datum.h

Go to the documentation of this file.

/* Copyright (C) 2017 Chris Piker <chris-piker@uiowa.edu>
 *
 * This file is part of das2C, the Core Das2 C Library.
 * 
 * Das2C is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License version 2.1 as published
 * by the Free Software Foundation.
 *
 * Das2C is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
 * more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 2.1 along with das2C; if not, see <http://www.gnu.org/licenses/>. 
 */
 
#ifndef _das_datum_h_
#define _das_datum_h_
 
#include <das3/value.h>
#include <das3/units.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
/* Sized for the largest value that lives inline: a das_time.  
   A composite objects point to external data, and the object needed
   to interpret them */
#define DATUM_BUF_SZ 32
   
struct das_form;   /* opaque here; datum.c never dereferences one */
 
/* The vtComposite box -- its struct and its bit layout -- is private to
   datum.c.  Unlike a das_time or a double, which a caller may reasonably cast
   a datum pointer to, a composite is not a value you read by looking at it:
   the extents live in two places depending on size, and the run belongs to
   whoever supplied it.  Use the accessors below.  Nothing is lost by hiding
   it and the representation stays free to change. */
 
 
typedef struct datum_t {
   ubyte bytes[DATUM_BUF_SZ]; /* 32 bytes of space */
   das_val_type vt;
   uint32_t vsize;
   das_units units;
} das_datum;
 
DAS_API void das_datum_init(
   das_datum* pThis, const ubyte* pSrc, das_val_type vt, uint32_t vsize, 
   das_units units
);
 
DAS_API das_val_type das_datum_elemType(const das_datum* pThis);
 
DAS_API bool das_datum_box(
   das_datum* pThis, const struct das_form* pForm, const ubyte* pRun,
   int nRank, const ptrdiff_t* pShape, das_val_type et, das_units units
);
 
DAS_API const struct das_form* das_datum_form(const das_datum* pThis);
 
DAS_API const ubyte* das_datum_run(const das_datum* pThis);
 
DAS_API int das_datum_shape(const das_datum* pThis, ptrdiff_t* pShape);
 
DAS_API size_t das_datum_nElems(const das_datum* pThis);
 
DAS_API size_t das_datum_runBytes(const das_datum* pThis);
 
#define das_datum_valid(p) ((p)->vsize > 0)
 
#define das_datum_islocal(p) \
   ( ((p)->vt >= VT_MIN_LOCAL) && ((p)->vt <= VT_MAX_LOCAL) )
 
 
DAS_API bool das_datum_fromStr(das_datum* pThis, const char* sStr);
 
DAS_API bool das_datum_fromDbl(das_datum* pThis, double value, das_units units);
 
DAS_API bool das_datum_wrapStr(das_datum* pTHis, const char* sStr, das_units units);
 
 
DAS_API bool das_datum_byteSeq(
   das_datum* pThis, das_cbyte_seq seq, das_units units
);
 
DAS_API char* das_datum_toStr(
   const das_datum* pThis, char* sStr, size_t uLen, int nFracDigits
);
 
DAS_API char* das_datum_toStrValOnly(
   const das_datum* pThis, char* sStr, size_t uLen, int nFracDigits
);
 
DAS_API char* das_datum_toStrValOnlySep(
   const das_datum* pThis, char* sStr, size_t uLen, int nFracDigits, 
   const char* sSep
);
 
 
DAS_API bool das_datum_toDbl(const das_datum* pThis, double* pOut);
 
DAS_API int das_datum_toDoubles(
   const das_datum* pThis, double* pOut, int nMax
);
 
 
DAS_API bool das_datum_toEpoch(
   const das_datum* pThis, das_units epoch, double* pResult
);
 
DAS_API bool das_datum_toTime(const das_datum* pThis, das_time* pDt);
 
 
#define das_datum_asStr(dm) *((char**)&dm)
 
#ifdef __cplusplus
}
#endif
 
#endif   /* _das_datum_h_ */