fix compiler and ci warnings

Clean up the remaining warnings that are under h5pp's control.

- fix discarded exception objects and a size_t-to-int narrowing site
- replace unsafe string copying in vlen/fixed-string helpers and user-type tests
- update Conan metadata to the C++20 baseline and quiet the optional libaec lookup
- reduce workflow noise from apt usage, cache path setup, coverage capture, and MSVC test-only complex warnings

Author: DavidAce

.github/workflows/macos14.yml

@@ -33,6 +33,10 @@ jobs:
         with:
           python-version: '3.x'
 
+      - name: Prepare cache directories
+        run: |
+          mkdir -p ~/.ccache ~/.conan2 install/github-actions-${{ matrix.manager }}
+
       - name: Setup caches
         id: h5pp-cache
         uses: actions/cache@v4.2.0

.github/workflows/macos15.yml

@@ -33,6 +33,10 @@ jobs:
         with:
           python-version: '3.x'
 
+      - name: Prepare cache directories
+        run: |
+          mkdir -p ~/.ccache ~/.conan2 install/github-actions-${{ matrix.manager }}
+
       - name: Setup caches
         id: h5pp-cache
         uses: actions/cache@v4.2.0

.github/workflows/ubuntu22.yml

@@ -36,7 +36,11 @@ jobs:
 
       - name: Update apt
         run: |
-          sudo apt update
+          sudo apt-get update
+
+      - name: Prepare cache directories
+        run: |
+          mkdir -p ~/.ccache ~/.conan2 install/github-actions-${{ matrix.manager }}
 
 
       - name: Setup caches
@@ -52,22 +56,22 @@ jobs:
       - name: Setup gcc
         if: matrix.compiler == 'gcc'
         run: |
-          sudo apt install gcc-12 g++-12 -y
+          sudo apt-get install gcc-12 g++-12 -y
           echo "FC=gfortran-12" >> $GITHUB_ENV
           echo "CC=gcc-12"      >> $GITHUB_ENV
           echo "CXX=g++-12"     >> $GITHUB_ENV
 
       - name: Setup clang
         if: matrix.compiler == 'clang'
         run: |
-          sudo apt install clang-15 libomp-15-dev -y
+          sudo apt-get install clang-15 libomp-15-dev -y
           echo "FC=gfortran-12" >> $GITHUB_ENV
           echo "CC=clang-15"    >> $GITHUB_ENV
           echo "CXX=clang++-15" >> $GITHUB_ENV
 
       - name: Setup build tools
         run: |
-          sudo apt install ccache ninja-build gcovr lcov -y
+          sudo apt-get install ccache ninja-build gcovr lcov -y
           echo "CMAKE_GENERATOR=Ninja" >> $GITHUB_ENV
 
       - name: Setup conan

.github/workflows/ubuntu24.yml

@@ -39,7 +39,11 @@ jobs:
 
       - name: Update apt
         run: |
-          sudo apt update
+          sudo apt-get update
+
+      - name: Prepare cache directories
+        run: |
+          mkdir -p ~/.ccache ~/.conan2 install/github-actions-${{ matrix.manager }}
 
 
       - name: Setup caches
@@ -55,27 +59,27 @@ jobs:
       - name: Setup gcc
         if: matrix.compiler == 'gcc'
         run: |
-          sudo apt install gcc-14 g++-14 -y
+          sudo apt-get install gcc-14 g++-14 -y
           echo "FC=gfortran-14" >> $GITHUB_ENV
           echo "CC=gcc-14"      >> $GITHUB_ENV
           echo "CXX=g++-14"     >> $GITHUB_ENV
 
       - name: Setup clang
         if: matrix.compiler == 'clang'
         run: |
-          sudo apt install clang-18 libomp-18-dev -y
+          sudo apt-get install clang-18 libomp-18-dev -y
           echo "FC=gfortran-14" >> $GITHUB_ENV
           echo "CC=clang-18"    >> $GITHUB_ENV
           echo "CXX=clang++-18" >> $GITHUB_ENV
 
