Merge pull request #5 from TriantaTV/development

Development

include/Common.h

@@ -1,11 +1,15 @@
 #ifndef COMMON_H
 #define COMMON_H
 
+const char* GetHomeDir(void);
+
 typedef struct CommandStruct {
     char* argv[100]; // Max 100 commands
     int argc;
+    char* envp[20]; // Enviroment Varibles
 } CommandStruct;
 
+void CopyCommandStruct(CommandStruct* oldCommand, CommandStruct* newCommand, int start, int end);
 void ResetCommandStruct(CommandStruct* command);
 
-#endif
+#endif

include/Integrated.h

@@ -3,15 +3,16 @@
 
 #include "Common.h"
 
-const char* GetHomeDir(void);
-void ioRedirection(CommandStruct *command);
+void CheckRedirection(CommandStruct* command);
+int CheckSymbol(CommandStruct* command, char symbol, int start);
+int CountSymbol(CommandStruct* command, char symbol);
 int IntegratedCheck(CommandStruct* command);
 void GetInput(char* inputString);
 void append(char *input, char *file);
 void input(char *command);
-void ExecPipe();
+int ExecPipe(CommandStruct* commandParent, CommandStruct* commandChild, int* pipefd);
 void output(char *command);
-void ParseInput(char* inputString, CommandStruct* command);
-void ReadPishrc(CommandStruct* command, char* inputString);
-
-#endif
+void SplitInput(char* inputString, CommandStruct* command);
+void ParseInput(char* inputString, CommandStruct* command, char* symbol);
+void ioRedirection(CommandStruct* command);
+#endif

include/Pish.h

@@ -4,5 +4,7 @@
 #include "Common.h"
 
 void Pish(void);
+void ReadPishrc(CommandStruct* commandParent, CommandStruct *commandChild, char* inputString);
+void RunChild(CommandStruct* commandChild, int* pipefd);
 
 #endif

src/Common.c

@@ -1,7 +1,28 @@
 #include "Common.h"
+#include <pwd.h>
 #include <string.h>
 #include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
 
+
+// Gets home directory location of user
+const char* GetHomeDir(void)
+{
+	char *homeDir = (getpwuid(getuid()))->pw_dir;
+	return homeDir;
+}
+
+// Copies a range of an old command object to new command object
+void CopyCommandStruct(CommandStruct* oldCommand, CommandStruct* newCommand, int start, int end)
+{
+    newCommand->argc = end - start;
+    for (int i = 0; i < newCommand->argc; i++)
+        newCommand->argv[i] = oldCommand->argv[i + start];
+    return;
+}
+
+// Resets entire command object
 void ResetCommandStruct(CommandStruct* command)
 {
     for (int i = 0; i < command->argc; i++)

src/Integrated.c

@@ -1,22 +1,13 @@
 #include <assert.h>
 #include <fcntl.h>
-#include <pwd.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/stat.h>
-#include <sys/types.h>
 #include <sys/wait.h>
 #include "Integrated.h"
 
-// Gets home directory location of user
-const char *GetHomeDir(void)
-{
-	char *homeDir = (getpwuid(getuid()))->pw_dir;
-	return homeDir;
-}
-
 // Checks for commands that are built into Pish
 int IntegratedCheck(CommandStruct *command)
 {
@@ -43,94 +34,119 @@ void GetInput(char *inputString)
 	printf("%s ", prompt);
 	// assert(scanf("%[^\n]s", inputString) == 1);
 	scanf("%1000[^\n]s", inputString);
-	while ((c = getchar()) != '\n' && c != EOF)
+	while ((c = getchar()) != '\n' && c != EOF) // Cleans input
 		/* discard */;
 	return;
 }
 
 // Splits a string separated by spaces into an array of strings
-void ParseInput(char *inputString, CommandStruct *command)
+void ParseInput(char *inputString, CommandStruct *command, char *symbol)
 {
 	// Parse command
 	int *argc = &(command->argc);
-	char *token = strtok(inputString, " ");
+	char *token = strtok(inputString, symbol);//change
 	command->argv[*argc] = token;
 	(*argc)++;
 	while (token != NULL)
 	{
 		// This only holds 1 command at a time then it overrides
 		// Will need modified
-		token = strtok(NULL, " ");
+	  token = strtok(NULL, symbol);//change
 		command->argv[*argc] = token;
 		(*argc)++;
 	}
 }
 
-// Reads ~/.pishrc and runs each command in the file
-void ReadPishrc(CommandStruct *command, char *inputString)
+// Splits a string separated by spaces into an array of strings
+void SplitInput(char *inputString, CommandStruct *command)
 {
-	char buffer[1];
-	int forkID;
 	int *argc = &(command->argc);
-	char* pishLocation = GetHomeDir();
-	strcat(pishLocation, "/.pishrc");
-	int fd = open(pishLocation, O_RDONLY | O_CREAT);
-	assert(fd > -1);
-	while (read(fd, buffer, 1) > 0)
+	char *token = strtok(inputString, " ");
+	command->argv[*argc] = token;
+	(*argc)++;
+	while (token != NULL)
 	{
-		if (buffer[0] == '\n')
-		{
-			ParseInput(inputString, command);
-			forkID = fork();
-			if (forkID == 0)
-				execvp(command->argv[0], command->argv);
-			else
-				wait(&forkID);
-			strcpy(inputString, "");
-			ResetCommandStruct(command);
-			continue;
-		}
-		strcat(inputString, buffer);
+		token = strtok(NULL, " ");
+		command->argv[*argc] = token;
+		(*argc)++;
 	}
-	assert(close(fd) >= 0);
+	(*argc)--;
 }
 
