// GubTraceHook is the callback hook from interpreter. It contains
// top-level statement breakout.
func GubTraceHook(fr *interp.Frame, instr *ssa2.Instruction, event ssa2.TraceEvent) {
if !fr.I().TraceEventMask[event] {
return
}
gubLock.Lock()
defer gubLock.Unlock()
if skipEvent(fr, event) {
return
}
TraceEvent = event
frameInit(fr)
if instr == nil && event != ssa2.PROGRAM_TERMINATION {
instr = &curBlock.Instrs[fr.PC()]
}
Instr = instr
if event == ssa2.BREAKPOINT && Breakpoints[curBpnum].Kind == "Function" {
event = ssa2.CALL_ENTER
}
if FirstTime {
IntroText()
FirstTime = false
}
printLocInfo(topFrame, instr, event)
line := ""
var err error
for InCmdLoop = true; err == nil && InCmdLoop; cmdCount++ {
if inputReader != nil {
line, err = inputReader.ReadString('\n')
} else {
line, err = gnureadline.Readline(computePrompt(), true)
}
if err != nil {
break
}
line = strings.Trim(line, " \t\n")
args := strings.Split(line, " ")
if len(args) == 0 || len(args[0]) == 0 {
if len(LastCommand) == 0 {
Msg("Empty line skipped")
gnureadline.RemoveHistory(gnureadline.HistoryLength() - 1)
continue
} else {
line = LastCommand
args = strings.Split(line, " ")
}
}
if args[0][0] == '#' {
gnureadline.RemoveHistory(gnureadline.HistoryLength() - 1)
Msg(line) // echo line but do nothing
continue
}
name := args[0]
CmdArgstr = strings.TrimLeft(line[len(name):], " ")
if newname := LookupCmd(name); newname != "" {
name = newname
}
cmd := Cmds[name]
LastCommand = ""
if cmd != nil {
runCommand(name, args)
continue
}
if len(args) > 0 {
if !WhatisName(args[0]) {
gnureadline.RemoveHistory(gnureadline.HistoryLength() - 1)
}
} else {
gnureadline.RemoveHistory(gnureadline.HistoryLength() - 1)
Errmsg("Unknown command %s\n", cmd)
}
}
}
func printLocInfo(fr *interp.Frame, inst *ssa2.Instruction,
event ssa2.TraceEvent) {
defer func() {
if x := recover(); x != nil {
Errmsg("Internal error in getting location info")
debug.PrintStack()
}
}()
s := Event2Icon[event] + " "
fn := fr.Fn()
sig := fn.Signature
name := fn.Name()
if fn.Signature.Recv() != nil {
if len(fn.Params) == 0 {
panic("Receiver method " + name + " should have at least 1 param. Has 0.")
}
s += fmt.Sprintf("(%s).%s()", fn.Params[0].Type(), name)
} else {
s += fmt.Sprintf("%s.%s", fn.Pkg.Object.Path(), name)
if len(name) > 0 {
s += "()"
}
}
if *terse && (event != ssa2.STEP_INSTRUCTION) {
Msg(s)
} else {
Msg("%s block %d insn %d", s, fr.Block().Index, fr.PC())
}
var syntax ast.Node = nil
switch event {
case ssa2.CALL_RETURN:
if sig.Results() == nil {
Msg("return void")
} else {
Msg("return type: %s", sig.Results())
Msg("return value: %s", Deref2Str(fr.Result(), nil))
}
case ssa2.CALL_ENTER:
syntax = fn.Syntax()
for _, p := range fn.Params {
if val := fr.Env()[p]; val != nil {
ssaVal := ssa2.Value(p)
Msg("%s %s", p, Deref2Str(val, &ssaVal))
} else {
Msg("%s nil", p)
}
}
case ssa2.PANIC:
// fmt.Printf("panic arg: %s\n", fr.Get(instr.X))
}
Msg(fr.PositionRange())
if Instr != nil {
switch s := (*Instr).(type) {
case *ssa2.Trace:
syntax = s.Syntax()
}
if syntax != nil {
PrintSyntaxFirstLine(syntax, fn.Prog.Fset)
}
}
}