       - name: Setup build tools
         run: |
-          sudo apt install ccache ninja-build gcovr lcov -y
+          sudo apt-get install ccache ninja-build gcovr lcov -y
           echo "CMAKE_GENERATOR=Ninja" >> $GITHUB_ENV
 
       - name: Setup apt packages (dependencies)
         if: matrix.manager == 'find'
-        run: sudo apt install libhdf5-dev libaec-dev libfmt-dev libspdlog-dev libeigen3-dev catch2 -y
+        run: sudo apt-get install libhdf5-dev libaec-dev libfmt-dev libspdlog-dev libeigen3-dev catch2 -y
 
       - name: Setup conan
         if: matrix.manager == 'conan'
@@ -114,8 +118,8 @@ jobs:
       - name: Generate coverage report
         if: matrix.compiler == 'gcc' && matrix.manager == 'find'
         run: |
-          lcov --gcov-tool=gcov-14 --capture --directory build/github-actions-find --output-file coverage.info
-          lcov --gcov-tool=gcov-14 --ignore-errors unused --remove coverage.info '*/test-*' '/usr/*' 'include/c++/*' '*include/fmt/*' '*include/spdlog/*' '*/Eigen/*' '*/hdf5/*' '*catch.hpp' --output-file coverage.info
+          lcov --gcov-tool=gcov-14 --capture --rc geninfo_unexecuted_blocks=1 --no-external --directory build/github-actions-find --output-file coverage.info
+          lcov --gcov-tool=gcov-14 --ignore-errors unused --remove coverage.info '*/test-*' '*catch.hpp' --output-file coverage.info
           lcov --gcov-tool=gcov-14 --list coverage.info
 
       - name: Upload coverage to Codecov

.github/workflows/windows2022.yml

@@ -32,6 +32,12 @@ jobs:
         with:
           python-version: '3.x'
 
+      - name: Prepare cache directories
+        shell: pwsh
+        run: |
+          New-Item -ItemType Directory -Force -Path "$HOME\\.conan2" | Out-Null
+          New-Item -ItemType Directory -Force -Path "install/github-actions-${{ matrix.manager }}" | Out-Null
+
       - name: Setup caches
         id: h5pp-cache
         uses: actions/cache@v4.2.0

cmake/HDF5TargetUtils.cmake

@@ -244,9 +244,9 @@ function(h5pp_get_modern_hdf5_target_name)
     find_package(ZLIB ${HDF5_ZLIB_REQUIRED} QUIET BYPASS_PROVIDER)
     find_package(SZIP ${HDF5_SZIP_REQUIRED} QUIET BYPASS_PROVIDER)
     if(NOT DEFINED libaec_FOUND AND NOT TARGET libaec::sz)
-        find_package(libaec ${HDF5_LIBAEC_REQUIRED} BYPASS_PROVIDER)
+        find_package(libaec ${HDF5_LIBAEC_REQUIRED} QUIET BYPASS_PROVIDER)
     endif()
     find_library(LIBRARY_Z z ${HDF5_z_REQUIRED} QUIET)
     find_library(LIBRARY_SZ sz ${HDF5_sz_REQUIRED} QUIET)
     find_library(LIBRARY_libaec aec ${HDF5_libaec_REQUIRED} QUIET)
-endfunction()
+endfunction()

conanfile.py

@@ -12,10 +12,10 @@
 class H5ppConan(ConanFile):
     name = "h5pp"
     version = "2.0.0"
-    description = "A C++17 wrapper for HDF5 with focus on simplicity"
+    description = "A C++20 wrapper for HDF5 with focus on simplicity"
     homepage = "https://github.com/DavidAce/h5pp"
     author = "DavidAce <aceituno@kth.se>"
-    topics = ("hdf5", "binary", "storage", "header-only", "cpp17")
+    topics = ("hdf5", "binary", "storage", "header-only", "cpp20")
     url = "https://github.com/DavidAce/h5pp"
     license = "MIT"
     settings = "os", "compiler", "build_type", "arch"
@@ -47,6 +47,7 @@ def _compilers_minimum_version(self):
             "Visual Studio": "15.7",
             "clang": "6",
             "apple-clang": "10",
+            "msvc": "193",
         }
 