-// i/o redirection
-// TODO: Work on one symbol at a time
-// 		 inputString may not be useful here, only *command
-// 		 Try to add a layer of abstraction where possible
-// 		 I.E. think about using function instead for checking
-void ioRedirection(CommandStruct *command)
+// Splits a command array into left and right
+// void SplitPipe(CommandStruct* commandLeft, CommandStruct* commandRight);
+
+int CheckSymbol(CommandStruct* command, char symbol, int start)
 {
-	int newfd;
-	// check command standard output
+	for (int i = start; i < command->argc; i++)
+		if (command->argv[i][0] == symbol)
+			return i;
+	return -1;
+}
+
+// Checking redirection
+void CheckRedirection(CommandStruct* command)
+{
+	  // check command standard output
 	// TODO: Check command->argv[] for symbol instead
-	for(int i = 0; i < sizeof(command); i++)
-	{  
-		if (strchr(command->argv[i], '>') != NULL)
-		{
-			output(command->argv[i+1]); 
-		// 		 Check if targeting a specific string in command->argv works
-		}
-		if (strchr(command->argv[i], '<') != NULL)
-		{
-			input(command->argv[i+1]);
-		}
-		if (strchr(command->argv[i], '|')!= NULL)
-		{
-			// not sure if i + 1 correct
-			//  pipe(command->argv[i+1]);
-		}
-		if (strpbrk(command->argv[i], ">>")!= NULL)
-		{
-			append(command->argv[i-1], command->argv[i+1]);
-		}
+	for (int i = 0; i < command->argc; i++)
+	{
+		if ((command->argv[i][0] == '>') && (command->argv[i][1] == '>'))
+			printf(">> was found.\n");
+			// ParseInput(inputString, command, ">>");
+		if (command->argv[i][0] == '<')
+			printf("< was found.\n");
+			// ParseInput(inputString, command, "<");
+		if (command->argv[i][0] == '>' && command->argv[i][1] != '>')
+			printf("> was found.\n");
+			// ParseInput(inputString, command, ">");
+		if (command->argv[i][0] == '|')
+			printf("| was found.\n");
+			// ParseInput(inputString, command, "|");
+		// else
+		  	// ParseInput(inputString, command, " ");
 	}
+	return;
+}
+
+// Count number of appearances of a symbol in a CommandStruct
+int CountSymbol(CommandStruct* command, char symbol)
+{
+	int count = 0;
+	for (int i = 0; i < command->argc; i++)
+		if (command->argv[i][0] == symbol)
+			count++;
+	return count;
+}
+
+void ioRedirection(CommandStruct* command)
+{
+  for (int i = 0; i <sizeof(command); i++)
+  {
+      if (strpbrk(command->argv[i], ">>")!= NULL)//append
+      {
+         append(command->argv[i-1], command->argv[i+1]);
+      }
+      else if (command->argv[i][0] =='<')//input
+      {
+        input(command->argv[i+1]);
+      }  
+      else if (strchr(command->argv[i],'|')!= NULL)//pipe
+      {
+        //ExecPipe();
+      }
+      else if (command->argv[i][0] == '>')//output
+      {
+        output(command->argv[i+1]);
+      }
+      else{}
+       //exit
+    }
 }
 
 void output(char *command){
   int newfd;
-  if (newfd = open(command, O_CREAT | O_TRUNC | O_WRONLY, 0644) < 0)
+  if (newfd = open(command, O_CREAT | O_CREAT, 0666) < 0)
   {
     perror(command);
     exit(1);
@@ -141,7 +157,7 @@ void output(char *command){
 void input(char *command)
 {
 	int newfd;
-	if (newfd = open(command, O_RDONLY) < 0)
+	if (newfd = open(command, O_RDONLY | O_CREAT) < 0)
 	{
 		perror(command);
 		exit(1);
@@ -149,17 +165,53 @@ void input(char *command)
 	dup2(newfd,0);
 }
 
