fix remaning std::fread usage - check return value

plugins/input/csv/csv_featureset.cpp

@@ -97,7 +97,10 @@ mapnik::feature_ptr csv_featureset::next()
         std::fseek(file_.get(), file_offset, SEEK_SET);
         std::vector<char> record;
         record.resize(size);
-        std::fread(record.data(), size, 1, file_.get());
+        if (std::fread(record.data(), size, 1, file_.get()) != 1)
+        {
+            return mapnik::feature_ptr();
+        }
         auto const* start = record.data();
         auto const*  end = start + record.size();
 #endif

plugins/input/csv/csv_index_featureset.cpp

@@ -119,7 +119,10 @@ mapnik::feature_ptr csv_index_featureset::next()
         std::fseek(file_.get(), pos.first, SEEK_SET);
         std::vector<char> record;
         record.resize(pos.second);
-        std::fread(record.data(), pos.second, 1, file_.get());
+        if (std::fread(record.data(), pos.second, 1, file_.get()) != 1)
+        {
+            return mapnik::feature_ptr();
+        }
         auto const* start = record.data();
         auto const*  end = start + record.size();
 #endif

plugins/input/geojson/geojson_datasource.cpp

@@ -155,9 +155,9 @@ geojson_datasource::geojson_datasource(parameters const& params)
 
         std::string file_buffer;
         file_buffer.resize(file.size());
-        std::fread(&file_buffer[0], file.size(), 1, file.get());
+        auto count = std::fread(&file_buffer[0], file.size(), 1, file.get());
         char const* start = file_buffer.c_str();
-        char const* end = start + file_buffer.length();
+        char const* end = (count == 1) ? start + file_buffer.length() : start;
 #else
         boost::optional<mapnik::mapped_region_ptr> mapped_region =
             mapnik::mapped_memory_cache::instance().find(filename_, false);
@@ -226,9 +226,9 @@ void geojson_datasource::initialise_disk_index(std::string const& filename)
         std::fseek(file.get(), pos.first, SEEK_SET);
         std::vector<char> record;
         record.resize(pos.second);
-        std::fread(record.data(), pos.second, 1, file.get());
+        auto count = std::fread(record.data(), pos.second, 1, file.get());
         auto const* start = record.data();
-        auto const*  end = start + record.size();
+        auto const*  end = (count == 1) ? start + record.size() : start;
         mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx, -1));
         try
         {
@@ -471,9 +471,9 @@ boost::optional<mapnik::datasource_geometry_t> geojson_datasource::get_geometry_
             std::fseek(file.get(), pos.first, SEEK_SET);
             std::vector<char> record;
             record.resize(pos.second);
-            std::fread(record.data(), pos.second, 1, file.get());
+            auto count = std::fread(record.data(), pos.second, 1, file.get());
             auto const* start = record.data();
-            auto const*  end = start + record.size();
+            auto const*  end = (count == 1) ? start + record.size() : start;
             mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx, -1)); // temp feature
             try
             {
@@ -533,11 +533,10 @@ boost::optional<mapnik::datasource_geometry_t> geojson_datasource::get_geometry_
             std::fseek(file.get(), file_offset, SEEK_SET);
             std::vector<char> json;
             json.resize(size);
-            std::fread(json.data(), size, 1, file.get());
+            auto count_objects = std::fread(json.data(), size, 1, file.get());
-
             using chr_iterator_type = char const*;
             chr_iterator_type start2 = json.data();
-            chr_iterator_type end2 = start2 + json.size();
+            chr_iterator_type end2 = (count_objects == 1) ? start2 + json.size() : start2;
 
             mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx, -1)); // temp feature
             try

plugins/input/geojson/geojson_index_featureset.cpp

@@ -87,9 +87,9 @@ mapnik::feature_ptr geojson_index_featureset::next()
         std::fseek(file_.get(), pos.first, SEEK_SET);
         std::vector<char> record;
         record.resize(pos.second);
-        std::fread(record.data(), pos.second, 1, file_.get());
+        auto count = std::fread(record.data(), pos.second, 1, file_.get());
         auto const* start = record.data();
-        auto const*  end = start + record.size();
+        auto const*  end = (count == 1) ? start + record.size() : start;
 #endif
         static const mapnik::transcoder tr("utf8");
         mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_, feature_id_++));

plugins/input/geojson/geojson_memory_index_featureset.cpp

@@ -61,10 +61,10 @@ mapnik::feature_ptr geojson_memory_index_featureset::next()
         std::fseek(file_.get(), file_offset, SEEK_SET);
         std::vector<char> json;
         json.resize(size);
-        std::fread(json.data(), size, 1, file_.get());
+        auto count = std::fread(json.data(), size, 1, file_.get());
         using chr_iterator_type = char const*;
         chr_iterator_type start = json.data();
-        chr_iterator_type end = start + json.size();
+        chr_iterator_type end = (count == 1) ? start + json.size() : start;
         static const mapnik::transcoder tr("utf8");
         mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_, feature_id_++));
         mapnik::json::parse_feature(start, end, *feature, tr); // throw on failure

plugins/input/topojson/topojson_datasource.cpp

@@ -171,8 +171,8 @@ topojson_datasource::topojson_datasource(parameters const& params)
         }
         std::string file_buffer;
         file_buffer.resize(file.size());
-        std::fread(&file_buffer[0], file.size(), 1, file.get());
+        auto count = std::fread(&file_buffer[0], file.size(), 1, file.get());
-        parse_topojson(file_buffer.c_str());
+        if (count == 1) parse_topojson(file_buffer.c_str());
     }
 }
 

utils/mapnik-index/process_geojson_file_x3.cpp

@@ -252,9 +252,9 @@ std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & b
     }
     std::string file_buffer;
     file_buffer.resize(file.size());
-    std::fread(&file_buffer[0], file.size(), 1, file.get());
+    auto count = std::fread(&file_buffer[0], file.size(), 1, file.get());
     base_iterator_type start = file_buffer.c_str();
-    base_iterator_type end = start + file_buffer.length();
+    base_iterator_type end = (count == 1) ? start + file_buffer.length() : start;
 #endif
     base_iterator_type itr = start; // make a copy to preserve `start` iterator state
     try