make QMakeParser take a QStringRef as input

the only place where this actually saves a deep copy is the evaluation
of if(), but as a side effect the parser is now able to deal with not
null-terminated strings, which is kinda nice as well.

Change-Id: Ib6d08617aa79d2f9eaecd4906d4d548f34bf377d
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

qmake/library/qmakebuiltins.cpp

@@ -1210,7 +1210,8 @@ QMakeEvaluator::VisitReturn QMakeEvaluator::evaluateBuiltinConditional(
         return ReturnFalse; // Another qmake breakage
     case T_EVAL: {
             VisitReturn ret = ReturnFalse;
-            ProFile *pro = m_parser->parsedProBlock(args.join(statics.field_sep),
+            QString contents = args.join(statics.field_sep);
+            ProFile *pro = m_parser->parsedProBlock(QStringRef(&contents),
                                                     m_current.pro->fileName(), m_current.line);
             if (m_cumulative || pro->isOk()) {
                 m_locationStack.push(m_current);
@@ -1226,7 +1227,7 @@ QMakeEvaluator::VisitReturn QMakeEvaluator::evaluateBuiltinConditional(
             evalError(fL1S("if(condition) requires one argument."));
             return ReturnFalse;
         }
-        return returnBool(evaluateConditional(args.at(0).toQString(),
+        return returnBool(evaluateConditional(args.at(0).toQStringRef(),
                                               m_current.pro->fileName(), m_current.line));
     }
     case T_CONFIG: {

qmake/library/qmakeevaluator.cpp

@@ -1277,7 +1277,7 @@ void QMakeEvaluator::setupProject()
 void QMakeEvaluator::evaluateCommand(const QString &cmds, const QString &where)
 {
     if (!cmds.isEmpty()) {
-        ProFile *pro = m_parser->parsedProBlock(cmds, where, -1);
+        ProFile *pro = m_parser->parsedProBlock(QStringRef(&cmds), where, -1);
         if (pro->isOk()) {
             m_locationStack.push(m_current);
             visitProBlock(pro, pro->tokPtr());
@@ -1760,7 +1760,7 @@ ProStringList QMakeEvaluator::evaluateExpandFunction(
     return ProStringList();
 }
 
-bool QMakeEvaluator::evaluateConditional(const QString &cond, const QString &where, int line)
+bool QMakeEvaluator::evaluateConditional(const QStringRef &cond, const QString &where, int line)
 {
     bool ret = false;
     ProFile *pro = m_parser->parsedProBlock(cond, where, line, QMakeParser::TestGrammar);
@@ -1778,7 +1778,7 @@ void QMakeEvaluator::checkRequirements(const ProStringList &deps)
 {
     ProStringList &failed = valuesRef(ProKey("QMAKE_FAILED_REQUIREMENTS"));
     for (const ProString &dep : deps)
-        if (!evaluateConditional(dep.toQString(), m_current.pro->fileName(), m_current.line))
+        if (!evaluateConditional(dep.toQStringRef(), m_current.pro->fileName(), m_current.line))
             failed << dep;
 }
 #endif

qmake/library/qmakeevaluator.h

@@ -216,7 +216,7 @@ public:
     ProStringList evaluateBuiltinExpand(int func_t, const ProKey &function, const ProStringList &args);
     VisitReturn evaluateBuiltinConditional(int func_t, const ProKey &function, const ProStringList &args);
 
-    bool evaluateConditional(const QString &cond, const QString &where, int line = -1);
+    bool evaluateConditional(const QStringRef &cond, const QString &where, int line = -1);
 #ifdef PROEVALUATOR_FULL
     void checkRequirements(const ProStringList &deps);
 #endif

qmake/library/qmakeparser.cpp

@@ -224,7 +224,7 @@ ProFile *QMakeParser::parsedProFile(const QString &fileName, ParseFlags flags)
 }
 
