Add code to test netCDF attribute handling.

* This exercises the code for which a bug was introduced in r3181 and
  fixed in r3200.

tests/test_cdf_read.c

@@ -8,6 +8,9 @@
 
 #include "cdi.h"
 
+static void
+printAtts(int vlistID);
+
 int main(int argc, const char **argv)
 {
   const char *fname = "test.nc";
@@ -30,11 +33,13 @@ int main(int argc, const char **argv)
   size_t bufSize = 0;
   size_t allNmissSum = 0;
 
+  printAtts(vlistID);
+
   for (int tsID = 0; streamInqTimestep(streamID, tsID); ++tsID)
     {
       for (size_t varID = 0; varID < nVars; ++varID)
         {
-          size_t memSize = (size_t)vlistInqVarSize(vlistID, varID)
+          size_t memSize = (size_t)vlistInqVarSize(vlistID, (int)varID)
             * sizeof (double);
           int nmiss;
           if (memSize > bufSize)
@@ -58,6 +63,111 @@ int main(int argc, const char **argv)
   return EXIT_SUCCESS;
 }
 
+static void
+printAtts(int vlistID)
+{
+  size_t nVars = (size_t)vlistNvars(vlistID);
+  static const char globDesc[] = "global",
+    varDescPrefix[] = "variable ";
+  size_t digitsPerInt = 9;
+  size_t bufSize = digitsPerInt + sizeof (varDescPrefix);
+  void *restrict buf = malloc(bufSize);
+  if (!buf)
+    {
+      perror("attribute buffer resize failed");
+      exit(EXIT_FAILURE);
+    }
+  for (size_t varIdx = 0; varIdx <= nVars; ++varIdx)
+    {
+      int nAtts, attType, attLen;
+      char attName[CDI_MAX_NAME + 1];
+      int varID = (int)varIdx - 1;
+      vlistInqNatts(vlistID, varID, &nAtts);
+      for (size_t attIdx = 0; attIdx < (size_t)nAtts; attIdx++ )
+        {
+          int rc = vlistInqAtt(vlistID, varID, (int)attIdx,
+                               attName, &attType, &attLen);
+          {
+            const char *varDesc = varIdx > 0
+              ? (sprintf(buf, "%s%d", varDescPrefix,
+                         vlistInqVarCode(vlistID, varID)), buf)
+              : globDesc;
+            printf("%s attribute \"%s\", value: ",
+                   varDesc, attName);
+          }
+          if (attLen < 0)
+            goto attGetFail;
+          size_t elemSize = 0;
+          switch (attType)
+            {
+            case DATATYPE_TXT:
+              elemSize = 1;
+              break;
+            case DATATYPE_FLT:
+              elemSize = sizeof (double);
+              break;
+            case DATATYPE_INT:
+              elemSize = sizeof (int);
+              break;
+            }
+
+          size_t attSize = elemSize * ((size_t)attLen + 1);
+          if (attSize > bufSize)
+            {
+              if (!(buf = realloc(buf, attSize)))
+                {
+                  perror("attribute buffer resize failed");
+                  exit(EXIT_FAILURE);
+                }
+            }
+
+          switch (attType)
+            {
+            case DATATYPE_TXT:
+              rc = vlistInqAttTxt(vlistID, (int)varID, attName,
+                                  attLen, buf);
+              if (rc == CDI_NOERR)
+                printf("\"%.*s\"", attLen, (char *)buf);
+              break;
+            case DATATYPE_FLT:
+              rc = vlistInqAttFlt(vlistID, (int)varID, attName,
+                                  attLen + 1, buf);
+              if (rc == CDI_NOERR && attLen)
+                {
+                  const double *restrict dp = buf;
+                  printf("%10g", dp[0]);
+                  for (size_t i = 1; i < (size_t)attLen; ++i)
+                    printf(", %10g", dp[i]);
+                }
+              break;
+            case DATATYPE_INT:
+              rc = vlistInqAttInt(vlistID, (int)varID, attName,
+                                  attLen + 1, buf);
+              if (rc == CDI_NOERR && attLen)
+                {
+                  const int *restrict ip = buf;
+                  printf("%d", ip[0]);
+                  for (size_t i = 1; i < (size_t)attLen; ++i)
+                    printf(", %d", ip[i]);
+                }
+              break;
+            }
+
+          if (rc == CDI_NOERR)
+            {
+              putchar('\n');
+            }
+          else
+            {
+              attGetFail:
+              puts("error retrieving value");
+            }
+        }
+    }
+  free(buf);
+}
+
+
 /*
  * Local Variables:
  * c-file-style: "Java"

tests/test_cdf_transformation.in

@@ -18,6 +18,11 @@ if [ "$missValueCount" -ne 1 ]; then
   echo "Mismatch in expected number of missing values!" >&2
   exit 1
 fi
+if ! echo "$digest" | grep 'variable 1 attribute "CDI Text Attribute test, created by", value: "CDI test_cdf_write"' >/dev/null; then
+  echo "Expected attribute not found" >&2
+  exit 1
+fi
+
 #
 # Local Variables:
 # mode: sh

tests/test_cdf_write.c

@@ -27,7 +27,7 @@ int main(int argc, const char **argv)
 {
   /* todo: handle optional arguments here to increase test coverage */
   const char *fname = "test.nc";
-  if (argc)
+  if (argc > 1)
     fname = argv[1];
   int streamID = streamOpenWrite(fname, FILETYPE_NC);
 
@@ -73,6 +73,11 @@ int main(int argc, const char **argv)
   int vlistID = vlistCreate();
   int varID = vlistDefVar(vlistID, gridID, zaxisID, TSTEP_INSTANT);
   vlistDefVarMissval(vlistID, varID, missValue);
+  {
+    static const char creatorText[] = "CDI test_cdf_write";
+    vlistDefAttTxt(vlistID, varID, "CDI Text Attribute test, created by",
+                   sizeof (creatorText) - 1, creatorText);
+  }
 
   int taxisID = taxisCreate(TAXIS_ABSOLUTE);
   vlistDefTaxis(vlistID, taxisID);