A breakpoint is represented by a unique identifier and set of properties. A breakpoint identifier (String id) needs to be unique across all hosts and targets.
A breakpoint's property set is an extensible collection of named attributes, which define the breakpoint's location, the conditions that trigger the breakpoint, and the actions executed as a result. As such, breakpoint properties are separated into three broad categories:
The Location and Condition properties dictate how a breakpoint is installed and whether it should be triggered. The Action properties dictate the effect of the breakpoint if it is triggered.
The split of Location and Condition properties is subjective and is not meant to describe how it is implemented. Often, the Location properties dictate how a breakpoint is installed, and Condition properties dictate whether the breakpoint should be triggered. However, it is perfectly possible for an implementation to use Condition properties to control breakpoint installation and use Location properties each time the breakpoint is encountered to check if it should be triggered.
Unless stated otherwise, all Location and Condition properties have an implied "and" relationship. Conceptually, a breakpoint without any Location or Condition properties would be triggered by any state change in any of the attached contexts. Adding properties reduces the (sub)set of state changes that triggers the breakpoint.
The Location properties category contains the following properties:
Context defining properties specifying which context a breakpoint applies to are provided through the ContextIds, ContextNames or the ExecutablePaths properties.
The presence of certain properties defines what kind of breakpoint is installed.
The Type property configures whether the breakpoint should be installed as hardware or a software breakpoint.
Condition properties contain the Enabled property, the Condition and IgnoreCount properties.
Action properties contain the StopGroup and Temporary properties.
For each breakpoint a target agent maintains another extensible collection of named attributes: breakpoint status. While breakpoint properties are persistent and represent user input, breakpoint status reflects dynamic target agent reports about breakpoint current state, like actual addresses where breakpoint is installed or installation errors.
Every breakpoint is associated with a communication channel and when the channel is closed the target agent removes all corresponding breakpoints. Target agent should maintain separate breakpoint tables for each communication channel. It is allowed to set the same breakpoint (same ID) through multiple channels, target agent should treat it as single breakpoint with multiple references. Such a breakpoint is removed when all referring channels are closed.
The service uses standard format for error reports, see Error Report Format.
C • <token> • Breakpoints • set • <array of breakpoints> • <array of breakpoints> ⇒ null ⇒ [ ] ⇒ [ <breakpoints list> ] <breakpoints list> ⇒ <breakpoint data> ⇒ <breakpoints list>, <breakpoint data> <breakpoint data> ⇒ <object>
The command downloads breakpoint data to a target agent. The command is intended to be used only to initialize the target's breakpoint table when communication channel is open. After that, host should notify the target about (incremental) changes in breakpoints data by sending Add, Change and Remove commands.
Breakpoint data consists of a list of breakpoint properties. All properties are optional, except ID.
Tools and targets can define additional properties. All provided properties need to be true for a breakpoint to be installed/hit.
A breakpoint service implementation may not change the properties set by the client.
Predefined properties are:
"ID" : <string>
"Enabled" : <boolean>
"Type" : <string>
"Software"
"Hardware"
"Auto"
"ContextIds" : <string>
"ContextNames" : <string>
"ExecutablePaths" : <string>
"Location" : <string>
"AccessMode" : <int>
READ = 0x01
WRITE = 0x02
EXECUTE = 0x04
CHANGE = 0x08
"Size" : <int>
"File" : <string>
"Line" : <int>
"Column" : <int>
"MaskValue" : <int>
"Mask" : <int>
"Time" : <number>
"TimeScale" : <string>
"Relative"
"Absolute"
"TimeUnits" : <string>
"CycleCount"
"NanoSeconds"
"InstructionCount"
"Condition" : <string>
"IgnoreCount": <int>
"StopGroup" : <string>
"Temporary" : <boolean>
Reply:
R • <token> • <error report> •
Examples:
The following properties install a hardware breakpoint at address 0x1000
for all attached contexts:
ID = "1"
Type = "Hardware"
Location = "0x1000"
The following additional property limits the number of contexts for which the breakpoint by providing the ContextIDs property:
ContextIds = ["core0", "core1"]
The following additional property stops the specified contexts when breakpoint 1 is hit:
StopGroup = ["core3", "core5"]
The following properties set a watchpoint that stops core0
when variable fooVar
is read from or written to by Core5
:
ID = "2"
Type = "Hardware"
Location = "fooVar"
Size = 4
AccessMode = 0x01 | 0x02
ContextIDs = ["core5"]
StopGroup = ["core0"]
The following additional properties further restrict the watchpoint to trigger only if an odd value is read from or written to the location.
