bes  Updated for version 3.20.13
HDFEOS5CFMissLLArray.cc
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1 // This file is part of the hdf5_handler implementing for the CF-compliant
2 // Copyright (c) 2011-2016 The HDF Group, Inc. and OPeNDAP, Inc.
3 //
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21 
31 
32 #include "config_hdf5.h"
33 #include <sys/stat.h>
34 #include <iostream>
35 #include <sstream>
36 #include <cassert>
37 #include <BESDebug.h>
38 #include <libdap/InternalErr.h>
39 //#include <libdap/Array.h>
40 
41 #include "HDFEOS5CFMissLLArray.h"
42 #include "HDF5RequestHandler.h"
43 
44 using namespace std;
45 using namespace libdap;
46 
47 BaseType *HDFEOS5CFMissLLArray::ptr_duplicate()
48 {
49  return new HDFEOS5CFMissLLArray(*this);
50 }
51 
52 bool HDFEOS5CFMissLLArray::read()
53 {
54 
55  BESDEBUG("h5","Coming to HDFEOS5CFMissLLArray read "<<endl);
56  if(nullptr == HDF5RequestHandler::get_lrdata_mem_cache())
57  read_data_NOT_from_mem_cache(false,nullptr);
58  else {
59  vector<string> cur_lrd_non_cache_dir_list;
60  HDF5RequestHandler::get_lrd_non_cache_dir_list(cur_lrd_non_cache_dir_list);
61 
62  string cache_key;
63  // Check if this file is included in the non-cache directory
64  if( (cur_lrd_non_cache_dir_list.empty()) ||
65  ("" == check_str_sect_in_list(cur_lrd_non_cache_dir_list,filename,'/'))) {
66  short cache_flag = 2;
67  vector<string> cur_cache_dlist;
68  HDF5RequestHandler::get_lrd_cache_dir_list(cur_cache_dlist);
69  string cache_dir = check_str_sect_in_list(cur_cache_dlist,filename,'/');
70  if(cache_dir != ""){
71  cache_key = cache_dir + varname;
72  cache_flag = 3;
73  }
74  else
75  cache_key = filename + varname;
76 
77  // Need to obtain the total number of elements.
78  // Currently only trivial geographic projection is supported.
79  // So the total number of elements for LAT is ydimsize,
80  // the total number of elements for LON is xdimsize.
81  if(cvartype == CV_LAT_MISS)
82  handle_data_with_mem_cache(H5FLOAT32,(size_t)ydimsize,cache_flag,cache_key,false);
83  else
84  handle_data_with_mem_cache(H5FLOAT32,(size_t)xdimsize,cache_flag,cache_key,false);
85  }
86  else
87  read_data_NOT_from_mem_cache(false,nullptr);
88  }
89  return true;
90 }
91 
92 void HDFEOS5CFMissLLArray::read_data_NOT_from_mem_cache(bool add_cache,void*buf){
93 
94  BESDEBUG("h5","Coming to read_data_NOT_from_mem_cache "<<endl);
95 
96  // First handle geographic projection. No GCTP is needed.Since the calculation
97  // of lat/lon is really simple for this case. No need to provide the disk cache
98  // unless the calculation takes too long. We will see.
