gg/main.go

182 lines
4.5 KiB
Go

/*
gg is a recursive grep written in Go, with some shortcuts for everyday use.
*/
package main
import (
"errors"
"fmt"
"os"
"path/filepath"
"regexp"
"github.com/bmatcuk/doublestar/v4"
"github.com/spf13/cobra"
"golang.org/x/sys/unix"
)
// TODO:
// - it would be better to make fixed patterns case insensitive too.
// - configurable defaults for exclude.
func main() {
if err := rootCmd.Execute(); err != nil {
os.Exit(1)
}
}
var rootCmd = &cobra.Command{
Use: "gg pattern [path1 [path2 …]]",
Short: "gg is a recursive grep",
Long: `gg is a recursive grep. Given a regexp (or fixed pattern) it will search for
the pattern recursively in the current working directory. It will print a
coloured header per file along with the matching line and pattern.
It is possible to scan specific files or directories, rather than the default
current working directory. To do this, simply specify the path(s) as arguments
following the pattern.
It is possible to scan for multiple patterns using the -e (or -Q) argument,
which can be repeated multiple times. -e specifies a regular expression and
-Q a fixed pattern. When using either flag, any non-flag arguments are treated
as paths to scan.
Search defaults to case-sensitive but the -i flag may be passed to make regular
expression searches case-insensitive. Alternatively, the "(?i)" construct may be
added to a regular expression to make that specific expression case insensitive.
Fixed pattern matches are always case-sensitive.
Files and directories can be excluded with the -x option. This supports bash-style
globs with '*', '?', '[a-z]', '{this,that}', or '/**/' to match zero or more
directories. By default, .git and vim swap files are ignored.`,
RunE: run,
}
var (
searchRegexp []string
regexps []*regexp.Regexp
searchFixed []string
searchBytes [][]byte
searchPath []string
excludeList []string
binaryFile notPlainTextFlag
minifiedFile notPlainTextFlag
ignoreCase bool
noColour bool
display *Display
printedFull bool
)
func init() {
rootCmd.Flags().StringSliceVarP(&searchRegexp, "grep", "e", nil, "pattern to match (regular expression)")
rootCmd.Flags().StringSliceVarP(&searchFixed, "fixed", "Q", nil, "pattern to match (fixed string)")
rootCmd.Flags().StringSliceVarP(&excludeList, "exclude", "x", []string{".git", ".*.swp"}, "files/directories to exclude")
rootCmd.Flags().BoolVarP(&ignoreCase, "ignore-case", "i", false, "make all searches case insensitive")
rootCmd.Flags().BoolVarP(&noColour, "no-colour", "C", false, "disable colour output")
rootCmd.Flags().Var(&binaryFile, "binary", "what to do with binary files")
rootCmd.Flags().Var(&minifiedFile, "minified", "what to do with minified text files")
}
func run(c *cobra.Command, args []string) error {
display = NewDisplay(noColour)
if len(searchRegexp) == 0 && len(searchFixed) == 0 {
if len(args) == 0 {
return errors.New("no pattern specified")
}
searchRegexp = append(searchRegexp, args[0])
args = args[1:]
}
searchPath = args
if len(searchPath) == 0 {
searchPath = append(searchPath, ".")
}
for _, x := range excludeList {
if !doublestar.ValidatePattern(x) {
return fmt.Errorf("invalid exclude pattern %q", x)
}
}
for _, r := range searchRegexp {
if ignoreCase {
r = "(?i)" + r
}
re, err := regexp.Compile(r)
if err != nil {
return err
}
regexps = append(regexps, re)
}
for _, s := range searchFixed {
searchBytes = append(searchBytes, []byte(s))
}
var errs []error
for _, path := range searchPath {
if err := search(path); err != nil {
errs = append(errs, err)
}
}
return errors.Join(errs...)
}
func recurse(path string) error {
d, err := os.ReadDir(path)
if err != nil {
return err
}
var errs []error
NextFile:
for _, de := range d {
name := de.Name()
fullPath := filepath.Join(path, name)
for _, x := range excludeList {
if exclude, _ := doublestar.Match(x, fullPath); exclude {
continue NextFile
}
}
if err := search(fullPath); err != nil {
errs = append(errs, err)
}
}
return errors.Join(errs...)
}
func search(path string) error {
st, err := os.Stat(path)
if err != nil {
return err
}
switch {
case st.IsDir():
return recurse(path)
case !st.Mode().IsRegular(),
st.Size() == 0:
return nil
}
f, err := os.Open(path)
if err != nil {
return err
}
defer f.Close()
data, err := unix.Mmap(int(f.Fd()), 0, int(st.Size()), unix.PROT_READ, unix.MAP_PRIVATE)
if err != nil {
return err
}
defer unix.Munmap(data)
file(path, data)
return nil
}