added input redirection

include/redirection.h

@@ -0,0 +1,8 @@
+#ifndef REDIRECTION_H
+#define REDIRECTION_H
+
+
+int detectRedirect(char **args, char **filename);
+void executeRedirect(char **args, int type, char *filename);
+
+#endif

main.c

@@ -6,6 +6,7 @@
 #include<readline/readline.h>
 #include<readline/history.h>
 #include<signal.h>
+#include"include/redirection.h"
 pid_t backgroundPids[64];
 int backgroundCount = 0;
 void handleSIGINT(int sig) {
@@ -112,6 +113,14 @@ int main() {
 		  free(parsed);
 		  continue;
 		}
+		char *filename;
+		int redirectionType = detectRedirect(parsed, &filename);
+		if (redirectionType) {
+		  executeRedirect(parsed, redirectionType, filename);
+		  free(parsed);
+		  free(line);
+		  continue;
+		}
 		pid_t pid = fork();
 		if(pid == 0) {
 		  signal(SIGINT, SIG_DFL);

makefile

@@ -2,8 +2,8 @@ CC = gcc
 CFLAGS = -Wall
 LIBS = -lreadline
 
-tinysh: main.c
+tinysh: main.c redirection.c
-	$(CC) $(CFLAGS) main.c -o tinysh $(LIBS)
+	$(CC) $(CFLAGS) main.c redirection.c -o tinysh $(LIBS)
 
 clean:
 	rm -f tinysh

redirection.c

@@ -0,0 +1,81 @@
+#include"include/redirection.h"
+#include<string.h>
+#include<fcntl.h>
+#include<unistd.h>
+#include<sys/wait.h>
+#include<signal.h>
+#include<stdio.h>
+#include<stdlib.h>
+int detectRedirect(char **args, char **filename) {
+  for(int i = 0; args[i] != NULL; i++) {
+    if(strcmp(args[i], "<") == 0) {
+      *filename = args[i + 1];
+      args[i] = NULL;
+      args[i + 1] = NULL;
+      return 3;
+    }
+    if(strcmp(args[i], ">") == 0) {
+      *filename = args[i + 1];
+      args[i] = NULL;
+      args[i + 1] = NULL;
+      return 1;
+    }
+    if(strcmp(args[i], ">>") == 0) {
+      *filename = args[i + 1];
+      args[i] = NULL;
+      args [i + 1] = NULL;
+      return 2;
+    }
+  }
+  return 0;
+}
+void executeRedirect(char **args, int type, char *filename) {
+  if (type == 1) {
+    int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+    pid_t pid = fork();
+    if(pid == 0) {
+      dup2(fd, STDOUT_FILENO);
+      close(fd);
+      signal(SIGINT, SIG_DFL);
+      execvp(args[0], args);
+      perror("tinysh");
+      exit(1);
+    }
+    else if(pid > 0) {
+      close(fd);
+      wait(NULL);
+    }
+  }
+  if (type == 2) {
+    int fd = open(filename, O_WRONLY | O_CREAT | O_APPEND, 0644);
+    pid_t pid = fork();
+    if(pid == 0) {
+      dup2(fd, STDOUT_FILENO);
+      close(fd);
+      signal(SIGINT, SIG_DFL);
+      execvp(args[0], args);
+      perror("tinysh");
+      exit(1);
+    }
+    if (pid > 0) {
+      close(fd);
+      wait(NULL);
+    }
+  }
+  if (type == 3) {
+    int fd = open(filename, O_RDONLY);
+    pid_t pid = fork();
+    if (pid == 0) {
+      dup2(fd, STDIN_FILENO);
+      close(fd);
+      signal(SIGINT, SIG_DFL);
+      execvp(args[0], args);
+      perror("tinysh");
+      exit(1);
+    }
+    else if (pid > 0) {
+      close(fd);
+      wait(NULL);
+    }
+  }
+}