First steps toward simplified macros/internals

The brief version::

In an attempt to make proj.4 code slightly more secure and much easier
to read and maintain, I'm trying to eliminate a few unfortunate design
decisions from the early days of proj.4

The work will be *very* intrusive, especially in the PJ_xxx segment of
the code tree, but great care has been taken to design a process that
can be implemented stepwise and localized, one projection at a time,
then finalized with a relatively small and concentrated work package.

The (very) long version: See the comments in PJ_minimal.c

1 files changed, 55 insertions, 23 deletions

diff --git a/src/projects.h b/src/projects.h
index 411a3403..3106eb76 100644
--- a/src/projects.h
+++ b/src/projects.h
@@ -48,7 +48,7 @@
 #define C_NAMESPACE extern "C"
 #define C_NAMESPACE_VAR extern "C"
 extern "C" {
-#else    
+#else
 #define C_NAMESPACE extern
 #define C_NAMESPACE_VAR
 #endif
@@ -132,8 +132,8 @@ typedef struct {
 
 /* datum_type values */
 #define PJD_UNKNOWN   0
-#define PJD_3PARAM    1   
-#define PJD_7PARAM    2   
+#define PJD_3PARAM    1
+#define PJD_7PARAM    2
 #define PJD_GRIDSHIFT 3
 #define PJD_WGS84     4   /* WGS84 (or anything considered equivelent) */
 
@@ -143,7 +143,7 @@ typedef struct {
 #define PJD_ERR_GRID_AREA           -48
 #define PJD_ERR_CATALOG             -49
 
-#define USE_PROJUV 
+#define USE_PROJUV
 
 typedef struct { double u, v; } projUV;
 typedef struct { double r, i; }	COMPLEX;
@@ -163,7 +163,7 @@ typedef struct { double lam, phi, z; } LPZ;
 
 typedef union { double  f; int  i; char *s; } PROJVALUE;
 struct PJconsts;
-    
+
 struct PJ_LIST {
 	char	*id;		/* projection keyword */
 	struct PJconsts	*(*proj)(struct PJconsts*);/* projection entry point */
@@ -197,14 +197,14 @@ typedef struct {
     double ll_long;      /* lower left corner coordinates (radians) */
     double ll_lat;
     double ur_long;      /* upper right corner coordinates (radians) */
-    double ur_lat; 
+    double ur_lat;
 } PJ_Region;
 
 struct DERIVS {
     double x_l, x_p; /* derivatives of x for lambda-phi */
     double y_l, y_p; /* derivatives of y for lambda-phi */
 };
-    
+
 struct FACTORS {
 	struct DERIVS der;
 	double h, k;	/* meridinal, parallel scales */
@@ -226,12 +226,18 @@ typedef struct ARG_list {
 	/* base projection data structure */
 
 
+#ifdef PJ_LIB__
+    /* we need this forward declaration in order to be able to add a
+       pointer to struct opaque to the typedef struct PJconsts below */
+    struct opaque;
+#endif
+
 typedef struct PJconsts {
     projCtx_t *ctx;
 	XY  (*fwd)(LP, struct PJconsts *);
 	LP  (*inv)(XY, struct PJconsts *);
         XYZ (*fwd3d)(LPZ, struct PJconsts *);
-        LPZ (*inv3d)(XYZ, struct PJconsts *); 
+        LPZ (*inv3d)(XYZ, struct PJconsts *);
 	void (*spc)(LP, struct PJconsts *, struct FACTORS *);
 	void (*pfree)(struct PJconsts *);
 	const char *descr;
@@ -253,7 +259,7 @@ typedef struct PJconsts {
 		x0, y0, /* easting and northing */
 		k0,	/* general scaling factor */
 		to_meter, fr_meter; /* cartesian scaling */
-    
+
         int     datum_type; /* PJD_UNKNOWN/3PARAM/7PARAM/GRIDSHIFT/WGS84 */
         double  datum_params[7];
         struct _pj_gi **gridlist;
@@ -272,9 +278,9 @@ typedef struct PJconsts {
         /* New Datum Shift Grid Catalogs */
         char   *catalog_name;
         struct _PJ_GridCatalog *catalog;
-    
+
         double   datum_date;
-    
+
         struct _pj_gi *last_before_grid;
         PJ_Region     last_before_region;
         double        last_before_date;
@@ -283,6 +289,10 @@ typedef struct PJconsts {
         PJ_Region     last_after_region;
         double        last_after_date;
 
