Clone projCppContext context when copying projCtx_t (#2324)

4 files changed, 85 insertions, 0 deletions

diff --git a/include/proj/internal/io_internal.hpp b/include/proj/internal/io_internal.hpp
index 617dffab..31dd70df 100644
--- a/include/proj/internal/io_internal.hpp
+++ b/include/proj/internal/io_internal.hpp
@@ -191,6 +191,8 @@ struct projCppContext {
     explicit projCppContext(PJ_CONTEXT *ctx, const char *dbPath = nullptr,
                             const std::vector<std::string> &auxDbPaths = {});
 
+    projCppContext* clone(PJ_CONTEXT *ctx) const;
+
     // cppcheck-suppress functionStatic
     inline const std::string &getDbPath() const { return dbPath_; }
 
diff --git a/src/ctx.cpp b/src/ctx.cpp
index 1e97e58a..930ae9ea 100644
--- a/src/ctx.cpp
+++ b/src/ctx.cpp
@@ -24,6 +24,9 @@
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  *****************************************************************************/
+#ifndef FROM_PROJ_CPP
+#define FROM_PROJ_CPP
+#endif
 
 #include <errno.h>
 #include <stdlib.h>
@@ -34,6 +37,7 @@
 #include "proj_experimental.h"
 #include "proj_internal.h"
 #include "filemanager.hpp"
+#include "proj/internal/io_internal.hpp"
 
 /************************************************************************/
 /*                             pj_get_ctx()                             */
@@ -152,6 +156,9 @@ projCtx_t::projCtx_t(const projCtx_t& other)
     file_finder_user_data = other.file_finder_user_data;
     networking = other.networking;
     ca_bundle_path = other.ca_bundle_path;
+    if (other.cpp_context != nullptr) {
+        cpp_context = other.cpp_context->clone(this);
+    }
 }
 
 /************************************************************************/
diff --git a/src/iso19111/c_api.cpp b/src/iso19111/c_api.cpp
index 9219f767..947be058 100644
--- a/src/iso19111/c_api.cpp
+++ b/src/iso19111/c_api.cpp
@@ -125,6 +125,18 @@ projCppContext::toVector(const char *const *auxDbPaths) {
 
 // ---------------------------------------------------------------------------
 
+projCppContext* projCppContext::clone(PJ_CONTEXT *ctx) const {
+    projCppContext* newContext = new projCppContext(
+        ctx,
+        getDbPath().c_str(),
+        getAuxDbPaths()
+    );
+    newContext->setAutoCloseDb(getAutoCloseDb());
+    return newContext;
+}
+
+// ---------------------------------------------------------------------------
+
 void projCppContext::closeDb() { databaseContext_ = nullptr; }
 
 // ---------------------------------------------------------------------------
diff --git a/test/unit/test_c_api.cpp b/test/unit/test_c_api.cpp
index 4dd2c326..8c9c3dd1 100644
--- a/test/unit/test_c_api.cpp
+++ b/test/unit/test_c_api.cpp
@@ -132,6 +132,17 @@ class CApi : public ::testing::Test {
         ObjectKeeper &operator=(const ObjectKeeper &) = delete;
     };
 
+    struct PjContextKeeper {
+        PJ_CONTEXT *m_ctxt = nullptr;
+        explicit PjContextKeeper(PJ_CONTEXT *ctxt)
+            : m_ctxt(ctxt) {}
+        ~PjContextKeeper() { proj_context_destroy(m_ctxt); }
+
+        PjContextKeeper(const PjContextKeeper &) = delete;
+        PjContextKeeper &operator=(const PjContextKeeper &) = delete;
+    };
+
+
     struct ContextKeeper {
         PJ_OPERATION_FACTORY_CONTEXT *m_op_ctxt = nullptr;
         explicit ContextKeeper(PJ_OPERATION_FACTORY_CONTEXT *op_ctxt)
@@ -4038,6 +4049,59 @@ TEST_F(Fixture_proj_context_set_autoclose_database,
 
 // ---------------------------------------------------------------------------
 
+TEST_F(CApi, proj_context_clone) {
+    auto c_path = proj_context_get_database_path(m_ctxt);
+    ASSERT_TRUE(c_path != nullptr);
+    std::string path(c_path);
+
+    FILE *f = fopen(path.c_str(), "rb");
+    ASSERT_NE(f, nullptr);
+    fseek(f, 0, SEEK_END);
+    auto length = ftell(f);
+    std::string content;
+    content.resize(static_cast<size_t>(length));
+    fseek(f, 0, SEEK_SET);
+    auto read_bytes = fread(&content[0], 1, content.size(), f);
+    ASSERT_EQ(read_bytes, content.size());
+    fclose(f);
+    const char *tempdir = getenv("TEMP");
+    if (!tempdir) {
+        tempdir = getenv("TMP");
+    }
+    if (!tempdir) {
+        tempdir = "/tmp";
+    }
+    std::string tmp_filename(
+        std::string(tempdir) +
+        "/test_proj_context_set_autoclose_database.db");
+    f = fopen(tmp_filename.c_str(), "wb");
+    if (!f) {
+        std::cerr << "Cannot create " << tmp_filename << std::endl;
+        return;
+    }
+    fwrite(content.data(), 1, content.size(), f);
+    fclose(f);
+
+    auto c_default_path = proj_context_get_database_path(nullptr);
+    std::string default_path(c_default_path ? c_default_path: "");
+    EXPECT_TRUE(proj_context_set_database_path(nullptr, tmp_filename.c_str(),
+                                               nullptr, nullptr));
+
+    PJ_CONTEXT *new_ctx = proj_context_create();
+    EXPECT_TRUE(proj_context_set_database_path(
+        nullptr, default_path.empty() ? nullptr : default_path.c_str(),
+        nullptr, nullptr));
+
+    EXPECT_NE(new_ctx, nullptr);
+    PjContextKeeper keeper_ctxt(new_ctx);
+    auto c_new_path = proj_context_get_database_path(new_ctx);
+    ASSERT_TRUE(c_new_path != nullptr);
+    std::string new_db_path(c_new_path);
+    ASSERT_EQ(new_db_path, tmp_filename);
+}
+
+// ---------------------------------------------------------------------------
+
 TEST_F(CApi, proj_create_crs_to_crs_from_pj) {
 
     auto src = proj_create(m_ctxt, "EPSG:4326");