From dd1fbd4c0188d60c6d04e1729bae885bae598437 Mon Sep 17 00:00:00 2001
From: Ivailo Monev <xakepa10@laimg.moc>
Date: Thu, 4 Jul 2019 22:36:30 +0000
Subject: [PATCH] optimize Xlfd encoding table lookup

Signed-off-by: Ivailo Monev <xakepa10@laimg.moc>
---
 src/gui/text/qfontdatabase_x11.h | 26 +++++++++++---------------
 util/unicode/x11/makeencodings   | 10 ++++++----
 2 files changed, 17 insertions(+), 19 deletions(-)

diff --git a/src/gui/text/qfontdatabase_x11.h b/src/gui/text/qfontdatabase_x11.h
index 47309103a..d60189dab 100644
--- a/src/gui/text/qfontdatabase_x11.h
+++ b/src/gui/text/qfontdatabase_x11.h
@@ -86,13 +86,11 @@ static inline void capitalize (char *s)
 */
 // ----- begin of generated code -----
 
-struct XlfdEncoding {
+static const struct XlfdTblData {
     const char *name;
-    int id;
-    int mib;
-};
-
-static const XlfdEncoding xlfd_encoding[] = {
+    const int id;
+    const int mib;
+} XlfdTbl[] = {
     { "iso8859-1", 0, 4 },
     { "iso8859-2", 1, 5 },
     { "iso8859-3", 2, 6 },
@@ -129,21 +127,19 @@ static const XlfdEncoding xlfd_encoding[] = {
     { "unicode-*", 33, 0 },
     { "*-symbol", 34, 0 },
     { "*-fontspecific", 35, 0 },
-    { "fontspecific-*", 36, 0 },
-    { 0, 0, 0 }
+    { "fontspecific-*", 36, 0 }
 };
 
 // ----- end of generated code -----
 
 
-const int numEncodings = sizeof(xlfd_encoding) / sizeof(XlfdEncoding) - 1;
+const qint16 XlfdTblSize = sizeof(XlfdTbl) / sizeof(XlfdTblData);
 
 int qt_encoding_id_for_mib(int mib)
 {
-    const XlfdEncoding *enc = xlfd_encoding;
-    for (; enc->name; ++enc) {
-        if (enc->mib == mib)
-            return enc->id;
+    for (qint16 i = 0; i < XlfdTblSize; i++) {
+        if (XlfdTbl[i].mib == mib)
+            return XlfdTbl[i].id;
     }
     return -1;
 }
@@ -154,9 +150,9 @@ static const char * xlfd_for_id(int id)
 {
     // special case: -1 returns the "*-*" encoding, allowing us to do full
     // database population in a single X server round trip.
-    if (id < 0 || id > numEncodings)
+    if (id < 0 || id > XlfdTblSize)
         return "*-*";
-    return xlfd_encoding[id].name;
+    return XlfdTbl[i].name;
 }
 #endif
 
diff --git a/util/unicode/x11/makeencodings b/util/unicode/x11/makeencodings
index b273222bb..d8caa6a6b 100755
--- a/util/unicode/x11/makeencodings
+++ b/util/unicode/x11/makeencodings
@@ -73,14 +73,16 @@ while (<IN>) {
 
 }
 
-print out "struct XlfdEncoding {\n    const char *name;\n    int id;\n    int mib;\n};\n\n";
-
-print out "static const XlfdEncoding xlfd_encoding[] = {\n";
+print out "static const struct XlfdTblData {
+    const char *name;
+    const int id;
+    const int mib;
+} XlfdTbl[] = {\n";
 $i = 0;
 while( $i < $num ) {
   print out "    { \"".$xlfd[$i]."\", ".$i.", ".$mib[$i]." },\n";
   $i = $i + 1;
 }
-print out "    { 0, 0, 0 }\n};\n\n";
+print out "};\n\n";
 
 close out;