-void ExecPipe()
+// Splits a parent process into separate children processes
+int ExecPipe(CommandStruct* commandParent, CommandStruct* commandChild, int* pipefd)
 {
-	;
+	char buffer[1024];
+	int forkPID;
+	int pipeAmount = CountSymbol(commandParent, '|');
+	int pipeLocation = 0;
+	int startArgc = 0;
+	int endArgc = commandParent->argc;
+	pipe(pipefd);
+	for (int i = 0; i < pipeAmount; i++)
+	{
+		pipeLocation = CheckSymbol(commandParent, '|', startArgc);
+		endArgc = pipeLocation;
+		CopyCommandStruct(commandParent, commandChild, startArgc, endArgc);
+		forkPID = fork();
+		if (forkPID == 0)
+			return forkPID;
+		close(pipefd[0]);
+		close(pipefd[1]);
+		wait(&forkPID);
+		startArgc = pipeLocation + 1;
+        ResetCommandStruct(commandChild); // Clean command
+		pipe(pipefd);
+	}
+	endArgc = commandParent->argc;
+	forkPID = fork();
+	CopyCommandStruct(commandParent, commandChild, startArgc, endArgc);
+	if (forkPID == 0)
+		return forkPID;
+	close(pipefd[1]);
+	wait(&forkPID);
+	while (read(pipefd[0], buffer, sizeof(buffer)) != 0)
+		printf("%s", buffer);
+	close(pipefd[0]);
+	ResetCommandStruct(commandChild); // Clean command
+	return 1;
 }
 
-void append(char *input, char *file)
+void append(char* input, char* fileName)
 {
-	FILE *fp;
-	fp = fopen(file, "a+");
-	fputs(input, fp);
-	fclose(fp);
+	char buffer[4];
+	int fd = open(fileName, O_APPEND | O_CREAT);
+
+	// fp = fopen(file, "a+");
+	// fputs(input, fp);
+	// fclose(fp);
 }
 
 // check command standard input

src/Pish.c

@@ -1,43 +1,92 @@
 #include <assert.h>
+#include <fcntl.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/wait.h>
 #include <string.h>
+#include "Common.h"
 #include "Integrated.h"
 #include "Pish.h"
 
 // Main function for Pish program
 void Pish(void)
 {
-    CommandStruct commandObject = {"", 0};
-    CommandStruct* command = &commandObject;
+    CommandStruct commandParentObject = {"", 0};
+    CommandStruct commandChildObject = {"", 0};
+    CommandStruct* commandParent = &commandParentObject;
+    CommandStruct* commandChild = &commandChildObject;
     char inputString[1000]; // Max 1000 characters
     int forkPID;
-    ReadPishrc(command, inputString);
+	signal(SIGINT, SIG_IGN);
+	signal(SIGQUIT, SIG_IGN);
+	signal(SIGTERM, SIG_IGN);
+    ReadPishrc(commandParent, commandChild, inputString);
     while (1)
     {
-        ResetCommandStruct(command); // Clean command
+        int pipefd[2];
+        ResetCommandStruct(commandParent); // Clean command
         strcpy(inputString, "");    // Clean inputString
         GetInput(inputString);
-        ParseInput(inputString, command);
-	    if (IntegratedCheck(command))
+		if (strcmp(inputString, "") == 0)
+			continue;
+        SplitInput(inputString, commandParent);
+        if (IntegratedCheck(commandParent))
             continue;
-        forkPID = fork();
+        forkPID = ExecPipe(commandParent, commandChild, pipefd);
+        // CheckRedirection(inputString, command);
+        // CheckRedirection(command);
+        // ioRedirection(command);
         // Child
         if (forkPID == 0)
-        {
-            // This is the child process
-            // Setup the child's process environment here
-            // E.g., where is standard I/O, how to handle signals?
-            // execve() is recommended, execvpe() may be better
-            execvp(command->argv[0], command->argv);
-            // exec does not return if it succeeds
-            printf("ERROR: Could not execute %s\n", inputString);
-            exit(1);
-        }
+            RunChild(commandChild, pipefd);
         // Parent
         // This is the parent process; Wait for the child to finish
-        wait(&forkPID);
     }
 }
+
+// Reads ~/.pishrc and runs each command in the file
+void ReadPishrc(CommandStruct *commandParent, CommandStruct *commandChild, char *inputString)
+{
+	char buffer[1];
+	int pipefd[2];
+	int forkPID;
+	int *argc = &(commandParent->argc);
+	char* pishLocation = GetHomeDir();
+	strcat(pishLocation, "/.pishrc");
+	int fd = open(pishLocation, O_RDONLY | O_CREAT, 0644);
+	assert(fd > -1);
+	while (read(fd, buffer, 1) > 0)
+	{
+		if (buffer[0] == '\n')
+		{
+		  	SplitInput(inputString, commandParent);
+			if (IntegratedCheck(commandParent))
+				continue;
+			forkPID = ExecPipe(commandParent, commandChild, pipefd);
+			if (forkPID == 0)
+				RunChild(commandChild, pipefd);
+			strcpy(inputString, "");
+			ResetCommandStruct(commandParent);
+			continue;
+		}
+		strcat(inputString, buffer);
+	}
+	assert(close(fd) >= 0);
+}
+
+// Run a child process
+void RunChild(CommandStruct* commandChild, int* pipefd)
+{
+	close(pipefd[0]);
+	dup2(pipefd[1], 1);
+	close(pipefd[1]);
+	// execve() is recommended, execvpe() may be better
+	CheckRedirection(commandChild);
+	// ioRedirection(commandChild);
+	execvp(commandChild->argv[0], commandChild->argv);
+	// exec does not return if it succeeds
+	printf("ERROR: Could not execute %s\n", commandChild->argv[0]);
+	exit(1);
+}