MtkFieldAttrList.c

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/*===========================================================================
=                                                                           =
=                             MtkFieldAttrList                              =
=                                                                           =
=============================================================================

                         Jet Propulsion Laboratory
                                   MISR
                               MISR Toolkit

            Copyright 2006, California Institute of Technology.
                           ALL RIGHTS RESERVED.
                 U.S. Government Sponsorship acknowledged.

============================================================================*/

#include "MisrFileQuery.h"
#include "MisrError.h"
#include <mfhdf.h>
#include <HdfEosDef.h>
#include <stdlib.h>
#include <string.h>

MTKt_status MtkFieldAttrList(
  const char *filename,    
  const char *fieldname,    
  int *num_attrs,          
  char **attrlist[]         )
{
  MTKt_status status;      /* Return status */

  status = MtkFieldAttrListNC(filename, fieldname, num_attrs, attrlist); // try netCDF
  if (status != MTK_NETCDF_OPEN_FAILED) return status;

  return MtkFieldAttrListHDF(filename, fieldname, num_attrs, attrlist); // try HDF
}

MTKt_status MtkFieldAttrListNC(
  const char *filename,    
  const char *fieldname,    
  int *num_attrs,          
  char **attrlist[]         )
{
  MTKt_status status_code; /* Return status of this function */
  MTKt_status status;      /* Return status */

  if (filename == NULL) return MTK_NULLPTR;

  /* Open file */
  int ncid = 0;
  {
    int nc_status = nc_open(filename, NC_NOWRITE, &ncid);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_OPEN_FAILED);
  }

  /* Read grid attribute */
  status = MtkFieldAttrListNcid(ncid, fieldname, num_attrs, attrlist);
  MTK_ERR_COND_JUMP(status);

  /* Close file */
  {
    int nc_status = nc_close(ncid);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_CLOSE_FAILED);
  }
  ncid = 0;

  return MTK_SUCCESS;

 ERROR_HANDLE:
  if (ncid != 0) nc_close(ncid);
  return status_code;
}


MTKt_status MtkFieldAttrListHDF(
  const char *filename,    
  const char *fieldname,    
  int *num_attrs,          
  char **attrlist[]         )
{
  MTKt_status status_code; /* Return status of this function */
  MTKt_status status;      /* Return status */
  int32 hdfstatus;         /* HDF-EOS return status */
  int32 fid = FAIL;    /* HDF-EOS File id */

  if (filename == NULL)
    MTK_ERR_CODE_JUMP(MTK_NULLPTR);

  /* Open HDF File */
  fid = GDopen((char*)filename, DFACC_READ);
  if (fid == FAIL)
    MTK_ERR_CODE_JUMP(MTK_HDFEOS_GDOPEN_FAILED);

  /* Get list of field attributes. */
  status = MtkFieldAttrListFid(fid, fieldname, num_attrs, attrlist);
  MTK_ERR_COND_JUMP(status);

  /* Close HDF file */
  hdfstatus = GDclose(fid);
  if (hdfstatus == FAIL)
    MTK_ERR_CODE_JUMP(MTK_HDFEOS_GDCLOSE_FAILED);
  fid = FAIL;

  return MTK_SUCCESS;

ERROR_HANDLE:
  if (fid != FAIL)
    GDclose(fid);

  return status_code;
}

MTKt_status MtkFieldAttrListFid(
  int32 fid,               
  const char *fieldname,    
  int *num_attrs,          
  char **attrlist[]         )
{
  MTKt_status status_code;     /* Return status of this function */
  int32 n_attrs = 0;           /* Number of attributes */
  int32 count;                 /* Number of values in attribute */
  int32 HDFfid = FAIL;         /* HDF File ID */
  int32 sdInterfaceID = FAIL;  /* SD Interface ID (file level) */
  int32 sd_id = FAIL;          /* SDS ID (field level) */
  int32 sds_index = 0;         /* SDS index/offset for field */  
  int32 rank;                  /* Number of dimensions for field */
  int32 data_type;             /* Field data type */
  char name[H4_MAX_NC_NAME];      /* SDS field name */
  intn hdf_status;             /* HDF return status */
  char attr_name[H4_MAX_NC_NAME]; /* Name of attribute */
  int32 attr_index = 0;        /* Index of attribute */
  int32 hdf_datatype;          /* Attribute data type */
  char **attrlist_tmp = NULL;  
  int32 dim_sizes[H4_MAX_VAR_DIMS];
 
  if (fieldname == NULL || 
      num_attrs == NULL || attrlist == NULL)
    MTK_ERR_CODE_JUMP(MTK_NULLPTR);