99  if(eos5_projcode == HE5_GCTP_GEO) {
100  read_data_NOT_from_mem_cache_geo(add_cache,buf);
101  return;
102  }
103 
104  int nelms = -1;
105  vector<int>offset;
106  vector<int>count;
107  vector<int>step;
108 
109  if (rank <= 0)
110  throw InternalErr (__FILE__, __LINE__,
111  "The number of dimension of this variable should be greater than 0");
112  else {
113  offset.resize(rank);
114  count.resize(rank);
115  step.resize(rank);
116  nelms = format_constraint (offset.data(), step.data(), count.data());
117  }
118 
119  if (nelms <= 0)
120  throw InternalErr (__FILE__, __LINE__,
121  "The number of elments is negative.");
122 
123  vector<size_t>pos(rank,0);
124  for (int i = 0; i< rank; i++)
125  pos[i] = offset[i];
126 
127  vector<size_t>dimsizes;
128  dimsizes.push_back(ydimsize);
129  dimsizes.push_back(xdimsize);
130  int total_elms = xdimsize*ydimsize;
131 
132  double upleft[2];
133  double lowright[2];
134  vector<int>rows;
135  vector<int>cols;
136  vector<double>lon;
137  vector<double>lat;
138  rows.resize(xdimsize*ydimsize);
139  cols.resize(xdimsize*ydimsize);
140  lon.resize(xdimsize*ydimsize);
141  lat.resize(xdimsize*ydimsize);
142 
143  upleft[0] = point_left;
144  upleft[1] = point_upper;
145  lowright[0] = point_right;
146  lowright[1] = point_lower;
147 
148 
149  int j = 0;
150  int r = -1;
151 
152  for (int k = j = 0; j < ydimsize; ++j) {
153  for (int i = 0; i < xdimsize; ++i) {
154  rows[k] = j;
155  cols[k] = i;
156  ++k;
157  }
158  }
159 
160  BESDEBUG("h5", " Before calling GDij2ll, check all projection parameters. " << endl);
161  BESDEBUG("h5", " eos5_projcode is " << eos5_projcode <<endl);
162  BESDEBUG("h5", " eos5_zone is " << eos5_zone <<endl);
163  BESDEBUG("h5", " eos5_params[0] is " << eos5_params[0] <<endl);
164  BESDEBUG("h5", " eos5_params[1] is " << eos5_params[1] <<endl);
165  BESDEBUG("h5", " eos5_sphere is " << eos5_sphere <<endl);
166  BESDEBUG("h5", " xdimsize is " << xdimsize <<endl);
167  BESDEBUG("h5", " ydimsize is " << ydimsize <<endl);
168  BESDEBUG("h5", " eos5_pixelreg is " << eos5_pixelreg <<endl);
169  BESDEBUG("h5", " eos5_origin is " << eos5_origin <<endl);
170  BESDEBUG("h5", " upleft[0] is " << upleft[0] <<endl);
171  BESDEBUG("h5", " upleft[1] is " << upleft[1] <<endl);
172  BESDEBUG("h5", " lowright[0] is " << lowright[0] <<endl);
173  BESDEBUG("h5", " lowright[1] is " << lowright[1] <<endl);
174 
175 #if 0
176  cerr<< " eos5_params[0] is " << eos5_params[0] <<endl;
177  cerr<< " eos5_params[1] is " << eos5_params[1] <<endl;
178  cerr<< " eos5_sphere is " << eos5_sphere <<endl;
179  cerr<< " eos5_zone is " << eos5_zone <<endl;
180  cerr<< " Before calling GDij2ll, check all projection parameters. " << endl;
181  cerr<< " eos5_zone is " << eos5_zone <<endl;
182  cerr<< " eos5_params[0] is " << eos5_params[0] <<endl;
183  cerr<< " eos5_params[1] is " << eos5_params[1] <<endl;
184  BESDEBUG("h5", " xdimsize is " << xdimsize <<endl);
185  BESDEBUG("h5", " ydimsize is " << ydimsize <<endl);
186  BESDEBUG("h5", " eos5_pixelreg is " << eos5_pixelreg <<endl);
187  BESDEBUG("h5", " eos5_origin is " << eos5_origin <<endl);
188  BESDEBUG("h5", " upleft[0] is " << upleft[0] <<endl);
189  BESDEBUG("h5", " upleft[1] is " << upleft[1] <<endl);
190  BESDEBUG("h5", " lowright[0] is " << lowright[0] <<endl);
191  BESDEBUG("h5", " lowright[1] is " << lowright[1] <<endl);
192 #endif
193 
194  // boolean to mark if the value can be read from the cache.
195  // Not necessary from programming point of view. Use it to
196  // make the code flow clear.
197  bool ll_read_from_cache = true;
198 
199  // Check if geo-cache is turned on.
200  bool use_latlon_cache = HDF5RequestHandler::get_use_eosgeo_cachefile();
201 
202 
203  // Adding more code to read latlon from cache here.
204  if(use_latlon_cache == true) {
205 
206  // Cache name is made in a special way to make sure the same lat/lon
207  // fall into the same cache file.