MaskValue = 0x00000001
Mask = 0x00000001
The following properties set a temporal breakpoint that stops core0
at the specified absolute time.
ID = "3"
ContextIDs = ["core0"]
Time = 245
TimeUnits = "NanoSeconds"
TimeScale = "Absolute"
C • <token> • Breakpoints • add • <breakpoint data> •
The command adds a breakpoint to the target agent breakpoint table. The host should send this command when the user creates a new breakpoint
Reply:
R • <token> • <error report> •
C • <token> • Breakpoints • change • <breakpoint data> •
The command updates the breakpoint data in the target agent breakpoint table. The host should send this command when the user modifies a breakpoint
Reply:
R • <token> • <error report> •
C • <token> • Breakpoints • enable • <array of breakpoint IDs> • <array of breakpoint IDs> ⇒ null ⇒ [ ] ⇒ [ <breakpoint IDs list> ] <breakpoint IDs list> ⇒ <breakpoint ID> ⇒ <breakpoint IDs list>, <breakpoint ID> <breakpoint ID> ⇒ <string>
The command enables a list of breakpoints - sets breakpoint property "Enabled" to true.
Reply:
R • <token> • <error report> •
C • <token> • Breakpoints • disable • <array of breakpoint IDs> •
The command disables a list of breakpoints - sets breakpoint property "Enabled" to false.
Reply:
R • <token> • <error report> •
C • <token> • Breakpoints • remove • <array of breakpoint IDs> •
The command removes a list of breakpoints. Host should send this command when user deletes breakpoints.
Reply:
R • <token> • <error report> •
C • <token> • Breakpoints • getIDs •
The command uploads IDs of breakpoints known to target agent, including breakpoints that are set through different communication channels. It is up to the client to keep track of which breakpoints it has set such that it can know which breakpoint are set by other channels.
Reply:
R • <token> • <error report> • <array of breakpoint IDs> •
C • <token> • Breakpoints • getProperties • <string: breakpoint ID> •
The command uploads the properties of the given breakpoint from the target agent breakpoint table.
Reply:
R • <token> • <error report> • <breakpoint data> •
C • <token> • Breakpoints • getStatus • <string: breakpoint ID> •
The command uploads the status of given the breakpoint from the target agent.
Reply:
R • <token> • <error report> • <breakpoint status> • <breakpoint status> ⇒ <object>
Breakpoint status consists of a list of status properties. All properties are optional. Tools and targets can define additional properties. Setting any properties that are not supported by or unknown to the service implementation will yield an error, which is reported in the Error property of the breakpoint status object.
Predefined properties are:
"Instances" : <array of instance status data>
"Error" : <string>
"File" : <string>
"Line" : <int>
"Column" : <int>
<array of instance status data> ⇒ null ⇒ [ ] ⇒ [ <Instance status data list> ] <Instance status data list> ⇒ <Instance status data> ⇒ <Instance staus data list>, <Instance status data> <Instance status data> ⇒ <object>
Instance status data consists of a list of properties pertaining to each installed instance of the breakpoint.
Predefined properties are:
"Error" : <string>
"BreakpointType" : <string>
"LocationContext" : <string>
"Address" : <string>
C • <token> • Breakpoints • getCapabilities • <string: context ID> •
The command reports breakpoint service capabilities to clients so they can adjust to different implementations of the service. When called with a null ("") context ID the global capabilities are returned, otherwise context specific capabilities are returned. A special capability property is used to indicate that all child contexts have the same capabilities.
