feat: support grep & grep -v feature

cmd/cmd.go

@@ -1,16 +1,16 @@
 package cmd
 
 import (
+	"bufio"
 	"fmt"
+	"github.com/mstxq17/MoreFind/core"
 	"github.com/mstxq17/MoreFind/update"
 	"github.com/mstxq17/MoreFind/vars"
 	"github.com/spf13/cobra"
+	"log"
+	"strings"
 )
 
-func init() {
-	rootCmd.AddCommand(versionCmd)
-}
-
 var versionCmd = &cobra.Command{
 	Use:   "version",
 	Short: "Print the semantic version number of MoreFind",
@@ -26,3 +26,45 @@ var versionCmd = &cobra.Command{
 		fmt.Println("")
 	},
 }
+
+var pattern string
+var inverseMatch bool // Define a variable to hold the value of the inverse match flag
+
+var grepCmd = &cobra.Command{
+	Use:   "grep",
+	Short: "If no grep , use this",
+	Long:  `The grep command filters and displays lines matching a given pattern within files, akin to the Unix 'grep' command but without the second option.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		if len(args) == 1 {
+			pattern = args[0]
+		}
+		fileStdin, _ := handleStdin(file)
+		defer func() {
+			if err := fileStdin.Close(); err != nil {
+				log.Fatal(err)
+			}
+		}()
+		reader := bufio.NewReader(fileStdin)
+		scanner := bufio.NewScanner(reader)
+		buf := make([]byte, 0, 64*1024)
+		scanner.Buffer(buf, MaxTokenSize)
+		for scanner.Scan() {
+			line := strings.TrimSpace(scanner.Text())
+			matchLine, err := core.MatchLine(line, pattern, inverseMatch)
+			if err == nil && matchLine != "" {
+				fmt.Println(matchLine)
+			}
+		}
+	},
+}
+
+func init() {
+	// try other style to parse params
+	// 尝试使用不同的风格命令参数获取
+	grepCmd.Flags().StringVarP(&pattern, "pattern", "P", "", "Pattern to search")
+	grepCmd.Flags().BoolVarP(&inverseMatch, "inverse-match", "v", false, "Invert the match")
+	grepCmd.SetUsageTemplate(usageTemplate)
+	grepCmd.SetHelpTemplate(helpTemplate)
+	rootCmd.AddCommand(versionCmd)
+	rootCmd.AddCommand(grepCmd)
+}

cmd/cobra.go

@@ -0,0 +1,15 @@
+package cmd
+
+// Help template defines the format of the help message.
+var helpTemplate = `{{.Long | trim}}
+
+Usage:
+  {{.CommandPath}} [flags]
+{{if .Runnable}}
+Flags:
+{{.LocalFlags.FlagUsages | trimTrailingWhitespaces}}{{end}}
+
+`
+
+// Usage template defines the format of the usage message.
+var usageTemplate = `Usage: {{.CommandPath}} [flags]`

cmd/root.go

@@ -19,6 +19,10 @@ import (
 	"strings"
 )
 
+const (
+	MaxTokenSize = 512 * 1024 * 1024
+)
+
 var logger *log.Logger
 var NewLine string
 
@@ -240,6 +244,29 @@ func genIP(cidr string) {
 	}
 }
 
+func handleStdin(file string) (*os.File, os.FileInfo) {
+	var _file *os.File
+	if file != "" {
+		var err error
+		_file, err = os.Open(file)
+		if err != nil {
+			panic(err)
+		}
+	} else {
+		_file = os.Stdin
+	}
+	// use features to solve  whether  has input
+	// 利用特性解决程序是否有输入的问题
+	fi, _ := _file.Stat()
+	if (fi.Mode() & os.ModeCharDevice) != 0 {
+		logger.Println("No input found, exit ...")
+		// optimize exit logic
+		// 优化退出逻辑
+		os.Exit(0)
+	}
+	return _file, fi
+}
+
 func updateCommand(cmd *cobra.Command, args []string) {
 	callBackError := func() *log.Logger {
 		return logger
@@ -260,32 +287,16 @@ func preCommand(cmd *cobra.Command, args []string) bool {
 }
 
 func runCommand(cmd *cobra.Command, args []string) {
-	var _file *os.File
-	if file != "" {
-		var err error
-		_file, err = os.Open(file)
-		if err != nil {
-			panic(err)
+	// unified data stream
+	// 统一数据流
+	_file, fi := handleStdin(file)
+	// prevent memory leaking
+	// 防止内存泄漏
+	defer func() {
+		if err := _file.Close(); err != nil {
+			log.Fatal(err)
 		}
-		// prevent memory leaking
-		// 防止内存泄漏
-		defer func() {
-			if err = _file.Close(); err != nil {
-				log.Fatal(err)
-			}
-		}()
-	} else {
-		_file = os.Stdin
-	}
-	// use features to solve  whether  has input
-	// 利用特性解决程序是否有输入的问题
-	fi, _ := _file.Stat()
-	if (fi.Mode() & os.ModeCharDevice) != 0 {
-		logger.Println("No input found, exit ...")
-		// optimize exit logic
-		// 优化退出逻辑
-		os.Exit(0)
-	}
+	}()
 	// define global reader of input
 	// 定义全局输入读取流
 	var scanner *bufio.Scanner
@@ -303,7 +314,7 @@ func runCommand(cmd *cobra.Command, args []string) {
 	buf := make([]byte, 0, 64*1024)
 	// support maximum  512MB buffer every line
 	// 支持最大读取单行 512MB 大小
-	scanner.Buffer(buf, 512*1024*1024)
+	scanner.Buffer(buf, MaxTokenSize)
 	// todo: current structure may be chaotic, should abstract the handle process
 	if myCidr == "__pipe__" {
 		for scanner.Scan() {
@@ -548,6 +559,7 @@ func init() {
 	// help me a lot, so log it in the code， google dork: "flag needs an argument: cobra"
 	// 感谢 https://stackoverflow.com/questions/70182858/how-to-create-flag-with-or-without-argument-in-golang-using-cobra 提供了如何解决--filter 默认参数的问题
 	rootCmd.PersistentFlags().Lookup("filter").NoOptDefVal = "js,css,json,png,jpg,html,xml,zip,rar"
+
 	rootCmd.PersistentFlags().StringVarP(&myCidr, "cidr", "c", "", vars.CidrHelpEn)
 	rootCmd.PersistentFlags().Lookup("cidr").NoOptDefVal = "__pipe__"
 	rootCmd.PersistentFlags().StringVarP(&myLimitLen, "len", "l", "", vars.LimitLenHelpEn)

core/matcher.go

@@ -1 +1,17 @@
 package core
+
+import "regexp"
+
+func MatchLine(line, pattern string, inverse bool) (string, error) {
+	regexPattern, err := regexp.Compile(pattern)
+	if err != nil {
+		return "", err
+	}
+	if regexPattern.MatchString(line) && !inverse {
+		return line, nil
+	}
+	if !regexPattern.MatchString(line) && inverse {
+		return line, nil
+	}
+	return "", nil
+}