208  string cache_fname = obtain_ll_cache_name();
209 
210  // Obtain eos-geo disk cache size, dir and prefix.
211  long ll_disk_cache_size = HDF5RequestHandler::get_latlon_disk_cache_size();
212  string ll_disk_cache_dir = HDF5RequestHandler::get_latlon_disk_cache_dir();
213  string ll_disk_cache_prefix = HDF5RequestHandler::get_latlon_disk_cachefile_prefix();
214 
215  // Expected cache file size
216  int expected_file_size = 2*xdimsize*ydimsize*sizeof(double);
217  HDF5DiskCache *ll_cache = HDF5DiskCache::get_instance(ll_disk_cache_size,ll_disk_cache_dir,ll_disk_cache_prefix);
218  int fd = 0;
219  ll_read_from_cache = ll_cache->get_data_from_cache(cache_fname, expected_file_size,fd);
220 
221  if(ll_read_from_cache == true) {
222 
223  BESDEBUG("h5", " Read latitude and longitude from a disk cache. " <<endl);
224  size_t var_offset = 0;
225  // Longitude is stored after latitude.
226  if(CV_LON_MISS == cvartype)
227  var_offset = xdimsize*ydimsize*sizeof(double);
228 
229  vector<double> var_value;
230  var_value.resize(xdimsize*ydimsize);
231 
232 #if 0
233  //Latitude starts from 0, longitude starts from xdimsize*ydimsize*sizeof(double);
234 #endif
235  off_t fpos = lseek(fd,var_offset,SEEK_SET);
236  if(fpos == -1) {
237  throw InternalErr (__FILE__, __LINE__,
238  "Cannot seek the cached file offset.");
239 
240  }
241  ssize_t ret_val = HDF5CFUtil::read_buffer_from_file(fd,(void*)var_value.data(),var_value.size()*sizeof(double));
242  ll_cache->unlock_and_close(cache_fname);
243 
244  // If the cached file is not read correctly, we should purge the file.
245  if((-1 == ret_val) || ((size_t)ret_val != (xdimsize*ydimsize*sizeof(double)))) {
246  ll_cache->purge_file(cache_fname);
247  ll_read_from_cache = false;
248  }
249  else {
250  // short-cut, no need to do subset.
251  if(total_elms == nelms)
252  set_value((dods_float64 *)var_value.data(),total_elms);
253  else {
254  vector<double>val;
255  subset<double>(
256  var_value.data(),
257  rank,
258  dimsizes,
259  offset.data(),
260  step.data(),
261  count.data(),
262  &val,
263  pos,
264  0);
265  set_value((dods_float64 *)val.data(),nelms);
266  }
267  return;
268  }
269  }
270  else
271  ll_read_from_cache = false;
272  }
273 
274  // Calculate Lat/lon by using GCTP
275  r = GDij2ll (eos5_projcode, eos5_zone, eos5_params.data(), eos5_sphere, xdimsize, ydimsize, upleft, lowright,
276  xdimsize * ydimsize, rows.data(), cols.data(), lon.data(), lat.data(), eos5_pixelreg, eos5_origin);
277  if (r != 0) {
278  ostringstream eherr;
279  eherr << "cannot calculate grid latitude and longitude";
280  throw InternalErr (__FILE__, __LINE__, eherr.str ());
281  }
282 
283 
284  // ll_read_from_cache may be redundant. It is good to remind that we will generate the cache file
285  // when reading from the cache fails.
286  // We are using cache and need to write data to the cache.
287  if(use_latlon_cache == true && ll_read_from_cache == false) {
288  string cache_fname = obtain_ll_cache_name();
289  long ll_disk_cache_size = HDF5RequestHandler::get_latlon_disk_cache_size();
290  string ll_disk_cache_dir = HDF5RequestHandler::get_latlon_disk_cache_dir();
291  string ll_disk_cache_prefix = HDF5RequestHandler::get_latlon_disk_cachefile_prefix();
292 
293  BESDEBUG("h5", " Write EOS5 grid latitude and longitude to a disk cache. " <<endl);
294 
295  HDF5DiskCache *ll_cache = HDF5DiskCache::get_instance(ll_disk_cache_size,ll_disk_cache_dir,ll_disk_cache_prefix);
296 
297  // Merge vector lat and lon. lat first.