     def config_options(self):
@@ -78,14 +79,12 @@ def validate(self):
             if self.options.get_safe('with_float128'):
                 check_min_cppstd(self, 23)
             else:
-                check_min_cppstd(self, 17)
+                check_min_cppstd(self, 20)
 
         minimum_version = self._compilers_minimum_version.get(str(self.settings.compiler), False)
         if minimum_version:
             if Version(self.settings.compiler.version) < minimum_version:
-                raise ConanInvalidConfiguration("h5pp requires C++17, which your compiler does not support.")
-        else:
-            self.output.warning("h5pp requires C++17. Your compiler is unknown. Assuming it supports C++17.")
+                raise ConanInvalidConfiguration("h5pp requires C++20, which your compiler does not support.")
 
         if self.options.get_safe('with_float128') and  self.options.get_safe('with_quadmath'):
             raise ConanInvalidConfiguration("These are mutually exclusive options: h5pp:with_float128 and h5pp:with_quadmath")

include/h5pp/details/h5ppFstr.h

@@ -3,6 +3,7 @@
 #include "h5ppHid.h"
 #include "h5ppLogger.h"
 #include "h5ppTypeSfinae.h"
+#include <algorithm>
 #include <charconv>
 #include <cstdlib>
 #include <cstring>
@@ -13,6 +14,11 @@
 namespace h5pp::type::flen {
     namespace internal {
         static constexpr bool debug_fstr_t = false;
+
+        inline void copy_bytes(char *dst, const char *src, size_t len) {
+            if(len == 0) return;
+            std::memcpy(dst, src, len);
+        }
     }
 
     template<size_t N>
@@ -130,7 +136,7 @@ namespace h5pp::type::flen {
     template<size_t N>
     inline fstr_t<N>::fstr_t(const fstr_t &v) {
         if(v.ptr == nullptr) return;
-        strncpy(ptr, v.ptr, N);
+        internal::copy_bytes(ptr, v.ptr, N - 1);
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t copied into {}: {}", fmt::ptr(ptr), ptr);
@@ -139,7 +145,7 @@ namespace h5pp::type::flen {
     template<size_t N>
     inline fstr_t<N>::fstr_t(const char *v) {
         if(v == nullptr) return;
-        strncpy(ptr, v, N);
+        internal::copy_bytes(ptr, v, std::min(strlen(v), N - 1));
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t copied into {}: {}", fmt::ptr(ptr), ptr);
@@ -148,7 +154,7 @@ namespace h5pp::type::flen {
     template<size_t N>
     inline fstr_t<N>::fstr_t(std::string_view v) {
         if(v.empty()) return;
-        strncpy(ptr, v.data(), N);
+        internal::copy_bytes(ptr, v.data(), std::min(v.size(), N - 1));
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t copied into {}: {}", fmt::ptr(ptr), ptr);
@@ -158,7 +164,7 @@ namespace h5pp::type::flen {
     template<size_t N>
     inline fstr_t<N>::fstr_t(fstr_t &&v) noexcept {
         if(v.ptr == nullptr) return;
-        strncpy(ptr, v.ptr, N);
+        internal::copy_bytes(ptr, v.ptr, N - 1);
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t copied into {}: {}", fmt::ptr(ptr), ptr);
@@ -173,7 +179,7 @@ namespace h5pp::type::flen {
     inline fstr_t<N> &fstr_t<N>::operator=(const fstr_t &v) noexcept {
         if(this != &v and ptr != v.ptr) {
             clear();
-            strncpy(ptr, v.ptr, N);
+            internal::copy_bytes(ptr, v.ptr, N - 1);
             ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
             if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t assigned into {}: {}", fmt::ptr(ptr), ptr);
@@ -184,7 +190,7 @@ namespace h5pp::type::flen {
     template<size_t N>
     inline fstr_t<N> &fstr_t<N>::operator=(std::string_view v) {
         clear();
-        strncpy(ptr, v.data(), N);
+        internal::copy_bytes(ptr, v.data(), std::min(v.size(), N - 1));
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t assigned into {}: {}", fmt::ptr(ptr), ptr);
@@ -285,7 +291,7 @@ namespace h5pp::type::flen {
     inline void fstr_t<N>::append(const char *v) {
         if(v == nullptr) return;
         size_t oldlen = size();
-        strncpy(ptr + oldlen, v, N - oldlen);
+        internal::copy_bytes(ptr + oldlen, v, std::min(strlen(v), N - oldlen - 1));
         ptr[N - 1] = '\0';
 #if defined(H5PP_USE_FMT)
         if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t appended to {} | {} -> {}", fmt::ptr(ptr), v, ptr);
@@ -299,7 +305,13 @@ namespace h5pp::type::flen {
 
