Function checkProjMajorVersion

src/proj_loader.cpp:321–342

Checks the major PROJ version based on the loaded library filename >= 9. The version is extracted from the library name as a fallback, since the PROJ C-API version query cannot be used safely without ABI guarantees.

/// The version is extracted from the library name as a fallback, since the PROJ C-API version query 
/// cannot be used safely without ABI guarantees.
static void checkProjMajorVersion(const std::string& loadedProjLibPath) {
  std::filesystem::path proj(loadedProjLibPath);
  std::string name = proj.filename().string();

  std::vector<int> versions = parseVersion(name);
  int major = -1;

  if (!versions.empty()) {
    // In libproj.so filenames, the PROJ major version is usually in the second position.
    if (name.rfind("libproj.so.", 0) == 0 && versions.size() > 1) {
      major = versions[1];
    } else {
      major = versions[0];
    }
  }

  if (major < 0) {
    LASMessage(LAS_WARNING, "The loaded PROJ version could not be determined from library name '%s'", name.c_str());
  } else if (major < 9) {
    LASMessage(LAS_WARNING, "The loaded PROJ version (major %d) is older than version 9.0.0. Full functionality cannot be guaranteed with this version.", major);
  }
}

/// Finds the latest QGIS installation path by first checking the `QGIS_PREFIX_PATH` environment variable.
/// If the environment variable is not set, it searches through default installation directories and selects the latest version based on directory names.