+#ifdef PJ_LIB__
+        struct opaque *opaq;
+#endif
+
 #ifdef PROJ_PARMS__
 PROJ_PARMS__
 #endif /* end of optional extensions */
@@ -297,7 +307,7 @@ extern struct PJ_LIST pj_list[];
 #else
 #define PROJ_HEAD(id, name) \
     struct PJconsts *pj_##id(struct PJconsts*); extern char * const pj_s_##id;
-    
+
 #include "pj_list.h"
 #undef PROJ_HEAD
 #define PROJ_HEAD(id, name) {#id, pj_##id, &pj_s_##id},
@@ -350,7 +360,27 @@ extern struct PJ_PRIME_MERIDIANS pj_prime_meridians[];
 #define INVERSE3D(name) static LPZ name(XYZ xyz, PJ *P) {LPZ lpz = {0.0, 0.0, 0.0}
 #define FREEUP static void freeup(PJ *P) {
 #define SPECIAL(name) static void name(LP lp, PJ *P, struct FACTORS *fac)
+
+
+/* cleaned up alternative to most of the "repetitive projection code" macros */
+#define PROJECTION(name)                                     \
+pj_projection_specific_setup_##name (PJ *P);                 \
+C_NAMESPACE_VAR const char * const pj_s_##name = des_##name; \
+C_NAMESPACE PJ *pj_##name (PJ *P) {                          \
+    if (P)                                                   \
+        return pj_projection_specific_setup_##name (P);      \
+    P = (PJ*) pj_calloc (1, sizeof(PJ));                     \
+    if (0==P)                                                \
+        return 0;                                            \
+    P->pfree = freeup;                                       \
+    P->descr = des_##name;                                   \
+    return P;                                                \
+}                                                            \
+PJ *pj_projection_specific_setup_##name (PJ *P)
+
 #endif
+
+
 #define MAX_TAB_ID 80
 typedef struct { float lam, phi; } FLP;
 typedef struct { int lam, phi; } ILP;
@@ -366,8 +396,8 @@ struct CTABLE {
 typedef struct _pj_gi {
     char *gridname;   /* identifying name of grid, eg "conus" or ntv2_0.gsb */
     char *filename;   /* full path to filename */
-    
-    const char *format; /* format of this grid, ie "ctable", "ntv1", 
+
+    const char *format; /* format of this grid, ie "ctable", "ntv1",
                            "ntv2" or "missing". */
 
     int   grid_offset; /* offset in file, for delayed loading */
@@ -414,6 +444,7 @@ int pj_ell_set(projCtx ctx, paralist *, double *, double *);
 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 );
@@ -439,7 +470,7 @@ struct PW_COEF {/* row coefficient structure */
     int m;		/* number of c coefficients (=0 for none) */
     double *c;	/* power coefficients */
 };
- 
+
 /* Approximation structures and procedures */
 typedef struct {	/* Chebyshev or Power series structure */
 	projUV a, b;		/* power series range for evaluation */
@@ -457,6 +488,7 @@ void **vector2(int, int, int);
 void freev2(void **v, int nrows);
 int bchgen(projUV, projUV, int, int, projUV **, projUV(*)(projUV));
 int bch2bps(projUV, projUV, projUV **, int, int);
+
 /* nadcon related protos */
 LP nad_intr(LP, struct CTABLE *);
 LP nad_cvt(LP, int, struct CTABLE *);
@@ -470,15 +502,15 @@ void nad_free(struct CTABLE *);
 /* higher level handling of datum grid shift files */
 
 int pj_apply_vgridshift( PJ *defn, const char *listname,
-                         PJ_GRIDINFO ***gridlist_p, 
+                         PJ_GRIDINFO ***gridlist_p,
                          int *gridlist_count_p,
-                         int inverse, 
+                         int inverse,
                          long point_count, int point_offset,
                          double *x, double *y, double *z );
-int pj_apply_gridshift_2( PJ *defn, int inverse, 
+int pj_apply_gridshift_2( PJ *defn, int inverse,
                           long point_count, int point_offset,
                           double *x, double *y, double *z );
-int pj_apply_gridshift_3( projCtx ctx, 
+int pj_apply_gridshift_3( projCtx ctx,
                           PJ_GRIDINFO **gridlist, int gridlist_count,
                           int inverse, long point_count, int point_offset,
                           double *x, double *y, double *z );
@@ -493,15 +525,15 @@ void pj_gridinfo_free( projCtx, PJ_GRIDINFO * );
 PJ_GridCatalog *pj_gc_findcatalog( projCtx, const char * );
 PJ_GridCatalog *pj_gc_readcatalog( projCtx, const char * );
 void pj_gc_unloadall( projCtx );
-int pj_gc_apply_gridshift( PJ *defn, int inverse, 
+int pj_gc_apply_gridshift( PJ *defn, int inverse,
                            long point_count, int point_offset,
                            double *x, double *y, double *z );
-int pj_gc_apply_gridshift( PJ *defn, int inverse, 
+int pj_gc_apply_gridshift( PJ *defn, int inverse,
                            long point_count, int point_offset,
                            double *x, double *y, double *z );
 
-PJ_GRIDINFO *pj_gc_findgrid( projCtx ctx, 
-                             PJ_GridCatalog *catalog, int after, 
+PJ_GRIDINFO *pj_gc_findgrid( projCtx ctx,
+                             PJ_GridCatalog *catalog, int after,
                              LP location, double date,
                              PJ_Region *optional_region,
                              double *grid_date );