     template<size_t N>
     inline void fstr_t<N>::append(std::string_view v) {
-        append(v.data());
+        if(v.empty()) return;
+        size_t oldlen = size();
+        internal::copy_bytes(ptr + oldlen, v.data(), std::min(v.size(), N - oldlen - 1));
+        ptr[N - 1] = '\0';
+#if defined(H5PP_USE_FMT)
+        if constexpr(internal::debug_fstr_t) h5pp::logger::log->info("fstr_t appended to {} | {} -> {}", fmt::ptr(ptr), v, ptr);
+#endif
     }
 
     template<size_t N>
@@ -448,4 +460,4 @@ struct fmt::formatter<h5pp::fstr_t<N>> : formatter<std::string_view> {
     auto format(const h5pp::fstr_t<N> &f, format_context &ctx) { return fmt::formatter<string_view>::format(f.c_str(), ctx); }
 };
     #endif
-#endif
+#endif

include/h5pp/details/h5ppHdf5.h

@@ -149,7 +149,7 @@ namespace h5pp::hdf5 {
 
     [[nodiscard]] inline hsize_t getSizeSelected(const hid::h5s &space) {
         hssize_t size = H5Sget_select_npoints(space);
-        if(size < 0) h5pp::runtime_error("getSizeSelected: H5Sget_select_npoints failed");
+        if(size < 0) throw h5pp::runtime_error("getSizeSelected: H5Sget_select_npoints failed");
         return type::safe_cast<hsize_t>(size);
     }
 
@@ -1502,17 +1502,17 @@ namespace h5pp::hdf5 {
             auto newDimensions = dataInfo.dataDims.value();
             if(dataInfo.dataSlab and dataInfo.dataSlab->extent) {
                 if(dataInfo.dataDims->size() != dataInfo.dataSlab->extent->size()) {
-                    h5pp::runtime_error("rank mismatch: \n data dims {}\n data slab {}",
-                                        dataInfo.dataDims.value(),
-                                        dataInfo.dataSlab->string());
+                    throw h5pp::runtime_error("rank mismatch: \n data dims {}\n data slab {}",
+                                              dataInfo.dataDims.value(),
+                                              dataInfo.dataSlab->string());
                 }
                 newDimensions = dataInfo.dataSlab->extent.value();
             }
             if(dsetInfo.dsetSlab and dsetInfo.dsetSlab->offset and dsetInfo.dsetSlab->extent) {
                 const auto &offset = dsetInfo.dsetSlab->offset.value();
                 const auto &extent = dsetInfo.dsetSlab->extent.value();
                 if(newDimensions.size() != offset.size() or newDimensions.size() != extent.size())
-                    h5pp::runtime_error("rank mismatch: \n data dims {}\n dset slab {}", newDimensions, dsetInfo.dsetSlab->string());
+                    throw h5pp::runtime_error("rank mismatch: \n data dims {}\n dset slab {}", newDimensions, dsetInfo.dsetSlab->string());
                 for(size_t idx = 0; idx < newDimensions.size(); idx++)
                     newDimensions[idx] = std::max(newDimensions[idx], offset[idx] + extent[idx]);
             }
@@ -2017,7 +2017,7 @@ namespace h5pp::hdf5 {
             haddr_t chaddr = 0;
             hsize_t chsize = 0;
             herr_t  eci    = H5Dget_chunk_info_by_coord(h5dset, chunkOffset.data(), &mask, &chaddr, &chsize);
-            if(eci < 0) h5pp::runtime_error("Failed to get chunk info for offset {}", chunkOffset);
+            if(eci < 0) throw h5pp::runtime_error("Failed to get chunk info for offset {}", chunkOffset);
 
