Support a default destructor for PJ objects

1 files changed, 5 insertions, 59 deletions

diff --git a/src/projects.h b/src/projects.h
index 872bf816..ece88cde 100644
--- a/src/projects.h
+++ b/src/projects.h
@@ -253,62 +253,8 @@ struct PJconsts {
 
     void (*spc)(LP, PJ *, struct FACTORS *);
 
-    void (*pfree)(PJ *);
-
-    /*************************************************************************************
-
-                              E R R O R   R E P O R T I N G
-
-    **************************************************************************************
-
-        Currently, we're doing error reporting through the context->last_errno indicator.
-
-        It is, however, not entirely sure this will be the right way to do it in all
-        cases: During allocation/initialization, it is certainly nice to have a higher
-        level error indicator, since we primarily signal "something went wrong", by
-        returning 0 from the pj_init family of functions - and with a null return we
-        cannot pass messages through internal state in the PJ object.
-
-        Historically, the errno variable has been used for that kind of messages, but
-        apparently, thread safety was added to PROJ.4 at a time where it was not clear
-        that errno is actually thread local.
-
-        Additionally, errno semantics has historically been misinterpreted in parts of
-        pj_init.c, a misinterpretation, that was mitigated by a hack in pj_malloc.c
-        some 15 years ago.
-
-        This PJ-local errno is a first step towards a more structured approach to
-        error reporting, being implemented in the OBS_API (cf. pj_obs_api.[ch]), and
-        related plumbing efforts.
-        
-        In due course this will let us get rid of the pj_malloc.c hack, and allow us
-        to introduce a more layered error reporting structure, where errors are
-        reported where they occur, and bubble up to the higher levels (context->errno,
-        then thread local errno), so the highest level indicate "something went wrong
-        somewhere", then the more localized ones can be used for pinpointing: 
-        
-        errno:               "something went wrong somewhere on this thread",
-        context->last_errno: "something went wrong in some PROJ.4 related code",
-        PJ->last_errno:      "It was in THIS PJ something went wrong",
-        pj_strerrno:         "This was what went wrong".
-
-        Which will be quite helpful, once fully implemented, especially for 
-        debugging complex transformation pipelines, while still maintaining backward
-        compatibility in the messaging system.
-
-        Note that there is even a global pj_errno, which is here and there accessed
-        without acquiring lock. This, and the practise of resetting the thread local
-        errno, should be given some consideration during the cleanup of the error
-        reporting system.
-
-        The name "last_errno", rather than "errno" is used partially for alignment
-        with the context->last_errno, partially because in a multithreaded environment,
-        errno is a macro, and spurious spaces turning "errno" into a separate token
-        will expose it to macro expansion, to the tune of much confusion and agony.
-
-    **************************************************************************************/
-    int last_errno;
-
+    void *(*destructor)(PJ *, int);
+    
 
     /*************************************************************************************
 
@@ -616,7 +562,7 @@ C_NAMESPACE PJ *pj_##name (PJ *P) {                          \
     P = (PJ*) pj_calloc (1, sizeof(PJ));                     \
     if (0==P)                                                \
         return 0;                                            \
-    P->pfree = freeup;                                       \
+    P->destructor = pj_default_destructor;                   \
     P->descr = des_##name;                                   \
     return P;                                                \
 }                                                            \
@@ -707,8 +653,6 @@ int pj_datum_set(projCtx,paralist *, PJ *);
 int pj_prime_meridian_set(paralist *, PJ *);
 int pj_angular_units_set(paralist *, PJ *);
 
-void pj_prepare (PJ *P, const char *description, void (*freeup)(struct PJconsts *), size_t sizeof_struct_opaque);
-
 paralist *pj_clone_paralist( const paralist* );
 paralist *pj_search_initcache( const char *filekey );
 void      pj_insert_initcache( const char *filekey, const paralist *list);
@@ -822,6 +766,8 @@ struct PJ_LIST             *pj_get_list_ref( void );
 struct PJ_SELFTEST_LIST    *pj_get_selftest_list_ref ( void );
 struct PJ_PRIME_MERIDIANS  *pj_get_prime_meridians_ref( void );
 
+void *pj_default_destructor (PJ *P, int errlev);
+
 double pj_atof( const char* nptr );
 double pj_strtod( const char *nptr, char **endptr );
 void   pj_freeup_plain (PJ *P);