Add a proj_cleanup() function to free global resources, typically at process termination

5 files changed, 24 insertions, 1 deletions

diff --git a/docs/source/development/reference/functions.rst b/docs/source/development/reference/functions.rst
index e5f48439..c010fd13 100644
--- a/docs/source/development/reference/functions.rst
+++ b/docs/source/development/reference/functions.rst
@@ -696,6 +696,19 @@ Various
     :type `direction`: PJ_DIRECTION
     :returns: :c:type:`int` 1 if output units is expected in radians, otherwise 0
 
+
+Cleanup
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+.. c:function:: void proj_cleanup()
+
+    .. versionadded:: 6.2.0
+
+    This function frees global resources (grids, cache of +init files). It
+    should be called typically before process termination, and *after* having
+    freed PJ and PJ_CONTEXT objects.
+
+
 C API for ISO-19111 functionality
 +++++++++++++++++++++++++++++++++
 
diff --git a/scripts/reference_exported_symbols.txt b/scripts/reference_exported_symbols.txt
index 6df84099..71de2d0e 100644
--- a/scripts/reference_exported_symbols.txt
+++ b/scripts/reference_exported_symbols.txt
@@ -773,6 +773,7 @@ proj_as_projjson
 proj_as_proj_string
 proj_assign_context
 proj_as_wkt
+proj_cleanup
 proj_clone
 proj_concatoperation_get_step
 proj_concatoperation_get_step_count
diff --git a/src/apps/cs2cs.cpp b/src/apps/cs2cs.cpp
index 20e5e73c..3099c3e8 100644
--- a/src/apps/cs2cs.cpp
+++ b/src/apps/cs2cs.cpp
@@ -645,7 +645,7 @@ int main(int argc, char **argv) {
 
     proj_destroy(transformation);
 
-    pj_deallocate_grids();
+    proj_cleanup();
 
     exit(0); /* normal completion */
 }
diff --git a/src/malloc.cpp b/src/malloc.cpp
index 817f8f20..393437e3 100644
--- a/src/malloc.cpp
+++ b/src/malloc.cpp
@@ -255,3 +255,10 @@ PJ *pj_default_destructor (PJ *P, int errlev) {   /* Destructor */
     delete P;
     return nullptr;
 }
+
+/*****************************************************************************/
+void proj_cleanup() {
+/*****************************************************************************/
+  pj_clear_initcache();
+  pj_deallocate_grids();
+}
diff --git a/src/proj.h b/src/proj.h
index 9cf83df7..e5e9df4c 100644
--- a/src/proj.h
+++ b/src/proj.h
@@ -458,6 +458,8 @@ double PROJ_DLL proj_todeg (double angle_in_radians);
 double PROJ_DLL proj_dmstor(const char *is, char **rs);
 char PROJ_DLL * proj_rtodms(char *s, double r, int pos, int neg);
 
+void PROJ_DLL proj_cleanup(void);
+
 /*! @endcond */
 
 /* ------------------------------------------------------------------------- */