delve/service/rpc2/client.go
Alessandro Arzilli 8bb93e9ae1
proc/gdbserial,debugger: allow clients to stop a recording (#1890)
Allows Delve clients to stop a recording midway by sending a
Command('halt')
request.

This is implemented by changing debugger.New to start recording the
process on a separate goroutine while holding the processMutex locked.
By locking the processMutex we ensure that almost all RPC requests will
block until the recording is done, since we can not respond correctly
to any of them.
API calls that do not require manipulating or examining the target
process, such as "IsMulticlient", "SetApiVersion" and
"GetState(nowait=true)" will work while we are recording the process.

Two other internal changes are made to the API: both GetState and
Restart become asynchronous requests, like Command. Restart because
this way it can be interrupted by a StopRecording request if the
rerecord option is passed.
GetState because clients need a call that will block until the
recording is compelted and can also be interrupted with a
StopRecording.

Clients that are uninterested in allowing the user to stop a recording
can ignore this change, since eventually they will make a request to
Delve that will block until the recording is completed.

Clients that wish to support this feature must:

1. call GetState(nowait=false) after connecting to Delve, before any
   call that would need to manipulate the target process
2. allow the user to send a StopRecording request during the initial
   GetState call
3. allow the user to send a StopRecording request during any subsequent
   Restart(rerecord=true) request (if supported).

