1 files changed, 236 insertions, 0 deletions
diff --git a/internal/debug/api.go b/internal/debug/api.go
new file mode 100644
index 0000000..86a4218
--- /dev/null
+++ b/internal/debug/api.go
@@ -0,0 +1,236 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// Package debug interfaces Go runtime debugging facilities.
+// This package is mostly glue code making these facilities available
+// through the CLI and RPC subsystem. If you want to use them from Go code,
+// use package runtime instead.
+package debug
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"os"
+	"os/user"
+	"path/filepath"
+	"runtime"
+	"runtime/debug"
+	"runtime/pprof"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// Handler is the global debugging handler.
+var Handler = new(HandlerT)
+
+// HandlerT implements the debugging API.
+// Do not create values of this type, use the one
+// in the Handler variable instead.
+type HandlerT struct {
+	mu        sync.Mutex
+	cpuW      io.WriteCloser
+	cpuFile   string
+	traceW    io.WriteCloser
+	traceFile string
+}
+
+// Verbosity sets the log verbosity ceiling. The verbosity of individual packages
+// and source files can be raised using Vmodule.
+func (*HandlerT) Verbosity(level int) {
+	glogger.Verbosity(log.Lvl(level))
+}
+
+// Vmodule sets the log verbosity pattern. See package log for details on the
+// pattern syntax.
+func (*HandlerT) Vmodule(pattern string) error {
+	return glogger.Vmodule(pattern)
+}
+
+// BacktraceAt sets the log backtrace location. See package log for details on
+// the pattern syntax.
+func (*HandlerT) BacktraceAt(location string) error {
+	return glogger.BacktraceAt(location)
+}
+
+// MemStats returns detailed runtime memory statistics.
+func (*HandlerT) MemStats() *runtime.MemStats {
+	s := new(runtime.MemStats)
+	runtime.ReadMemStats(s)
+	return s
+}
+
+// GcStats returns GC statistics.
+func (*HandlerT) GcStats() *debug.GCStats {
+	s := new(debug.GCStats)
+	debug.ReadGCStats(s)
+	return s
+}
+
+// CpuProfile turns on CPU profiling for nsec seconds and writes
+// profile data to file.
+func (h *HandlerT) CpuProfile(file string, nsec uint) error {
+	if err := h.StartCPUProfile(file); err != nil {
+		return err
+	}
+	time.Sleep(time.Duration(nsec) * time.Second)
+	h.StopCPUProfile()
+	return nil
+}
+
+// StartCPUProfile turns on CPU profiling, writing to the given file.
+func (h *HandlerT) StartCPUProfile(file string) error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	if h.cpuW != nil {
+		return errors.New("CPU profiling already in progress")
+	}
+	f, err := os.Create(expandHome(file))
+	if err != nil {
+		return err
+	}
+	if err := pprof.StartCPUProfile(f); err != nil {
+		f.Close()
+		return err
+	}
+	h.cpuW = f
+	h.cpuFile = file
+	log.Info("CPU profiling started", "dump", h.cpuFile)
+	return nil
+}
+
+// StopCPUProfile stops an ongoing CPU profile.
+func (h *HandlerT) StopCPUProfile() error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	pprof.StopCPUProfile()
+	if h.cpuW == nil {
+		return errors.New("CPU profiling not in progress")
+	}
+	log.Info("Done writing CPU profile", "dump", h.cpuFile)
+	h.cpuW.Close()
+	h.cpuW = nil
+	h.cpuFile = ""
+	return nil
+}
+
+// GoTrace turns on tracing for nsec seconds and writes
+// trace data to file.
+func (h *HandlerT) GoTrace(file string, nsec uint) error {
+	if err := h.StartGoTrace(file); err != nil {
+		return err
+	}
+	time.Sleep(time.Duration(nsec) * time.Second)
+	h.StopGoTrace()
+	return nil
+}
+
+// BlockProfile turns on goroutine profiling for nsec seconds and writes profile data to
+// file. It uses a profile rate of 1 for most accurate information. If a different rate is
+// desired, set the rate and write the profile manually.
+func (*HandlerT) BlockProfile(file string, nsec uint) error {
+	runtime.SetBlockProfileRate(1)
+	time.Sleep(time.Duration(nsec) * time.Second)
+	defer runtime.SetBlockProfileRate(0)
+	return writeProfile("block", file)
+}
+
+// SetBlockProfileRate sets the rate of goroutine block profile data collection.
+// rate 0 disables block profiling.
+func (*HandlerT) SetBlockProfileRate(rate int) {
+	runtime.SetBlockProfileRate(rate)
+}
+
+// WriteBlockProfile writes a goroutine blocking profile to the given file.
+func (*HandlerT) WriteBlockProfile(file string) error {
+	return writeProfile("block", file)
+}
+
+// MutexProfile turns on mutex profiling for nsec seconds and writes profile data to file.
+// It uses a profile rate of 1 for most accurate information. If a different rate is
+// desired, set the rate and write the profile manually.
+func (*HandlerT) MutexProfile(file string, nsec uint) error {
+	runtime.SetMutexProfileFraction(1)
+	time.Sleep(time.Duration(nsec) * time.Second)
+	defer runtime.SetMutexProfileFraction(0)
+	return writeProfile("mutex", file)
+}
+
+// SetMutexProfileFraction sets the rate of mutex profiling.
+func (*HandlerT) SetMutexProfileFraction(rate int) {
+	runtime.SetMutexProfileFraction(rate)
+}
+
+// WriteMutexProfile writes a goroutine blocking profile to the given file.
+func (*HandlerT) WriteMutexProfile(file string) error {
+	return writeProfile("mutex", file)
+}
+
+// WriteMemProfile writes an allocation profile to the given file.
+// Note that the profiling rate cannot be set through the API,
+// it must be set on the command line.
+func (*HandlerT) WriteMemProfile(file string) error {
+	return writeProfile("heap", file)
+}
+
+// Stacks returns a printed representation of the stacks of all goroutines.
+func (*HandlerT) Stacks() string {
+	buf := new(bytes.Buffer)
+	pprof.Lookup("goroutine").WriteTo(buf, 2)
+	return buf.String()
+}
+
+// FreeOSMemory returns unused memory to the OS.
+func (*HandlerT) FreeOSMemory() {
+	debug.FreeOSMemory()
+}
+
+// SetGCPercent sets the garbage collection target percentage. It returns the previous
+// setting. A negative value disables GC.
+func (*HandlerT) SetGCPercent(v int) int {
+	return debug.SetGCPercent(v)
+}
+
+func writeProfile(name, file string) error {
+	p := pprof.Lookup(name)
+	log.Info("Writing profile records", "count", p.Count(), "type", name, "dump", file)
+	f, err := os.Create(expandHome(file))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return p.WriteTo(f, 0)
+}
+
+// expands home directory in file paths.
+// ~someuser/tmp will not be expanded.
+func expandHome(p string) string {
+	if strings.HasPrefix(p, "~/") || strings.HasPrefix(p, "~\\") {
+		home := os.Getenv("HOME")
+		if home == "" {
+			if usr, err := user.Current(); err == nil {
+				home = usr.HomeDir
+			}
+		}
+		if home != "" {
+			p = home + p[1:]
+		}
+	}
+	return filepath.Clean(p)
+}