298  vector <double>latlon;
299  latlon.reserve(xdimsize*ydimsize*2);
300  latlon.insert(latlon.end(),lat.begin(),lat.end());
301  latlon.insert(latlon.end(),lon.begin(),lon.end());
302  ll_cache->write_cached_data(cache_fname,2*xdimsize*ydimsize*sizeof(double),latlon);
303 
304  }
305  BESDEBUG("h5", " The first value of lon is " << lon[0] <<endl);
306  BESDEBUG("h5", " The first value of lat is " << lat[0] <<endl);
307 
308 #if 0
309  vector<size_t>pos(rank,0);
310  for (int i = 0; i< rank; i++)
311  pos[i] = offset[i];
312 
313  vector<size_t>dimsizes;
314  dimsizes.push_back(ydimsize);
315  dimsizes.push_back(xdimsize);
316  int total_elms = xdimsize*ydimsize;
317 #endif
318 
319 
320  if(CV_LON_MISS == cvartype) {
321  if(total_elms == nelms)
322  set_value((dods_float64 *)lon.data(),total_elms);
323  else {
324  vector<double>val;
325  subset<double>(
326  lon.data(),
327  rank,
328  dimsizes,
329  offset.data(),
330  step.data(),
331  count.data(),
332  &val,
333  pos,
334  0);
335  set_value((dods_float64 *)val.data(),nelms);
336  }
337 
338  }
339  else if(CV_LAT_MISS == cvartype) {
340 
341  if(total_elms == nelms)
342  set_value((dods_float64 *)lat.data(),total_elms);
343  else {
344  vector<double>val;
345  subset<double>(
346  lat.data(),
347  rank,
348  dimsizes,
349  offset.data(),
350  step.data(),
351  count.data(),
352  &val,
353  pos,
354  0);
355  set_value((dods_float64 *)val.data(),nelms);
356  }
357  }
358  return;
359 
360 }
361 
362 string HDFEOS5CFMissLLArray::obtain_ll_cache_name() {
363 
364  BESDEBUG("h5","Coming to obtain_ll_cache_name "<<endl);
365 
366 
367  // Here we have a sanity check for the cached parameters:Cached directory,file prefix and cached directory size.
368  // Supposedly Hyrax BES cache feature should check this and the code exists. However, the
369  string bescachedir = HDF5RequestHandler::get_latlon_disk_cache_dir();
370  string bescacheprefix = HDF5RequestHandler::get_latlon_disk_cachefile_prefix();
371  long cachesize = HDF5RequestHandler::get_latlon_disk_cache_size();
372 
373  if(("" == bescachedir)||(""==bescacheprefix)||(cachesize <=0)){
374  throw InternalErr (__FILE__, __LINE__, "Either the cached dir is empty or the prefix is nullptr or the cache size is not set.");
375  }
376  else {
377  struct stat sb;
378  if(stat(bescachedir.c_str(),&sb) !=0) {
379  string err_mesg="The cached directory " + bescachedir;
380  err_mesg = err_mesg + " doesn't exist. ";
381  throw InternalErr(__FILE__,__LINE__,err_mesg);
382 
383  }
384  else {
385  if(true == S_ISDIR(sb.st_mode)) {
386  if(access(bescachedir.c_str(),R_OK|W_OK|X_OK) == -1) {
387  string err_mesg="The cached directory " + bescachedir;
388  err_mesg = err_mesg + " can NOT be read,written or executable.";
389  throw InternalErr(__FILE__,__LINE__,err_mesg);
390  }
391  }
392  else {
393  string err_mesg="The cached directory " + bescachedir;
394  err_mesg = err_mesg + " is not a directory.";
395  throw InternalErr(__FILE__,__LINE__,err_mesg);
396  }
397  }
398  }
399 
400  string cache_fname=HDF5RequestHandler::get_latlon_disk_cachefile_prefix();
401 
402  // Projection code,zone,sphere,pix,origin
403  cache_fname +=HDF5CFUtil::get_int_str(eos5_projcode);
404  cache_fname +=HDF5CFUtil::get_int_str(eos5_zone);
405  cache_fname +=HDF5CFUtil::get_int_str(eos5_sphere);
406  cache_fname +=HDF5CFUtil::get_int_str(eos5_pixelreg);
407  cache_fname +=HDF5CFUtil::get_int_str(eos5_origin);
408 
409  cache_fname +=HDF5CFUtil::get_int_str(ydimsize);
410  cache_fname +=HDF5CFUtil::get_int_str(xdimsize);
411 
412  // upleft,lowright
413  // HDF-EOS upleft,lowright,params use DDDDMMMSSS.6 digits. So choose %17.6f.