Implements #1747
2020-03-24 09:09:28 -07:00

466 lines
14 KiB
Go

package rpc2
import (
"fmt"
"log"
"net"
"net/rpc"
"net/rpc/jsonrpc"
"time"
"github.com/go-delve/delve/service"
"github.com/go-delve/delve/service/api"
)
// Client is a RPC service.Client.
type RPCClient struct {
client *rpc.Client
retValLoadCfg *api.LoadConfig
}
// Ensure the implementation satisfies the interface.
var _ service.Client = &RPCClient{}
// NewClient creates a new RPCClient.
func NewClient(addr string) *RPCClient {
client, err := jsonrpc.Dial("tcp", addr)
if err != nil {
log.Fatal("dialing:", err)
}
return newFromRPCClient(client)
}
func newFromRPCClient(client *rpc.Client) *RPCClient {
c := &RPCClient{client: client}
c.call("SetApiVersion", api.SetAPIVersionIn{APIVersion: 2}, &api.SetAPIVersionOut{})
return c
}
// NewClientFromConn creates a new RPCClient from the given connection.
func NewClientFromConn(conn net.Conn) *RPCClient {
return newFromRPCClient(jsonrpc.NewClient(conn))
}
func (c *RPCClient) ProcessPid() int {
out := new(ProcessPidOut)
c.call("ProcessPid", ProcessPidIn{}, out)
return out.Pid
}
func (c *RPCClient) LastModified() time.Time {
out := new(LastModifiedOut)
c.call("LastModified", LastModifiedIn{}, out)
return out.Time
}
func (c *RPCClient) Detach(kill bool) error {
defer c.client.Close()
out := new(DetachOut)
return c.call("Detach", DetachIn{kill}, out)
}
func (c *RPCClient) Restart() ([]api.DiscardedBreakpoint, error) {
out := new(RestartOut)
err := c.call("Restart", RestartIn{"", false, nil, false}, out)
return out.DiscardedBreakpoints, err
}
func (c *RPCClient) RestartFrom(rerecord bool, pos string, resetArgs bool, newArgs []string) ([]api.DiscardedBreakpoint, error) {
out := new(RestartOut)
err := c.call("Restart", RestartIn{pos, resetArgs, newArgs, rerecord}, out)
return out.DiscardedBreakpoints, err
}
func (c *RPCClient) GetState() (*api.DebuggerState, error) {
var out StateOut
err := c.call("State", StateIn{NonBlocking: false}, &out)
return out.State, err
}
func (c *RPCClient) GetStateNonBlocking() (*api.DebuggerState, error) {
var out StateOut
err := c.call("State", StateIn{NonBlocking: true}, &out)
return out.State, err
}
func (c *RPCClient) Continue() <-chan *api.DebuggerState {
return c.continueDir(api.Continue)
}
func (c *RPCClient) Rewind() <-chan *api.DebuggerState {
return c.continueDir(api.Rewind)
}
func (c *RPCClient) DirectionCongruentContinue() <-chan *api.DebuggerState {
return c.continueDir(api.DirectionCongruentContinue)
}
func (c *RPCClient) continueDir(cmd string) <-chan *api.DebuggerState {
ch := make(chan *api.DebuggerState)
go func() {
for {
out := new(CommandOut)
err := c.call("Command", &api.DebuggerCommand{Name: cmd, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
state := out.State
if err != nil {
state.Err = err
}
if state.Exited {
// Error types apparently cannot be marshalled by Go correctly. Must reset error here.
state.Err = fmt.Errorf("Process %d has exited with status %d", c.ProcessPid(), state.ExitStatus)
}
ch <- &state
if err != nil || state.Exited {
close(ch)
return
}
isbreakpoint := false
istracepoint := true
for i := range state.Threads {
if state.Threads[i].Breakpoint != nil {
isbreakpoint = true
istracepoint = istracepoint && (state.Threads[i].Breakpoint.Tracepoint || state.Threads[i].Breakpoint.TraceReturn)
}
}
if !isbreakpoint || !istracepoint {
close(ch)
return
}
}
}()
return ch
}
func (c *RPCClient) Next() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.Next, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) ReverseNext() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.ReverseNext, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) Step() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.Step, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) ReverseStep() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.ReverseStep, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) StepOut() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.StepOut, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) ReverseStepOut() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.ReverseStepOut, ReturnInfoLoadConfig: c.retValLoadCfg}, &out)
return &out.State, err
}
func (c *RPCClient) Call(goroutineID int, expr string, unsafe bool) (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.Call, ReturnInfoLoadConfig: c.retValLoadCfg, Expr: expr, UnsafeCall: unsafe, GoroutineID: goroutineID}, &out)
return &out.State, err
}
func (c *RPCClient) StepInstruction() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.StepInstruction}, &out)
