From 436f550ffa4c23b9480d8993283f4236ff782fbd Mon Sep 17 00:00:00 2001
From: 10195501441 <10195501441@stu.ecnu.edu.com>
Date: Tue, 16 Mar 2021 11:28:41 +0800
Subject: [PATCH] added redirect

---
 .vscode/settings.json |  7 ++++++
 yeeshell.c            | 63 +++++++++++++++++++++++++++++++++++++++++++++++----
 yeeshell.h            |  7 ++++++
 3 files changed, 72 insertions(+), 5 deletions(-)
 create mode 100644 .vscode/settings.json

diff --git a/.vscode/settings.json b/.vscode/settings.json
new file mode 100644
index 0000000..d0e4917
--- /dev/null
+++ b/.vscode/settings.json
@@ -0,0 +1,7 @@
+{
+    "files.associations": {
+        "yeeshell.h": "c",
+        "types.h": "c",
+        "signal.h": "c"
+    }
+}
\ No newline at end of file
diff --git a/yeeshell.c b/yeeshell.c
index c7e0e5f..d9f0663 100644
--- a/yeeshell.c
+++ b/yeeshell.c
@@ -8,6 +8,8 @@
 #include <dirent.h>
 #include <signal.h>
 #include <errno.h>
+#include <ctype.h>
+#include <fcntl.h>
 #include "yeeshell.h"
 
 /* record cmdline history */
@@ -64,6 +66,7 @@ int main()
 	{
 		free(history[i]);
 	}
+	free(history);
 	exit(EXIT_SUCCESS);
 }
 
@@ -137,14 +140,36 @@ int parseline(char *cmdline, char **args)
 	return bg;
 }
 
+int redirect(char **args, char *redirect_file, char **redirect_args)
+{
+	int i = 0;
+	while (args[i] != NULL)
+	{
+		redirect_args[i] = args[i];
+		if (args[i + 1] == ">")
+		{
+			redirect_file = args[i + 2];
+			return OUT_REDRT;
+		}
+		else if (args[i + 1] == "<")
+		{
+			redirect_file = args[i + 2];
+			return IN_REDRT;
+		}
+	}
+	return NO_REDRT;
+}
+
 int execute(char *cmdline, char **args)
 {
-	int bg = 0, i = 0;
+	int bg = 0, redirect_flag = 0, fd = 0;
+	char *redirect_file, *redirect_args[ARGS_MAX_QUANTITY];
 	pid_t pid;
 	sigset_t mask_all, mask_prev;
 	sigprocmask(SIG_BLOCK, NULL, &mask_all);
 	sigaddset(&mask_all, SIGCHLD);
 	bg = parseline(cmdline, args);
+	redirect_flag = redirect(args, redirect_file, redirect_args);
 
 	if (args[0] == NULL)
 	{
@@ -164,6 +189,38 @@ int execute(char *cmdline, char **args)
 			/* Set the pid of the current process to the group number of the process group it belongs to. */
 			/* avoid being grouped with tsh */
 			setpgid(0, 0);
+
+			switch (redirect_flag)
+			{
+			case 0: /* no redirection */
+				if (execvp(args[0], args) <= 0)
+				{
+					printf("%s: Command not found\n", args[0]);
+					exit(0);
+				}
+				break;
+			case 1: /* redirect output */
+				fd = open(redirect_file, O_CREAT | O_WRONLY | O_TRUNC, 0664);
+				dup(fd, 1);
+				if (execvp(args[0], redirect_args) <= 0)
+				{
+					printf("%s: Command not found\n", args[0]);
+					exit(0);
+				}
+				break;
+			case 2: /* redirect input */
+				fd = open(info.in_file, O_CREAT | O_RDONLY, 0666);
+				close(fileno(stdin));
+				dup2(fd, fileno(stdin));
+				close(fd);
+				if (execvp(args[0], redirect_args) <= 0)
+				{
+					printf("%s: Command not found\n", args[0]);
+					exit(0);
+				}
+				break;
+			}
+
 			if (execvp(args[0], args) <= 0)
 			{
 				printf("%s: Command not found\n", args[0]);
@@ -172,10 +229,6 @@ int execute(char *cmdline, char **args)
 		}
 		else
 		{
-			do
-			{
-			} while (!args[i++]);
-
 			if (bg) /* bg task */
 			{
 				addjob(jobs, pid, BG, cmdline);
diff --git a/yeeshell.h b/yeeshell.h
index 7fa40cb..c2cd9c6 100644
--- a/yeeshell.h
+++ b/yeeshell.h
@@ -14,6 +14,10 @@
 #define BG 2   /* running in background */
 #define ST 3   /* stopped */
 
+#define NO_REDRT 0  /* no redirection */
+#define OUT_REDRT 1 /* the latter is output */
+#define IN_REDRT 2  /* the former is input */
+
 /* job_t - The job struct */
 struct job_t
 {
@@ -29,6 +33,9 @@ char *readline();
 /* parseline - Evaluate the command line that the user has just typed in */
 int parseline(char *cmdline, char **args);
 
+/* redirect - Judge if the command contains redirection */
+int redirect(char **args, char *redirect_file, char **redirect_args);
+
 /* execute - Execute the command line */
 int execute(char *cmdline, char **args);