  /* Transform HDF-EOS fid to plain HDF fid and SDS fid for file */  
  EHidinfo(fid, &HDFfid, &sdInterfaceID);  
  
  sds_index = SDnametoindex(sdInterfaceID, fieldname);
  sd_id = SDselect(sdInterfaceID,sds_index);  
  SDgetinfo(sd_id, name, &rank, dim_sizes, &data_type, &n_attrs);
  
  attrlist_tmp = (char**)calloc(n_attrs,sizeof(char**));
  if (attrlist_tmp == NULL)
    MTK_ERR_CODE_JUMP(MTK_CALLOC_FAILED); 
  
  for (attr_index = 0; attr_index < n_attrs; ++attr_index)
  {
    /* Get attribute information */
    hdf_status = SDattrinfo(sd_id, attr_index, attr_name, &hdf_datatype, &count);
    if (hdf_status == FAIL)
      MTK_ERR_CODE_JUMP(MTK_HDF_SDATTRINFO_FAILED);

    attrlist_tmp[attr_index] = (char*)malloc((strlen(attr_name) + 1) * sizeof(char));
    if (attrlist_tmp[attr_index] == NULL)
      MTK_ERR_CODE_JUMP(MTK_MALLOC_FAILED);

    strcpy(attrlist_tmp[attr_index],attr_name);
  }
  *attrlist = attrlist_tmp;
  *num_attrs = n_attrs;
  return MTK_SUCCESS;
  
  
ERROR_HANDLE:
  if (attrlist_tmp != NULL)
    MtkStringListFree(n_attrs, &attrlist_tmp);

  if (num_attrs != NULL)
    *num_attrs = -1;

  return status_code;
}

MTKt_status MtkFieldAttrListNcid(
  int ncid,               
  const char *fieldname,    
  int *num_attrs,          
  char **attrlist[]         )
{
  MTKt_status status_code;     /* Return status of this function */
  char **attrlist_tmp = NULL;  
  int *gids = NULL;
 
  if (fieldname == NULL || 
      num_attrs == NULL || attrlist == NULL)
    MTK_ERR_CODE_JUMP(MTK_NULLPTR);

  /* Iterate over groups and fields until fieldname matches.  Only the first match will be tried. */
  MTKt_ncvarid var;
  int found = 0;
  {
    int number_group;
    int nc_status = nc_inq_grps(ncid, &number_group, NULL);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_READ_FAILED);
    
    gids = (int *)calloc(number_group, sizeof(int));
    if (gids == NULL) MTK_ERR_CODE_JUMP(MTK_CALLOC_FAILED);

    nc_status = nc_inq_grps(ncid, &number_group, gids);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_READ_FAILED);

    for (int i = 0 ; i < number_group ; i++) {
      int gid = gids[i];

      int status = MtkNCVarId(gid, fieldname, &var);
      if (status == MTK_SUCCESS) {
        found = 1;
        break;
      }
    }
    free(gids); 
    gids = NULL;
  }

  if (found == 0) {
    MTK_ERR_CODE_JUMP(MTK_NETCDF_READ_FAILED);
  }

  int n_attrs;
  {
    int nc_status = nc_inq_varnatts(var.gid, var.varid, &n_attrs);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_READ_FAILED);
  }
  
  attrlist_tmp = (char**)calloc(n_attrs,sizeof(char**));
  if (attrlist_tmp == NULL)
    MTK_ERR_CODE_JUMP(MTK_CALLOC_FAILED); 
  
  for (int attr_index = 0; attr_index < n_attrs; ++attr_index)
  {
    /* Get attribute information */
    char attr_name[NC_MAX_NAME+1];
    int nc_status = nc_inq_attname(var.gid, var.varid, attr_index, attr_name);
    if (nc_status != NC_NOERR) MTK_ERR_CODE_JUMP(MTK_NETCDF_READ_FAILED);

    attrlist_tmp[attr_index] = (char*)malloc((strlen(attr_name) + 1) * sizeof(char));
    if (attrlist_tmp[attr_index] == NULL)
      MTK_ERR_CODE_JUMP(MTK_MALLOC_FAILED);

    strcpy(attrlist_tmp[attr_index],attr_name);
  }
  *attrlist = attrlist_tmp;
  *num_attrs = n_attrs;
  return MTK_SUCCESS;

  
ERROR_HANDLE:
  if (gids != NULL) {
    free(gids);
  }
  if (attrlist_tmp != NULL)
    MtkStringListFree(n_attrs, &attrlist_tmp);

  if (num_attrs != NULL)
    *num_attrs = -1;

  return status_code;
}