Reply:
R • <token> • <error report> • <service capabilities> • <service capabilities> ⇒ <object>
Service capabilities consist of a list of properties. All properties are optional. Tools and targets can define additional properties. Predefined properties are:
"ID" : <string: context ID>
- ID of a context that was used to query capabilities
"HasChildren" : <boolean>
- if true, children of the context can have different capabilities
"Address" : <boolean>
- if true, "Address" breakpoint property is supported
"Condition" : <boolean>
- if true, "Condition" breakpoint property is supported
"FileLine" : <boolean>
- if true, "File", "Line" and "Column" breakpoint properties are supported
Breakpoints service events are sent to notify clients about breakpoint properties and status changes. Note that contextAdded, contextChanged and contextRemoved events carry exactly same set of breakpoint properties that was sent by a client to a target. The purpose of these events is to let all clients know about breakpoints that were created by other clients.
E • Breakpoints • status • <string: breakpoint ID> • <breakpoint status> • E • Breakpoints • contextAdded • <array of breakpoints> • E • Breakpoints • contextChanged • <array of breakpoints> • E • Breakpoints • contextRemoved • <array of breakpoint IDs> •
/** * Breakpoint is represented by unique identifier and set of properties. * Breakpoint identifier (String id) needs to be unique across all hosts and targets. * * Breakpoint properties (Map<String,Object>) is extensible collection of named attributes, * which define breakpoint location and behavior. This module defines some common * attribute names (see PROP_*), host tools and target agents may support additional attributes. * * For each breakpoint a target agent maintains another extensible collection of named attributes: * breakpoint status (Map<String,Object>, see STATUS_*). While breakpoint properties are * persistent and represent user input, breakpoint status reflects dynamic target agent reports * about breakpoint current state, like actual addresses where breakpoint is installed or installation errors. */ public interface IBreakpoints extends IService { /** * Service name. */ static final String NAME = "Breakpoints"; /** * Breakpoint property names. */ static final String PROP_ID = "ID", // String PROP_ENABLED = "Enabled", // Boolean PROP_TYPE = "BreakpointType", // String PROP_CONTEXTNAMES = "ContextNames", // Array PROP_CONTEXTIDS = "ContextIds", // Array PROP_EXECUTABLEPATHS = "ExecPaths", // Array PROP_LOCATION = "Location", // String PROP_SIZE = "Size", // Number PROP_ACCESSMODE = "AccessMode", // Number PROP_FILE = "File", // String PROP_LINE = "Line", // Number PROP_COLUMN = "Column", // Number PROP_PATTERN = "MaskValue", // Number PROP_MASK = "Mask", // Number PROP_STOP_GROUP = "StopGroup", // Array PROP_IGNORECOUNT = "IgnoreCount", // Number PROP_TIME = "Time", // Number PROP_SCALE = "TimeScale", // String PROP_UNITS = "TimeUnits", // String PROP_CONDITION = "Condition", // String PROP_TEMPORARY = "Temporary"; // Boolean /** * BreakpointType values */ static final String TYPE_RELATIVE = "Software", TYPE_ABSOLUTE = "Hardware", TYPE_AUTO = "Auto"; /** * AccessMode values */ static final int ACCESSMODE_READ = 0x01, ACCESSMODE_WRITE = 0x02, ACCESSMODE_EXECUTE = 0x04, ACCESSMODE_CHANGE = 0x08; /** * TimeScale values */ static final String TIMESCALE_RELATIVE = "Relative", TIMESCALE_ABSOLUTE = "Absolute"; /** * TimeUnits values */ static final String TIMEUNIT_NSECS = "Nanoseconds", TIMEUNIT_CYCLE_COUNT = "CycleCount", TIMEUNIT_INSTRUCTION_COUNT = "InstructionCount"; /** * Breakpoint status field names. */ static final String STATUS_INSTALLED = "Installed", // Array of addresses STATUS_ERROR = "Error", // String STATUS_FILE = "File", // String STATUS_LINE = "Line", // Number STATUS_COLUMN = "Column"; // Number /** * Breakpoint service capabilities. */ static final String CAPABILITY_CONTEXT_ID = "ID", // String CAPABILITY_HAS_CHILDREN = "HasChildren", // Boolean CAPABILITY_ADDRESS = "Address", // Boolean CAPABILITY_CONDITION = "Condition", // Boolean CAPABILITY_FILE_LINE = "FileLine"; // Boolean /** * Call back interface for breakpoint service commands. */ interface DoneCommand { void doneCommand(IToken token, Exception error); } /** * Download breakpoints