restic/debug.go

135 lines
2.6 KiB
Go

// +build debug
package restic
import (
"fmt"
"log"
"os"
"path"
"path/filepath"
"runtime"
"strings"
"syscall"
"time"
)
var debugLogger = initDebugLogger()
var debugTags = make(map[string]bool)
var debugBreak = make(map[string]bool)
func initDebugLogger() *log.Logger {
// create new log file
filename := fmt.Sprintf("restic-lib-debug-%d-%s",
os.Getpid(), time.Now().Format("20060201-150405"))
debugfile := filepath.Join(os.TempDir(), filename)
f, err := os.OpenFile(debugfile, os.O_WRONLY|os.O_CREATE, 0600)
if err != nil {
fmt.Fprintf(os.Stderr, "unable to create debug log file: %v", err)
os.Exit(2)
}
// open logger
l := log.New(f, "DEBUG: ", log.LstdFlags)
fmt.Fprintf(os.Stderr, "debug log for restic library activated, writing log file %s\n", debugfile)
// defaults
debugTags["break"] = true
// initialize tags
env := os.Getenv("DEBUG_TAGS")
if len(env) > 0 {
tags := []string{}
for _, tag := range strings.Split(env, ",") {
t := strings.TrimSpace(tag)
val := true
if t[0] == '-' {
val = false
t = t[1:]
} else if t[0] == '+' {
val = true
t = t[1:]
}
// test pattern
_, err := path.Match(t, "")
if err != nil {
fmt.Fprintf(os.Stderr, "error: invalid pattern %q: %v\n", t, err)
os.Exit(5)
}
debugTags[t] = val
tags = append(tags, tag)
}
fmt.Fprintf(os.Stderr, "debug log enabled for: %v\n", tags)
}
// initialize break tags
env = os.Getenv("DEBUG_BREAK")
if len(env) > 0 {
breaks := []string{}
for _, tag := range strings.Split(env, ",") {
t := strings.TrimSpace(tag)
debugBreak[t] = true
breaks = append(breaks, t)
}
fmt.Fprintf(os.Stderr, "debug breaks enabled for: %v\n", breaks)
}
return l
}
func debug(tag string, f string, args ...interface{}) {
dbgprint := func() {
fmt.Fprintf(os.Stderr, tag+": "+f, args...)
}
debugLogger.Printf(f, args...)
// check if tag is enabled directly
if v, ok := debugTags[tag]; ok {
if v {
dbgprint()
}
return
}
// check for globbing
for k, v := range debugTags {
if m, _ := path.Match(k, tag); m {
if v {
dbgprint()
}
return
}
}
// check if tag "all" is enabled
if v, ok := debugTags["all"]; ok && v {
dbgprint()
}
}
func debug_break(tag string) {
// check if breaking is enabled
if v, ok := debugBreak[tag]; !ok || !v {
return
}
_, file, line, _ := runtime.Caller(1)
debug("break", "stopping process %d at %s (%v:%v)\n", os.Getpid(), tag, file, line)
p, err := os.FindProcess(os.Getpid())
if err != nil {
panic(err)
}
err = p.Signal(syscall.SIGSTOP)
if err != nil {
panic(err)
}
}