Umbau auf modernes C++

2 files changed, 88 insertions, 54 deletions

diff --git a/src/xml.cpp b/src/xml.cpp
index 44b423a..451ee18 100644
--- a/src/xml.cpp
+++ b/src/xml.cpp
@@ -1,18 +1,19 @@
 // Standard C++

+#include <array>

 #include <memory>

 #include <sstream>

+#include <span>

 

-// Projekt

+// Project

 #include "xml.hpp"

 

 // Expat XML Parser

-#define XML_STATIC              // force static linkage

 #include "expat.h"

 

 using namespace std;

 

 void

-XML::parse(istream& in)

+XML::parse(istream& ins)

 {

         unique_ptr<XML_ParserStruct, decltype(&XML_ParserFree)> parser(XML_ParserCreate(nullptr), XML_ParserFree);

 

@@ -22,54 +23,57 @@ XML::parse(istream& in)
         XML_SetCdataSectionHandler(parser.get(), cdata_start, cdata_end);

         XML_SetCharacterDataHandler(parser.get(), data);

 

-        char buffer[2048];

-        for ( bool done = false; !done ; ) {

-                in.read(buffer, sizeof buffer);

-                done = (in.gcount() < sizeof buffer);

+        static const auto buffer_size = 2048;

 

-                if ( XML_Parse(parser.get(), buffer, static_cast<int>(in.gcount()), done) != XML_STATUS_OK ) {

+        array<char, buffer_size> buffer{};

+

+        for ( bool done = false; !done; ) {

+                ins.read(buffer.data(), buffer_size);

+                done = ins.gcount() < buffer_size;

+

+                if ( XML_Parse(parser.get(), buffer.data(), static_cast<int>(ins.gcount()), static_cast<int>(done)) != XML_STATUS_OK ) {

                         stringstream msg;

 

                         msg << XML_ErrorString(XML_GetErrorCode(parser.get()));

                         msg << " in line " << XML_GetCurrentLineNumber(parser.get());

 

-                        throw runtime_error( msg.str() );

+                        throw runtime_error(msg.str());

                 }

         }

 }

 

 void

-XML::tag_start(void* me, const char* name, const char* attr[])

+XML::tag_start(void* self, const char* name, const char** attr)

 {

-        vector<pair<string, string>> attr_temp;

+        vector<tuple<string_view, string_view>> attr_temp;

 

-        for ( size_t i = 0; attr[i]; i += 2 )

-                attr_temp.push_back( make_pair<string, string>(attr[i], attr[i+1]) );

+        for ( auto i = 0; attr[i] != nullptr; i += 2 ) {

+                attr_temp.emplace_back(attr[i], attr[i + 1]);

+        }

 

-        reinterpret_cast<XML*>(me)->handle_start(name, attr_temp);

+        static_cast<XML*>(self)->handle_start(name, attr_temp);

 }

 

 void

-XML::tag_end(void* me, const char* name)

+XML::tag_end(void* self, const char* name)

 {

-        reinterpret_cast<XML*>(me)->handle_end(name);

+        static_cast<XML*>(self)->handle_end(name);

 }

 

 void

-XML::cdata_start(void* me)

+XML::cdata_start(void* self)

 {

-        reinterpret_cast<XML*>(me)->handle_cdata_start();

+        static_cast<XML*>(self)->handle_cdata_start();

 }

 

 void

-XML::cdata_end(void* me)

+XML::cdata_end(void* self)

 {

-        reinterpret_cast<XML*>(me)->handle_cdata_end();

+        static_cast<XML*>(self)->handle_cdata_end();

 }

 

 void

-XML::data(void* me, const char* dat, int len)

+XML::data(void* self, const char* dat, int len)

 {

-        reinterpret_cast<XML*>(me)->handle_data(vector<char>(dat, dat+len));

+        static_cast<XML*>(self)->handle_character_data({ dat, dat + len });

 }

-

diff --git a/src/xml_test.cpp b/src/xml_test.cpp
index 0af5b51..0b978a9 100644
--- a/src/xml_test.cpp
+++ b/src/xml_test.cpp
@@ -1,48 +1,78 @@
 #include <iostream>

 #include <string>

+#include <tuple>

 using namespace std;

 

 #include "xml.hpp"

 

 class MyXML : public XML {

-        public:

-                explicit MyXML(ostream& out, size_t indent = 4)

-                        : pout_(&out)

-                        , depth_(0)

-                        , indent_(indent)

-                {

-                }

+public:

+        explicit MyXML(ostream& out, size_t indent = 4)

+            : pout_(&out)

+            , indent_(indent)

+        {

+        }

 

-        protected:

-                void handle_start(const string& name, const vector<pair<string, string>>& attr)

-                {

-                        *pout_ << string(depth_++ * indent_, ' ')

-                               << "<" << name;

+protected:

+        void handle_start(string_view name, const vector<tuple<string_view, string_view>>& attr) override

+        {

+                *pout_ << string(depth_++ * indent_, ' ')

+                       << "<" << name;

 

-                        auto it = cbegin(attr);

-                        auto end = cend(attr);

-                        if ( it != end ) {

-                                *pout_ << " " << it->first << "=\"" << it->second << "\"";

+                auto start = cbegin(attr);

+                auto end   = cend(attr);

+                if ( start != end ) {

+                        *pout_ << " " << get<0>(*start) << "=\"" << get<1>(*start) << "\"";

 

-                                ++it;   // skip first Element

-                                for ( ; it != end; ++it )

-                                        *pout_ << ",  " << it->first << "=\"" << it->second << "\"";

+                        ++start; // skip first Element

+                        for ( ; start != end; ++start ) {

+                                *pout_ << ",  " << get<0>(*start) << "=\"" << get<1>(*start) << "\"";

                         }

-

-                        *pout_ << ">" << endl;

                 }

 

-                void handle_end(const string& name)

-                {

-                        *pout_ << string(--depth_ * indent_, ' ')

-                               << "</" << name << ">"

-                               << endl;

+                *pout_ << ">" << '\n';

+        }

+

+        void handle_end(string_view name) override

+        {

+                *pout_ << string(--depth_ * indent_, ' ')

+                       << "</" << name << ">"

+                       << '\n';

+        }

+        void handle_cdata_start() override

+        {

+                *pout_ << string(depth_ * indent_, ' ')

+                       << "<![CDATA[" << '\n';

+        }

+

+        void handle_cdata_end() override

+        {

+                *pout_ << string(depth_ * indent_, ' ')

+                       << "]]>" << '\n';

+        }

+

+        static bool contains_only_whitespace(span<const char> data)

+        {

+                return ranges::all_of(data, [](unsigned char chr) {

+                        return std::isspace(chr);

+                });

+        }

+

+        void handle_character_data(span<const char> data) override

+        {

+                if ( contains_only_whitespace(data) ) {

+                        return;

                 }

 

-        private:

-                ostream* pout_;

-                size_t depth_;

-                size_t indent_;

+                *pout_ << string(depth_ * indent_, ' ') << "Data: ";

+                pout_->write(data.data(), static_cast<streamsize>(data.size()));

+                *pout_ << '\n';

+        }

+

+private:

+        ostream* pout_;

+        size_t   depth_{};

+        size_t   indent_;

 };

 

 int

@@ -53,6 +83,6 @@ main()
                 myxml.parse(cin);

         }

         catch ( exception& e ) {

-                cerr << "Fehler: " << e.what() << endl;

+                cerr << "Fehler: " << e.what() << '\n';

         }

 }