[irods#178] Add support for adjusting the size of data objects.

Author: korydraughn

irods-vfs-impl/src/main/java/org/irods/nfsrods/vfs/IRODSVirtualFileSystem.java

@@ -1401,7 +1401,34 @@ public void setattr(Inode _inode, Stat _stat) throws IOException
 
         if (_stat.isDefined(Stat.StatAttribute.SIZE))
         {
-            log_.warn("setattr - Adjusting the size is not supported");
+            IRODSAccount acct = getCurrentIRODSUser().getAccount();
+
+            try
+            {
+                final var path = getPath(toInodeNumber(_inode));
+                log_.debug("setattr - Setting data size of [{}] to [{}] bytes.", path.toString(), _stat.getSize());
+                factory_.getDataObjectAO(acct).truncateReplica(path.toString(), _stat.getSize());
+
+                // Because iRODS timestamps are stored in seconds, operations that trigger
+                // an mtime update may not be detected by NFSRODS if the operations happen
+                // within the same second.
+                //
+                // To get around this limitation, NFSRODS must manually clear the cache
+                // so that the user sees the updates.
+                final var parentPath = path.getParent();
+                listOpCache_.remove(acct.getUserName() + "#" + parentPath.toString());
+                statObjectCache_.remove(acct.getUserName() + "_" + parentPath.toString());
+                statObjectCache_.remove(acct.getUserName() + "_" + path.toString());
+            }
+            catch (JargonException e)
+            {
+            	log_.error(e.getMessage());
+            	throw new IOException(e);
+            }
+            finally
+            {
+                closeCurrentConnection();
+            }
         }
     }
 

test/irods_tests.bats

@@ -273,3 +273,45 @@ teardown() {
     cd ..
     rmdir ${DIRECTORY}
 }
+
+@test "#178: adjust size of file" {
+    local FILENAME='truncate_test.txt'
+    local MESSAGE='hello, world!'
+
+    # Create a non-empty file.
+    echo "${MESSAGE}" > ${FILENAME}
+    run cat ${FILENAME}
+    #echo "# status = $status" >&3
+    #echo "# output = $output" >&3
+    [ "$status" -eq 0 ]
+    [ "$output" = "${MESSAGE}" ]
+
+    # Overwrite the contents of the file with a new message.
+    # The use of ">" is the real test. If the NFSRODS code is correct, the
+    # file will be truncated to zero first.
+    local NEW_MESSAGE='hello, NFSRODS!'
+    echo "${NEW_MESSAGE}" > ${FILENAME}
+    run cat ${FILENAME}
+    #echo "# status = $status" >&3
+    #echo "# output = $output" >&3
+    [ "$status" -eq 0 ]
+    [ "$output" = "${NEW_MESSAGE}" ]
+
+    # Increase the size of the file.
+    local NEW_DATA_SIZE=256
+    truncate -s${NEW_DATA_SIZE} ${FILENAME}
+    run stat -c%s ${FILENAME}
+    #echo "# status = $status" >&3
+    #echo "# output = $output" >&3
+    [ "$status" -eq 0 ]
+    [ "$output" = "${NEW_DATA_SIZE}" ]
+
+    # Show the original content is still there.
+    # Null bytes were appended during the "truncate" command
+    # and will not appear in the output.
+    run cat ${FILENAME}
+    #echo "# status = $status" >&3
+    #echo "# output = $output" >&3
+    [ "$status" -eq 0 ]
+    [ "$output" = "${NEW_MESSAGE}" ]
+}