414  cache_fname +=HDF5CFUtil::get_double_str(point_left,17,6);
415  cache_fname +=HDF5CFUtil::get_double_str(point_upper,17,6);
416  cache_fname +=HDF5CFUtil::get_double_str(point_right,17,6);
417  cache_fname +=HDF5CFUtil::get_double_str(point_lower,17,6);
418 
419  // According to HDF-EOS2 document, only 13 parameters are used.
420  for(int ipar = 0; ipar<13;ipar++) {
421  cache_fname+=HDF5CFUtil::get_double_str(eos5_params[ipar],17,6);
422  }
423 
424  string cache_fpath = bescachedir + "/"+ cache_fname;
425  return cache_fpath;
426 
427 }
428 void HDFEOS5CFMissLLArray::read_data_NOT_from_mem_cache_geo(bool add_cache,void*buf){
429 
430  BESDEBUG("h5","Coming to read_data_NOT_from_mem_cache_geo "<<endl);
431  int nelms = -1;
432  vector<int>offset;
433  vector<int>count;
434  vector<int>step;
435 
436 
437  if (rank <= 0)
438  throw InternalErr (__FILE__, __LINE__,
439  "The number of dimension of this variable should be greater than 0");
440  else {
441 
442  offset.resize(rank);
443  count.resize(rank);
444  step.resize(rank);
445  nelms = format_constraint (offset.data(), step.data(), count.data());
446  }
447 
448  if (nelms <= 0)
449  throw InternalErr (__FILE__, __LINE__,
450  "The number of elments is negative.");
451 
452  float start = 0.0;
453  float end = 0.0;
454 
455  vector<float>val;
456  val.resize(nelms);
457 
458 
459  if (CV_LAT_MISS == cvartype) {
460 
461  if (HE5_HDFE_GD_UL == eos5_origin || HE5_HDFE_GD_UR == eos5_origin) {
462 
463  start = point_upper;
464  end = point_lower;
465 
466  }
467  else {// (gridorigin == HE5_HDFE_GD_LL || gridorigin == HE5_HDFE_GD_LR)
468 
469  start = point_lower;
470  end = point_upper;
471  }
472 
473  if(ydimsize <=0)
474  throw InternalErr (__FILE__, __LINE__,
475  "The number of elments should be greater than 0.");
476 
477  float lat_step = (end - start) /ydimsize;
478 
479  // Now offset,step and val will always be valid. line 74 and 85 assure this.
