pish/src/Integrated.c

#include <assert.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include "Integrated.h"

// Checks for commands that are built into Pish
int IntegratedCheck(CommandStruct *command)
{
	if (strcmp(command->argv[0], "exit") == 0)
		exit(0);
	// If there is an argument, change to argument location
	// Else, change to home directory
	if (command->argv[0][0] == 'c' && command->argv[0][1] == 'd')
	{
		if (command->argv[1] != NULL)
			chdir(command->argv[1]);
		if (command->argv[1] == NULL)
			chdir(GetHomeDir());
		return 1;
	}
	return 0;
}

// Prints a prompt and then reads a command from the terminal
void GetInput(char *inputString)
{
	char c;
	char *prompt = "pish%>";
	printf("%s ", prompt);
	// assert(scanf("%[^\n]s", inputString) == 1);
	scanf("%1000[^\n]s", inputString);
	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, char *symbol)
{
	// Parse command
	int *argc = &(command->argc);
	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, symbol);//change
		command->argv[*argc] = token;
		(*argc)++;
	}
}

// Run child process
void RunChild(CommandStruct* commandChild, int* pipefd)
{
	close(pipefd[0]);
	dup2(pipefd[1], 1);
	close(pipefd[1]);
	// 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(commandChild->argv[0], commandChild->argv);
	// exec does not return if it succeeds
	printf("ERROR: Could not execute %s\n", commandChild->argv[0]);
	exit(1);
}


// Splits a string separated by spaces into an array of strings
void SplitInput(char *inputString, CommandStruct *command)
{
	// Parse command
	int *argc = &(command->argc);
	char *token = strtok(inputString, " ");
	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, " ");
		command->argv[*argc] = token;
		(*argc)++;
	}
	(*argc)--;
}

// Splits a command array into left and right
// void SplitPipe(CommandStruct* commandLeft, CommandStruct* commandRight);

int CheckSymbol(CommandStruct* command, char symbol, int start)
{
	for (int i = start; i < command->argc; i++)
		if (command->argv[i][0] == symbol)
			return i;
	return -1;
}


// Checking 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 CheckRedirection(CommandStruct* command)
{
	  // check command standard output
	// TODO: Check command->argv[] for symbol instead
	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] == '>')
			printf("> was found.\n");
			// ParseInput(inputString, command, ">");
		if (command->argv[i][0] == '|')
			printf("| was found.\n");
			// ParseInput(inputString, command, "|");
		// else
		  	// ParseInput(inputString, command, " ");
	}
	return;
}
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 (strchr(command->argv[i], '<')!= NULL)//input
      {
        input(command->argv[i+1]);
      }  
      else if (strchr(command->argv[i],'|')!= NULL)//pipe
      {
        //ExecPipe();
      }
      else if (strchr(command->argv[i], '>')!= NULL)//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)
  {
    perror(command);
    exit(1);
  }
  dup2(newfd,1);
}

void input(char *command)
{
	int newfd;
	if (newfd = open(command, O_RDONLY) < 0)
	{
		perror(command);
		exit(1);
	}
	dup2(newfd,0);
}

int ExecPipe(CommandStruct* commandParent, CommandStruct* commandChild, int* pipefd)
{
	char buffer[1024];
	int forkPID;
	int pipeLocation = 0;
	int startArgc = 0;
	int endArgc = commandParent->argc;
	while (pipeLocation >= 0)
	{
		if (pipeLocation > 0)
			startArgc = pipeLocation + 1;
		pipeLocation = CheckSymbol(commandParent, '|', startArgc);
		if (pipeLocation >= 0)
			endArgc = pipeLocation - 1;
		if (pipeLocation < 0)
			endArgc = commandParent->argc;
		CopyCommandStruct(commandParent, commandChild, startArgc, endArgc);
		pipe(pipefd);
		forkPID = fork();
		if (forkPID == 0)
			return forkPID;
		if (forkPID != 0)
			wait(&forkPID);
		close(pipefd[1]);
		while (read(pipefd[0], buffer, sizeof(buffer)) != 0)
			printf("%s", buffer);
        ResetCommandStruct(commandChild); // Clean command
	}
	return 1;
}

void append(char* input, char* fileName)
{
	char buffer[4];
	int fd = open(fileName, O_APPEND | O_CREAT);

	// fp = fopen(file, "a+");
	// fputs(input, fp);
	// fclose(fp);
}

// check command standard input
// if (strchr(inputString, '<') != NULL)
// {
// 	newfd = open((command, O_CREAT |O_TRUNC | O_WRONLY, 0644)) < 0);
// 	// No if statement for fail checking, brackets just exist here
// 	{
// 		// failed
// 		perror(command);
// 		exit(1);
// 	}
// 	dup2(newfd, 0);
// }

// check pipe
// TODO: Check for pipe symbol
//		 Check in command->argv[] instead
// if (strchr(command, '|') != NULL)
// {
// 	;
// }
// check append
// TODO: Implement append
// if (strpbrk(command, ">>") != NULL)
// {
// 	newfd = open((command, O_CREAT |O_TRUNC | O_WRONLY, 0644)) < 0);
// 	// No if statement for fail checking, brackets just exist here
// 	{	
// 		// failed
// 		perror(command);
// 		exit(1);
// 	}
// 	dup2(newfd, 0);
// }
// check pipe
// TODO: Check pipe already exists above, maybe loop?
// if (strchr(command, '|') != NULL)
// {
// 	;
// }
// check append
// TODO: Check append already exists above, maybe loop?
// if (strpbrk(command, ">>") != NULL)
// {
// 	;
// }

// Environment varibles
// TODO: Add this function to CommandStruct
//		 Environment Variables can just be a part of the struct
// void varibles(char str, int count)
// {
// 	char var[1000];
// 	var[count] = str;
// }