             if(chsize == 0 or chaddr == HADDR_UNDEF) {
                 h5pp::logger::log->trace("Reading chunk at offset {}: chunk is not allocated yet, clearing output buffer", chunkOffset);
@@ -2664,7 +2664,7 @@ namespace h5pp::hdf5 {
 #else
                 herr_t reclaim_err = H5Dvlen_reclaim(attrInfo.h5Type.value(), attrInfo.h5Space.value(), H5P_DEFAULT, vdata.data());
 #endif
-                if(reclaim_err < 0) h5pp::runtime_error("readAttribute: failed to reclaim variable-length array buffer");
+                if(reclaim_err < 0) throw h5pp::runtime_error("readAttribute: failed to reclaim variable-length array buffer");
             } else {
                 // All the elements in the dataset have the same string size
                 // The whole dataset is read into a contiguous block of memory.
@@ -2944,7 +2944,7 @@ namespace h5pp::hdf5 {
         /* Step 1: Get the dataset and memory spaces */
         std::array<hsize_t, 1> dataDims  = {extent.value()};                  /* create a simple memory data space */
         hid::h5s               dsetSpace = H5Dget_space(info.h5Dset.value()); /* get a copy of the new file data space for writing */
-        hid::h5s               dataSpace = H5Screate_simple(dataDims.size(), dataDims.data(), nullptr);
+        hid::h5s               dataSpace = H5Screate_simple(type::safe_cast<int>(dataDims.size()), dataDims.data(), nullptr);
 
         /* Step 2: draw a region in the dataset */
         std::array<hsize_t, 1> dsetOffset = {offset.value()};
@@ -3325,12 +3325,12 @@ namespace h5pp::hdf5 {
             herr_t             retval = H5Dread(info.h5Dset.value(), h5t_fields, dataSpace, dsetSpace, plists.dsetXfer, vdata.data());
             if(retval < 0) {
                 auto h5t_info = getH5TInfo(h5t_fields);
-                h5pp::runtime_error("readTableField: H5Dread failed for variable-length field data\n"
-                                    "table [{}] | {}{}{}",
-                                    info.tablePath.value(),
-                                    h5t_info.string(),
-                                    h5t_info.numMembers ? "\n" : "",
-                                    h5t_info.string_members());
+                throw h5pp::runtime_error("readTableField: H5Dread failed for variable-length field data\n"
+                                          "table [{}] | {}{}{}",
+                                          info.tablePath.value(),
+                                          h5t_info.string(),
+                                          h5t_info.numMembers ? "\n" : "",
+                                          h5t_info.string_members());
             }
 
             // Now vdata contains the dataset selection, and we need to put the data into the user-given container.
@@ -3386,12 +3386,12 @@ namespace h5pp::hdf5 {
 
             if(reclaim_err) {
                 auto h5t_info = getH5TInfo(h5t_fields);
-                h5pp::runtime_error("readTableField: H5Dvlen_reclaim failed when reading variable-length field data\n"
-                                    "table [{}] | {}{}{}",
-                                    info.tablePath.value(),
-                                    h5t_info.string(),
-                                    h5t_info.numMembers ? "\n" : "",
-                                    h5t_info.string_members());
+                throw h5pp::runtime_error("readTableField: H5Dvlen_reclaim failed when reading variable-length field data\n"
+                                          "table [{}] | {}{}{}",
+                                          info.tablePath.value(),
+                                          h5t_info.string(),
+                                          h5t_info.numMembers ? "\n" : "",
+                                          h5t_info.string_members());
             }
             return;
         } else if constexpr(std::is_same_v<DataType, std::vector<std::byte>>) {