480  if ( HE5_HDFE_CENTER == eos5_pixelreg ) {
481  for (int i = 0; i < nelms; i++)
482  val[i] = ((offset[0]+i*step[0] + 0.5F) * lat_step + start) / 1000000.0F;
483 
484  // If the memory cache is turned on, we have to save all values to the buf
485  if(add_cache == true) {
486  vector<float>total_val;
487  total_val.resize(ydimsize);
488  for (int total_i = 0; total_i < ydimsize; total_i++)
489  total_val[total_i] = ((total_i + 0.5F) * lat_step + start) / 1000000.0F;
490  // Note: the float is size 4
491  memcpy(buf,total_val.data(),4*ydimsize);
492  }
493 
494  }
495  else { // HE5_HDFE_CORNER
496  for (int i = 0; i < nelms; i++)
497  val[i] = ((float)(offset[0]+i * step[0])*lat_step + start) / 1000000.0F;
498 
499  // If the memory cache is turned on, we have to save all values to the buf
500  if(add_cache == true) {
501  vector<float>total_val;
502  total_val.resize(ydimsize);
503  for (int total_i = 0; total_i < ydimsize; total_i++)
504  total_val[total_i] = ((float)(total_i) * lat_step + start) / 1000000.0F;
505  // Note: the float is size 4
506  memcpy(buf,total_val.data(),4*ydimsize);
507  }
508 
509  }
510  }
511 
512  if (CV_LON_MISS == cvartype) {
513 
514  if (HE5_HDFE_GD_UL == eos5_origin || HE5_HDFE_GD_LL == eos5_origin) {
515 
516  start = point_left;
517  end = point_right;
518 
519  }
520  else {// (gridorigin == HE5_HDFE_GD_UR || gridorigin == HE5_HDFE_GD_LR)
521 
522  start = point_right;
523  end = point_left;
524  }
525 
526  if(xdimsize <=0)
527  throw InternalErr (__FILE__, __LINE__,
528  "The number of elments should be greater than 0.");
529  float lon_step = (end - start) /xdimsize;
530 
531  if (HE5_HDFE_CENTER == eos5_pixelreg) {
532  for (int i = 0; i < nelms; i++)
533  val[i] = ((offset[0] + i *step[0] + 0.5F) * lon_step + start ) / 1000000.0F;
534 
535  // If the memory cache is turned on, we have to save all values to the buf
536  if(add_cache == true) {
537  vector<float>total_val;
538  total_val.resize(xdimsize);
539  for (int total_i = 0; total_i < xdimsize; total_i++)
540  total_val[total_i] = ((total_i+0.5F) * lon_step + start) / 1000000.0F;
541  // Note: the float is size 4
542  memcpy(buf,total_val.data(),4*xdimsize);
543  }
544 
545  }
546  else { // HE5_HDFE_CORNER
547  for (int i = 0; i < nelms; i++)
548  val[i] = ((float)(offset[0]+i*step[0]) * lon_step + start) / 1000000.0F;
549 
550  // If the memory cache is turned on, we have to save all values to the buf
551  if(add_cache == true) {
552  vector<float>total_val;
553  total_val.resize(xdimsize);
554  for (int total_i = 0; total_i < xdimsize; total_i++)
555  total_val[total_i] = ((float)(total_i) * lon_step + start) / 1000000.0F;
556  // Note: the float is size 4
557  memcpy(buf,total_val.data(),4*xdimsize);
558  }
559  }
560  }
561 
562 #if 0
563 for (int i =0; i <nelms; i++)
564 "h5","final data val "<< i <<" is " << val[i] <<endl;
565 #endif
566 
567  set_value ((dods_float32 *) val.data(), nelms);
568 
569 
570  return;
571 }
572 
573 #if 0
574 // parse constraint expr. and make hdf5 coordinate point location.
575 // return number of elements to read.
576 int
577 HDFEOS5CFMissLLArray::format_constraint (int *offset, int *step, int *count)
578 {
579  long nels = 1;
580  int id = 0;
581 
582  Dim_iter p = dim_begin ();
583 
584  while (p != dim_end ()) {
585 
586  int start = dimension_start (p, true);
587  int stride = dimension_stride (p, true);
588  int stop = dimension_stop (p, true);
589 
590  // Check for illegal constraint
591  if (start > stop) {
592  ostringstream oss;
593 
594  oss << "Array/Grid hyperslab start point "<< start <<
595  " is greater than stop point " << stop <<".";
596  throw Error(malformed_expr, oss.str());
597  }
598 
599 
600 
601  offset[id] = start;
602  step[id] = stride;
603  count[id] = ((stop - start) / stride) + 1; // count of elements
604  nels *= count[id]; // total number of values for variable
605 
606  BESDEBUG ("h5",
607  "=format_constraint():"
608  << "id=" << id << " offset=" << offset[id]
609  << " step=" << step[id]
610  << " count=" << count[id]
611  << endl);
612 
613  id++;
614  p++;
615  }
616 
617  return nels;
618 }
619 
620 #endif
include the entry functions to execute the handlers
This class specifies the retrieval of the missing lat/lon values for HDF-EOS5 products.
static HDF5DiskCache * get_instance(const long, const std::string &, const std::string &)
static ssize_t read_buffer_from_file(int fd, void *buf, size_t)
Getting a subset of a variable.
Definition: HDF5CFUtil.cc:1194