return &out.State, err
}
func (c *RPCClient) ReverseStepInstruction() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.ReverseStepInstruction}, &out)
return &out.State, err
}
func (c *RPCClient) SwitchThread(threadID int) (*api.DebuggerState, error) {
var out CommandOut
cmd := api.DebuggerCommand{
Name: api.SwitchThread,
ThreadID: threadID,
}
err := c.call("Command", cmd, &out)
return &out.State, err
}
func (c *RPCClient) SwitchGoroutine(goroutineID int) (*api.DebuggerState, error) {
var out CommandOut
cmd := api.DebuggerCommand{
Name: api.SwitchGoroutine,
GoroutineID: goroutineID,
}
err := c.call("Command", cmd, &out)
return &out.State, err
}
func (c *RPCClient) Halt() (*api.DebuggerState, error) {
var out CommandOut
err := c.call("Command", api.DebuggerCommand{Name: api.Halt}, &out)
return &out.State, err
}
func (c *RPCClient) GetBreakpoint(id int) (*api.Breakpoint, error) {
var out GetBreakpointOut
err := c.call("GetBreakpoint", GetBreakpointIn{id, ""}, &out)
return &out.Breakpoint, err
}
func (c *RPCClient) GetBreakpointByName(name string) (*api.Breakpoint, error) {
var out GetBreakpointOut
err := c.call("GetBreakpoint", GetBreakpointIn{0, name}, &out)
return &out.Breakpoint, err
}
func (c *RPCClient) CreateBreakpoint(breakPoint *api.Breakpoint) (*api.Breakpoint, error) {
var out CreateBreakpointOut
err := c.call("CreateBreakpoint", CreateBreakpointIn{*breakPoint}, &out)
return &out.Breakpoint, err
}
func (c *RPCClient) ListBreakpoints() ([]*api.Breakpoint, error) {
var out ListBreakpointsOut
err := c.call("ListBreakpoints", ListBreakpointsIn{}, &out)
return out.Breakpoints, err
}
func (c *RPCClient) ClearBreakpoint(id int) (*api.Breakpoint, error) {
var out ClearBreakpointOut
err := c.call("ClearBreakpoint", ClearBreakpointIn{id, ""}, &out)
return out.Breakpoint, err
}
func (c *RPCClient) ClearBreakpointByName(name string) (*api.Breakpoint, error) {
var out ClearBreakpointOut
err := c.call("ClearBreakpoint", ClearBreakpointIn{0, name}, &out)
return out.Breakpoint, err
}
func (c *RPCClient) AmendBreakpoint(bp *api.Breakpoint) error {
out := new(AmendBreakpointOut)
err := c.call("AmendBreakpoint", AmendBreakpointIn{*bp}, out)
return err
}
func (c *RPCClient) CancelNext() error {
var out CancelNextOut
return c.call("CancelNext", CancelNextIn{}, &out)
}
func (c *RPCClient) ListThreads() ([]*api.Thread, error) {
var out ListThreadsOut
err := c.call("ListThreads", ListThreadsIn{}, &out)
return out.Threads, err
}
func (c *RPCClient) GetThread(id int) (*api.Thread, error) {
var out GetThreadOut
err := c.call("GetThread", GetThreadIn{id}, &out)
return out.Thread, err
}
func (c *RPCClient) EvalVariable(scope api.EvalScope, expr string, cfg api.LoadConfig) (*api.Variable, error) {
var out EvalOut
err := c.call("Eval", EvalIn{scope, expr, &cfg}, &out)
return out.Variable, err
}
func (c *RPCClient) SetVariable(scope api.EvalScope, symbol, value string) error {
out := new(SetOut)
return c.call("Set", SetIn{scope, symbol, value}, out)
}
func (c *RPCClient) ListSources(filter string) ([]string, error) {
sources := new(ListSourcesOut)
err := c.call("ListSources", ListSourcesIn{filter}, sources)
return sources.Sources, err
}
func (c *RPCClient) ListFunctions(filter string) ([]string, error) {
funcs := new(ListFunctionsOut)
err := c.call("ListFunctions", ListFunctionsIn{filter}, funcs)
return funcs.Funcs, err
}
func (c *RPCClient) ListTypes(filter string) ([]string, error) {
types := new(ListTypesOut)
err := c.call("ListTypes", ListTypesIn{filter}, types)
return types.Types, err
}
func (c *RPCClient) ListPackageVariables(filter string, cfg api.LoadConfig) ([]api.Variable, error) {
var out ListPackageVarsOut
err := c.call("ListPackageVars", ListPackageVarsIn{filter, cfg}, &out)
return out.Variables, err
}
func (c *RPCClient) ListLocalVariables(scope api.EvalScope, cfg api.LoadConfig) ([]api.Variable, error) {
var out ListLocalVarsOut
err := c.call("ListLocalVars", ListLocalVarsIn{scope, cfg}, &out)
return out.Variables, err
}
func (c *RPCClient) ListThreadRegisters(threadID int, includeFp bool) (api.Registers, error) {
out := new(ListRegistersOut)
err := c.call("ListRegisters", ListRegistersIn{ThreadID: threadID, IncludeFp: includeFp, Scope: nil}, out)
return out.Regs, err
}
func (c *RPCClient) ListScopeRegisters(scope api.EvalScope, includeFp bool) (api.Registers, error) {
out := new(ListRegistersOut)
err := c.call("ListRegisters", ListRegistersIn{ThreadID: 0, IncludeFp: includeFp, Scope: &scope}, out)
return out.Regs, err
}
