Merge pull request #1317 from Unidata/fillhack.dmh

Add hack to deal with DAP2 signed byte conversion.

libdap2/ncd2dispatch.c

@@ -780,11 +780,45 @@ fprintf(stderr,"\n");
  }
  var->ncid = varid;
  if(var->attributes != NULL) {
+ NCattribute* unsignedatt = NULL;
+ int unsignedval = 0;
+ /* See if variable has _Unsigned attribute */ 
  for(j=0;j<nclistlength(var->attributes);j++) {
  NCattribute* att = (NCattribute*)nclistget(var->attributes,j);
+ if(strcmp(att->name,"_Unsigned") == 0) {
+ char* value = nclistget(att->values,0);
+ unsignedatt = att;
+ if(value != NULL) {
+ if(strcasecmp(value,"false")==0
+ || strcmp(value,"0")==0)
+ unsignedval = 0;
+ else
+ unsignedval = 1;
+ }
+ break;
+ }
+ }
+ for(j=0;j<nclistlength(var->attributes);j++) {
+ NCattribute* att = (NCattribute*)nclistget(var->attributes,j);
+ char* val = NULL;
  /* Check for _FillValue/Variable mismatch */
  if(strcmp(att->name,"_FillValue")==0) {
- if(att->etype != var->etype) {
+ /* Special case var is byte, fillvalue is int16 and 
+ unsignedattr == 0;
+ This exception is needed because DAP2 byte type
+ is equivalent to netcdf ubyte type. So passing
+ a signed byte thru DAP2 requires some type and
+ signedness hacking that we have to undo.
+ */
+ if(var->etype == NC_UBYTE
+ && att->etype == NC_SHORT
+ && unsignedatt != NULL && unsignedval == 0) {
+ /* Forcibly change the attribute type and signedness */
+ att->etype = NC_BYTE;
+ val = nclistremove(unsignedatt->values,0);
+ if(val) free(val);
+ nclistpush(unsignedatt->values,strdup("false"));
+ } else if(att->etype != var->etype) {/* other mismatches */
  /* Log a message */
  nclog(NCLOGERR,"_FillValue/Variable type mismatch: variable=%s",var->ncbasename);
  /* See if mismatch is allowed */

oc2/ochttp.c

@@ -138,6 +138,7 @@ ocfetchurl(CURL* curl, const char* url, NCbytes* buf, long* filetime)
 fail:
  nclog(NCLOGERR, "curl error: %s", curl_easy_strerror(cstat));
  switch (httpcode) {
+ case 400: stat = OC_EBADURL; break;
  case 401: stat = OC_EAUTH; break;
  case 404: stat = OC_ENOFILE; break;
  case 500: stat = OC_EDAPSVC; break;