data to target agent. * The command is intended to be used only to initialize target breakpoints table * when communication channel is open. After that, host should * notify target about (incremental) changes in breakpoint data by sending * add, change and remove commands. * * @param properties - array of breakpoints. * @param done - command result call back object. */ IToken set(Map<String,Object>[] properties, DoneCommand done); /** * Called when breakpoint is added into breakpoints table. * @param properties - breakpoint properties. * @param done - command result call back object. */ IToken add(Map<String,Object> properties, DoneCommand done); /** * Called when breakpoint properties are changed. * @param properties - breakpoint properties. * @param done - command result call back object. */ IToken change(Map<String,Object> properties, DoneCommand done); /** * Tell target to change (only) PROP_ENABLED breakpoint property 'true'. * @param ids - array of enabled breakpoint identifiers. * @param done - command result call back object. */ IToken enable(String[] ids, DoneCommand done); /** * Tell target to change (only) PROP_ENABLED breakpoint property to 'false'. * @param ids - array of disabled breakpoint identifiers. * @param done - command result call back object. */ IToken disable(String[] ids, DoneCommand done); /** * Tell target to remove breakpoint. * @param id - unique breakpoint identifier. * @param done - command result call back object. */ IToken remove(String[] ids, DoneCommand done); /** * Upload IDs of breakpoints known to target agent. * @param done - command result call back object. */ IToken getIDs(DoneGetIDs done); interface DoneGetIDs { void doneGetIDs(IToken token, Exception error, String[] ids); } /** * Upload properties of given breakpoint from target agent breakpoint table. * @param id - unique breakpoint identifier. * @param done - command result call back object. */ IToken getProperties(String id, DoneGetProperties done); interface DoneGetProperties { void doneGetProperties(IToken token, Exception error, Map<String,Object> properties); } /** * Upload status of given breakpoint from target agent. * @param id - unique breakpoint identifier. * @param done - command result call back object. */ IToken getStatus(String id, DoneGetStatus done); interface DoneGetStatus { void doneGetStatus(IToken token, Exception error, Map<String,Object> status); } /** * Report breakpoint service capabilities to clients so they * can adjust to different implementations of the service. * When called with a null ("") context ID the global capabilities are returned, * otherwise context specific capabilities are returned. A special capability * property is used to indicate that all child contexts have the same * capabilities. * @param id - a context ID or null. * @param done - command result call back object. */ IToken getCapabilities(String id, DoneGetCapabilities done); interface DoneGetCapabilities { void doneGetCapabilities(IToken token, Exception error, Map<String,Object> capabilities); } /** * Breakpoints service events listener. * Note that contextAdded, contextChanged and contextRemoved events carry exactly same set * of breakpoint properties that was sent by a client to a target. The purpose of these events is to * let all clients know about breakpoints that were created by other clients. */ interface BreakpointsListener { /** * Called when breakpoint status changes. * @param id - unique breakpoint identifier. * @param status - breakpoint status. */ void breakpointStatusChanged(String id, Map<String,Object> status); /** * Called when a new breakpoints are added. * @param bps - array of breakpoints. */ void contextAdded(Map<String,Object>[] bps); /** * Called when breakpoint properties change. * @param bps - array of breakpoints. */ void contextChanged(Map<String,Object>[] bps); /** * Called when breakpoints are removed. * @param ids - array of breakpoint IDs. */ void contextRemoved(String[] ids); } /** * Add breakpoints service event listener. * @param listener - object that implements BreakpointsListener interface. */ void addListener(BreakpointsListener listener); /** * Remove breakpoints service event listener. * @param listener - object that implements BreakpointsListener interface. */ void removeListener(BreakpointsListener listener); }