Allow no null byte on WKT

.github/workflows/codecov.yml

@@ -41,7 +41,7 @@ jobs:
           lcov --remove coverage.info '/usr/*' --output-file coverage.info
           lcov --list coverage.info
       - name: Upload coverage to codecov
-        uses: codecov/codecov-action@5c93f7ab87f1aa9b956609bbc4b50a6e747fe2fb
+        uses: codecov/codecov-action@fb8b3582c8e4def4969c97caa2f19720cb33a72f # v7.0.0
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           files: coverage.info

src/las_reader.hpp

@@ -116,14 +116,14 @@ class LASReader {
           if (record.is_ogc_math_transform_wkt()) {
             std::vector<char> wkt(record.record_length_after_header);
             LASPP_CHECK_READ(*m_input_stream, wkt.data(), record.record_length_after_header);
-            std::string wkt_string(wkt.begin(), wkt.end());
+            std::string wkt_string(las_packed_string(std::string_view(wkt.data(), wkt.size())));
             LASPP_ASSERT(!m_math_wkt.has_value(), "Multiple math WKTs found in header");
             m_math_wkt.emplace(wkt_string);
           }
           if (record.is_ogc_coordinate_system_wkt()) {
             std::vector<char> wkt(record.record_length_after_header);
             LASPP_CHECK_READ(*m_input_stream, wkt.data(), record.record_length_after_header);
-            std::string wkt_string(wkt.data(), wkt.size() - 1);
+            std::string wkt_string(las_packed_string(std::string_view(wkt.data(), wkt.size())));
             LASPP_ASSERT(!m_coordinate_wkt.has_value(), "Multiple coordinate WKTs found in header");
             m_coordinate_wkt.emplace(wkt_string);
           }

src/tests/test_reader.cpp

@@ -100,6 +100,83 @@ int main([[maybe_unused]] int argc, [[maybe_unused]] char* argv[]) {
     }
   }
 
+  {
+    // Some LAS writers store WKT without a trailing null byte, using the full
+    // VLR record length for the WKT text (record_id 2112).
+    const std::string wkt = "WKT_WITHOUT_NULL_BYTE";
+    std::stringstream stream;
+    {
+      LASWriter writer(stream, 0, 0);
+
+      LASVLR wkt_vlr;
+      wkt_vlr.reserved = 0;
+      string_to_arr("LASF_Projection", wkt_vlr.user_id);
+      wkt_vlr.record_id = 2112;
+      wkt_vlr.record_length_after_header = static_cast<uint16_t>(wkt.size());
+      string_to_arr("OGC WKT", wkt_vlr.description);
+      writer.write_vlr(wkt_vlr,
+                       std::span(reinterpret_cast<const std::byte*>(wkt.data()), wkt.size()));
+
+      std::vector<LASPointFormat0> points(1);
+      writer.write_points(std::span<const LASPointFormat0>(points));
+    }
+
+    LASReader reader(stream);
+    LASPP_ASSERT_EQ(reader.coordinate_wkt().value(), wkt);
+    LASPP_ASSERT(!reader.math_wkt().has_value());
+  }
+
+  {
+    // Test math transform WKT (record_id 2111) written via write_wkt with the
+    // math_transform_wkt flag. The writer includes a trailing null byte.
+    const std::string math_wkt = "MATH_TRANSFORM_WKT";
+    std::stringstream stream;
+    {
+      LASWriter writer(stream, 0, 0);
+
+      // Write coordinate WKT first so we can verify wkt() returns it preferentially
+      writer.write_wkt("COORDINATE_WKT");
+      writer.write_wkt(math_wkt, true);
+
+      std::vector<LASPointFormat0> points(1);
+      writer.write_points(std::span<const LASPointFormat0>(points));
+    }
+
+    LASReader reader(stream);
+    LASPP_ASSERT_EQ(reader.coordinate_wkt().value(), "COORDINATE_WKT");
+    LASPP_ASSERT_EQ(reader.math_wkt().value(), math_wkt);
+    // wkt() should return coordinate_wkt when both are present
+    LASPP_ASSERT_EQ(reader.wkt().value(), "COORDINATE_WKT");
+  }
+
+  {
+    // Math transform WKT without a trailing null byte (record_id 2111), matching
+    // the no-null-byte pattern tested for record_id 2112 above.
+    const std::string math_wkt = "MATH_WKT_NO_NULL";
+    std::stringstream stream;
+    {
+      LASWriter writer(stream, 0, 0);
+
+      LASVLR wkt_vlr;
+      wkt_vlr.reserved = 0;
+      string_to_arr("LASF_Projection", wkt_vlr.user_id);
+      wkt_vlr.record_id = 2111;
+      wkt_vlr.record_length_after_header = static_cast<uint16_t>(math_wkt.size());
+      string_to_arr("OGC WKT", wkt_vlr.description);
+      writer.write_vlr(
+          wkt_vlr, std::span(reinterpret_cast<const std::byte*>(math_wkt.data()), math_wkt.size()));
+
+      std::vector<LASPointFormat0> points(1);
+      writer.write_points(std::span<const LASPointFormat0>(points));
+    }
+
+    LASReader reader(stream);
+    LASPP_ASSERT_EQ(reader.math_wkt().value(), math_wkt);
+    LASPP_ASSERT(!reader.coordinate_wkt().has_value());
+    // wkt() falls back to math_wkt when coordinate_wkt is absent
+    LASPP_ASSERT_EQ(reader.wkt().value(), math_wkt);
+  }
+
   {
     // Format 5 includes WavePacketData which is not supported in compressed mode
     // So we only test uncompressed format 5

src/vlr.hpp

@@ -147,6 +147,8 @@ class LASGeoKeys {
 };
 
 // Fixed-width LAS string (user_id, description, ...): may omit a trailing NUL.
+// Also used for WKT VLR payloads where some writers omit the trailing null and
+// store the WKT in the full record_length_after_header bytes.
 inline std::string_view las_packed_string(std::string_view raw) {
   const auto z = raw.find('\0');
   return z == std::string_view::npos ? raw : raw.substr(0, z);