Read arbitrary GRIB keys

ChangeLog

@@ -3,6 +3,10 @@
 	* Version 1.6.0 released
 	* using CGRIBEX library version 1.6.0
 
+2013-03-13  Florian Prill  <Florian.Prill@dwd.de>
+
+	* Read arbitrary GRIB keys [Feature #3267]
+
 2013-03-13  Uwe Schulzweida  <Uwe.Schulzweida@zmaw.de>
 
 	* GRIB: added support for time step unit: seconds (Bug #3352)

doc/tex/c_quick_ref.tex

@@ -939,6 +939,24 @@ Get the name of a Variable.
 Get the parameter number of a Variable.
 
 
+\section*{\tt \htmlref{vlistInqVarRawBegin}{vlistInqVarRawBegin}}
+
+\begin{verbatim}
+    void vlistInqVarRawBegin (int streamID, int varID);
+\end{verbatim}
+
+Open GRIB record to retrieve raw meta-data in subsequent calls.
+
+
+\section*{\tt \htmlref{vlistInqVarRawEnd}{vlistInqVarRawEnd}}
+
+\begin{verbatim}
+    void vlistInqVarRawEnd (int streamID);
+\end{verbatim}
+
+Free previously opened GRIB record.
+
+
 \section*{\tt \htmlref{vlistInqVarStdname}{vlistInqVarStdname}}
 
 \begin{verbatim}

doc/tex/f_quick_ref.tex

@@ -955,6 +955,24 @@ Get the name of a Variable.
 Get the parameter number of a Variable.
 
 
+\section*{\tt \htmlref{vlistInqVarRawBegin}{vlistInqVarRawBegin}}
+
+\begin{verbatim}
+    SUBROUTINE vlistInqVarRawBegin (INTEGER streamID, INTEGER varID)
+\end{verbatim}
+
+Open GRIB record to retrieve raw meta-data in subsequent calls.
+
+
+\section*{\tt \htmlref{vlistInqVarRawEnd}{vlistInqVarRawEnd}}
+
+\begin{verbatim}
+    SUBROUTINE vlistInqVarRawEnd (INTEGER streamID)
+\end{verbatim}
+
+Free previously opened GRIB record.
+
+
 \section*{\tt \htmlref{vlistInqVarStdname}{vlistInqVarStdname}}
 
 \begin{verbatim}

src/cdi.h

@@ -537,6 +537,20 @@ void    vlistDefVarIntKey(int vlistID, int varID, const char *name, int value);
 /* vlistDefVarDblKey: Set an arbitrary keyword/double value pair for GRIB API */
 void    vlistDefVarDblKey(int vlistID, int varID, const char *name, double value);
 
+  /* ---------------------------------- */
+  /* Local change: 2013-02-18, FP (DWD) */
+  /* ---------------------------------- */
+
+/* vlistInqVarRawBegin: Open GRIB record to retrieve raw meta-data in subsequent calls */
+void    vlistInqVarRawBegin(int streamID, int varID);
+/* vlistInqVarDblKey: raw access to GRIB meta-data */
+double  vlistInqVarDblKey(int streamID, const char* name);
+/* vlistInqVarIntKey: raw access to GRIB meta-data */
+int     vlistInqVarIntKey(int streamID, const char* name);
+/* vlistInqVarRawEnd: Free previously opened GRIB record */
+void    vlistInqVarRawEnd(int streamID);
+
+
 /* VLIST attributes */
 
 /*      vlistInqNatts: Get number of variable attributes assigned to this variable */

src/cdi.inc

@@ -1206,6 +1206,24 @@
 !                                     DOUBLEPRECISION value)
       EXTERNAL        vlistDefVarDblKey
 
+!
+!  ----------------------------------
+!
+!
+!  Local change: 2013-02-18, FP (DWD)
+!
+!
+!  ----------------------------------
+!
+!                     vlistInqVarRawBegin
+!                                    (INTEGER         streamID,
+!                                     INTEGER         varID)
+      EXTERNAL        vlistInqVarRawBegin
+
+!                     vlistInqVarRawEnd
+!                                    (INTEGER         streamID)
+      EXTERNAL        vlistInqVarRawEnd
+
 !
 !  VLIST attributes
 !

src/cdiFortran.c

@@ -259,6 +259,17 @@ FCALLSCFUN5 (INT, vlistInqVarEnsemble, VLISTINQVARENSEMBLE, vlistinqvarensemble,
 FCALLSCSUB4 (vlistDefVarIntKey, VLISTDEFVARINTKEY, vlistdefvarintkey, INT, INT, STRING, INT)
 FCALLSCSUB4 (vlistDefVarDblKey, VLISTDEFVARDBLKEY, vlistdefvardblkey, INT, INT, STRING, DOUBLE)
 
+/*  ----------------------------------  */
+
+
+/*  Local change: 2013-02-18, FP (DWD)  */
+
+
+/*  ----------------------------------  */
+
+FCALLSCSUB2 (vlistInqVarRawBegin, VLISTINQVARRAWBEGIN, vlistinqvarrawbegin, INT, INT)
+FCALLSCSUB1 (vlistInqVarRawEnd, VLISTINQVARRAWEND, vlistinqvarrawend, INT)
+
 /*  VLIST attributes  */
 
