     \class QByteArray
diff --git a/src/core/tools/qhash.cpp b/src/core/tools/qhash.cpp
index e5328c898..7f5f23963 100644
--- a/src/core/tools/qhash.cpp
+++ b/src/core/tools/qhash.cpp
@@ -23,14 +23,37 @@
 #include "qbitarray.h"
 #include "qstring.h"
 
-#include <libdeflate.h>
 #include <stdlib.h>
 
 QT_BEGIN_NAMESPACE
 
+/*
+    These functions are based on Peter J. Weinberger's hash function
+    (from the Dragon Book). The constant 24 in the original function
+    was replaced with 23 to produce fewer collisions on input such as
+    "a", "aa", "aaa", "aaaa", ...
+*/
+static inline uint hash(const QChar *p, int n)
+{
+    uint h = 0;
+    while (n--) {
+        h = (h << 4) + (*p++).unicode();
+        h ^= (h & 0xf0000000) >> 23;
+        h &= 0x0fffffff;
+    }
+    return h;
+}
+
 uint qHash(const char *key, const uint len)
 {
-    return libdeflate_crc32(0, key, len);
+    uint h = 0;
+    uint n = len;
+    while (n--) {
+        h = (h << 4) + *key++;
+        h ^= (h & 0xf0000000) >> 23;
+        h &= 0x0fffffff;
+    }
+    return h;
 }
 
 uint qHash(const QBitArray &bitArray)
@@ -38,6 +61,16 @@ uint qHash(const QBitArray &bitArray)
     return qHash(bitArray.d.constData(), bitArray.d.size());
 }
 
+uint qHash(const QString &key)
+{
+    return hash(key.unicode(), key.size());
+}
+
+uint qHash(const QStringRef &key)
+{
+    return hash(key.unicode(), key.size());
+}
+
 /*
     The prime_deltas array is a table of selected prime values, even
     though it doesn't look like one. The primes we are using are 1,
diff --git a/src/core/tools/qhash.h b/src/core/tools/qhash.h
index adeebd46c..ec1b48cfe 100644
--- a/src/core/tools/qhash.h
+++ b/src/core/tools/qhash.h
@@ -36,6 +36,8 @@ class QStringRef;
 
 Q_CORE_EXPORT uint qHash(const char *key, const uint len);
 Q_CORE_EXPORT uint qHash(const QBitArray &key);
+Q_CORE_EXPORT uint qHash(const QString &key);
+Q_CORE_EXPORT uint qHash(const QStringRef &key);
 
 inline uint qHash(const char key) { return uint(key); }
 inline uint qHash(const uchar key) { return uint(key); }
@@ -64,14 +66,6 @@ inline uint qHash(const quint64 key)
 inline uint qHash(const qint64 key) { return qHash(quint64(key)); }
 inline uint qHash(const QChar key) { return qHash(key.unicode()); }
 inline uint qHash(const QByteArray &key) { return qHash(key.constData(), key.size()); }
-inline uint qHash(const QString &key)
-{
-    return qHash(reinterpret_cast<const char *>(key.unicode()), key.size() * sizeof(QChar));
-}
-inline uint qHash(const QStringRef &key)
-{
-    return qHash(reinterpret_cast<const char *>(key.unicode()), key.size() * sizeof(QChar));
-}
 template <class T> inline uint qHash(const T *key)
 {
     return qHash(reinterpret_cast<quintptr>(key));
diff --git a/src/tools/moc/CMakeLists.txt b/src/tools/moc/CMakeLists.txt
index 1d89cb65b..15321d3eb 100644
--- a/src/tools/moc/CMakeLists.txt
+++ b/src/tools/moc/CMakeLists.txt
@@ -11,7 +11,6 @@ include_directories(
     ${CMAKE_BINARY_DIR}/include/QtCore
     ${CMAKE_CURRENT_SOURCE_DIR}
     ${ICU_INCLUDES}
-    ${DEFLATE_INCLUDES}
 )
 
 set(MOC_SOURCES
@@ -81,7 +80,7 @@ set(BOOTSTRAP_SOURCES
 
 add_executable(bootstrap_moc ${BOOTSTRAP_SOURCES} ${MOC_SOURCES})
 target_compile_definitions(bootstrap_moc PRIVATE ${BOOTSTRAP_DEFINITIONS})
-target_link_libraries(bootstrap_moc ${ICU_LIBRARIES} ${DEFLATE_LIBRARIES})
+target_link_libraries(bootstrap_moc ${ICU_LIBRARIES})
 
 add_executable(moc ${MOC_SOURCES})
 target_link_libraries(moc ${EXTRA_MOC_LIBS})