 ProFile *QMakeParser::parsedProBlock(
-        const QString &contents, const QString &name, int line, SubGrammar grammar)
+        const QStringRef &contents, const QString &name, int line, SubGrammar grammar)
 {
     ProFile *pro = new ProFile(name);
     read(pro, contents, line, grammar);
@@ -247,7 +247,7 @@ bool QMakeParser::read(ProFile *pro, ParseFlags flags)
                                fL1S("Cannot read %1: %2").arg(pro->fileName(), errStr));
         return false;
     }
-    read(pro, content, 1, FullGrammar);
+    read(pro, QStringRef(&content), 1, FullGrammar);
     return true;
 }
 
@@ -289,7 +289,7 @@ void QMakeParser::finalizeHashStr(ushort *buf, uint len)
     buf[-2] = (ushort)(hash >> 16);
 }
 
-void QMakeParser::read(ProFile *pro, const QString &in, int line, SubGrammar grammar)
+void QMakeParser::read(ProFile *pro, const QStringRef &in, int line, SubGrammar grammar)
 {
     m_proFile = pro;
     m_lineNo = line;
@@ -334,8 +334,8 @@ void QMakeParser::read(ProFile *pro, const QString &in, int line, SubGrammar gra
     QStack<ParseCtx> xprStack;
     xprStack.reserve(10);
 
-    // We rely on QStrings being null-terminated, so don't maintain a global end pointer.
     const ushort *cur = (const ushort *)in.unicode();
+    const ushort *inend = cur + in.length();
     m_canElse = false;
   freshLine:
     m_state = StNew;
@@ -418,7 +418,7 @@ void QMakeParser::read(ProFile *pro, const QString &in, int line, SubGrammar gra
     int indent;
 
     if (context == CtxPureValue) {
-        end = (const ushort *)in.unicode() + in.length();
+        end = inend;
         cptr = 0;
         lineCont = false;
         indent = 0; // just gcc being stupid
@@ -430,24 +430,30 @@ void QMakeParser::read(ProFile *pro, const QString &in, int line, SubGrammar gra
 
         // First, skip leading whitespace
         for (indent = 0; ; ++cur, ++indent) {
+            if (cur == inend) {
+                cur = 0;
+                goto flushLine;
+            }
             c = *cur;
             if (c == '\n') {
                 ++cur;
                 goto flushLine;
-            } else if (!c) {
-                cur = 0;
-                goto flushLine;
-            } else if (c != ' ' && c != '\t' && c != '\r') {
-                break;
             }
+            if (c != ' ' && c != '\t' && c != '\r')
+                break;
         }
 
         // Then strip comments. Yep - no escaping is possible.
         for (cptr = cur;; ++cptr) {
+            if (cptr == inend) {
+                end = cptr;
+                break;
+            }
             c = *cptr;
             if (c == '#') {
-                for (end = cptr; (c = *++cptr);) {
+                end = cptr;
-                    if (c == '\n') {
+                while (++cptr < inend) {
+                    if (*cptr == '\n') {
                         ++cptr;
                         break;
                     }
@@ -460,10 +466,6 @@ void QMakeParser::read(ProFile *pro, const QString &in, int line, SubGrammar gra
                 }
                 break;
             }
-            if (!c) {
-                end = cptr;
-                break;
-            }
             if (c == '\n') {
                 end = cptr++;
                 break;
@@ -1215,7 +1217,7 @@ void QMakeParser::finalizeCall(ushort *&tokPtr, ushort *uc, ushort *ptr, int arg
 bool QMakeParser::resolveVariable(ushort *xprPtr, int tlen, int needSep, ushort **ptr,
                                   ushort **buf, QString *xprBuff,
                                   ushort **tokPtr, QString *tokBuff,
-                                  const ushort *cur, const QString &in)
+                                  const ushort *cur, const QStringRef &in)
 {
     QString out;
     m_tmp.setRawData((const QChar *)xprPtr, tlen);

qmake/library/qmakeparser.h

@@ -87,7 +87,7 @@ public:
     enum SubGrammar { FullGrammar, TestGrammar, ValueGrammar };
     // fileName is expected to be absolute and cleanPath()ed.
     ProFile *parsedProFile(const QString &fileName, ParseFlags flags = ParseDefault);
-    ProFile *parsedProBlock(const QString &contents, const QString &name, int line = 0,
+    ProFile *parsedProBlock(const QStringRef &contents, const QString &name, int line = 0,
                             SubGrammar grammar = FullGrammar);
 
     void discardFileFromCache(const QString &fileName);
@@ -130,7 +130,7 @@ private:
     };
 
     bool read(ProFile *pro, ParseFlags flags);
-    void read(ProFile *pro, const QString &content, int line, SubGrammar grammar);
+    void read(ProFile *pro, const QStringRef &content, int line, SubGrammar grammar);
 
