func main() {
myflags := flag.NewFlagSet("tffilter", flag.ExitOnError)
cfg := &tf.TffilterConfig{}
cfg.DefineFlags(myflags)
err := myflags.Parse(os.Args[1:])
err = cfg.ValidateConfig()
if err != nil {
usage(err, myflags)
}
if cfg.Help {
fmt.Fprintf(os.Stderr, "help requested:\n")
usage(nil, myflags)
}
leftover := myflags.Args()
regs := leftover
//p("regs = %v", regs)
if cfg.RegexFile != "" {
regs, err = tf.ReadNewlineDelimFile(cfg.RegexFile)
if err != nil {
fmt.Fprintf(os.Stderr, "error reading -regexfile '%s': '%s'\n", cfg.RegexFile, err)
usage(err, myflags)
}
if len(regs) == 0 {
fmt.Fprintf(os.Stderr, "no regex given from file '%s': specify at least one regex to filter with.\n", cfg.RegexFile)
showUse(myflags)
os.Exit(1)
}
} else {
if len(regs) == 0 || (len(regs) == 1 && strings.HasPrefix(regs[0], "-h")) {
fmt.Fprintf(os.Stderr, "no regex given: specify at least one regex to filter with.\n")
showUse(myflags)
os.Exit(1)
}
}
// INVAR: regs specified, and len(regs) > 0
arrRegex := make([]*regexp.Regexp, 0)
for i := range regs {
field := regs[i]
//fmt.Fprintf(os.Stderr, "compiling regex %d: '%s'\n", i, field)
re := regexp.MustCompile(field)
arrRegex = append(arrRegex, re)
}
i := int64(1)
fr := tf.NewFrameReader(os.Stdin, 1024*1024)
var frame tf.Frame
var raw []byte
n := len(regs)
var allMatched, anyMatched bool
toploop:
for ; err == nil; i++ {
_, _, err, raw = fr.NextFrame(&frame)
if err != nil {
if err == io.EOF {
break toploop
}
fmt.Fprintf(os.Stderr, "tffilter error from fr.NextFrame() at i=%v: '%v'\n", i, err)
os.Exit(1)
}
str := frame.Stringify(-1, false, false, false)
// match regex
matchN := 0
var o string
var sub []string
for _, r := range arrRegex {
if cfg.Sub {
sub = r.FindStringSubmatch(str)
//p("sub back from r.FindStringSubmatch(str='%s') is '%#v' from regex '%s'", str, sub, regs[j])
if sub == nil {
o = ""
} else {
o = "hit"
}
} else {
o = r.FindString(str)
}
//fmt.Fprintf(os.Stderr, "tffilter at i=%v, matching frame '%s' against regex '%s': output is: '%s'\n", j, str, regs[j], o)
if o != "" {
matchN++
switch {
// we have a match
case cfg.Any:
// found at least one match, we can stop under Any
switch {
case cfg.ExcludeMatches:
continue toploop
case !cfg.ExcludeMatches:
goto writeout
}
}
} else {
// not a match
switch {
case !cfg.Any && cfg.ExcludeMatches:
// we've got to match all n in order to exclude, so we know now that we will include.
goto writeout
case !cfg.Any && !cfg.ExcludeMatches:
// not a match, and all must match to survive the filter, so we can stop
continue toploop
}
}
}
allMatched = (matchN == n)
anyMatched = (matchN > 0)
switch {
case cfg.Any && cfg.ExcludeMatches:
if anyMatched {
continue toploop
}
goto writeout
case cfg.Any && !cfg.ExcludeMatches:
if anyMatched {
goto writeout
}
continue toploop
case !cfg.Any && cfg.ExcludeMatches:
if allMatched {
continue toploop
}
goto writeout
case !cfg.Any && !cfg.ExcludeMatches:
if allMatched {
goto writeout
}
continue toploop
}
writeout:
if cfg.Sub {
// sub-expression matching and reporting only the sub matches
//p("sub = %#v", sub)
sub = sub[1:]
//p("sub[1:] = %#v", sub)
nsub := len(sub)
if nsub > 0 {
for k := range sub {
fmt.Printf("%s", sub[k])
if k < nsub-1 {
fmt.Printf(" ", sub[k])
}
}
fmt.Printf("\n")
}
} else {
// full record matching
_, err = os.Stdout.Write(raw)
if err != nil {
fmt.Fprintf(os.Stderr, "tffilter stopping at: '%s'", err)
}
}
} // end for toploop
//fmt.Fprintf(os.Stderr, "field='%s': found %v matches.\n", field, matchCount)
}