 FCALLSCFUN3 (INT, vlistInqNatts, VLISTINQNATTS, vlistinqnatts, INT, INT, PINT)

src/stream_grb.c

@@ -348,7 +348,7 @@ void grbReadVarDP(stream_t * streamptr, int varID, double *data, int *nmiss)
 
       missval = vlistInqVarMissval(vlistID, varID);
 
-      grbDecode(filetype, gribbuffer, recsize, &data[levelID*gridsize], gridsize, 
+      grbDecode(filetype, gribbuffer, recsize, &data[levelID*gridsize], gridsize,
 		streamptr->unreduced, &imiss, &zip, missval);
 
       *nmiss += imiss;

src/stream_int.h

@@ -251,6 +251,12 @@ typedef struct {
   void       *gribContainers;
 #endif
   int         vlistIDorig;
+
+  /* ---------------------------------- */
+  /* Local change: 2013-02-18, FP (DWD) */
+  /* ---------------------------------- */
+
+  void *gh; // grib handle
 }
 stream_t;
 

src/vlist_var.c

@@ -674,7 +674,7 @@ void vlistInqVarStdname(int vlistID, int varID, char *stdname)
   if ( vlistptr->vars[varID].stdname == NULL )
     {
       stdname[0] = '\0';
-    }  
+    }
   else
     strcpy(stdname, vlistptr->vars[varID].stdname);
 
@@ -689,7 +689,7 @@ void vlistInqVarStdname(int vlistID, int varID, char *stdname)
 @Parameter
     @Item  vlistID  Variable list ID, from a previous call to @fref{vlistCreate}.
     @Item  varID    Variable identifier.
-    @Item  units    Units of the variable. The caller must allocate space for the 
+    @Item  units    Units of the variable. The caller must allocate space for the
                     returned string. The maximum possible length, in characters, of
                     the string is given by the predefined constant @func{CDI_MAX_NAME}.
 
@@ -1848,6 +1848,74 @@ void vlistDefVarDblKey(int vlistID, int varID, const char *name, double value)
     Error("Internal error!");
 }
 
+#if  defined  (HAVE_LIBGRIB_API)
+#  include "file.h"
+#  include "grib_api.h"
+#endif
+
+/* vlistInqVarRawBegin: Open GRIB record to retrieve raw meta-data in subsequent calls */
+void vlistInqVarRawBegin(int streamID, int varID)
+{
+#if  defined  (HAVE_LIBGRIB_API)
+  stream_t *streamptr;
+  int       recID, tsID, fileID;
+  long      recpos, recsize;
+
+  streamptr = stream_to_pointer(streamID);
+  stream_check_ptr(__func__, streamptr);
+
+  fileID  = streamInqFileID(streamID);
+  tsID    = streamptr->curTsID;
+
+  // determine record ID for varID in current time step
+  for (recID=0; (recID<streamptr->tsteps[0].nrecs) && (varID != streamptr->tsteps[tsID].records[recID].varID); recID++);
+  recpos  = streamptr->tsteps[tsID].records[recID].position;
+  recsize = streamptr->tsteps[tsID].records[recID].size;
+
+  fileSetPos(fileID, recpos, SEEK_SET);
+  fileRead(fileID, streamptr->record->buffer, (size_t) recsize);
+
+  streamptr->gh = (void *) grib_handle_new_from_message(NULL, (void *) streamptr->record->buffer, recsize);
+#endif
+}
+
+
+/* vlistInqVarDblKey: raw access to GRIB meta-data */
+double vlistInqVarDblKey(int streamID, const char* name)
+{
+  double value = 0;
+#if  defined  (HAVE_LIBGRIB_API)
+  stream_t *streamptr = stream_to_pointer(streamID);
+  stream_check_ptr(__func__, streamptr);
+  GRIB_CHECK(grib_get_double((grib_handle*) streamptr->gh, name, &value), 0);
+#endif
+  return value;
+}
+
+
+/* vlistInqVarIntKey: raw access to GRIB meta-data */
+int vlistInqVarIntKey(int streamID, const char* name)
+{
+  long int value = 0;
+#if  defined  (HAVE_LIBGRIB_API)
+  stream_t *streamptr = stream_to_pointer(streamID);
+  stream_check_ptr(__func__, streamptr);
+  GRIB_CHECK(grib_get_long((grib_handle*) streamptr->gh, name, &value), 0);
+#endif
+  return (int) value;
+}
+
+
+/* vlistInqVarRawEnd: Free previously opened GRIB record */
+void vlistInqVarRawEnd(int streamID)
+{
+#if  defined  (HAVE_LIBGRIB_API)
+  stream_t *streamptr = stream_to_pointer(streamID);
+  stream_check_ptr(__func__, streamptr);
+  grib_handle_delete((grib_handle*) streamptr->gh);
+#endif
+}
+
 
 void vlistDefVarDeco ( int vlistID, int varID, int decoSize, deco_t * deco )
 {