     ALWAYS_INLINE void putTok(ushort *&tokPtr, ushort tok);
     ALWAYS_INLINE void putBlockLen(ushort *&tokPtr, uint len);
@@ -141,7 +141,7 @@ private:
     ALWAYS_INLINE bool resolveVariable(ushort *xprPtr, int tlen, int needSep, ushort **ptr,
                                        ushort **buf, QString *xprBuff,
                                        ushort **tokPtr, QString *tokBuff,
-                                       const ushort *cur, const QString &in);
+                                       const ushort *cur, const QStringRef &in);
     void finalizeCond(ushort *&tokPtr, ushort *uc, ushort *ptr, int wordCount);
     void finalizeCall(ushort *&tokPtr, ushort *uc, ushort *ptr, int argc);
     void warnOperator(const char *msg);

qmake/project.cpp

@@ -120,7 +120,8 @@ QStringList QMakeProject::expand(const ProKey &func, const QList<ProStringList>
 ProString QMakeProject::expand(const QString &expr, const QString &where, int line)
 {
     ProString ret;
-    ProFile *pro = m_parser->parsedProBlock(expr, where, line, QMakeParser::ValueGrammar);
+    ProFile *pro = m_parser->parsedProBlock(QStringRef(&expr), where, line,
+                                            QMakeParser::ValueGrammar);
     if (pro->isOk()) {
         m_current.pro = pro;
         m_current.line = 0;

qmake/project.h

@@ -55,7 +55,7 @@ public:
     ProString expand(const QString &v, const QString &file, int line);
     QStringList expand(const ProKey &func, const QList<ProStringList> &args);
     bool test(const QString &v, const QString &file, int line)
-        { m_current.clear(); return evaluateConditional(v, file, line); }
+        { m_current.clear(); return evaluateConditional(QStringRef(&v), file, line); }
     bool test(const ProKey &func, const QList<ProStringList> &args);
 
     bool isSet(const ProKey &v) const { return m_valuemapStack.first().contains(v); }

tests/auto/tools/qmakelib/evaltest.cpp

@@ -2477,12 +2477,12 @@ void tst_qmakelib::proEval()
     globals.environment = m_env;
     globals.setProperties(m_prop);
     globals.setDirectories(m_indir, m_outdir);
-    ProFile *outPro = parser.parsedProBlock(out, "out", 1, QMakeParser::FullGrammar);
+    ProFile *outPro = parser.parsedProBlock(QStringRef(&out), "out", 1, QMakeParser::FullGrammar);
     if (!outPro->isOk()) {
         qWarning("Expected output is malformed");
         verified = false;
     }
-    ProFile *pro = parser.parsedProBlock(in, infile, 1, QMakeParser::FullGrammar);
+    ProFile *pro = parser.parsedProBlock(QStringRef(&in), infile, 1, QMakeParser::FullGrammar);
     QMakeEvaluator visitor(&globals, &parser, &vfs, &handler);
     visitor.setOutputDir(m_outdir);
 #ifdef Q_OS_WIN

tests/auto/tools/qmakelib/parsertest.cpp

@@ -1955,7 +1955,7 @@ void tst_qmakelib::proParser()
     handler.setExpectedMessages(msgs.split('\n', QString::SkipEmptyParts));
     QMakeVfs vfs;
     QMakeParser parser(0, &vfs, &handler);
-    ProFile *pro = parser.parsedProBlock(in, "in", 1, QMakeParser::FullGrammar);
+    ProFile *pro = parser.parsedProBlock(QStringRef(&in), "in", 1, QMakeParser::FullGrammar);
     if (handler.printedMessages()) {
         qWarning("Got unexpected message(s)");
         verified = false;