Changing the dataitem ID in Device.XML while the agent is running will sometimes cause a crash. To simulate changing the ID of the dataitem in dummyAdapter_42 I used the following python script
import xml.etree.ElementTree as ET
import time
device_xml = 'C:/PROGRAMS/cppagent-2.2/bin/Devices.xml'
id_counter = 0
def write_device_xml_updates():
global counter
global id_counter
tree:ET.ElementTree = ET.ElementTree()
root:ET.Element = ET.Element("")
with open(device_xml, "rb") as f:
tree = ET.parse(f)
root = tree.getroot()
device = root.findall('*/Device')[0]
items = device.findall(".//*[@id]")
for item in items:
item.attrib["id"] = f"newEleID{id_counter}"
id_counter += 1
with open(device_xml, "wb") as f:
tree.write(f)
while True:
write_device_xml_updates()
time.sleep(25)Here is the Devices.XML I used:
<MTConnectDevices>
<Devices>
<Device uuid="dummyAdapter_42" id="dummyAdapter_42" name="dummyAdapter">
<Components>
<Controller id="dummyCtl">
<DataItems>
<DataItem id="msgTest" type="MESSAGE" category= "EVENT"></DataItem>
</DataItems>
</Controller>
</Components>
</Device>
</Devices>
</MTConnectDevices>
Here is my agent.cfg:
Devices = Devices.xml
AllowPut = true
ReconnectInterval = 1000
BufferSize = 17
SchemaVersion = 2.0
MonitorConfigFiles = true
Adapters {
dummyAdapter {
Host = 127.0.0.1
Port = 7790
}
}
Files {
schemas {
Path = ../schemas
Location = /schemas/
}
styles {
Path = ../styles
Location = /styles/
}
Favicon {
Path = ../styles/favicon.ico
Location = /favicon.ico
}
}
# StreamsStyle { Location = /styles/Streams.xsl }
DevicesStyle { Location = /styles/styles.xsl }
StreamsStyle { Location = /styles/styles.xsl }
# Logger Configuration
logger_config
{
logging_level = debug
}
Every 25 seconds the python script will update the Devices.XML and let the agent attempt to update the device model.
The crash occurs in the function void Observation::updateDataItem(std::unordered_map<std::string, WeakDataItemPtr> &diMap) due to m_dataItem.lock() returning an empty shared pointer (DataItemPtr).
Inside CircularBuffer::updateDataItems() when iterating over m_slidingBuffer, if the current Observation is an orphan, inside of o->updateDataItem(diMap); will crash when attempting to use the result of m_dataItem.lock(); as a parameter to diMap.find()
Changing the dataitem ID in Device.XML while the agent is running will sometimes cause a crash. To simulate changing the ID of the dataitem in
dummyAdapter_42I used the following python scriptHere is the Devices.XML I used:
Here is my agent.cfg:
Every 25 seconds the python script will update the Devices.XML and let the agent attempt to update the device model.
The crash occurs in the function
void Observation::updateDataItem(std::unordered_map<std::string, WeakDataItemPtr> &diMap)due tom_dataItem.lock()returning an empty shared pointer (DataItemPtr).Inside
CircularBuffer::updateDataItems()when iterating overm_slidingBuffer, if the current Observation is an orphan, inside ofo->updateDataItem(diMap);will crash when attempting to use the result ofm_dataItem.lock();as a parameter todiMap.find()