func (c *RPCClient) ListFunctionArgs(scope api.EvalScope, cfg api.LoadConfig) ([]api.Variable, error) {
var out ListFunctionArgsOut
err := c.call("ListFunctionArgs", ListFunctionArgsIn{scope, cfg}, &out)
return out.Args, err
}
func (c *RPCClient) ListGoroutines(start, count int) ([]*api.Goroutine, int, error) {
var out ListGoroutinesOut
err := c.call("ListGoroutines", ListGoroutinesIn{start, count}, &out)
return out.Goroutines, out.Nextg, err
}
func (c *RPCClient) Stacktrace(goroutineId, depth int, opts api.StacktraceOptions, cfg *api.LoadConfig) ([]api.Stackframe, error) {
var out StacktraceOut
err := c.call("Stacktrace", StacktraceIn{goroutineId, depth, false, false, opts, cfg}, &out)
return out.Locations, err
}
func (c *RPCClient) Ancestors(goroutineID int, numAncestors int, depth int) ([]api.Ancestor, error) {
var out AncestorsOut
err := c.call("Ancestors", AncestorsIn{goroutineID, numAncestors, depth}, &out)
return out.Ancestors, err
}
func (c *RPCClient) AttachedToExistingProcess() bool {
out := new(AttachedToExistingProcessOut)
c.call("AttachedToExistingProcess", AttachedToExistingProcessIn{}, out)
return out.Answer
}
func (c *RPCClient) FindLocation(scope api.EvalScope, loc string, findInstructions bool) ([]api.Location, error) {
var out FindLocationOut
err := c.call("FindLocation", FindLocationIn{scope, loc, !findInstructions}, &out)
return out.Locations, err
}
// Disassemble code between startPC and endPC
func (c *RPCClient) DisassembleRange(scope api.EvalScope, startPC, endPC uint64, flavour api.AssemblyFlavour) (api.AsmInstructions, error) {
var out DisassembleOut
err := c.call("Disassemble", DisassembleIn{scope, startPC, endPC, flavour}, &out)
return out.Disassemble, err
}
// Disassemble function containing pc
func (c *RPCClient) DisassemblePC(scope api.EvalScope, pc uint64, flavour api.AssemblyFlavour) (api.AsmInstructions, error) {
var out DisassembleOut
err := c.call("Disassemble", DisassembleIn{scope, pc, 0, flavour}, &out)
return out.Disassemble, err
}
// Recorded returns true if the debugger target is a recording.
func (c *RPCClient) Recorded() bool {
out := new(RecordedOut)
c.call("Recorded", RecordedIn{}, out)
return out.Recorded
}
// TraceDirectory returns the path to the trace directory for a recording.
func (c *RPCClient) TraceDirectory() (string, error) {
var out RecordedOut
err := c.call("Recorded", RecordedIn{}, &out)
return out.TraceDirectory, err
}
// Checkpoint sets a checkpoint at the current position.
func (c *RPCClient) Checkpoint(where string) (checkpointID int, err error) {
var out CheckpointOut
err = c.call("Checkpoint", CheckpointIn{where}, &out)
return out.ID, err
}
// ListCheckpoints gets all checkpoints.
func (c *RPCClient) ListCheckpoints() ([]api.Checkpoint, error) {
var out ListCheckpointsOut
err := c.call("ListCheckpoints", ListCheckpointsIn{}, &out)
return out.Checkpoints, err
}
// ClearCheckpoint removes a checkpoint
func (c *RPCClient) ClearCheckpoint(id int) error {
var out ClearCheckpointOut
err := c.call("ClearCheckpoint", ClearCheckpointIn{id}, &out)
return err
}
func (c *RPCClient) SetReturnValuesLoadConfig(cfg *api.LoadConfig) {
c.retValLoadCfg = cfg
}
func (c *RPCClient) FunctionReturnLocations(fnName string) ([]uint64, error) {
var out FunctionReturnLocationsOut
err := c.call("FunctionReturnLocations", FunctionReturnLocationsIn{fnName}, &out)
return out.Addrs, err
}
func (c *RPCClient) IsMulticlient() bool {
var out IsMulticlientOut
c.call("IsMulticlient", IsMulticlientIn{}, &out)
return out.IsMulticlient
}
func (c *RPCClient) Disconnect(cont bool) error {
if cont {
out := new(CommandOut)
c.client.Go("RPCServer.Command", &api.DebuggerCommand{Name: api.Continue, ReturnInfoLoadConfig: c.retValLoadCfg}, &out, nil)
}
return c.client.Close()
}
func (c *RPCClient) ListDynamicLibraries() ([]api.Image, error) {
var out ListDynamicLibrariesOut
c.call("ListDynamicLibraries", ListDynamicLibrariesIn{}, &out)
return out.List, nil
}
func (c *RPCClient) ExamineMemory(address uintptr, count int) ([]byte, error) {
out := &ExaminedMemoryOut{}
err := c.call("ExamineMemory", ExamineMemoryIn{Length: count, Address: address}, out)
if err != nil {
return nil, err
}
return out.Mem, nil
}
func (c *RPCClient) StopRecording() error {
return c.call("StopRecording", StopRecordingIn{}, &StopRecordingOut{})
}
func (c *RPCClient) call(method string, args, reply interface{}) error {
return c.client.Call("RPCServer."+method, args, reply)
}
func (c *RPCClient) CallAPI(method string, args, reply interface{}) error {
return c.call(method, args, reply)
}