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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <unistd.h>
#include <stdbool.h>
#include <linux/limits.h>
#define MAX_HISTORY 100
#define MAX_COMMAND_LENGTH 256
// static int CURRENT_COMMAND_INDEX = 0;
// static int CURRENT_HISTORY_INDEX = 0;
// static char *COMMAND_HISTORY[MAX_HISTORY] = { NULL};
struct com_struct
{
char *com;
char *arg;
};
void test()
{
printf("print to output");
}
// exit() command
void exit_()
{
exit(0);
}
// ls command
// get the requested path and put it into a const later on when getting the user input
void ls(const char *path)
{
fork();
struct dirent *entry;
DIR *dP = opendir(path);
// check if the directory got opened succefully
if (dP == NULL)
{
perror("opendir");
return;
}
// print the folder|directory name
while((entry = readdir(dP)) != NULL)
{
printf("s\n", entry->d_name);
}
closedir(dP);
}
// pwd command
char *pwd()
{
char *current_working_directory = malloc(sizeof(char) * 100);
if(getcwd(current_working_directory, sizeof(current_working_directory) != 0))
{
return current_working_directory;
}
else
{
perror("getcwd() error");
return "ERROR";
}
}
// echo command
char *echo(char *command)
{
char *argv = (char *)malloc(sizeof(char) * 4);
char *command_argument = (char *)malloc(sizeof(char) * 100);
int separation_index = 0;
for (int i = 0; i < sizeof(command); i++)
{
if (strcmp(&command[i], " ") == 0)
{
separation_index = i;
for ( int j = 0; j < separation_index; j++)
{
argv = &command[j];
}
}
}
if (strcmp(argv, "echo") == 0)
{
for (int i = separation_index + 1; i < (sizeof(command) - separation_index); i++)
{
if(strcmp(&command[i], "\0") != 0)
{
break;
}
else
{
strcpy(&command_argument[i - (separation_index - 1)], &command[i]);
}
}
}
return command_argument;
}
struct com_struct split_command(char *input)
{
// command bestaat uit 2 delen
// het commando zelf
// en argumenten voor het commado
// we moeten het commando opsplitsen in 2 delen
// we moeten een struct gebruiken
struct com_struct NEW_COMMAND;
char *command = (char *)malloc(sizeof(char) * 4);
char *argument = (char *)malloc(sizeof(char) * 100);
if (command == NULL || argument == NULL)
{
printf("found a null pointer when dynamically assigning memory to the command or variable argument");
exit(1);
}
int space_position = 0;
for (int i = 0; i < sizeof(command); i++)
{
if (strcmp(&input[i], " ") == 0)
{
space_position = i;
for ( int j = 0; j < space_position; j++)
{
command = &input[j];
}
for (int x = space_position; x < sizeof(input) - space_position; x++)
{
argument = &input[x];
}
}
}
NEW_COMMAND.com = command;
NEW_COMMAND.arg = argument;
return NEW_COMMAND;
}
int main(int argc, char *argv[])
{
char *input = malloc(sizeof(char *) * MAX_COMMAND_LENGTH);
while (true)
{
printf("\nSHELL> ");
scanf("%s", input);
// input converted to struct with members: command and argument
struct com_struct new_input = split_command(input);
if (strcmp(new_input.com, "ls"))
{
// failed logic, argv is for when executing the program, not for calling functions
}
}
return 0;
}
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